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Nora Maria ANDREOLA
Personale tecnico amministrativo
Dipartimento di Ingegneria "Enzo Ferrari"
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Pubblicazioni
2023
- Characterization of Volcano-Sedimentary Rocks and Related Scraps for Design of Sustainable Materials
[Articolo su rivista]
Barbieri, L.; Altimari, F.; Andreola, F.; Maggi, B.; Lancellotti, I.
abstract
This work started as a joint academia and company research project with the aim of finding
new applications for domestically sourced volcanic products and related waste (pumice, lapillus,
zeolitic tuff and volcanic debris from Tessennano and Arlena quarry) by creating a database of
secondary volcanic raw materials and their intrinsic characteristics to help industry replace virgin
materials and enhance circularity. In this context, accurate chemical, mineralogical, morphological,
granulometric and thermal characterizations were performed. Based on the results presented, it can
be concluded that due to their lightness, these materials can be used in the design and preparation of
lightweight aggregates for agronomic purposes or in the construction field. Furthermore, due to their
aluminosilicate nature and amorphous fraction, pumice and lapillus can play the role of precursor or
activator for geopolymer preparation. With its porous nature, zeolitic tuff can be exploited for flue
gas treatment. Due to the presence of feldspathic phase (sanidine), these materials can be used in
tile production as a fluxing component, and with their pozzolanic activity and calcium content, they
have application in the binder field as supplementary cementitious material or as aggregates.
2023
- Green materials for construction industry from Italian volcanic quarry scraps
[Articolo su rivista]
Altimari, F.; Lancellotti, I.; Leonelli, C.; Andreola, F.; Elsayed, H.; Bernardo, E.; Barbieri, L.
abstract
Italian volcanic quarry scraps, with fine particle size and of little market interest, have been considered for the
manufacturing of lightweight geopolymers and highly porous foams. Both powders have been alkali activated
with NaOH solution at 8 M and 3 M, respectively.
Geopolymers were characterized in terms of density, porosity, humidity absorption/desorption, mechanical
strength and microstructure. All samples (with a bulk density of 1.5–1.6 g/cm3) exhibited a porosity of
approximatively 35 vol% but featured a quite variable compressive strength (3–7 MPa), depending on the use of
pumice or lapillus. The same quarry scraps were easily converted into highly porous foams (porosity of 75 vol%),
by intensive mechanical stirring of alkali-activated suspensions, with the help of a surfactant.
2023
- Pumice and lapillus scraps: New national environmental-friendly chance for the production of ceramic tiles
[Articolo su rivista]
Altimari, F.; Andreola, F.; Benassi, P. P.; Lancellotti, I.; Barbieri, L.
abstract
Italian pumice and volcanic lapillus scraps have been used in different percentages as alternative raw materials to
foreign feldspars in porcelain stoneware mixtures. The aim of this work was to create naturally colored support to
limit the use of artificial dyes while maintaining the technical properties of the reference product. For this
purpose, the significant presence of chromophores (Fe and Ti in particular) in by-products from extraction of
Italian volcanic pumice and lapillus was exploited. The work was carried out in collaboration with a company:
the products were made on a laboratory scale and then they were glazed and fired within the industrial production
cycle (48 min, 1210 ◦C).
The resulting slip and the fired samples were characterized by measuring the efflux time, density, linear
shrinkage, water absorption and tensile strength to evaluate the technological performance. In addition, thermogravimetric
analysis (TG), differential thermal analysis (DTA), and optical and mechanical dilatometry were
performed to study the thermal behavior of the formulations.
The obtained products could be classified as porcelain stoneware and belong to the BIa group (WA 0.5%, B.
S.>35 MPa) in accordance with UNI EN 14411 ISO 13006.
2022
- A New System of Sustainable Silico-Aluminous and Silicate Materials for Cultivation Purpose within Sustainable Buildings: Chemical-Physical, Antibacterial and Cytotoxicity Properties
[Articolo su rivista]
Catauro, M.; Poggetto, G. D.; Pacifico, S.; Andreola, F.; Lancellotti, I.; Barbieri, L.
abstract
In this study, we compared the chemical-physical, antibacterial, and cytotoxicity properties of silico-aluminous and silicate materials for outdoor (green roof, planted walls) and indoor (urban farms, indoor microgreen gardens) cultivation purpose in a context of sustainable construction. Glasses and lightweight aggregates were tailored starting from waste, by-product, and post-consumer and bioproducts (packaging glass cullet, cattle bone flour ash, vegetable biomass ash, spent coffee ground, degreased from biomass of prepupae of Black Soldier Flies) mixed together with a national ferruginous red clay, quarry scrap pumice and, if necessary, with K2CO3 of reagent grade. The first type of material was obtained by melting at 1200 °C and the second one by powder sintering at 1000 °C. All specimens, subjected to antibacterial test, showed both low zone of inhibitions towards two Gram-negative and two Gram-positive bacterial strains. A cytotoxicity test on mouse embryonic fibroblast NIH-3T3 cell line directly exposed to the investigated materials was performed at three different exposure times (1 h, 3 h, and 6 h). Data acquired highlighted that the materials positively affected redox mitochondrial activity of the fibroblast cells. The concentrations of leachate heavy metals detected on selected materials in water at room temperature after 24 h were lower than the European law limit and an interesting release of P, K, and N nutrients was noted for those formulations designed for agronomic purposes. pH, falling on average within the 6.5–7.5 range, is optimal for most crops, and the specific conductivity <2 dS/m indicates no depression danger for crops. Both bulk density <1200 kg/m3 and porosity over 50% seem to ensure good performance of lightening, drainage, water reservation, and oxygenation of the roots.
2022
- Management of agricultural waste biomass as raw material for the construction sector: an analysis of sustainable and circular alternatives
[Articolo su rivista]
Duque-Acevedo, Mónica; Lancellotti, Isabella; Andreola, Fernanda; Barbieri, Luisa; Belmonte-Ureña, Luis J.; Camacho-Ferre, Francisco
abstract
The agricultural and construction sectors demand enormous amounts of natural resources and generate environmental impacts that negatively affect ecosystems. One of the main problems is the generation and inadequate management of waste. For this reason, under the approaches of the new sustainable and circular models, waste valorization has been prioritised as a strategy for advancing towards the sustainability of production systems. This research aims to carry out a general analysis of Agricultural Waste Biomass (AWB) in the production of bio-based products for the construction sector. Bibliometric techniques were applied for the general analysis of the scientific production obtained from Scopus. A systematic review identified the main research approaches. In addition, European projects were reviewed to assess the practical application. This study is novel and provides relevant contributions to new trends in the valorisation of AWB in the building sector and the sustainability benefits. For policymakers, it is a source of information on the contribution of new policies to scientific advances and the aspects that need to be strengthened to improve sustainable and circular practices in both sectors.
2022
- Pyrolysis Process for the Recycling of Cork Dust Waste from the Processing of Cork Agglomerate Caps in Lightweight Materials
[Articolo su rivista]
Coppelli, Paride; Pedrazzi, Simone; Puglia, Marco; Morselli, Nicolo'; Allesina, Giulio; Andreola, Nora Maria; Lancellotti, Isabella; Barbieri, Luisa
abstract
This study aimed to investigate the possibility of recycling cork scraps derived from the production of agglomerated bottle caps containing organic additives (glues and adhesives) in addition to virgin wood. The study involved pyrolysis treatment followed by the use of char to obtain lightweight material prototypes. The scrap was pyrolysed in order to achieve the thermal degradation of unwanted molecules with decomposition temperatures lower than the pyrolysis temperatures, but also to achieve the reduction in mass and size of the starting material. The substitution of 15% by weight of weight-lightening agent (char from pyrolysed cork, or half char and half spent coffee grounds) into the clayey matrix made it possible to obtain lightweight aggregates with pH and conductivity values that could be exploited in an agronomic context. The substitution of clay with of 5 to 15% by weight of pyrolysed cork char in the production of specimens pressed at 25 bar and fired slowly at 1000 ◦C led to lightweight ceramics with particularly interesting porosity (from 41 to 68%) and bulk density (850–1600 kg/m3) values.
2022
- Suitability of Porous Inorganic Materials from Industrial Residues and Bioproducts for Use in Horticulture: A Multidisciplinary Approach
[Articolo su rivista]
Righi, Claudia; Barbieri, Francesco; Sgarbi, Elisabetta; Maistrello, Lara; Bertacchini, Alessandro; Andreola, Nora Maria; D’Angelo, Antonio; Catauro, Michelina; Barbieri, Luisa
abstract
This study follows a circular economy approach through the preliminary implementation of a coated porous inorganic material (PIM), studied as sustainable controlled release fertilizer, and its application for lettuce Lactuca sativa L. cultivar Chiara growth. The PIM was made of pumice scraps that partially replaced clay as a natural raw material, spent coffee grounds as a porous agent, bovine bone ash and potassium carbonate to provide phosphorus (P) and potassium (K) nutrients, respectively. A coating made with defatted black soldier fly prepupae biomass was used as a nitrogen (N) source. Most of the ingredients used were industrial residues, with the aim of valorizing the raw waste materials present locally. The suitability of PIMs as a fertilizer was investigated with an interdisciplinary approach, which included the first chemical and physical characterization of the material, the evaluation of its antibacterial properties and of its use in horticulture through lettuce growth tests. As tests were carried out indoors, a specific LED lighting device was used to grow the lettuce. The release of nutrients into the soil was estimated by measuring the main elements in the fertilizers before and after their use in the soil. The first results from this characterization study support PIMs’ suitability for agronomic applications. The use of the PIMs suggested average higher dry weight (49%), fresh weight (112%), and leaf area (48%), compared to those with the use of a standard fertilizer soil, without the release of any dangerous element for the plant in the soil. These results are a promising beginning for the development of further studies already in progress on sustainable controlled-release fertilizers.
2022
- Sustainable glasses in the SiO2–P2O5–CaO–K2O system from waste and concentrated solar power
[Articolo su rivista]
Romero, M.; Padilla, I.; Barbieri, L.; Andreola, F.; Lopez-Delgado, A.
abstract
Sustainable glasses were prepared by green technology including the use of different wastes as raw materials and concentrated solar power (CSP) as renewable energy. The raw materials used to formulate the glasses were animal bone flour ash, which presents high contents of CaO, P2O5 and alkaline oxides; glassy sand from the waste of packaging glass submitted to a primary treatment, composed principally of SiO2; and potassium carbonate of reagent grade. Different exposure times to solar radiation were tested. For comparison, the same composition of glass was melted into a conventional electric furnace. The use of CSP to produce glasses reduces the melting time by approximately 90%, with consequent energy savings. The increased CSP processing time results in more amorphous and thermally stable glasses. The results showed the viability of producing ecofriendly glasses in the SiO2–P2O5–CaO–K2O system, which could be used as matrix-based fertilizers.
2022
- Thermal behaviour and microstructural evolution of metakaolin and meta-halloysite-based geopolymer binders: a comparative study
[Articolo su rivista]
Kaze, C. R.; Nana, A.; Lecomte-Nana, G. L.; Deutou, J. G. N.; Kamseu, E.; Melo, U. C.; Andreola, F.; Leonelli, C.
abstract
Two calcined clays (halloysite and kaolinite clays at 700 °C) were used as solid precursors for geopolymer synthesis. This study compares the physicochemical properties of the both resulting geopolymer series heated at 200, 400, 600 and 800 °C. The end specimens were characterized using Optical Dilatometer, XRD, FTIR, MIP and SEM analyses. Results revealed that the flexural strengths were 18.10 and 21.74 MPa for meta-halloysite- and metakaolin-based geopolymers, respectively. After subjected to high temperatures, the flexural strength drastically decreased from 18.10 ± 1.06 to 6.7 ± 0.23 MPa and 21.74 ± 1.20 to 4.63 ± 0.24 MPa, respectively. The maximum shrinkage recorded on metakaolin and meta-halloysite-based geopolymers was 14 and 16% around 950 °C, respectively. The thermal conductivities decreased with increase in heating temperature from 0.78 to 0.19 Wm−1 K−1 and 0.96 to 0.26 Wm−1 K−1, respectively. This reduction is linked to the additional voids and microcracks that occurred within the geopolymer network. The cumulative intrusion in both geopolymers increased with increase in heating temperature up to 600 °C, leading to the degradation of geopolymer network that affected the mechanical strength evolution. Both synthesized geopolymer series are potential candidates for insulation materials or refractory applications.
2022
- Weathered bottom ash from municipal solid waste incineration: Alkaline activation for sustainable binders
[Articolo su rivista]
Maldonado-Alameda, A.; Giro-Paloma, J.; Andreola, F.; Barbieri, L.; Chimenos, J. M.; Lancellotti, I.
abstract
Alkali-activated binders (AABs) stand out as promising candidates to replace ordinary Portland cement (OPC) since waste can be used as raw material for their manufacture. This study addresses the environmental feasibility of using weathered bottom ash (WBA) and metakaolin (MK) as alkali-activated binder precursors (AA-WBA/MK). Different proportions of WBA and MK were mixed (100/0, 75/25, 50/50, 25/75, and 0/100 wt%) with a mixture of waterglass (WG) and NaOH 8 M as an alkaline activator solution. The effect of increasing MK content was assessed from a chemical, physical, mechanical, and environmental perspective. The results revealed the formation of secondary reaction products of C-(A)-S-H, (C,N)-A-S-H, and N-A-S-H gels. The compressive strength of AA-WBA/MK binders decreased (from 61.6 MPa to 12.6 MPa) as the MK content increased. The monolithic tank test validated the use of AA-WBA/MK binders for construction purposes, although with some restrictions due to their content in As, Sb, and V. Finally, the encapsulation efficiency and mechanical performance of AA-WBA/MK binders was enhanced as the curing period increased.
2021
- Cleaner design and production of lightweight aggregates (LWAs) to use in agronomic application
[Articolo su rivista]
Martinez-Garcia, C.; Andreola, F.; Lancellotti, I.; Farias, R. D.; Cotes-Palomino, M. T.; Barbieri, L.
abstract
This research focused on the obtainment of sustainable lightweight aggregates (LWAs) for agronomic application. The cleaner production is based on saving matter through the valorization of waste available in industry as a substitute of clays into the formulation of the lightweight aggregates (LWAs). Three different types of clays (white, black, and red) and alternative raw materials were blended. Cattle bone flour ash (CBA) and a fertilizer glass (FG) were used to introduce K and P into the mixture in amounts suitable for fertilizer application, and a sewage sludge from a brewery wastewater treatment plant was used as pore forming agent. For the production of the LWAs, we mixed different percentage of waste in two different clay mixtures, which were thermally treated at 1000 °C for 1 h. Technological parameters such as loose bulk and oven dry density, total porosity, water absorption capacity, pH, and electrical conductivity were determined to evaluate the potential use of LWAs as a growing media. Moreover, scanning electron microscopy (SEM) and mercury intrusion porosimetry (MIP) techniques were used, and leaching tests were performed to complete the samples’ characterization. The results indicated the potential for manufacturing highquality LWAs for the agronomic field by using energy-saving and matter-processing involving low temperatures with respect to the conventional process.
2021
- Comparison of Three Manufacturing Techniques for Sustainable Porous Clay Ceramics
[Articolo su rivista]
Andreola, Nora Maria; Lancellotti, Isabella; Sergi, Rachele; Cannillo, Valeria; Barbieri, Luisa
abstract
This study proposes different manufacturing techniques (manual pelletization, powder pressing, and “shell scaffold”) to obtain lightweight clay ceramics containing recovery raw materials. The sintering in an electrical furnace (1000 °C, 1 h processing time) was conducted by traditional firing from room temperature, for pressed and shell-scaffold samples, while the flash heating (i.e., samples directly put at 1000 °C) was used only for the pellets. The porous materials (porosity 40–80%), functionalized with nutrients (K and P) in amounts to confer the fertilizer capability, gave suitable results in terms of pH (6.7–8.15) and electrical conductivity (0.29–1.33 mS/cm). Thus, such materials can be considered as feasible lightweight clay ceramics, with a positive
effect on the soil. These findings permit us to hypothesize a potential use in green roofs or in agronomic applications.
2021
- Eco-compatible construction materials containing ceramic sludge and packaging glass cullet
[Articolo su rivista]
Andreola, F.; Lancellotti, I.; Pozzi, P.; Barbieri, L.
abstract
This research reports results of eco-compatible building material obtained without natural raw materials. A mixture of sludge from a ceramic wastewater treatment plant and glass cullet from the urban collection was used to obtain high sintered products suitable to be used as covering floor/wall tiles in buildings. The fired samples were tested by water absorption, linear shrinkage, apparent density, and mechanical and chemical properties. Satisfactory results were achieved from densification properties and SEM/XRD analyses showed a compact polycrystalline microstructure with albite and wollastonite embedded in the glassy phase, similar to other commercial glass-ceramics. Besides, the products were obtained with a reduction of 200◦ C with respect to the firing temperatures of commercial ones. Additionally, the realized materials were undergone to leaching test following Italian regulation to evaluate the mobility of hazardous ions present into the sludge. The data obtained verified that after thermal treatment the heavy metals were immobilized into the ceramic matrix without further environmental impact for the product use. The results of the research confirm that this valorization of matter using only residues produces glass ceramics high sintered suitable to be used as tile with technological properties similar or higher than commercial ones.
2021
- Influence of the synthetic calcium aluminate hydrate and the mixture of calcium aluminate and silicate hydrates on the compressive strengths and the microstructure of metakaolin-based geopolymer cements
[Articolo su rivista]
Moudio, A. M. N.; Tchakoute, H. K.; Ngnintedem, D. L. V.; Andreola, F.; Kamseu, E.; Nanseu-Njiki, C. P.; Leonelli, C.; Ruscher, C. H.
abstract
The main goal of this study is to investigate the effects of the calcium aluminate hydrate (CA04) and the mixture of calcium aluminate and silicate hydrates (CA04 + CS04) on the compressive strengths and the microstructure of metakaolin-based geopolymer cements. Bauxite, rice husk and eggshells were calcined and mixed in proper amounts to prepare CA04 and CS04. Metakaolin has been substituted by 0, 5, 10, 15 and 20 wt% of CA04, 10 and 20 wt% of (CA04 + CS04) in the formulation of geopolymer cements. The clay-like solid materials were characterized by measuring their compressive strengths, the crystalline and amorphous phases were monitored using the X-ray diffractometry analysis, their microstructures were investigated using the scanning electron microscope and mercury intrusion porosimetry and the functional groups were studied using the infrared spectroscopy. The compressive strengths of geopolymer cements containing 0, 5, 10, 15 and 20 wt% of CA04 are 49.50, 57.17, 63.59, 38.79 and 35.05 MPa, respectively. Those containing 10 and 20 wt% of (CA04 + CS04) are 40.59 and 51.19 MPa, respectively. The average pore diameters of geopolymer cements containing 0, 10 and 20 wt% of CA04 are 11.80, 10.10, 12.20 nm, respectively. Whereas the one containing 20 wt% of (CA04 + CS04) is 10.80 nm. It appears that geopolymer cement with 10 wt% of CA04 and 20 wt% of (CA04 + CS04) have higher compressive strengths and lower average pore diameters. It was found that 10 and 20 wt% of CA04 and (CA04 + CS04), respectively, could be used as additives for the preparation of geopolymer cements with higher strength development.
2021
- Microstructure and physico-chemical transformation of some common woods from Cameroon during drying
[Articolo su rivista]
Nouemsi Soubgui, E.; Tene Fongang, R. T.; Kamseu, E.; Oum Lissouck, R.; Andreola, F.; Boubakar, L.; Rossignol, S.; Leonelli, C.
abstract
The influence of drying on the microstructure, physical and chemical properties of some tropical wood species has been investigated using thermogravimetric analysis, differential scanning calorimetric (DSC), FTIR-ATR spectroscopy, mercury intrusion porosimetry (MIP) and environmental scanning electron microscopy (ESEM) analysis. Eleven tropical species were used in this study. Results showed that the common Cameroonian wood species can be grouped into three classes: Ga (lightwood) with cross-linking fibers having high volume of macropores, density in the range 0.2–0.4 g cm−3 and high lignin content; Gb (medium dense) with unidirectional fibers packing, density around 0.6 g cm−3 and Gc group showing high densification of unidirectional fibers and low porosity justifying the density > 0.8 g cm−3. Both the Gb an Gc groups have less significant lignin content. A relatively high rate of drying for Ga with respect to low drying rate for Gc was observed in direct relation with their porosity of ~ 72 Vol% and ~ 36 Vol%, respectively. LTF and WG showed similar cumulative pore volume (0.44 mL g−1) with different pore size distribution: 28% and 22% of macropores, 39% and 60% of mesopores and 33% and 18% micropores, respectively. Thermal analysis revealed that lightwoods have the highest amounts of residues and lower thermal stability of chemical components than dense woods. It has been found that the degradation process of hemicellulose, cellulose and lignin occurs mainly at about 200–300 °C, 300–350 °C and 350–500 °C, respectively. The group Ga with low drying rate, a low cycle of reproduction, a high volume of porosity together with large pore sizes appeared promising candidates for the design of ecological, environmental and sustainable management policy of wood transformation in developing countries and even worldwide.
2021
- Preliminary study on valorization of scraps from the extraction of volcanic minerals
[Articolo su rivista]
Piccolo, F.; Gallo, F.; Andreola, F.; Lancellotti, I.; Maggi, B.; Barbieri, L.
abstract
Powders < 3mm of pumice and lapillus (quarry scraps of national volcanic minerals) were employed in the tailoring and characterization (from the physical, chemical and mechanical point of view) of geo-polymers and lightweight aggregates. Geo-polymers were obtained at room temperature by substituting 70 - 80 wt% of metakaolin by volcanic scraps and employing an alkaline solution with a Na2SiO3/NaOH ratio from 0.8 to 1 for pumice and lapillus series, respectively. Within 24 h and in water, bulk specimens resulted with good integrity, with pH values around 9-11 and conductivity increasing over time, but less for the lapillus-containing sample richest in metakaolin indicating more compactness. The porosity, ranging around 32-33% for all the samples, increased up to 45% for the formulation based on 80% of lapillus. The best mechanical performance was achieved by lapillus samples: compressive strength in the range 35-38 MPa against 6-8 MPa of pumice ones. Lightweight aggregates were created by powder sintering at 1000 °C for 1 hour of 85 wt% of volcanic scraps and 15 wt% of spent coffee grounds used as pouring agent. Additional formulations were realized adding 50 wt% of nourishing mixture P and K-containing in the form of animal bone meal and vegetable biomass ashes. The specimens resulted porous and light (porosity around 60%), with good capacity of water retains, and, except in two cases, with neutral pH and conductivity values below 2 mS/cm, indicating a possible use for substrate (growing layer) in roof gardens, green roofs, house gardens, etc..
2021
- Sintering and phase formation of ceramics based on pre-treated municipal incinerator bottom ash
[Articolo su rivista]
Karamanov, Alexander; Karamanova, Emilia; Maccarini Schabbach, Luciana; Andreola, Nora Maria; Taurino, Rosa; Barbieri, Luisa
abstract
Ceramics, based on 60 wt% of municipal incinerator bottom ashes (MIBA) and 40 wt% of industrial clays, were prepared by using two fractions of pre-treated ashes (above and under 2 mm) and three different industrial clays.
The obtained six compositions with amounts of CaO from 12 to 14 wt%, with SiO2/Al2O3 ratio ranging from 3.5 to 1.6 and with Al2O3/CaO ratio - from 1.25 to 1.75 were investigated and characterized.
These compositions were located in the crystallization field of anorthite (CaO.Al2O3.2SiO2); the ceramics with high SiO2/Al2O3 ratio are near to the eutectic with SiO2, while with low ratio – closer to the anorthite stoichiometry.
The phase transformation and the subsequent melting were studied by non-isothermal DTA-TG analysis, while the densification process - by contactless optical dilatometry. Then, the optimal sintering temperatures and times were evaluated by isothermal dilatometric runs at different temperatures.
At high SiO2/Al2O3 ratio the sintering temperature is lower but the sintering range is very narrow. This behavior can be explained by the formation of too high amount of liquid phase at the eutectic temperature. On the contrary, at lower ratio, the sintering temperature increases but, notwithstanding the decrease of viscosity and shorter sintering time, the densification range becomes wider. This last result is a very important technological finding with a view to industrial transferability.
Additional tests performed demonstrated that a preliminary thermal treatment of ash with elevated residual organic phase is necessary, which leads to a lower firing shrinkage and to a shorter sintering time.
2021
- Synthesis and characterization of biochar-based geopolymer materials
[Articolo su rivista]
Piccolo, F.; Andreola, F.; Barbieri, L.; Lancellotti, I.
abstract
The aim of this research is to evaluate the possibility to realize alkali-activated materials exploiting biochar, a secondary raw material coming from pyrolysis/gasification processes, for environmental benefits, such as improvement of soil fertility and reduction of CO2 emissions into the atmosphere thanks to the carbon sink process where carbon dioxide is subtracted from the cycle of carbon. For the matrix of the geopolymers, a waste material derived from incinerator bottom ash was used and compared to pure metakaolin matrix. The materials obtained are lightweight and porous, with high water absorption capacity and moisture adsorption/desorption. BET analysis shows an increase in specific surface by increasing the biochar content and the biochar acts as a filler in the pores. From porosimetry analysis it is possible to follow the evolution of the curing process of the geopolymer prepared: specimens containing 70 wt% biochar after 28 and 90 days showed an increase in total Hg intrusion volume, pore area and total porosity but a decrease in the dimensions of pores. Due to the technical properties of materials containing biochar, they can be used in the future for a cleaner design of products in the field of sustainable construction for insulating panels or lightweight materials for houses and gardens in terraces and balconies.
2021
- Valorization of Al slag in the production of green ceramic tiles: Effect of experimental conditions on microstructure and crystalline phase composition
[Articolo su rivista]
Romero, M.; Martin, M. I.; Barbieri, L.; Andreola, F.; Lancellotti, I.; Lopez-Delgado, A.
abstract
This work reports the results of an investigation aimed at the development of sintered glass-ceramic tiles by the sinter-crystallization of mixtures composed of aluminum slag and reclaimed packaging glass. The thermal behaviors of mixtures incorporating 50 and 60 wt% Al slag were established by differential thermal analysis (DTA). Green compacts were sintered in a temperature range of 800°C-1050°C and then soaked for 10-60 minutes. The mineralogical characterizations of the sintered materials were obtained by X-ray diffraction (XRD). The achieved results indicated that the sintering of aluminum slag and packaging glass reclaimed led to a glass-ceramic material composed mainly of needle-like crystals of wollastonite (CaSiO3). The bloating of samples during firing was evaluated according to a Cougny predictive diagram. After initial observations and according to bending strength characterizations, sintered tiles prepared from aluminum slag and glassy sand are appropriate for floor pavement and wall covering.
2020
- Char valorization in construction materials
[Capitolo/Saggio]
Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella; Pozzi, Paolo; Vezzali, Vittorio
abstract
2020
- DESIGN AND CHARACTERIZATION OF CONTROLLED RELEASE PK FERTILIZERS FROM AGRO-RESIDUES
[Articolo su rivista]
Barbi, Silvia; Barbieri, Francesco; Andreola, Nora Maria; Lancellotti, Isabella; Martínez García, Carmen; Cotes Palomino, Teresa; Montorsi, Monia; Barbieri, Luisa
abstract
The aim of this study is to design and characterize a new controlled release fertilizers category by using valorization of residues
from agri-food, industrial and post consumers activities normally allocated into landfill disposal. The underlying strategy in
materials research fully agreed with the circular economy perspective and the more recent European legislation about critical raw
materials recovering. This study covers the development of lightweight aggregates, based on a local red clay (km 0 concept) and
pores former such as coffee grounds and brewery sludge. Functionalization has been performed with vegetable biomass and cattle
bone flour ashes, as received and after vitrification in a tailored fertilizer glass, containing high quantity of potassium and
phosphorous. Fully characterization by means of a multidisciplinary approach, including chemical, mineralogical, thermal, physical,
and plants growth in soils tests has been performed on starting and derived materials. Finally, growth test on basil’s plant have
demonstrated the beneficial effect of the aggregates designed and produced in this study in comparison with standard fertilizer
already on the market.
2020
- Environmental impact estimation of ceramic lightweight aggregates production starting from residues
[Articolo su rivista]
Barbieri, Luisa; Bigi, Alessandro; Andreola, Nora Maria; Lancelotti, Isabella; Ghermandi, Grazia; Teresa Cotes Palomino, Maria; Martínez García, Carmen
abstract
Within a circular economy approach, this study investigates the environmental impact of lightweight aggregates (LWAs) produced starting from different mixes of different clays with brewery sludge and cattle bone flour ash, used as poring and fertilizing agents, respectively. The environmental impact was evaluated by means of release tests, insulation capacity, carbon footprint and particulate matter emission during pellets firing. Release tests representative of LWAs realistic application showed very high release of phosphate and satisfactory release of potassium. The thermal insulation of the LWAs was tested by thermal imaging camera and resulted highly variable depending on the composition, with the mix containing cattle bone flour ash performing best. This latter composition leads also to the smallest CO2 equivalent emission, due to the calorific power of cattle bone flour ash, allowing lower consumption of fossil fuels during the LWA production. Finally, total particulate emissions during the thermal treatment resulted similar in terms of mass for all mixes, while differences in terms of particle morphology and composition occurred. Samples containing residues resulted with a quite good release behavior, carbon footprint and insulation properties, but higher emission of particles, particularly when glass is added.
2020
- Manufacturing of BaCe0.65Zr0.20Y0.15O3-δ-Ce0.85Gd0.15O2-δ structures by micro-extrusion 3D-printing
[Articolo su rivista]
Cannio, M.; Mortalo, C.; Prestianni, M.; Andreola, F.; Deambrosis, S. M.; Miorin, E.; Zin, V.; Boccaccini, D. N.; Romagnoli, M.
abstract
BaCe0.65Zr0.20Y0.15O3-δ-Ce0.85Gd0.15O2-δ (BCZ20Y15-GDC15) is currently one of the most studied composites for applications as dense ceramic membranes for H2 purification and membrane reactors. However, the efficiency of the structure represents a crucial issue to be solved for its practical uses. In this work the optimization of suitable slurries for the manufacturing of green asymmetric BCZ20Y15-GDC15 structures by μ-extrusion 3D-printing was investigated. The effect of the composition and rheological behavior on the stability and printability of the slurries was evaluated. Then, optimized slurries with different solid content were printed by a home-made μ-extrusion 3D printer through a step by step process: smooth and defect-free as-printed asymmetric structures with planar architecture were obtained.
2020
- Preliminary Study on Sustainable NPK Slow-Release Fertilizers Based on Byproducts and Leftovers: A Design-of-Experiment Approach
[Articolo su rivista]
Barbi, Silvia; Barbieri, Francesco; Andreola, Fernanda; Lancellotti, Isabella; Barbieri, Luisa; Montorsi, Monia
abstract
In this study, an organic nitrogen-based coating was developed based on black soldier fly (BSF) prepupae reared on
poultry dejections and deposited on ceramic lightweight aggregates (LWAs), containing phosphorous (P) and potassium (K) from
agroresidues, leading to a complete nitrogen, phosphorus, and potassium (NPK) fertilizer. To obtain a resistant coating with good
adhesion to LWAs, different plasticizing agents were tested (e.g., glycerol, cellulose, and polyethylene glycol). The coating
formulation was optimized through a design-of-experiment (DoE) approach to correlate the effect of each mixture component on
the coating’s performance. BSF biomass was characterized through chemical and thermal routes, as well as the final coated LWAs,
confirming their general agreement to fertilizer’s requirements. Release tests in static conditions highlighted the barrier action of the
coating, preventing uncontrolled release of potassium and phosphorus contained in the LWAs as well as the release of nitrogen after
21 days (near to 20%). Germination and growth tests indicated a valuable increase of the growth index, whereas the germination
process is limited by the coating barrier effect. This work proposes a new product in the field of slow-release fertilizers designed by
rational methodologies and innovative materials based on waste valorization, fully in agreement with a circular economy perspective
2020
- Preparation of low-cost nano and microcomposites from chicken eggshell, nano-silica and rice husk ash and their utilisations as additives for producing geopolymer cements
[Articolo su rivista]
Tchakoute, H. K.; Tchinda Mabah, D. E.; Henning Ruscher, C.; Kamseu, E.; Andreola, F.; Bignozzi, M. C.; Leonelli, C.
abstract
This work aims to prepare low-cost nanocomposite and microcomposite with lower molar ratio CaO/SiO2 (0.4). Nano-silica, rice husk ash and calcined chicken eggshell have been used as silica and calcium sources. Metakaolin has been separately replaced by 0, 10 and 20 wt% of each composite in order to study their behavior on the properties of geopolymers. The hardener used is sodium waterglass from rice husk ash. The surface area of nano-silica and rice husk ash was 54.40 and 4.08 m2/g, respectively. The cumulative volumes of the control geopolymer, the ones containing 10 wt% of microcomposite and nanocomposite are 119.71, 89.92 and 110.49 mm3/g, respectively. The compressive strength of the control specimen is around 64.02 MPa. The one using 10 wt% of microcomposite was 68.97 MPa. It drops to 42.88 MPa when metakaolin was replaced by 20 wt % of microcomposite. Whereas the one using 10 wt% of nanocomposite was 30.03 MPa and it decreases to 26.05 MPa when metakaolin was substituted by 20 wt% of nanocomposite. It can be concluded that 10 wt% of microcomposite could be mixed to metakaolin for strength development and nanocomposite does not recommend to use as an additive for producing high strength of geopolymer cements.
2020
- Production of Porous Poly(phospho-siloxo) Networks for Thermal Insulations Using Low-Value Calcium-Rich Wastes as Pore-Forming Agents
[Articolo su rivista]
Tchakoute, H. K.; Bewa, C. N.; Kesseng, N. A.; Ruscher, C. H.; Kamseu, E.; Andreola, F.; Ali, B. N.; Leonelli, C.
abstract
Abstract: This study focuses on the preparation of porous poly(phospho-siloxo) networks for thermal insulation applications using commercial calcium carbonate and calcium-rich wastes such as oyster shell, snail shell and eggshell powders as pore-forming agents. The control and porous poly(phospho-siloxo) networks were prepared by adding phosphoric acid (4 M) as a chemical ingredient to metakaolin containing 0 and 15 wt% of each foaming agents. The final products were monitored using the X-ray diffractometry, infrared spectroscopy, apparent density, absolute density, thermal conductivity, optical microscopy, scanning electron microscopy and mercury intrusion porosimetry. The results show that the thermal conductivity of the control and porous poly(phospho-siloxo) network from commercial calcium carbonate are 0.35 and 0.20 W/mK, respectively. They were higher compared to those from snail shell (0.17 W/mK), eggshell (0.15 W/mK) and oyster shell (0.14 W/mK). The cumulative pore volumes are 211.4, 365.5, 380.6, 389.7 and 393.3 mm3/g for the control and porous specimens from chicken eggshell, commercial calcium carbonate, snail shell and oyster shell powders, respectively. Their total porosity measured by mercury intrusion porosimeter are 30.9, 45.5, 46.0, 45.9 and 45.4%, respectively, whereas those calculated with apparent and true density measured by pycnometer are 34.48, 45.25, 52.74, 50.84 and 52.60%, respectively. The concentrated pore size diameter of the porous sample from eggshell is highest compared to the others. It can be seen that the total porosities measured by mercury intrusion porosimeter of porous specimens are nearly the same trend as well as the thermal conductivity. It was found that the low-value calcium-rich wastes could be used for producing porous poly(phospho-siloxos) networks which could be utilized for thermal insulation applications. Graphic Abstract: [Figure not available: see fulltext.].
2020
- The Environmental Friendly Route to Obtain Sodium Silicate Solution from Rice Husk Ash: A Comparative Study with Commercial Silicates Deflocculating Agents
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella
abstract
Sodium silicate solutions were synthesized treating Rice Husk Ash (RHA) with sodium hydroxide solutions at low molar concentrations (1–4 M). During the study the operative conditions were optimized. Raman spectroscopy was used to check the chemical nature of the silicates solutions obtained by comparison with commercial ones. The defocculating efciency of the synthesized solutions was checked by rheological measures on clay suspensions (solid content 60 and 65 wt%). Some fndings of the study permit to confrm that the extraction of SiO2 increases by increasing NaOH concentration. The alkaline attack (NaOH solution) at 1.5 and 2 M show the best results for SiO2/Na2O ratio close to 2, this ratio is widely used as defocculating agents in ceramic sector using commercial silicates. The 0.5wt% content resulted the optimum dosage for all additives. In particular, the viscosity values obtained using the silicates synthetized from RHA are lower than those corresponding to the commercial products. The defocculating capability behaves similar, or even better, than commercial ones. This valorization of matter from RHA allows the obtainment of high added value products that can play role of “green” substitutes of commercial ones.
2020
- The circular economy of agro and post‐consumer residues as raw materials for sustainable ceramics
[Articolo su rivista]
Andreola, Nora Maria; Lancellotti, Isabella; Manfredini, Tiziano; Barbieri, Luisa
abstract
The circular economy in the area of waste management implies their re‐use as a raw material in different production cycles. Both the qualitative and quantitative characteristics of the residues from the agro sector and those of the products of the ceramics sector make possible to think of a feasible application. This review will illustrate some examples of recycling of residues deriving from animal and vegetable sectors (and two post consume products, spent coffee grounds, and packaging glass cullet), studied by the authors, falling within the concept of urban and agricultural sustainable development. Not only the most traditional products such as glass‐ceramics, glazes, bricks, but also the most innovative lightweight aggregates for plant structures or in and out soil cultivation, as well as additives such as deflocculants for ceramic suspensions, which will be illustrated from the design/production, characterization, and comparison with commercial products.
2020
- Valorization of spent coffee grounds, biochar and other residues to produce lightweight clay ceramic aggregates suitable for nursery grapevine production
[Articolo su rivista]
Ronga, D.; Parisi, M.; Barbieri, L.; Lancellotti, I.; Andreola, F.; Bignami, C.
abstract
The valorization of agro-industrial by-products is one of the key strategies to improve agricultural sustainability. In the present study, spent coffee grounds and biochar were used as pore forming agents in the realization of lightweight clay ceramic aggregates that were used as sustainable fertilizers, in addition to tailored glass fertilizer containing phosphorous (P) and potassium (K) and nitrogen (N) synthetic fertilizer, for nursery grapevine production. The obtained fertilizers were assessed in a pot experiment for the fertilization of bare-rooted vines. Unfertilized (T0) and fertilized plants (T1, using NPK-containing commercial fertilizer) were used as controls. Plants fertilized by spent coffee grounds and spent coffee grounds + biochar-containing lightweight aggregates and added with 30 wt% of the above-mentioned glass and N fertilizers (T2 and T3, respectively) recorded higher values of plant height, shoot diameter, leaf and node numbers. Moreover, T2 treatment induced the highest chlorophyll content, shoot and root dry weights. The present study shows that lightweight clay ceramic aggregates containing spent coffee grounds and glass and N fertilizers can be used for nursery grapevine production, in turn improving the agricultural sustainability.
2019
- Formulation of Green Particulate Composites from PLA and PBS Matrix and Wastes Deriving from the Coffee Production
[Articolo su rivista]
Totaro, G.; Sisti, L.; Fiorini, M.; Lancellotti, I.; Andreola, N.; Saccani, A.
abstract
Particulate composites based on poly(lactic acid) and poly(butylene succinate) biopolymers have been formulated. Silver skin, the by-product derived from the roasting of coffee beans, has been used as a filler up to a 30 wt% of loading. The microstructure, crystallinity, thermal stability, mechanical properties and water absorption of the derived composites have been investigated. Data so far collected underline that a trade-off of the mechanical properties can be obtained by adding the filler, while the overall amount of crystallinity remains constant. Up to the highest filler content, moisture uptake follows a Fichian behaviour while the value of the contact angle is slightly increased by modification. Thus, silver skin, which actually is used for fuel or soil fertilization, finds here a different environmentally friendly valorization into the field of biocomposites.
2019
- Microstructural and mechanical properties of (Ca, Na)-poly(sialate-siloxo) from metakaolin as aluminosilicate and calcium silicate from precipitated silica and calcined chicken eggshell
[Articolo su rivista]
Tchuente, F. M.; Tchakoute, H. K.; Banenzoue, C.; Ruscher, C. H.; Kamseu, E.; Andreola, F.; Leonelli, C.
abstract
The aim of this work is to investigate the influence of the amorphous calcium silicate on the microstructural, physical and mechanical properties of (Ca, Na)-poly(sialate-siloxo) networks. The calcium silicate with molar ratio CaO/SiO 2 equal to 1.0 was prepared from the precipitated silica and calcined chicken eggshell. The X-ray patterns and infrared spectra of the synthesized calcium silicate indicate that it mainly constitutes of the amorphous calcium silicate hydrate. The X-ray patterns of geopolymer cements indicate that the prepared amorphous calcium silicate hydrate does not include in the network. The compressive strengths of the geopolymer mortars decrease from 28.92 to 12.03 MPa with increasing the replacement level of metakaolin (from 0 to 25% by mass). Whereas, the values of the apparent densities increase with increasing the replacement level of metakaolin. It seems that the amorphous calcium silicate hydrate in the structure of calcium silicate affects negatively the mechanical properties of the (Ca, Na)-poly(sialate-siloxo) network. The heterogeneous structure of geopolymer mortars containing 25% of calcium silicate could be related to the higher calcium content and the amorphous structure of calcium silicate hydrate. It was typically found that in the absence of significant levels of dissolved calcium, the precursors such as silicate and aluminate condense to form (Ca, Na)-poly(sialate-siloxo) networks. This implies the homogenous structure and the higher values of the compressive strengths of geopolymer mortars containing 0, 5, 10 and 15% of calcium silicate. Whereas those from the replacement level of metakaolin by 20 or 25% of calcium silicate contain significant levels of dissolved calcium and amorphous calcium silicate hydrate in their structure which hinder the formation of the precursors and therefore impede the formation of the (Ca, Na)-poly(sialate-siloxo) networks.
2019
- Results of the two-year rebaf project: How to exploit biomass from river maintenance
[Relazione in Atti di Convegno]
Pedrazzi, S.; Morselli, N.; Puglia, M.; Barbieri, L.; Lancellotti, I.; Andreola, F.; Malcevschi, A.; Giorgini, L.; Ceotto, E.; Tartarini, P.
abstract
This paper discusses activities and results of the REBAF project: a two-year Italian regional research project focused on the energy conversion of biomass residues from river, canals and basins maintenance activities. Innovative pathways for the exploitation of grass and woodsy biomasses were investigated. Gasification and pyrolysis are the key technologies for biomass conversion into energy. Woodsy biomass was tested as fuel in a small scale commercial gasification power plants that produce heat and power using a IC engine. A valuable by-product of the process was biochar. This was tested as soil improver in giant reed crop parcels and a sensible increase of dry biomass production was achieved in comparison with control parcels. The grass residues obtained from canals maintenance were carbonized in lab-scale pyrolyzer at a temperature of about 450 °C through the hot exhaust of the engine fueled by the gasifier. The pyrolysis gases were used directly in the gasifier in substitution of the gasifying agent. The residual carbon afterward the pyrolysis process was used as filler in cements, plasters and polyurethane panels increasing performance of these building materials.
2019
- Spent Coffee Grounds in the Production of Lightweight Clay Ceramic Aggregates in View of Urban and Agricultural Sustainable Development
[Articolo su rivista]
ANDREOLA, Nora Maria; Borghi, Alessandro; PEDRAZZI, Simone; ALLESINA, GIULIO; TARTARINI, Paolo; LANCELLOTTI, Isabella; BARBIERI, Luisa
abstract
This paper presents an innovative application for spent coffee grounds (SCGs) used as filler for the formulation of lightweight clay ceramic aggregates (LWA). LWA can be used for urban and agricultural purposes as a sustainable solution. Spent coffee grounds were tested as a pore forming agent partially acting as a replacement for red clay in material formulation before firing. Substitutions of 10, 15, and 20 wt.% of red clay were tested. The properties of lightweight aggregates with 15 wt.% of SCGs were improved using a specifically tailored fertilizer glass due to its low pH and conductivity within the soil tolerance range. Packaging glassy sand, cattle-bone flour ash, and potassium carbonate were mixed and melted in order to obtain this glass, which when added to the clayey batch functionalized the aggregates by phosphorus and potassium nutrients. The results (in particular, porosity and bulk density) show that the lightweight aggregates obtained have interesting properties for possible uses both in urban (e.g., green roofs as a drainage layer) and agricultural purposes. Moreover, pH and conductivity are in line with the Italian Standard regarding soil amendment (D.lgs. 75/2010). In addition, several leaching tests were performed in a solution containing 2 vol.% citric acid (C6H8O7) to evaluate the release capacity not only of nutrients (P and K)mbut also to check the presence and release of heavy metals, such as lead (Pb), that may come from the glassy precursor. The results obtained showed that nutrients are effciently released in 21 days (P = 87.73% and K = 25.74% of released percentage) and Pb release is under the standard threshold of 30 ppm.
2019
- Toxicological analysis of ceramic building materials – Tiles and glasses – Obtained from post-treated bottom ashes
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Queiroz Soares, Bárbara; Karamanov, Alexander; Schabbach, Luciana M.; Bernardin, Adriano M.; Pich, Claus T.
abstract
In Italy, the production of bottom ash from waste incineration was estimated as 1.6 million tons/year, corresponding to 30% of the total input waste. The bottom ash is mainly formed by SiO2, Al2O3, CaO,
Na2O and low amount of heavy metals, therefore it cannot be considered a ‘non-hazardous’ waste. In this context, the aim of this work was to determine the effectiveness of the sintering and vitrification techniques to turn bottom ash into an inert ceramic or glass matrix using toxicological tests. The bottom ash from a municipal solid waste facility was ground and used in ceramic tile and glass compositions. After sintering of the ceramic tiles and melting of the glass compositions, the samples were characterized by leachability and toxicological analyzes. Living organisms were used in the toxicological tests, Escherichia coli and Staphylococcus aureus (Agar Diffusion Test), Artemia sp. (Acute Toxicity Test) and Lactuca sativa (germination) and the results were compared with the plasmid DNA test. Regarding the leachability results, the ceramic tile samples showed a concentration of Cu slightly above the limit determined by the D.M. 5/4/2006 directive and, therefore, could not be considered an inert material. Regarding the toxicological tests, the bottom ash alone is mutagenic, but this effect is avoided once the ash is immobilized into the glasses and ceramic tiles, as demonstrated by the results reported in this study.
2018
- GASIFICATION OF BIOMASS FROM RIVER MAINTENANCE AND CHAR APPLICATION IN BUILDING MATERIALS PRODUCTION
[Articolo su rivista]
Vezzali, Vittorio; Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella; Pozzi, Paolo; Allesina, Giulio; Pedrazzi, Simone; Tartarini, Paolo
abstract
This paper exposes the research activities regarding REBAF (Energetic Recover of River Biomasses) project, focused on the maintenance operations self-sustainability of the Secchia river (Italy). Poplar was found as the most abundant and representative wood plant of Secchia riverbanks, with a good behavior during gasification process: from 1 hectare of maintenance every three year, it was possible to produce 23 MWh of electrical power and 31 MWh of thermal power. The biochar obtained was characterized and mixed with local red clay to create both lightweight aggregates (LWAs) for green roofs applications and bricks. Ashes coming from the gasifier cyclone were characterized and used to create bricks. The aims are the saving of raw materials and the obtaining of weight-lightened products with high porosity. Biochar and ashes were found to be suitable for this purpose given their organic carbonaceous nature, according to X-ray diffractometry, Loss on Ignition (LOI) and TG-DTA results. Application on LWAs by substituting 15%wt of the clay with biochar leads to a weight-lightening of the material. To optimize LWAs pH, spent coffee grounds (SCG) were added with proportion of 85% clay-15% biochar/SCG. A greater decrease in weight and pH values in the neutrality range were observed. Adding 20%wt biochar or ashes on bricks led to a significant reduction of materials bulk density (from 2 to 1.5 g/cm3) and the achievement of 40-45% porosity. With higher additions (until 40%wt) bulk density gets lower (1.2 g/cm3–1.3 g/cm3), but the material results weaker with a worst mechanical strength.
2018
- Investigation of the relationship between the condensed structure and the chemically bonded water content in the poly(sialate-siloxo) network
[Articolo su rivista]
Melele, Sorelle J. K.; Tchakouté, Hervé K.; Banenzoué, Charles; Kamseu, Elie; Rüscher, Claus H.; Andreola, Fernanda; Leonelli, Cristina
abstract
The main objective of this work was to investigate the relationship between the condensed structure and the chemically bonded water content in the metakaolin-based geopolymer network. The kaolin used in this work as an aluminosilicate source was transformed to metakaolin by calcination at 700 °C. The powder of the waste glass and the silica fume were used as silica sources for the synthesis of the hardeners, dissolving with caustic soda solution. The obtained hardeners were characterized by infrared spectroscopy and MAS-NMR 29Si. The metakaolin and the hardeners were used for producing geopolymers cements. The synthesized products were characterized by X-ray diffractometry, infrared spectroscopy, mercury intrusion porosimetry, scanning electron microscopy, MAS-NMR 29Si and 27Al, thermal analyses (TG and DSC) and compressive strength. The results show that the compressive strength of geopolymer cements using hardener from silica fume and the one from waste glass are 61.93 and 25.51 MPa, respectively. The microstructure (SEM observations) of geopolymer cements obtained using hardener from silica fume is homogeneous, compact and dense with an average pore diameter around 13 nm. Whereas, the one obtained using hardener from waste glass are heterogeneous and contains larger pores (with average pore diameter around 168 nm). MAS-NMR 29Si and 27Al results show that the specimen obtained using hardener from the silica fume contains more aluminum in four-fold coordination in its network than the ones using hardener from waste glass. This indicates a higher degree of crosslinking of poly(sialate-siloxo) chains which could lead to a smaller pore sizes and a higher water uptake in the structure of the sample. The amount of chemically bonded water contained in the network of geopolymer cements using hardeners from waste glass and silica fume were 6.82 and 11.23%, respectively, as determined from weight loss in the range 100–300 °C. All these results indicate that the higher content of chemically bonded water in the network of geopolymer cement obtained using hardener from silica fume is related to the much smaller average pore size diameter and the hydrophilic character of aluminum, which reveals obviously better mechanical and microstructural properties of the specimen. This could indicate here a higher degree of condensation using silica fume based hardener for geopolymerization.
2018
- PROCEDIMENTO PER UTILIZZARE CHAR DA GASSIFICAZIONE E/O PIROLISI CON ALTRI SCARTI INDUSTRIALI PER LA FORMULAZIONE DI MATERIALI ALLEGGERITI CON EFFETTO FERTILIZZANTE E DI MATERIALI POLIMERICI PER ISOLAMENTO TERMICO
[Brevetto]
Allesina, Giulio; Andreola, Fernanda; Tartarini, Paolo; Lancellotti, Isabella; Pedrazzi, Simone; Vezzali, Vittorio; Pozzi, Paolo; Barbieri, Luisa
abstract
L’invenzione si riferisce ad un procedimento per utilizzare char da gassificazione e/o pirolisi con altri scarti industriali per la formulazione di materiali, in particolare materiali alleggeriti con effetto fertilizzante e materiali polimerici per isolamento termico.
L’invenzione consiste nell’utilizzo di char ottenuto da processi di gassificazione/pirolisi di biomasse vegetali legnose all’interno di due tipologie di materiale:
1) Aggregati leggeri fertilizzanti, a base di argilla locale, ottenuti mediante trattamento termico. Il ruolo del char è inteso come agente porizzante mentre l’effetto fertilizzante è dato da un vetro appositamente preparato e ingegnerizzato, contenente fosforo e potassio. L’uso di questo vetro permette il rilascio controllato dei nutrienti nel tempo.
2) Pannelli per isolamento termico a base di polimeri (poliuretano) in campo edilizio dove il char funge da additivo per miglioramento delle proprietà termiche ed elettriche.
I vantaggi principali sono:
- Risparmio di materie prime naturali da cava
- Risparmio di materia prima «critica» come il fosforo
- Valorizzazione del Char in materiali per utilizzi agronomici ed edilizia sostenibile
- Ottenimento prodotti poliuretanici per isolamento edilizio dalle proprietà carbon sink
- Miglioramento proprietà termiche ed elettriche
2018
- Rice Husk Ash (RHA) Recycling in Brick Manufacture: Effects on Physical and Microstructural Properties
[Articolo su rivista]
Andreola, F.; Lancellotti, I.; Manfredini, T.; Bondioli, F.; Barbieri, L.
abstract
In this study RHA was used as silica source in the obtainment of clay bricks. Different compositions were prepared, substituting
the clays with diverse percentages of RHA (0–20 wt%) and requested water contents. The pastes obtained were extruded
in laboratory, dried and then fired in an industrial camera kiln. Technological tests were performed after drying (linear
shrinkage and naphtha absorption) and firing [(24-h immersion) water absorption, linear shrinkage, weight loss, average
flexural strength] steps. Besides, to analyze the effect on the microstructure and mineralogy, SEM/EDS and XRD analysis
of the fired bricks were performed. From the tests conducted it is possible to note that RHA content contributes to reduce
the linear shrinkage during drying while an opposite effect is observed for the water absorption. Regarding mechanical test,
the products containing up to 5 wt% of RHA are in according to the recommended values for roof. Bricks containing higher
amounts of RHA could be used in building manufacturing (light weighted faced load bearing walls) where moderate strengths
and penetration protection (porosity/permeability) are required. The carbon unburned present in the RHA contributes to
increase the final porosity and the weight loss of the bricks.
2018
- Role of ɣ-Al2O3 on the mechanical and microstructural properties of metakaolin-based geopolymer cements
[Articolo su rivista]
Tchakouté, Hervé K.; Kamseu, Elie; Banenzoué, Charles; Rüscher, Claus H.; Andreola, Fernanda; Tchamo, Claudia C. L.; Leonelli, Cristina
abstract
The main target of this work is to investigate the influence of ɣ-Al2O3 on the properties of metakaolin-based geopolymer cements. The kaolin used as starting material for producing geopolymer cements contains approximately 28 and 64% of gibbsite and kaolinite, respectively. This kaolin was transformed to metakaolins by calcination at 500, 550, 600, 650, and 700 °C for 1 h. Gibbsite contained in kaolin was transformed to γ-Al2O3 during the calcination process. The hardener was obtained by mixing commercial sodium silicate and sodium hydroxide solution (10 M) with a mass ratio sodium silicate/sodium hydroxide equal to 1.6:1. Geopolymer cements, GMK-500, GMK-550, GMK-600, GMK-650, and GMK-700, were obtained using the prepared hardener with a mass ratio hardener/metakaolin equal to 0.87:1. It could be seen that the specific surface area of metakaolins decreases with increasing the calcination temperature of kaolin owing to the formation of the particles of γ-Al2O3. The compressive strengths 18.21/29.14/36.61/36.51 increase in the course GMK-550/GMK-600/GMK-650/GMK-700. The X-ray patterns and micrograph images of geopolymer cements, GMK-600, GMK-650, and GMK-700, indicate the presence of γ-Al2O3 in their structure. It was typically found that γ-Al2O3 remains largely unaffected during the geopolymerisation, and therefore could act as an inert filler and reinforce the structure of geopolymer cements. [Figure not available: see fulltext.].
2017
- Influence of the molar concentration of phosphoric acid solution on the properties of metakaolin-phosphate-based geopolymer cements
[Articolo su rivista]
Tchakoute, H. K.; Ruscher, C. H.; Kamseu, E.; Andreola, F.; Leonelli, C.
abstract
Six different phosphoric acid solutions with molar concentrations 4, 6, 8, 10, 12 and 14 M were prepared by dilution of commercial phosphoric acid in distilled water. The obtained phosphoric acid solutions were used for producing metakaolin-phosphate-based geopolymer cements. These geopolymer cements were obtained by adding each fresh prepared phosphoric acid solution to metakaolin with a mass ratio phosphoric acid solution/metakaolin = 0.80. It was observed in the infrared spectra of phosphoric acid solutions 8, 10, 12 and 14 M, the absorption bands at 875–879 and 949–972 cm− 1 which are assigned to H2PO4−. The SEM images of geopolymer cements exhibit the presence of berlinite (AlPO4) which is dispersed in the matrix and contributes to enhancing the strength, whereas the geopolymer cements from phosphoric acid solution with 14 M are heterogeneous microstructures. The compressive strength of phosphate-based geopolymer cements was between 36.4 and 93.8 MPa; it increased with increasing the concentration of phosphoric acid solutions up to 10 M. It can be concluded that the most convenient concentration of phosphoric acid solution required for producing phosphate-based geopolymer cements with good mechanical properties is around 10 M.
2017
- New fired bricks based on municipal solid waste incinerator bottom ash
[Articolo su rivista]
Taurino, R.; Karamanova, E.; Barbieri, L.; Atanasova-Vladimirova, S.; Andreola, F.; Karamanov, A.
abstract
The main objective of this work was to study the sintering process and technological properties of new fired bricks based on high amount of post-treated municipal solid waste incinerator bottom ash and refractory clay. In addition, the effect of the minor addition of flux (Na2CO3) or reinforce (corundum) was also highlighted. Several methods were used to study the effect of compositions variations on the sintering process, structure and the mechanical characteristics of the test briquettes. Differential thermal analysis (TG/DTA) and dilatometry techniques were applied to study the thermal behaviour while scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy and high-temperature X-ray diffraction were used to elucidate the structure and the phase composition. The mechanical characteristics were estimated by micro-indentation, strength and various physical tests (porosity, linear shrinkage and water absorption, etc). The results highlight the possibility to use very high amount of municipal solid waste incinerator bottom ashes in the production of new fired bricks with good performances at all levels. It is also shown that the addition of additives managed the final properties, affecting the crystal phase formation, porosity and greatly the strength of the samples.
2017
- Structural Characterization of natural and processed zircons with X-rays and nuclear techniques
[Articolo su rivista]
Damonte, L.; Rivas, P.; Pasquevich, A.; Andreola, Nora Maria; Bondioli, F.; Ferrari, Anna Maria; Tositti, L.; Cinelli, G.
abstract
In ceramic industry, zircon sand is widely used in different applications because zirconia plays a role as common opacifying constituent. In particular, it is used as a basic component of glazes applied to ceramic tiles and sanitary ware as well as an opacifier in unglazed bulk porcelain stoneware. Natural zircon sands are the major source of zirconium minerals for industrial applications. In this paper, long, medium, and short range studies were conducted on zirconium minerals originated from Australia, South Africa, and United States of America using conventional and less conventional techniques (i.e., X-Ray Diffraction (XRD), Positron Annihilation Lifetime Spectroscopy (PALS), and Perturbed Angular Correlations (PAC)) in order to reveal the type and the extension of the regions that constitute the metamict state of zircon sands and the modifications therein produced as a consequence of the industrial milling process and the thermal treatment in the production line. Additionally, HPGe gamma-ray spectroscopy confirms the occurrence of significant levels of natural radioactivity responsible for metamictization in the investigated zircon samples. Results from XRD, PALS, and PAC analysis confirm that the metamict state of zircon is a dispersion of submicron disordered domains in a crystalline matrix of zircon.
2017
- Valorization of agro-industrial wastes in lightweight aggregates for agronomic use: Preliminary study
[Articolo su rivista]
Farias, Romina D.; García, Carmen Martínez; Palomino, Teresa Cotes; Andreola, Fernanda; Lancellotti, Isabella; Barbieri, Luisa
abstract
This research was focused on the valorization of agro industrial waste/by products available in the local industry with the kilometer zero (km 0) concept, as a replacement of virgin raw materials (clay) to elaborate lightweight aggregates (LWAS). The alternative raw materials were employed as pore forming agent, in order to reduce sintering temperature and energy consumption of the furnace. The three technical nutrients studied were provided for local food industries: sludge from wastewater treatment plant from brewery industry (SB), meat-bone meal (MBM) and corn cob (CC). These materials were characterized in terms of chemical (XRF and elemental analysis - CHNS) and mineralogical (XRD) composition, as well as their thermal behavior (TGA/DTA/DSC) and LOI. For the production of LWAS different percentage of waste/by product (0, 5, 10 and 15%) were mixed with three types of clays (white, black and red) in two different clay-based mixtures. With the addition of water were produced approximately spherical pellets and thermal treated at two different temperatures (900 and 1000°C) for 1 hour. Technological parameters such as bulk and absolute density, total porosity, water absorption capacity, pH, electrical conductivity and organic matter content were measured, to determine their potential use in agriculture. XRD and scanning electron microscope (SEM) were performed for the characterization of different samples. The results indicate the potential for manufacturing high quality lightweight aggregates for agronomic purposes, using relatively simple processing and low sintering temperature that contribute to the reduction of greenhouse gases to the atmosphere.
2016
- Production of cement blocks and new ceramic materials with high content of glass waste
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Lancellotti, Isabella; Taurino, Rosa; Leonelli, Cristina; Barbieri, Luisa
abstract
Virgin inorganic raw materials can be partially replaced by glass waste in order to reduce the environmental impact being its recycling a significant problem for municipalities worldwide. In Italy in 2013, approximately 1, 600, 000 tons of container glass have been collected but it has not been possible to recycle all of them in the glass melting process. The valorization, reuse and reclamation of glass waste as raw material in new cement and ceramic products are here proposed with the aim to convert it from an environmental and economic burden to a profitable, added-value resource in the formulation of new mixes. Several parameters, such as grinding, forming, firing, etc. have been studied and optimized to transform glass waste in an alternative raw material for hot and cold consolidation processes. Chemical, physical and mechanical properties of products have proved that there are new and real possibilities to use high amounts of glass waste for fired items (up to 80wt%) and for cold cement mixes (up to 75wt%).
2016
- Recycling of industrial wastes in ceramic manufacturing: State of art and glass case studies
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella; Leonelli, Cristina; Manfredini, Tiziano
abstract
Nowadays, ceramic tile are manufactured at zero emissions permitting to recycle all by-products and part of residues derived from depuration treatments (exhausted lime, glazing sludge and polishing sludge). In addition to this environmentally friendly tendency, in the last years an increasing number of scientific studies demonstrated the feasibility to use alternative raw materials in substitution of different component of the ternary clay-feldspar-quartz system. In the first part of the paper is reported the state of the art of industrial waste recycling in the ceramic sector, with the focus on review studies related to both ceramic tiles and bricks..In the second part of the work are reported two case studies conducted by the authors with the aim to formulate ceramic bodies using alternative raw materials. New tailored compositions were obtained replacing clays, flux and/or inert compounds (higher than 60. wt%) by scraps from packaging waste glass in tiles, and cathode ray tube glasses and packaging waste glass up to 20. wt% in the brick compositions.
2016
- Thermal approach to evaluate the sintering-crystallization ability in a nepheline-forsterite-based glass-ceramics
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella; Martín, M. I.; Rincòn, J. M. a.; Romero, M.
abstract
A glass in the SiO2–Al2O3–MgO–Na2O system was formulated using a non-conventional silica source and other pure raw materials. The thermal stability and crystallization mechanism have been studied by means of differential scanning calorimetry (DSC). Besides, the glass
ability to sintering–crystallization has been examined by optical dilatometry, a non-contact technique allowing the acquisition of dilatometric data in the viscoelastic temperature region. The experimental data were confirmed with theoretical equations. X-ray diffraction and field emission scanning electron microscopy were used to verify the crystallization study and electron scanning microscopy to examine the fired sample microstructures. The prevalent crystallization mechanism has been evaluated from different parameters derived from characteristic temperatures of non-isothermal DSC curves, namely the working range (DTTS), reduced glass transition temperature (Tgr), and the dissimilarity in crystallization temperature (DTp) between fine (< 63 micron) and coarse (fragment) glass samples.
2016
- Valorization of tyres waste pyrolysis residue in lightweight materials
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella
abstract
The aim of this study is to investigate an innovative way to utilize the char obtained from tyres pyrolysis, in order to realize light-weight materials for building. Pyrolysis residue, mixed with three types of waste glass, has been used as raw material to obtain lightweight materials, exploiting its capability to behave as foaming agent. The results demonstrate that the pyrolysis char is a good foaming agent for the mixtures 50/50 with glassy sand and packaging glass waste, thermal treated at 900°C for 45 minutes with degassing isotherm (500°C, 60 min). At these conditions, the samples obtained showed thermal behavior intermediate between an insulating commercially brick and a commercial refractory such as apparent density values lower than 1 g/cm3, compared to traditional ceramic material where density values are higher than 2 g/cm3. It can therefore be concluded that the materials produced have suitable properties for use in buildings as thermal and acoustic insulating.
2016
- Valorization of wastes, "end of waste" and by-products using hot and cold techniques
[Capitolo/Saggio]
Barbieri, L.; Andreola, F.; Taurino, R.; Ponzoni, C.; Manfredini, T.; Leonelli, C.; Lancellotti, I.
abstract
2016
- Valorization of wastes, “end of waste” and by-products using hot and cold techniques
[Capitolo/Saggio]
Barbieri, L.; Andreola, F.; Taurino, R.; Ponzoni, C.; Manfredini, T.; Leonelli, C.; Lancellotti, I.
abstract
The Framework Directive 2008/98/EC, implemented in Italy by Legislative Decree no. 205/2010, in addition to reporting specific criteria and targets, gave the impression of a new cultural attitude that offers the combination of sustainable use of resources coupled with sustainable management of waste. The adoption of the best available technologies for processing and valorization respects first of all the proximity of the production of the waste. The final aim is the increase of recycling practice to reduce the pressure on the demand for raw materials with a double effect: reuse valuable materials, that would otherwise end up as waste, and reduce energy consumption and emissions of greenhouse gases in the process of extraction and machining. By 2020, we must manage waste as a resource through those instruments and actions that will affect the diffusion of wastes separated collection, promotion of efficient and of high-quality recycling. Contemporary we will assist to the development of markets for the new raw materials obtained by waste recovery and energy recovery limited to the non-recyclable materials regardless of the decrease in per capita and the removal of illegal shipments as well as the landfill.
2015
- Design of glass foams with low environmental impact
[Articolo su rivista]
Mugoni, Consuelo; Montorsi, Monia; Siligardi, Cristina; Andreola, Nora Maria; Lancellotti, Isabella; Bernardo, Enrico; Barbieri, Luisa
abstract
Raw materials and their granulometry play a fundamental role in ceramic tile production especially as concern the mechanical properties of the final body. Aim of the present work is to
accurately investigate the role of the raw materials granulometry on the mechanical properties of a green porcelanized stoneware body. Correlations existing between the particle size distribution and flexural strength and Young's modulus of a standard gres mixture were investigated by using the Design of Experiments method. In particular, a starting mixture of clay, which composition was kept constant, feldspar and quartz, considered in two different granulometry, was used to define a statistical combination of components-mixture. After statistical analysis of the experimental data, regression models were calculated, relating the mechanical properties of the green ceramic body to the starting granulometry. Results obtained from the present study were considered for further investigations in order to produce gres with specific properties.
2015
- Effect of Additives on the Dispersion and Electrophoretic Deposition of Highly Diluted Enamel Suspensions
[Articolo su rivista]
Andreola, Nora Maria; Dignatici, M.; Chavez Valdez, A.; Siligardi, Cristina; Boccaccini, A. R.
abstract
This work examines the rheological behaviour of aqueous highly diluted suspensions (1 mass-%) to identify additives that may improve the application of vitreous enamel coatings by electrophoretic deposition (EPD). Slurries for EPD were prepared by ball milling frit glass in water with suspending agents. The effect of different additives in the solids concentration range from 0.2 to 2.0 mass-% on the rheological properties of coating solutions was investigated using rotational rheometry and zeta potential measurements. Different sedimentation times were observed for the tested dispersant, binder and coagulator additives. Densicer, an organic-inorganic mix additive, showed the best properties in terms of suspension stability. The high zeta potential measured with this product confirms its potential suitability as a suspension additive for vitreous enamel coatings applied by EPD.
2015
- Physical-mechanical properties of new green building materials based on glass waste
[Articolo su rivista]
Taurino, Rosa; Andreola, Nora Maria; Leonelli, Cristina; Manfredini, Tiziano; Gastaldi, Paolo; Barbieri, Luisa
abstract
Recently several innovative suggestions on how industrial wastes can be utilised in new products have been presented in literature, e.g. as filler or additives in concrete, incorporated in ceramic materials to produce glass-ceramics and pavement construction. In this work, metallurgical materials from secondary aluminium scrap processing and glass waste derived from treatments of packaging and fluorescent lamps were considered for fabrication of new ceramic materials using powder technology and sintering process.
The effect of composition and heat treatment temperature, on the sintering process and then final properties, were evaluated. The results showed that, with the proper firing temperature, lightweight ceramic materials containing high amount of glass waste and an innovative product resulting from the processing of secondary aluminum (ArgAlum) can be produced. The low water absorption (< 1%), low density (< 2 g/cm3) and the good flexural strength (16-20 MPa) associated to relatively low sintering temperatures obtained with the addition of ArgAlum can be considered as promising initial results to obtain new green building materials.
2015
- Transformation of the geopolymer gels to crystalline bonds in cold-setting refractory concretes: Pore evolution, mechanical strength and microstructure
[Articolo su rivista]
Kamseu, Elie; Djangang, Chantale; Veronesi, Paolo; Andreola, Nora Maria; Melo, Uphie Chinje; Sglavo, Vincenzo Mario; Leonelli, Cristina
abstract
Two K2O-MgO-Al2O3-SiO2 based geopolymer gels with bulk chemical composition corresponding to cordierite (Co) and 1:1 mullite-cordierite (MuCo) were successfully transformed to crystalline bonds in high temperature service of cold-setting made refractory concretes. Kyanite aggregates changed the flexural strength of the gels from11 to 28 MPa due to the development of good adhesive bonds. Under thermal cycles, up to 1250 °C, the cumulative pore volume remained at 0.09 mL/g, as fromthe absence of important densification/shrinkage. However, the behavior of the cumulative pore volume curves changed from that of a matrix with a wide range of distribution of pore sizes to that, of matrix, consisting of relatively coarse grains. The latter exhibits a rise at 10 μm as void spaces created around the contact points among the coarse kyanite grains and that at 0.054 μm as poreswithin the crystalline phases (cordierite, kalsilite, leucite,mullite, enstatite) formed. Themicrostructural observations confirmed the transformation of gel pores (size around 0.01 μm) to interparticle and intergranular pores due to the crystallization. The flexural strength of refractory concretes increased from28MPa to 40MPa in agreement with the increase in the elastic modulus from 9 to 30 GPa. The crystallization was enhanced by the MgO content (being important in Co compared to MuCo) and the kyanite concentration as particles of kyanite effectively acted as phase separation and nucleation sites
2015
- Valorization of inorganic waste, end of waste and by-product for ceramics
[Capitolo/Saggio]
Barbieri, Luisa; Andreola, Nora Maria; Taurino, Rosa; Lancellotti, Isabella; Leonelli, Cristina
abstract
Recycling and re-use of waste are economically attractive options for public and private actors due to widespread separate collection and the development of functional markets for secondary raw materials. The ceramic sector is particularly sensitive to this setting through re-entry into the production cycle of all by-products and partially amounts of residues derived from depuration treatment process. Besides, thanks to academic and industrial research results, there is the tendency to see different inorganic wastes, “end of wastes” and by-products as new good candidates.
In the present work, two case studies, one describing ceramics with high amount of glass waste and one ceramics with different kind of wastes, end-of-wastes and by-products, are reported with a commented list of technological and environmental benefits.
2014
- Environmental friendly management of CRT glass by foaming with waste egg shells, calcite or dolomite
[Articolo su rivista]
Fernandes, H. R.; Ferreira, D. D.; Andreola, Nora Maria; Lancellotti, Isabella; Barbieri, Luisa; Ferreira, J. M. F.
abstract
Panel (P) and funnel (F) glasses from Cathode Ray Tube (CRT) have been used to obtain glass foams by a simple and economic processing route, consisting of direct heating the glass powders at relatively low temperatures (650-750 °C) using different foaming agents (FA) such as egg shells, calcite, dolomite. Mixtures in different proportions of P and F glass powders were tested and the effects of composition and heat treatment temperature on the foaming behaviour were evaluated. Glass foams featuring apparent density and compressive strength values of 0.29 g/cm3 and 2.34 MPa, respectively, could be produced from a P/F ratio=1 with added 3 wt% of egg shells upon heat treating at 700 °C for 15 min. The P/F ratio was found to strongly influence the foaming behaviour and, consequently, the physical properties of the final foam glass. The relative performance of other foaming agents under a given set of experimental conditions revealed to be dependent on the type of glass (composition and thermal properties).
2014
- Preliminary studies on the valorization of animal flour ash for the obtainment of active glasses
[Articolo su rivista]
Barbieri, Luisa; Andreola, Nora Maria; Bellucci, Devis; Cannillo, Valeria; Lancellotti, Isabella; A., Lugari; Rincon, J. M. a.; M., Romero; Sola, Antonella
abstract
Animal flour ash, rich in phosphorous, calcium and alkaline oxides, has been used to formulate (i) controlled-release fertilizers, since they manage to release the nutrient elements (P, K) at a low rate, and (ii) bioactive glasses.
(i) Four formulations were tailored using different amounts of animal flour ash (35–48 wt%), potassium carbonate (10–25 wt%) and a fixed amount of glassy sand (40wt%) in order to get glasses and glass-ceramics. The materials were characterised from a chemical (XRF), crystallographic (XRD) and microstructural (SEM/EDS) point of view. Moreover, in order to check the ability to release the macro-and micro-nutrients, tests were conducted to determine the kinetics of glass dissolution in different media (2% citric acid solution, 1% hydrochloric acid solution and ammonium citrate solution). The results obtained allowed to confirm all samples show a very low solubility in water (less than 1%) and high values (>40%) of P, Ca, K and Na in the other media.
(ii) The rich content of phosphorous and calcium oxides makes the animal waste-derived ash a potential low-cost raw material to produce bioactive glasses. The analysis was focused on a bioactive glass, named BG_Ca, whose composition comes from the standard Bioglass® 45S5, got by increasing as much as possible the CaO content to combine a controlled behaviour during processing and a good apatite-forming ability in a simulated body fluid (SBF). This preliminary investigation shows that animal flour ash is a versatile material,which may be successfully used for several applications as various as the production of fertilisers and the preparation of bioactive glasses.
2014
- Sinter-crystallization in air and inert atmospheres of a glass from pre-treated municipal solid waste bottom ashes
[Articolo su rivista]
A., Karamanov; L., Maccarini Schabbach; E., Karamanova; Andreola, Nora Maria; Barbieri, Luisa; B., Ranguelov; G., Avdeev; Lancellotti, Isabella
abstract
Glass powders, obtained after vitrification and milling of iron-rich Municipal Solid Waste Bottom Ashes (MSWA),
were studied towards manufacture of sintered glass-ceramic material. The crystallization kinetics was investigated
both in air and argon atmospheres by non-isothermal Differential Thermal Analysis (DTA). The densification
behaviors at different temperatures were studied with optical dilatometry. The formed crystal phases were
evaluated with X-ray diffraction (XRD) and the microstructure of samples were observed by scanning electron
microscopy (SEM).
The investigated composition is characterized with a high crystallization trend and formation of pyroxene solid
solutions and melilite solid solutions. Due to additional nucleation process and lower viscosity (because of the
lack of Fe2+ oxidation) the phase formation in inert atmosphere is accelerated and is carried out at lower
temperature.
In the interval 800–900 °C the densification in both atmospheres is inhibited by the intensive phase formation.
However, after increasing the sintering temperature up to 1120–1130 °C secondary densification is carried out,
resulting in material with zero water absorption, low closed porosity and high crystallinity. Some decreasing of
sintering temperature and finer crystal structure are predicted at densification in inert atmosphere.
2013
- CRYSTALLISATION AND MICROSTRUCTURE OF NEPHELINE FORSTERITE GLASS-CERAMICS
[Articolo su rivista]
M. I., Martín; Andreola, Nora Maria; Barbieri, Luisa; Bondioli, Federica; Lancellotti, Isabella; Rincón, J. M. a.; M., Romero
abstract
This work presents the results of a study focused on the development of forsterite-nepheline glass-ceramic with the use of rice husk ash (RHA) as a silica source. The glass-ceramics were produced by a sintering process of a glassy frit formulated in the MgO-Al2O3-SiO2 base system with the addition of B2O3 and Na2O to facilitate the melting and pouring processes. The crystallisation study was carried out by depicting the TTT curve (Time-Temperature-Transformation). The mineralogical characterisation of the glass-ceramic materials was carried out using X-ray diffraction (XRD). The crystallisation activation energies were calculated by the Kissinger method. The results obtained show that nepheline (Na2O•Al2O3•SiO2) is the major crystalline phase in the temperature interval 700-950ºC and forsterite (2MgO•SiO2) predominates at temperatures above 950ºC. A study of the microstructure by scanning electron microscopy (SEM) allowed to establish the morphological evolution in both shape and spatial arrangement of the nepheline and forsterite crystals on heating.
2013
- Management of agricultural biomass wastes:Preliminary study on characterization and valorisation in clay matrix bricks
[Articolo su rivista]
Barbieri, Luisa; Andreola, Nora Maria; Lancellotti, Isabella; Taurino, Rosa
abstract
In this work the feasibility of using woody agricultural biomass wastes as grapes and cherrie sseeds,saw- dust,as pore forming agent,and sugar cane ash,as silica precursor,in bricks,were reported.
Sawdust and grapes and cherries seeds,thanks to their organic substances content,during their com- bustion,bring an energetic support in the bricks firingphase and act as pore formi ng agent.Usually the addition of this kind of waste is limited to 10 wt.%in order to reach an equilibrium between positive (weightand shrinkage decrease and porosity increase)and negative (increase of water absorption and mechanical resistance decrease)effects.The results show that grapes and cherries seeds,added in aper- centage of 5wt.%to abrick formulation,have better influencewith respect to the sawdust,maintaining the mechanical properties of the firedbrick (950C),showing modulu sof rupture around 21–23MPa with aweight reduction of 3–10%(respectto the standard one).Regarding the sugar cane ash,the addi- tion of 5wt.%improves the mechanical properties (modulusof rupture around 27 MPa)and no weight decrease is observed.These results confirmedthe role played by this kind of agricultural waste,which thanks to its high silica content (61wt.%)is capable to demonstrate afillerand plasticity reducing effect on the brick bodies.Tests carried out highlighted that the addition of these by-products (5wt.%)do not change negatively the main technological properties measured (waterabsorption,linear shrinkage,flex-ural resistance,etc.)and permit to hypothesize their use to obtain bricks with both insulating and higher mechanical properties using apore agent forming or silica carrier alternative raw materials,respectively.
2013
- TECHNICAL SOLUTIONS TO IMPROVE RECOVERY OF SCRAPS DERIVED FROM TREATING GLASS PACKAGING WASTE
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Davide, Giuranna; Lancellotti, Isabella; Taurino, Rosa
abstract
Nowadays, the Italian industry is constantly oriented on innovation of products and processes in order to
achieve a high level of economic and environmental sustainability. In this context, the waste management of Emilia
Romagna region is very active on the Italian territory, thanks to over 2 thousand green companies engaged in such activities. This philosophy must be understood as a strategy to address current and future challenges and to
strengthen our production system thanks to the support and commitment of citizens, consumers and entrepreneurs.
In 2010, in Italy about 32 million of municipal waste was produced, with a rate of separate collection of 35.3%. The waste glass collected in 2012 in Italy by separate collection of packaging waste amounted to approximately 1.6 million of tons of which 71% is sent to recovery (98% intended to glassworks, 2% to alternative recovery in ceramic or building industry (Co.Re.Ve, 2012). In Italy, the glass cullet is managed by Co.Re.Ve., the Italian Consortium for the recovery of packaging glass, since 1997. The cycle of collection and recovery of this glass can be implemented in 5 phases: collection of glass packaging in the container for recycling, withdrawal and transfer of glass cullet to the treatment plant, particle size selection and subdivision of cullet glass, obtainment of scrap suitable for the glassworks (maximum 0.068% of impurities (Co.Re.Ve., 2012), implementation of new packaging containing up to 90-95% of recycled glass. Specific treatments are performed on the glass cullet to obtain very low impurities values, such as manual sorting of pollutants, screening, separation of magnetic materials, suction of lightweight bodies and separation of non - magnetic bodies and opaque bodies are applied. Despite sophisticated equipment selection, total selection of "impure glass" is not guaranteed. In accordance with the Waste Framework Directive 98/2008/EC (landfill as a last form of disposal), the glass waste not sent to glassworks requires an alternative and innovative form of disposal.
Nowadays, in Italy, this fraction (contaminated by ceramic granules and high degree of organic pollutants and
coarse scraps) is collected and, in particularly in the North of Italy, treated by technological plant in order to obtain
secondary raw materials for both glassworks and ceramics. However, these treatments are very expansive and the
materials obtained (in particular glass or ceramic sand) have high economic value sometimes not economically sustainable.
2013
- Technological properties of glass-ceramic tiles obtained using rice husk ash as silica precursor
[Articolo su rivista]
Andreola, Nora Maria; M. I., Martín; Ferrari, Anna Maria; Lancellotti, Isabella; F., Bondioli; Rincón, J. M. a.; M., Romero; Barbieri, Luisa
abstract
This paper reports the results of a study focused on the obtainment of glass-ceramic by using rice husk ash (RHA) as silica precursor.
RHA is a by-product generated in biomass plants using rice husk as fuel for kilns or in the rice mills to generate steam for the parboiling
process. Worldwide, it is annually produced about 132 Mt of rice husk, which gives rise to a production of 33 Mt/year of RHA. Glassceramic
tiles were produced by a sinter-crystallization process using a glassy frit formulated in the MgO–Al2O3-SiO2 composition
system. The realized glass-ceramics were studied according to ISO rules for sintering and technological properties (water absorption,
apparent density, bending strength, Young’s modulus, deep abrasion, Mohs hardness). To complete the investigation crystalline phase
formation and microstructural characterization of the glass-ceramic materials was carried out using X-ray diffraction (XRD) and
scanning electron microscopy (SEM). Finally, chemical durability tests on parent glass and derived glass-ceramics were performed. The
results obtained showed that it is possible to use RHA to produce glass-ceramic tiles by a sinter-crystallization process, obtaining
nepheline (Na2O*Al2O3*SiO2) as main crystalline phase and forsterite (2MgO*SiO2) at 900 1C. Regarding technological features, the
sintered materials showed bending strength values and Mohs hardness higher with respect to commercial glass-ceramics like
NeopariesR. Other properties as water absorption (0.5%) allowed to classify these materials into the Group BIa characteristic of
high sintered ceramic tiles according to European Standard rule.
2013
- The use of egg shells to produce Cathode Ray Tube (CRT) glass foams
[Articolo su rivista]
Hugo R., Fernandes; Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella; Maria J., Pascual; José M. F., Ferreira
abstract
Cleaned Cathode Ray Tube (CRT) (panel and funnel) waste glasses produced from dismantling TV and PC colour kinescopes were used to prepare glass foams by a simple and economic processing route, consisting of a direct heating of glass powders at relatively low temperatures (600–800 1C). This study reports on the feasibility of producing glass foams using waste egg shells as an alternative calcium carbonate-based (95 wt%) foaming agent derived from food industry. The foaming process was found to depend on a combination of composition, processing temperature and mixture of raw materials (glass wastes). Hot stage microscopy (HSM), X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to characterize foams and evaluate the foaming ability and the sintering process. The experimental compositions allowed producing well sintered glass foams with suitable properties for some functional applications with environmental benefits such as: (1) reduced energy consumption because of the low heat treatment temperatures used; and (2) materials produced exclusively from residues.
2012
- Agricultural waste in the synthesis of coral ceramic pigment
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Bondioli, Federica
abstract
This work reports the results of an evaluation of the use of rice husk ash as the source of silica in thepreparation of coral ceramic pigments. ZrSiO4eFe2O3 inclusion pigments have been synthesized by solidstate reactions evaluating the effect of the mineralizer and both silica and iron oxide precursors on thereactivity of the system. The colour developed in the derived ceramic glazes has been compared with thecolour developed in comparative pigments prepared from pure SiO2.
2012
- Post-treated incinerator bottom ash as alternative raw material for ceramic manufacturing
[Articolo su rivista]
Schabbach, Luciana; Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella; E., Karamanova; B., Ranguelov; A., Karamanov
abstract
New ceramics based on 60 wt% of alternative raw material derived from post-treated municipal solid waste incinerator bottom ashes and 40 wt%of refractory clay were studied. The chemical analysis of the compositions was evaluated by ICP. The thermal and densification behavior of theceramic batches were evaluated by DTA-TG and dilatometry techniques, respectively. After that, the degree of sintering at different temperaturesand soaking times was evaluated in detail, measuring open and closed porosities, linear shrinkage and water absorption. The crystallinity at differenttemperatures (during heating and after cooling) and microstructure of the obtained samples were evaluated by high-temperature X-ray diffraction(HTXRD) and scanning electron microscopy (SEM), respectively. For these new ceramics, the experimental results highlighted sintering rangebetween 1190–1240 ◦C. In addition, the specimens demonstrated low water absorption and high crystallinity (with anorthite as main crystallinephase), leading to mechanical characteristics comparable to those of commercial ceramic products (bending strength > 40 MPa).
2012
- Valorization of MSWI bottom ash through ceramic glazing process: a new technology
[Articolo su rivista]
Schabbach, Luciana; Bolelli, Giovanni; Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella
abstract
-
2012
- WEEE: No waste anymore but secondary raw material
[Capitolo/Saggio]
Andreola, Nora Maria; Barbieri, Luisa; Cannio, Maria; Giovanardi, Roberto; Lancellotti, Isabella; Pozzi, Paolo; Soragni, Ercole
abstract
The management of Waste Electrical and Electronic Equipment (WEEE) is a topic of great interest, now being an integral part of the Italian D.Lgs. 151/2005. In order to protract life cycle of this waste, composed by glass, polymers and metals, a great effort is done to develop separation, reclamation, recycling and recovery techniques. This study reports the results achieved on the characterization of different materials constituting TV sets and computers, low environmental impact techniques of extraction and recovery of precious metals from electronic circuitry and the use of glassy components as secondary raw material in the ceramic field instead of virgin compounds.
2011
- Glass-ceramic materials of system MgO-Al2O3-SiO2 from rice husk ash
[Articolo su rivista]
M. I., Martìn; Rincòn, J. M. a.; Andreola, Nora Maria; Barbieri, Luisa; Bondioli, Federica; Lancellotti, Isabella; M., Romero
abstract
This wok shows the results of a valorisation study to use rice husk ash as raw material to develop glass-ceramic materials.An original glass has been formulated in the base system MgO-Al2O3-SiO2 with addition of B2O3 and Na2O to facilitate the melting and poring processes. Glass characterization was carried out by determining its chemical composition. Sintering behaviour has been examined by Hot Stage Microscopy (HSM). Thermal stability and crystallization mechanism have been studied by Differential Thermal Analysis (DTA). Mineralogy analyses of the glass-ceramic materials were carried out using X-ray Diffraction (XRD). Results show that it is possible to use ash rice husk to produce glass-ceramic materials by a sintercrystallizationprocess, with nepheline (Na2O·Al2O3·SiO2) as major crystalline phase in the temperature interval 700-950ºC and forsterite (2MgO·SiO2) at temperatures above 950ºC.
2011
- Integrated approach to establish the sinter-cristallization ability of glasses from secondary raw materials
[Articolo su rivista]
Schabbach, Luciana; Andreola, Nora Maria; E., Karamanova; Lancellotti, Isabella; A., Karamanov; Barbieri, Luisa
abstract
-
2011
- Minimization of Pb content in a ceramic glaze by reformulation the composition with secondary raw materials
[Articolo su rivista]
Schabbach, Luciana; Andreola, Nora Maria; Lancellotti, Isabella; Barbieri, Luisa
abstract
In this study a commercial ceramic glaze composed by both olivine (magnesium iron silicate, (Mg,Fe)2SiO4) and commercial frits, rich in lead (about 30 wt%), was reformulated by using secondary raw materials (CRT cone glass and municipal solid incinerator post-treatment bottom ashes before and after vitrification). The waste-based products were characterized and, compared to the standard glaze, showed better acid resistance, comparable aesthetic characteristics and slightly lower stainless resistance. Environmental benefits were obtained by saving natural raw material (olivine), by reducing lead percentage in the proposed formulations (from around 30 to 5 wt%), by energy saving (for the avoided use of commercial frits) and by reducing lead content in the new compositions.
2010
- End of life-materials: WEEE glass recovery in construction sector
[Relazione in Atti di Convegno]
Andreola, F.; Barbieri, L.; Lancellotti, I.
abstract
In this work was investigated the feasibility to use Waste Electrical and Electronic Equipment (WEEE) glasses in construction sector as secondary raw material. WEEE glasses were used in different percentages as a function of the product obtained: 30-40wt% for glaze formulations, about 40wt% for glass-ceramics and 5wt% in brick bodies. The laboratory and industrial scale up results demonstrated that it is possible to produce a glazed tile with a glaze containing fluorescent lamps glass instead of commercial ceramic frits. Glass-ceramics composed by nepheline ((Na,K) AlSiO 4), akermanite (Ca 2Mg(Si 2O 7)) and celsian (BaAl 2Si 2O 8) were obtained at low temperature and short time (T = 900°C and t = 60 min) with panel glass as component. Besides, small amounts of panel glass were added in brick bodies because this glass is suitable as fluxing agent only at high temperatures; at brick manufacturing temperatures (around 1000°C), the glass viscosity does not enough contribute to the sintering process.
2010
- New blended cement from polishing and glazing ceramic sludge
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella; M. C., Bignozzi; F., Sandrolini
abstract
Waste generated in ceramic tiles manufacturing is not usually recycled inside the productive plant, but rather disposed to landfill. This paper deals with ceramic residues from polishing and glazing processes, as constituents for innovative blended cements. New binders made up of 75% CEM I 52.5 R and 25% residues were chemically, physically, and mechanically characterized with reference to EN 197-1 requirements and the results compared with ordinary Portland cement. Mechanicalstrength development and microstructure of the relevant mortar have been investigated up to 90 days of curing, and the behavior of polishing and glazing residues as cement constituents is reported.
2010
- New polypropylene/glass composites: effect of glass fibers from cathode ray tubes on thermal and mechanical properties
[Articolo su rivista]
Pozzi, Paolo; Taurino, Rosa; Zanasi, Tania; Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella
abstract
This study investigated the feasibility of using fibers obtained by the recycling of end life cathode ray tubes glasses (EOL-CRT glass) as new filler for polypropylene material. The effects of these new fiberson the mechanical properties of plastic composites were studied. Fracture surfaces were investigatedby scanning electron microscopy. Based on the findings of this work, it appears evident that these newfibers can be used instead of commercial glass fibers providing good mechanical and thermal properties.Moreover the matrix modification in the hybrid composite led to better mechanical performances.
2010
- Recovery of glazing ceramic sludge in construction materials
[Relazione in Atti di Convegno]
Andreola, F.; Barbieri, L.; Lancellotti, I.
abstract
Ceramic glazing sludge deriving from the purification process of waste-water obtained by the glazing tile phase was mixed in equal proportion with glass cullet in order to obtain a high sintered product suitable to be used as floor/wall covering tiles. The characterization of fired samples includes the evaluation of both sintering parameters: water absorption, linear shrinkage and apparent density according to the ISO rules and sintering temperatures estimated by optical heating microscope. Satisfactory results were achieved from technological tests and SEM analysis showed a dense microstructure with crystalline phases similar to commercial glass-ceramic, identified by X ray diffraction. Besides, the obtainment of these products was achieved with energy saving due to the lower firing temperatures (about 1000°C) with respect to commercial products for floor/wall covering (about 1200°C).
2010
- Recycling electric arc furnace slag as unconventional component for building materials
[Relazione in Atti di Convegno]
Bignozzi, M. C.; Sandrolini, F.; Andreola, F.; Barbieri, L.; Lancellotti, I.
abstract
In this work a complete characterization of electric arc furnace slag (EAF-S) coming from an Italian steel production plant has been carried out with the goal to study if this type of waste is suitable to be used as cement constituent or aggregate for cement based materials. Exploiting the different chemical composition and grain size distribution of two types of EAF-S produced in different steps of the same industrial plant, mortar samples were prepared containing EAF-S as sand (from 10 up to 100%) or 25 wt% ordinary Portland cement replacement, respectively. Chemical and physical results agree with the requirements prescribed for cement and aggregate by European standards. Moreover, the mechanical performances determined on mortar samples seem promising, although an active participation of EAF-S in the hardening process has not been detected.
2010
- Recycling of screen glass into new traditional ceramics materials
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; F., Bondioli; Lancellotti, Isabella; Miselli, Paola; Ferrari, Anna Maria
abstract
The Cleaned cathode ray tube (CRT) glass comes from the dismantling plant of TV and PC color kinescopes and has been used to completely replace both feldspathic and inert components of a traditional ceramic body. Panel glass has been added (up to 20 wt%) to a mixture of two commercial ball clays in order to obtain laboratory tiles sintered at 12101C. Densification has been studied according to ISO rules, while sinterability has been estimated by optical dilatometry. The samples obtained showed main properties similar to commercial ceramic floor and/or wall tiles.
2010
- Sintered materials from incinerator secondary residues
[Relazione in Atti di Convegno]
Dzhantov, B.; Ranguelov, B.; Karamanova, E.; Andreola, F.; Barbieri, L.; Karamanov, A.
abstract
The possibility to obtain new eco-compatible building materials by milling, pressing and direct sintering of secondary raw materials (SRM) derived from a physical/mechanical treatment of municipal solid waste incinerator (MSWI) bottom ashes is discussed. The chemical compositions and particle size distribution of used SRM press powders were evaluated using XRF analysis and by laser granulometer, respectively. The thermal and densification behaviours were studied by non-isothermal DTA-TG and dilatometric techniques. The degrees of sintering, obtained at different temperatures of heat-treatment in the rage 1020 - 1140°C, were defined by measuring the linear shrinkage, the water absorption and the density variation (by gas pycnometer). The formed crystal phases were evaluated with X-ray Diffraction (XRD). The structure of the materials (surfaces and fractures) was observed by Scanning Electron Microscopy (SEM). With respect to the traditional building ceramics the new materials are characterised by totally different micro-structures and phase composition. The analysis of our results highlights also that the studied compositions are characterized by narrow sintering intervals, located between the solidus and liquidus temperatures of the main crystal phases. High crystallinity of obtained specimens, small water absorption and relatively low sintering temperatures can be considered as promising initial results to obtain low-cost building materials with elevate mechanical properties from direct densification of SRM from MSWI ashes. © SGEM2010 All Rights Reserved by the International Multidisciplinary Scientific GeoConference SGEM Published by STEF92 Technology Ltd.
2010
- The recycling of MSWI bottom ash in silicate based ceramic
[Articolo su rivista]
E., Rambaldi; L., Esposito; Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella; I., Vassura
abstract
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2010
- Use of incinerator bottom ash for frit production
[Articolo su rivista]
G., Barberio; P., Buttol; P., Masoni; S., Scalbi; Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella
abstract
This article presents the results of an experimental activityaimed at investigating the technical feasibility and the environmentalperformance of using municipal solid waste incinerationbottom ash to produce glass frit for ceramic glaze (glazefrit). The process includes an industrial pretreatment of bottomash that renders the material suitable for use in glazefrit production and allows recovery of aluminum and iron.The environmental performance of this treatment option isassessed with the life cycle assessment (LCA) methodology.The goal of the LCA study is to assess and compare the environmentalimpacts of two scenarios of end of life of bottomash from municipal solid waste incineration (MSWI): landfilldisposal (conventional scenario) and bottom ash recovery forglaze frit production (innovative scenario). The main results ofthe laboratory tests, industrial simulations, and LCA study arepresented and discussed, and the environmental advantages of recycling versus landfill disposal are highlighted.
2009
- Corrigendum to "Densification and crystallization of Ba-exchanged zeolite A powders" [Ceram. Int. 34 (2008) 543-549] (DOI:10.1016/j.ceramint.2006.12.010)
[Articolo su rivista]
Andreola, F.; Romagnoli, M.; Siligardi, C.; Manfredini, T.; Ferone, C.; Pansini, M.
abstract
2009
- Processing fly ash from coal burning power station in a variable radiofrequency field
[Relazione in Atti di Convegno]
Barbieri, L.; Lancellotti, I.; Andreola, F.; Cotradi, A.; Leonelli, C.; La Robina, M.
abstract
Experiments with fly ash obtained from a coal-burning power station in NSW, Australia, were conducted in the cold crucible facility at ANSTO using a 30kW variable frequency generator. The generator was configured as a standard Hartley oscillator with the tank capacitor able to vary from 110 pF to 4100 pF giving a frequency span of 5MHz to 18MHz. The applicator consisted of a coil with a water cooled base and top plate that formed an LC resonant cavity, which coupled to the RF generator by a single turn coil. A dark glass, confined inside the applicator, was formed by applying a high frequency electromagnetic field between two copper plates through a sample of fly ash. The temperatures reached were in excess of 1000 °C causing the powder to fuse into glass in a very brief period of a few minutes. The purpose of this experiment was to verify if dielectric and/or induction heating could melt the fly ash in a more rapid manner than conventional (resistive/joule) heating.
2009
- Thermal treatments for the recovery of value added materials
[Capitolo/Saggio]
Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella
abstract
The techniques able to incorporate wastes can be divided between cold and hot techniques. In the first group falls stabilization/solidification by both inorganic (cement, lime, clay) and organic (thermoplastic materials, macroencapsulating compounds, asphalts, polymers) reagents. The second group comprises vitrification, devitrification, and sintering. Thermal treatments, which might speed up by the use of electromagnetic irradiation, present the advantage to fix the residue with chemical bonds, changing the microstructure or morphology from hazardous to harmless.
2009
- Valorizzazione di Scarti Agroalimentari nel Settore dei Laterizi
[Articolo su rivista]
Bondioli, Federica; Barbieri, Luisa; Andreola, Nora Maria; N., Bagnoli
abstract
Il presente studio è incentrato sulla valorizzazione degli scarti dell’industria agroalimentare, ed in particolare della filiera cerealicola, costituiti principalmente da scarti di raffinazione, di pulitura, bucce e semi, il cui utilizzo principale attualmente è come biomasse (biopower)
2009
- WEEE Problems and Perspectives: The Case of Glass Recovery in the Ceramic Industry
[Capitolo/Saggio]
Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella
abstract
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2008
- Densification and crystallization of Ba-exchanged zeolite A powders
[Articolo su rivista]
Andreola, Nora Maria; Romagnoli, Marcello; Siligardi, Cristina; Manfredini, Tiziano; C., Ferone; M., Pansini
abstract
The effect of thermal treatment, Na content and mineralizer ion on the sintering process of Ba-exchanged zeolite A on the zeolite ! celsianthermal transformation are investigated. The powder samples containing different amounts of Na+ and Li+ were pressed at 30 MPa and thermallytreated at temperatures from 1000 to 1400 8C for times up to 5 h and subsequently were characterized by room temperature X-ray diffraction and byscanning electron microscopy. Increasing the Na residual content in the Ba-zeolite A samples improves the sintering process, even if the highest Nacontent appears to inhibit the zeolite! celsian transformation, since a new crystalline phase appears at the highest temperature. Moreover, theporosity of all samples thermally treated is quite high. Finally the manufacture of pressed samples allowed lower temperatures and times to be usedto obtain the transformation zeolite Ba-A ! monoclinic celsian, which suggests it is a potential method to prepare celsian low temperaturerefractory materials. At last an ANOVA analysis was carried out to identify the independent parameters from a statistical point of view.
2008
- High temperature techniques for chemical incorporation of wastes aimed to the obtainment of re-products
[Relazione in Atti di Convegno]
Andreola, F.; Barbieri, L.; Lancellotti, I.; Morselli, L.; Passarini, F.; Vassura, I.
abstract
The techniques able to incorporate wastes by means of a heat treatment present the advantage to fix the residue with chemical bonds. Among these techniques there are vitrification and sintering which are characterised by different operating temperatures in the range of 950-1500°C and the involved raw materials develop silicatic crystalline phases and glassy matrices capable to immobilize heavy metal contents in the waste matrix. In this work incinerator bottom ash, polishing and glazing ceramic sludges have undergone to thermal treatments in order to valorise the waste as secondary raw material for the obtainment of re-products. The chemical efficiency of the process adopted has been evaluated by comparing the results of release tests applied to the as-received wastes and to the thermally treated materials in order to verify the effectiveness of the different matrices to fix the waste components.
2008
- New Clay Based Ceramics Using Cathode Ray Tube (CRT) Glass as Secondary Raw Material
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Barbieri, Luisa; F., Bondioli; Ferrari, Anna Maria; Lancellotti, Isabella; Miselli, Paola
abstract
Cleaned panel glass was added in different percentages (5-20 wt%) to a mixture of two commercial ball clays in order to formulate new clay based ceramics replacing completely both fluxing and inert components of a traditional ceramic body. The samples obtained in laboratory were fired in industrial cycle (Tmax 1200oC for 40 min). The samples obtained were characterized from densification, microstructural, mechanical and aesthetical point of view. From the results achieved samples tiles, containing up to 15 wt% of panel glass, could be classified into BIa group (WA<0.5%) (UNI EN 14411 all.G) corresponding to impervious tiles used mainly for floor or wall covering.
2008
- Recovery of precious metals from electronic scraps
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Barbieri, Luisa; Giovanardi, Roberto; Lancellotti, Isabella; Soragni, Ercole
abstract
Recovery of precious metals (PMs) is a present topic, as they are used almost in every electronicelectric device. Gold is the second PM in order of consumption (following silver) and it is almost ubiquitary in electronics where it mainly finds application to produce bonding wires in integrated circuits and as a coating for contacts and connectors. Given this, discontinued electronic and, with a minor role, electric devices may represent a primary source of PMs as gold mines or jewelery wastes. At present the recovery of gold from such waste is generally accomplished by two strategies: by oxidative thermal treatment followed by metallurgical or chemical processes or by cyanide chemical etching; both techniques do not represent the optimum as the first one deserves a great amount of energy and non-combustible pollutant slag and fumes are produced, while the second procedure comports the use of a highly pollutant agent as cyanide. The aim of this work is the characterization of different electronics scraps to evaluate the gold concentration, and the selective recovery of this metal using enviromentally-friendly techniques. In particular, a new process was developed in order to overcome such environmental and efficiency issues. The process reaches the goal of detach the gold film from the substrate by selective leaching of the supporting metal.
2008
- Recycling of CRT panel glass as fluxing agent in the porcelain stoneware tile production
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; E., Karamanova; Lancellotti, Isabella; M., Pelino
abstract
In the present work, the feasibility to substitute feldspar raw material in a porcelain stoneware body with Panel Cathode Ray Tube (CRT) glasswas investigated. A standard batch and a composition, where 35 wt.% Na-feldspar was substituted by CRT glass, were sintered at differenttemperatures in the range of 1000–1250 8C. The degree of the densification was studied by evaluation of the closed and total porosity, while thesintering rate was estimated by non-isothermal dilatometric measures. The variation of the crystalline phase composition was evaluated by XRDanalysis. From the preliminary study other ceramic samples with different percentages of CRT glass (i.e. 2.5, 5 and 10 wt.%) were prepared andfired in industrial kiln. The sintering parameters, the microstructure and the mechanical properties were measured and compared with the standardcomposition.
2008
- Reuse of incinerator bottom and fly ashes to obtain glassy materials
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Hreglich, S; Lancellotti, Isabella; Morselli, L; Passarini, F; Vassura, I.
abstract
Bottom and fly ashes coming from the urban wastes incineration represent a by-product nowadays landfilled. By mixing different amount of these residues with others inert materials, such as glass cullet and feldspar waste, two vitrifiable mixtures are tailored. Glasses, obtained by means of vitrification process, are chemically stable with low leachability of contaminants and show comparable properties to those of commercial soda lime glasses. Moreover, from the thermal and mechanical characterization the tendency of these glasses to crystallise, for their transformation into glass-ceramic materials, has been evidenced.
2008
- Room-Temperature Degradation of t-Zr(Pr)O2 in an Aqueous Suspension Revealed by Perturbed Angular Correlations
[Articolo su rivista]
Caracoche, Mc; MARTINEZ J., A; RIVAS P., C; Andreola, Nora Maria; F., Bondioli; Ferrari, Anna Maria; Manfredini, Tiziano
abstract
This paper deals with the phase stability of an aqueous suspension of tetragonal Zr0.9Pr0.1O2 (20 wt%/vol%) at room temperature as a function of the aging time. The suspension is investigated in situ using the highly localized Perturbed Angular Correlations technique. The results indicate that an almost fully reversible degradation process toward monoclinic zirconia takes place through a first-order reaction of rate constant k = 0.7-1day. Two successive diffusion mechanisms are observed that are interpreted as OH ions’ migration in the grain surface and then, as proton defects’ diffusion into the bulk.
2008
- Synthesis of chromium containing pigments from chromium galvanic sludges
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; F., Bondioli; Cannio, Maria; Ferrari, Anna Maria; Lancellotti, Isabella
abstract
In this work the screening results of the scientific activity conducted on laboratory scale to valorise chromium (III) contained in the galvanic sludge as chromium precursor for ceramic pigments are reported. The valorisation of this waste as a secondary raw material (SRM) is obtained by achievement of thermal and chemical stable crystal structures able to colour ceramic material. Two different pigments pink CaCr0.04Sn0.97SiO5 and green Ca3Cr2(SiO4)3 were synthesized by solid-state reactions using dried Cr sludge as chromium oxide precursor. The obtained pigments were characterized by X-ray diffraction and SEM analysis. Furhermore the color developed in a suitable ceramic glaze was investigated in comparison with the color developed by the pigments prepared from pure Cr2O3. The characterization carried out corroborates the thermal and chemical stability of the synthesized pigments and, especially for the Cr-Sn pink pigment, the powders develop an intense color that is very similar to the color developed by the pigments obtained starting from pure Cr2O3.
2007
- ANALISI LCA DEL QUARZO VENTILATO
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; F., Bondioli; Ferrari, Anna Maria; Lancellotti, Isabella; P., Neri
abstract
-
2007
- CRT glass state of the art. A case study: Recycling in ceramic glazes
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Corradi, Anna; Lancellotti, Isabella
abstract
The management of electrical and electronic equipment waste (WEEE) is a significant problem of industrialized countries, in the last decades it has been noticed an appreciable increase of this residue, consisting of about 80% of television sets and cornputers containing end of life (EOL) cathode ray tubes (CRT). Specific technologies permit to dismantle the kinescope, obtaining different glasses with high quality level and specific chemical compositions. The presence of dangerous elements makes critical the re-use in many fields of application. The present work proposes the feasibility of CRT glass recycling in ceramic field using it into a base glaze formulation as substitute of ceramic frits. The study was conducted in two phases, laboratory scale in order to study the suitable glaze formulation and semi-industrial scale with the technological support of an Italian ceramic glaze producer. The glazes obtained have aesthetic and mechanical properties extremely similar to the standard ones. (c) 2006 Elsevier Ltd. All rights reserved.
2007
- Effect of rice husk ash (RHA) in the synthesis of (Pr,Zr)SiO4 ceramic pigment
[Articolo su rivista]
F., Bondioli; Andreola, Nora Maria; Barbieri, Luisa; Manfredini, Tiziano; Ferrari, Anna Maria
abstract
In this work the screening results of the scientific activity conducted on the possibility to use rice husk ash as silica precursor for ceramic pigments are reported. Ceramic pigments were synthesized by solid-state reactions and the color developed in a suitable ceramic glaze was investigated in comparison with the color developed by the pigments prepared from pure SiO2.
2007
- Esempi di utilizzo in impasti di gres porcellanato delle argille plastiche SC1, SC2 e SC3 prodotte dalla Sarda Silicati
[Articolo su rivista]
Carbonchi, C.; Danasino, P.; Andreola, F.; Siligardi, C.
abstract
2007
- Mixture of deflocculants: A systematic approach
[Articolo su rivista]
Romagnoli, Marcello; Andreola, Nora Maria
abstract
In the production of ceramic tiles, during wet grinding, chemical additives are normally used to increase the solid loading of the suspensions. Commonly, mixtures of organic and inorganic chemical additives are used to reduce viscosity and costs. In literature, only few papers consider the combined effect of two or more deflocculants and a modest knowledge has developed on possible competitive or synergic interactions among them. The most common rheological additives show different behaviour depending on the clay. With mixture design it is possible to define mathematical models by means of which it is possible to engineer the rheological behaviour of a suspension. (c) 2006 Elsevier Ltd. All rights reserved.
2007
- RELEASE OF IONS FROM KAOLINITE DISPERSED IN DEFLOCCULANT SOLUTIONS.
[Articolo su rivista]
Andreola, Nora Maria; Castellini, Elena; Lusvardi, Gigliola; Menabue, Ledi; Romagnoli, Marcello
abstract
Chem. investigations have been performed on deflocculated suspensions of kaolinite previously treated with two widely employed dispersants: sodium hexametaphosphate (NaHMP) and sodium disilicate (NaDIS). F. Andreola et al. (2006) showed remarkable differences in the rheol. behavior between untreated and treated samples. The release of ions by kaolinite dispersed in deflocculant solns. results strongly affected by the nature of the treatment. The chem. anal. of the soln. phase sepd. from the suspensions of treated and untreated kaolinite provides relevant information about the deflocculation mechanism of HMP and DIS and gives reason of the obsd. differences in the rheol. responses.
2007
- Recycling of EOL CRT glass into ceramic glaze formulations and its environmental impact by LCA approach
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Corradi, Anna; Ferrari, Anna Maria; Lancellotti, Isabella; P., Neri
abstract
AbstractBackground, Aims and Scope The interest in recycling materials at the end of their life is growing in the industry in general. As regards the Wastes of Electrical and Electronic Equipment (WEEE), an appreciable increase of these materials has been noticed in the last decades, 117 · 103 tons of WEEE have been produced in Italy in 2002 according to Ecohitech [1] and the increase in this kind of waste is three times higher than that of the municipal waste according to the FISE ASSOAMBIENTE report [2]. Within WEEE, End-of-Life Cathode Ray Tube (EOL CRT) glass, the main part of TV sets and PC monitors, is here analysed using both a technical approach to establish a possible reuse of the glass in a open-loop recycling field (ceramic industry) and a methodology (LCA) capable of providing environmental evaluations. Methods The technological characterization was performed by chemical resistance tests (UNI EN ISO 10545-13), staining tests (UNI EN ISO 10545-14) with blue methylene and potassium permanganate (KMnO4), and surface abrasion tests (UNI EN ISO 10545-7). The LCA study was conducted using the SimaPro 5.0 software and Eco-Indicator 99 as an evaluation method. Results and Discussion The good technical results, reached by using cleaned EOL CRT panel glass inside a ceramic glaze formulation instead of a commercial frit, are supported by the environmental impact evaluation, which shows a decrease of the overall potential damage (measured in Points) of 36% and, in particular, a reduction of 53% in ‘Human health’, 31% in ‘Eco-system quality’ and 24% in ‘Resources’. Conclusions This study has demonstrated that this new, open-loop recycling strategy for the CRT glass significantly reduces the environmental impact of the ceramic glaze production process. In fact, in all damage categories examined in this study, there is a minor impact. An improvement is evident in the respiratory inorganics sub-category related to the lowering of dusts mainly and to a lesser amount with NOx and SOx in the climate change sub-category, due mainly to the reduction of CO2 emission correlated to the avoided combustion of the mixture which feeds melting furnaces in the frit production. Thus, the damage decrease in ‘Ecosystem quality’ is prevalently due to the lower NOx emissions by the kilns in the frit production that is evident in the acidification/eutrophication sub-category. Finally, the significant saving in the ‘Resource’ category is principally linked to the fossil fuels sub-category, thanks to the methane saving which stokes the melting furnaces. Perspectives Furthermore, the decrease in CO2 emission (94.4%) evident in the climate change sub-category is a very important topic because it is in line with the Kyoto protocol (1997), where significant efforts have been exerted for the reduction of the green house gases emission, notably CO2. The CO2 emission is correlated to the combustion of the mixture which feeds melting kilns in the frit production, therefore the recycling of secondary raw materials, already in a glass state, can reduce the emissions of this gas. This reduction can be termed as environmental credit and it is an example of an allocation of environmental loads in a open-loop recycling, where waste from one industrial system are used as raw materials in another product system.
2007
- Recycling of crt waste glass in porcelain stoneware production
[Relazione in Atti di Convegno]
Karamanova, E.; Andreola, F.; Lancellotti, I.; Barbieri, L.; Karamanov, A.
abstract
The feasibility to substitute feldspar raw materials in a porcelain stoneware body with waste Cathode Ray Tube (CRT) glass was investigated. Various compositions, containing different percentages of feldspars and CRT glass, were compared. The densification process was studied by non-isothermal dilatometry and the degree of sintering was evaluated by pycnometric techniques. The structure and phase composition of the final ceramics were studied by SEM and XRD, respectively. The technological parameters and the mechanical properties were also measured and compared with a standard plant composition. It was highlighted that the addition of low viscous CRT glass gives a possibility to reduce the total amount of fluxes in the batch and to decrease the cost. Ceramics with characteristics, similar to the plan composition, were obtained by replacement of 5-14 % feldspars with 5-10 % CRT glass.
2007
- Valorization of Italian clay added bentonites for porcelain stoneware bodies.Study of the rheological behaviour and mechanical properties
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Siligardi, Cristina; Manfredini, Tiziano; C., Carbonchi; P., Danasino
abstract
This paper present the results obtained using a clayfrom Sardinia island, Italy, added with 10 wt% ofdifferent bentonites available on Italian territory inorder to obtain a decreasing of the body costs. Twoserie of bodies was prepared a first serie substitutingcompletely Germany clay and partially Ukraine clay(5wt%), a second serie substituting completely theUkraine clay into a porcelain stoneware body.Rheological measures were carried out on thesuspensions prepared in order to verify the effect of thebentonites presence on the shear and time dependence.The fired specimens were characterized across thetechnological parameters, mechanical and aestheticalproperties and compared with a standard/industrialcomposition.
2006
- Effect of sodium hexametaphosphate and ageing on the rheological behaviour of kaolin dispersions
[Articolo su rivista]
Andreola, Nora Maria; J. M. F., Ferreira; S., Olhero; Romagnoli, Marcello; Castellini, Elena
abstract
Concentrated dispersions (35% v, v) of ceramic grade kaolin dispersed with sodium hexametaphosphate (NaHMP) were prepared at three different experimental conditions: in distilled water at 30 and 60 degrees C, and in a 5 * 10(-3) M Ca(NO3)(2)(.)4H(2)O solution, at 30 degrees C. The dispersions were kept at constant temperatures for different ageing times (2, 4, 6, 18, 24, 48 h). After each ageing period they were submitted to rheological measurements and centrifuged to measure the concentration of HMP- ion in the supernatant solution by ICP. Measurements of the electrophoretic mobility in dispersions containing Ca(NO3)(2)(.)4H(2)O and KCl as background electrolyte were also performed both in the presence and in absence of NaHMP. The results allow a better understanding of the roles played by calcium ions and ageing of kaolin dispersions in the presence of NaHMP. They also shed light on the deflocculating mechanism of NaHMP. Correlations between theological parameters and chemical properties of the dispersions could be established.
2006
- Electrical behaviour of materials based on monoclinic celsian derived from cation-exchanged commercial zeolites
[Articolo su rivista]
A., Motori; F., Patuelli; A., Saccani; Andreola, Nora Maria; F., Bondioli; Siligardi, Cristina; Ferrari, Anna Maria
abstract
Abstract Monoclinic celsian has been obtained by a non-conventional way, i.e. the thermal treatment of 4A-type commercial zeolite: a stoichiometric amount of barium ions was included in the zeolite by means of a cation-exchange treatment. A small concentration of alkali ions (either sodium or lithium) was also present in the exchanged zeolite, since previous studies had underlined the positive effect of these ions on the formation of monoclinic celsian. This particular synthesis proves to be economic, due to the low-cost precursors, the low temperatures and the short times required. However, the presence of even a small content of alkali ions and a residual amorphous phase can negatively affect the insulating properties of the material, thus hindering its use in electrical insulating systems. The results so far obtained show that the material keeps good insulating properties at low temperature, but its conductivity and dielectric losses strongly increase above 200 °C. --------------------------------------------------------------------------------
2006
- MICROWAVE THERMAL INERTISATION OF ASBESTOS CONTAINING WASTE AND ITS RECYCLING IN TRADITIONAL CERAMICS
[Articolo su rivista]
Leonelli, Cristina; Veronesi, Paolo; Boccaccini, Dino Norberto; Rivasi, Maria Rosa; Barbieri, Luisa; Andreola, Nora Maria; Lancellotti, Isabella; Rabitti, Daniela; Pellacani, Gian Carlo
abstract
Asbestos was widely used as a building material prior to the 1970´s. It is well known that asbestos is a health hazard and its progressive elimination is a priority for pollution prevention. Asbestos can be transformed to non-hazardous silicate phases by microwave thermal treatment. The aim of this investigation is to describe the microwave inertization process of asbestos containing waste (ACW) and its recycling in porcelain stoneware tiles, porous single-fired wall tiles and ceramic bricks following industrial manufacture procedure. Inertised asbestos powder was added in the percentages of 1, 3, and 5 wt.% to commercially available compositions and then fired following industrial thermal cycles. Water absorption and linear shrinkage of the obtained industrial products do not present significant variations with additions up to 5 wt.% of microwave inertised ACW.
2006
- Non conventional synthesis of monoclinic celsian from Ba-exhanged zeolite A: study of the effect of residual Na and forming pressure
[Capitolo/Saggio]
C., Ferone; M., Pansini; Andreola, Nora Maria; Barbieri, Luisa; Siligardi, Cristina; Manfredini, Tiziano
abstract
Four samples of Ba-exchanged zeolite A, bearing 0.27, 0.43, 0.58 and 0.74 meq/g Na residual amounts, were thermally treated in the temperature range 200-1500 °C for times up to 28 hours. The same samples were pressed at 30 and 60 MPa to manufacture cylindrical pellets, which were thermally treated at 1300 °C for 5 hours. Thermally treated materials were characterized by room temperature XRD. The sequence of thermal transformations that Ba-exchanged zeolite A undergoes (zeolite ® amorphous phase ® hexacelsian ® monoclinic celsian) and the strong mineralizing action developed by Na are confirmed. Pressing the Ba-exchanged zeolite A powder-like samples to obtain cylindrical pellets is found to expedite the sluggish final phase transition hexacelsian ® monoclinic celsian. The optimum residual Na content of Ba-exchanged zeolite A to be transformed into monoclinic celsian is assessed to range between 0.27 and 0.43 meq/g.
2006
- Physical-chemical characterization of a galvanic sludge and its inertization by vitrification using container glass
[Relazione in Atti di Convegno]
Andreola, F.; Barbieri, L.; Cannio, M.; Lancellotti, I.; Siligardi, C.; Soragni, E.
abstract
Several industrial processes produce large amounts of heavy metals-rich wastes, which could be considered as "trash-can raw materials". The incorporation in ceramic systems can be regarded as a key process to permanently incorporate hazardous heavy metals in stable matrixes. In particular the aim of this work is to prepare and evaluate environmental risk assessment of coloured glass and glass-ceramic with the addition of chromium(III) galvanic sludge having a high content of Cr2O3 (15.91 wt%). Trivalent chromium compounds generally have low toxicity while hexavalent chromium is recognized by the International Agency for Research on Cancer and by the US Toxicology Program as a pulmonary carcinogen. The sludge has been characterized by ICP -AES chemical analysis, powder XRD diffraction, DTA, SEM, leaching test after different thermal treatments ranging from 400°C to 1200°C. Batch compositions were prepared by mixing this sludge with glass containers. The glass container composition is rich in SiO2 (69.89 wt%), Na 2O (12.32 wt%) and CaO (11.03 wt%), while the sludge has a high amount of CaO (42.90 wt%) and Cr2O3 (15.91 wt%). The vitrification was carried out at 1450°C in an electrical melting furnace for 2 h followed by quenching in water or on graphite mould. Chromium incorporation mechanisms, vitrification processability, effect of initial Cr oxidation state, and product performance were investigated. In particular toxic characterization by leaching procedure and chemical durability studies of the glasses and glass-ceramics were used to evaluate the leaching of heavy metals (in particular of Cr). The results indicate that all the glasses obtained were inert and the heavy metals were immobilized.
2006
- RF thermal plasma treatment of waste glass and its reutilization in composite materials
[Articolo su rivista]
V., Colombo; E., Ghedini; G., Masini; D., Russo; Andreola, Nora Maria; Barbieri, Luisa; Belviso, Daniela; Lancellotti, Isabella; Pozzi, Paolo
abstract
Fluorescent lamps glass powders are sieved in two particle size ranges and are subjected to thermal plasma in-flight treatment by injection into the discharge of a Tekna PL-35 plasma torch and reaction chamber as part of a source operated at 3MHz with a maximum power of 25kW, with Ar as plasma and carrier gas and N2 as sheath gas. The sieved powders and the plasma treated ones have been characterized by powder XRD and particle size analysis in order to verify if the plasma treatment can induce modification in the mineralogical and physical characteristics. The spherical shape of the particles have been analyzed by scanning electron microscopy. Moreover, this technique has allowed to verify if the plasma treatment can induce modification of the (qualitative) chemical composition of the powder. Results for various operating conditions and injection probe positions are presented. The spherical powders have been then introduced in thermoplastic polymer (polypropylene) in place of glass spheres usually used, and the results are compared to each others. The samples are characterized by mechanical tests (flexural strength) and microstructural analysis (SEM) in order to verify the differences in materials properties obtainable by mean of conventional and plasma assisted processes.
2006
- Role of the surface treatment in the deflocculation of kaolinite
[Articolo su rivista]
Andreola, Nora Maria; Romagnoli, Marcello; Castellini, Elena; Lusvardi, Gigliola; Menabue, Ledi
abstract
Suspensions of untreated and properly treated Na-exchanged kaolinite have been subjected to rheological investigations using sodium hexametaphosphate (NaHMP) or sodium disilicate (DIS) as deflocculants. The treatment of the clay consisted of a 24 h contact with solutions of NaHMP or DIS and separation of the resulting solid phase. This was then used to form the suspensions subjected to the rheological measurements. The results indicate that the dispersion ability of each deflocculants is remarkably influenced by the type of treatment. In particular, with respect to the untreated kaolinite, the efficiency of DIS is dramatically increased when the clay has been previously treated with a NaHMP solution. On the other hand, a decrease in the dispersant ability of NaHMP is observed from the untreated kaolinite to the one previously treated with DIS.
2005
- Applicazioni delle argille nell'industria ceramica
[Capitolo/Saggio]
Andreola, Nora Maria; Manfredini, Tiziano
abstract
I ceramici “tradizionali” sono prodotti ottenuti da materie prime largamente diffuse in natura quali argille, feldspati e sabbie quarzifere foggiati generalmente a freddo e sottoposti ad opportuni trattamenti termici in grado di innescare le trasformazioni fisiche (cambiamenti di fase, passaggio dallo stato cristallino a quello vetroso e viceversa,etc) e chimiche (reazioni di decomposizione, formazione di nuove fasi cristalline) che li rendono appropriati per il loro utilizzo (Ricciardiello& Palmonari, 1996).
Vengono usualmente indicati per applicazioni in edilizia (piastrelle, laterizi e sanitari), per uso domestico (stoviglieria, porcellana) e per uso industriale (porcellane tecniche e refrattari).
Nel saggio vengono descritte le composizioni degli impasti per piastrelle da pavimentazione e rivestimento che negli ultimi anni hanno subito un’evoluzione importante adattandosi fondamentalmente ai cicli di cottura rapida (inferiori a 60 min.).
2005
- Cathode ray tube glass recycling: an example of clean technology
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Corradi, Anna; Lancellotti, Isabella
abstract
In this study the use of 'cleaned' end of life (EOL) cathode ray tube (CRT) glass as a raw material in ceramic glazes is described. At present, the recycling and industrial utilization of CRT, a glass material from TV and computer sets, is a subject of intense research with particular regard to the so-called open-loop recycling, namely cycles different from that of the origin. However, the use of CRT glass as a secondary raw material is strictly related to the demand of high-quality raw material. The good preliminary results reached by introducing clean TV and PC monitor panel and cone glass into ceramic glaze formulations pushed research toward the setting-up of a base glaze that is exploitable for the production of pigmented, silk-screened and flame-hardened glazes (products used industrially for coating floor tiles). The aesthetic and chemical characterization of the tiles glazed by this product showed an extremely similar behaviour to originals that did not contain CRT glass. The good technical results achieved have been supported by the life cycle assessment analysis, which has demonstrated a reduction of the environmental impact of the CRT glass-containing ceramic glaze with respect to the standard one.
2005
- Glass-ceramics obtained by the recycling of end of life cathode ray tubes glasses
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Corradi, Anna; Lancellotti, Isabella; R., Falcone; S., Hreglich
abstract
This work is concerned with open-loop recycling of end of life Cathode Ray Tubes glass (an unsolved problem when considering that in Europe almost 90% of EOL electronic goods is disposed of in landfills), focusing on the development of glass-ceramics from panel or funnel glass with dolomite and alumina, and the evaluation of the tendency towards crystallisation with particular attention on composition and thermal treatment. Glasses were melted at a temperature of about 1500 degrees C and transformed into glass-ceramics by different thermal treatments (900 degrees C to similar to 1100 degrees C temperature range and 0.5 to similar to 8 h soaking time). By using the evaluation of thermal, mineralogical and microstructural data it has been pointed out that a good degree of crystallisation is reached at about 1000 degrees C and with a high proportion of waste glass (50-75%) if 40-45% of CaO and MgO bearer (dolomite) is introduced. In this way alkaline and alkaline-earth silicate and aluminosilicate mainly develop probably with a surface mechanism.
2005
- Influence of the pozzolanic fraction obtained from vitrified bottom-ashes from MSWI on the properties of cementitious composites
[Articolo su rivista]
A., Saccani; F., Sandrolini; Andreola, Nora Maria; Barbieri, Luisa; Corradi, Anna; Lancellotti, Isabella
abstract
Municipal Solid Waste Incineration Bottom Ashes (MSWI BA) have been submitted to a thermal treatment leading to their complete vitrification. The composition and the pozzolanic activity of the vitrified, grounded bottom ashes is evaluated, as far as the mechanical and microstructural properties of mortars containing up to 30 wt. % of this fraction (on cement weight), as a replacement of the hydraulic binder. At sufficiently long curing times, modified composites exhibit higher mechanical strengths and lower porosity than those of the unmodified ones. The same mortars show lower permeation to chlorides and sulphates and the tendency to depress the expansion generated by alkali-silica reactions (ASR). 1359-5997 © 2004 RILEM. All rights reserved.
2005
- Recycling industrial waste in brick manufacture. Part 1
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella; Pozzi, Paolo
abstract
The ongoing accumulation of industrial waste speaks to the need to seek cost-effective disposal methods. Brick manufacture would appear to be particularly promising in this regard. The present study analyzes the possibility of recycling the sludge generated in porcelain tile polishing, as well as coal, steel and municipal incinerator ash to make a special type of facing brick whose properties readily accommodate a full analysis of all the problems deriving from the incorporation of residue in its manufacture. Physical-chemical, mechanical and structural analyses were performed on bricks made with varying percentages of the different types of waste considered. This first paper reports the results of the physical and technological characterization of the products; the second part of the research will address their chemical, mechanical and structural properties.
2005
- Reutilization of waste inert glass from the disposal of polluted dredging spoils by the obtainment of ceramic products for tiles applications
[Articolo su rivista]
G., Brusatin; E., Bernardo; Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella; S., Hreglich
abstract
The vitrification treatment has been successfully exploited as a solution for the disposal of polluted dredging spoils from the industrial area close to the Venice Lagoon. The addition of 20% by wt. of glass cullet to the calcined sediments in the vitrification batch provides a suitable chemical composition for the production of an inert glass, despite the compositional variations of the sediments. The obtained waste glass, after being finely ground, has been employed (i) as a raw material for the manufacture of sintered glass-ceramics, by cold pressing and single-step sintering at about 940 degrees C, and (ii) as sintering additive (the maximum addition being 10% by wt.) for the manufacture of traditional red single firing ceramic tiles, with a maximum firing temperature of 1186 degrees C. Both applications have proved to be promising: in the first case, the sintered glass ceramic product exhibits notable mechanical properties (bending strength > 130 MPa, HV approximate to 6.5 GPa); in the second case, the addition of waste glass does not modify substantially the investigated physical and mechanical properties of the traditional product (water absorption, linear shrinkage, bending strength, planarity).
2005
- Sintered glass-ceramics and glass-ceramic matrix composites from CRT panel glass
[Articolo su rivista]
E., Bernardo; Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella
abstract
Sintering with simultaneous crystallization of powdered glass represents an interesting processing route for glass-ceramics, especially originating from wastes. Highly dense glass-ceramic samples may be obtained from a simple and short treatment at a relatively low temperature. In addition, glass-ceramic matrix composites may be obtained by mixing glass with suitable reinforcements. In this work sintered nepheline glass-ceramics, based on panel glass from cathode ray tubes, are illustrated. A limited addition of Al2O3 platelets caused a significant improvement in the mechanical properties (elastic modulus, bending strength, microhardness, fracture toughness), already remarkable for the un-reinforced glass-ceramic, compared with traditional nepheline glass-ceramics.
2005
- Sintered glass-ceramics from end of life cathode ray tubes glass
[Relazione in Atti di Convegno]
Andreola, F.; Barbieri, L.; Corradi, A.; Lancellotti, I.
abstract
The recycling of end of life cathode Ray Tubes from TV sets and PC monitors is still an unsolved problem. This study presents the feasibility results of the panel glass recycling glass from end of life TV sets as secondary raw material in glass-ceramic productions. The sintering and crystallization processes of the glass-ceramics resulting from the mixing of 50wt% glass with different percentages of dolomite and alumina was studied. The crystallization and densification processes were examined by DTA, XRD and SEM techniques and by linear shrinkage, density and water-absorption studies. The influences of heat treatment temperature was analysed. The best glass-ceramics consolidation and densification was obtained at 900°C for the lower rate alumina composition. The crystallisation begins near 900°C in grain surfaces and expands in the bulk with increasing temperature (1000°C). These glass-ceramics are composed of nepheline, akermanite and celsian, crystalline phases present also in commercial glass-ceramics such as Pyroceram and responsible of high mechanical strength.
2004
- New marketable products from inorganic residues
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Corradi, Anna; Lancellotti, Isabella
abstract
Ash from the incineration of municipal solid residues and from thermal power stations appear to be easily transformed to new marketable products, including glasses, glass ceramics and ceramics. Steel fly ash however presents many diificulties for insertion as a fundamental constituent into these products.
2004
- Smalti per piastrelle dal vetro di TV e monitor
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Corradi, Anna; M., Garzoni; E., Guidetti; Lancellotti, Isabella; A., Medici; Rabitti, Daniela; A., Sansone
abstract
-
2004
- The role of sodium hexametaphosphate in the dissolution process of kaolinite and kaolin
[Articolo su rivista]
Andreola, Nora Maria; Castellini, Elena; Manfredini, Tiziano; Romagnoli, Marcello
abstract
Suspensions of kaolinite and ceramic grade kaolin in sodium hexametaphosphate solutions at different concentrations were prepared and kept at constant temperature for 4 h: the solutions obtained after centrifugation and filtration were analysed using a ICP technique to determine the concentration of significant cations. The results allowed to stress the role of NaHMP in the dissolution process of kaolinite and ceramic grade kaolin. The role of accessory minerals in ceramic grade kaolin dissolution was discussed in the light of the obtained data.
2004
- “Polveri da trattamento fumi di industria siderurgica: esperienze di inertizzazione e di valorizzazione”
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Barbieri, L.; Lancellotti, Isabella; Poli, Giorgio
abstract
-
2003
- Comparison of various solvent media efficiency in the grinding of a frit containing zirconium oxide
[Articolo su rivista]
Andreola, Nora Maria; Mc, D'Arrigo; Leonelli, Cristina; Siligardi, Cristina; Pellacani, Gian Carlo
abstract
In the present work thermal and chemical properties of a glass-ceramic frit containing zirconium oxide are evaluated after milling in various polar and nonpolar solvents. Particle-size distribution is one of the main variables investigated to evaluate the efficiency of several solvents. Milling in various solvents does not affect the thermal properties of the glass while the presence of polar groups in the solvent molecule increases the cation release from the glass.
2003
- Delamination of italian kaolin: effect of reaction temperature and cristallinity on the urea rate intercalation
[Abstract in Atti di Convegno]
L., Garrido; Andreola, Nora Maria; Castellini, Elena
abstract
Urea is effective in kaolin delamination and cristallinity. The role of temperature in delamination has been investigated in different conditions.
2003
- Effect of ionic strength and temperature on the interaction between kaolin suspensions and sodium hexametaphosphate
[Abstract in Atti di Convegno]
Andreola, Nora Maria; Castellini, Elena; Manfredini, Tiziano; Romagnoli, Marcello
abstract
The effect of ionic strength on the interaction between kaolin and sodium hexametaphosphate has been investigated at different temperatures.
2003
- Inorganic wastes as new resource of materials
[Relazione in Atti di Convegno]
Barbieri, L.; Lancellotti, A.; Corradi, A.; Andreola, F.; Pozzi, P.
abstract
Recycling and valorisation of waste materials coming from municipal and industrial processes has become an urgent problem. Moreover, national regulations are reinforcing environmental protection measures, thus rendering the development of new recycling technologies necessary and convenient. By considering that both the ceramic industry is a high consumer of natural raw materials and these materials develop crystalline phases and glassy matrices capable to block the wastes it is easy to understand that the ceramic sector represents an important reference point for the recycling of wastes. The experimental work has been carried out by mixing incinerator bottom ash and steel ash in both a ceramic paste for red single firing and in a body for facing bricks. The samples characterisation has been conducted by means of linear shrinkage, water absorption, density, porosity, crystalline phases identification, plasticity, loss in weight and surface defects. From this feasibility study, can be evinced that both the processes allow the introduction of wastes in terms of chemical, physical, mineralogical and esthetical compatibility, in particular for percentage up to 5wt% because higher percentage causes major modifications in the standard bodies.
2003
- POSSIBILITÀ DI RICICLO DI VETRO DA CINESCOPI DISMESSI PER L’OTTENIMENTO DI VETRO-CERAMICI
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Corradi, Anna; Lancellotti, Isabella; R., Falcone; S., Hreglich
abstract
-
2002
- Chemical additives for pressure tape casting
[Articolo su rivista]
Andreola, Nora Maria; Castellini, Elena; Romagnoli, Marcello
abstract
Suspensions of ceramic raw material and different deflocculant polyelectrolytes were prepared with a solid content of about 78% in industrial water. The rheological behavior of these suspensions was tested by evaluation of the shear dependence in a 4-step cycle and by a modified off-on procedure that reproduced the typical times involved in tape casting. The best deflocculants were found to be Na hexametaphosphate and polyacrylate, but their capability differed a little from mixtures of hexametaphosphate and Na disilicate or from ternary mixtures. The deflocculants made the suspensions slightly dilatant, had a low viscosity and yield stress values close to zero, that permitted an easy degasification of the suspensions. The additives, alone or in mixture, had adequate characteristics for use in pressure tape casting.
2002
- Recycling of the waste waters into porcelainized stoneware ceramic tiles: effect on the rheological, thermal and aesthetical properties
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella; Manfredini, Tiziano
abstract
The importance of the porcelainized stoneware production, this product reached the 36% (218.106 m2) of the total Italian production in the last year, and the impossibility to reuse both the ceramic residues and the process waste waters with the similar practice developed previously for the other typologies have brought to find new solutions to applied at this kind of wastes. The aim of the work is to evaluate the possibility to recycle waste waters, deriving from different technological ceramic cycles, inside the porcelainized stoneware body. The use of these waters does not change the parameters of the productive cycle, obtaining a final product with the similar quality and aesthetic characteristics required from the market and avoiding a possible spilling of the waste water after purification in sewers or in superficial river courses.
2002
- Rotational Rheometry used as Laboratory Technique to Test Commercial Deflocculants
[Articolo su rivista]
Andreola, Nora Maria; Romagnoli, Marcello
abstract
This study considers the use of rotational rheometry as a laboratory technique to control the efficiency of different commercial deflocculants on kaolin suspensions. In particular, three commercial Penta Sodium Tripolyphosphates (STPP), which are widely used in the ceramics industry, were tested. In order to characterise the Tripolyphosphate (TPP) salts, chemical and physical analyses were carried out. The aim of this study is to highlight the ability of rheometric techniques to describe the effects of the different additives with fast and easy procedures that can be utilised on industrial or laboratory scale. The rheological measures were performed on kaolin suspensions with different amounts of TPPs salts addition. As a liquid medium, industrial water with calcium and magnesium ions was simulated.
2002
- Tape casting sotto pressione di sospensioni acquose di allumina
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Manfredini, Tiziano; Romagnoli, Marcello
abstract
Tape casting sotto pressione di sospensioni acquose di allumina
2002
- The influence of the Mean Free Path between Particles on the apparent Viscosity of Clay Slips
[Articolo su rivista]
J. B., RODRIGUES NETO; A. P., NOVAES DE OLIVEIRA; O. E., Alarcon; Pozzi, Paolo; Andreola, Nora Maria
abstract
Studies of the rheological behaviour of clay suspension
2002
- Urban incinerator grate ash used as raw material to produce sintered glass-ceramics
[Articolo su rivista]
Barbieri, Luisa; Andreola, Nora Maria; Corradi, Anna; Lancellotti, Isabella
abstract
Sintering is shown to be a very convenient alternative way to valorise urban incinerator grate ash as raw material to produce glass-ceramics. The results reached by thermal, mineralogical, physical and microstructural analysis show that it is possible to obtain sintered finished products constituted of common silicate crystalline phases (wollastonite, diopside/augite) by heat treatments with shorter time and lower temperature with respect to the bulk devitrification.
2002
- Utilisation of municipal incinerator grate slag for manufacturing porcelainized stoneware tiles manufacturing
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Corradi, Anna; Lancellotti, Isabella; Manfredini, Tiziano
abstract
Porcelainized stoneware tiles containing up to 20 wt.% of municipal incinerator grate slag have been fabricated by cold uniaxial pressing and conventional fast firing cycles. The sinterability of these samples was investigated from density and shrinkage measurements together with mechanical (Vickers microhardness and Young's modulus) and esthetical (spot resistance and colour parameters analysis) properties. The comparison with the porcelainized stoneware tiles containing no waste suggest a good compatibility between the ceramic body and the waste that does not significantly change the properties of the final products and the conditions of the firing cycle. Nevertheless, the porosity increase, proportional to the waste content, causes a decrease in density, shrinkage, spot resistance and whiteness. (C) 2002 Elsevier Science Ltd. All rights reserved.
2002
- Valorizzazione di rifiuti inorganici nel settore ceramico
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Barbieri, Luisa; Corradi, Anna; Lancellotti, Isabella; Romagnoli, Marcello
abstract
Valorizzazione di rifiuti inorganici nel settore ceramico
2002
- Zeta potential and rheological behaviour of aqueous kaolin suspensions dispersed with sodium hexametaphosphate
[Capitolo/Saggio]
Andreola, F.; Castellini, E.; Romagnoli, M.; Olhero, S. M.; Ferreria, J. M. F.
abstract
Deflocculants adsorb on particles' surfaces, increase the repulsive forces among them, reducing viscosity, while the soluble salts have an opposite effect on viscosity. This work studies the influence of deflocculant and salt concentration on zeta potential and correlates the results with rheological measurements.
2001
- Binary and ternary mixtures of deflocculant additives for whiteware slurries
[Relazione in Atti di Convegno]
Andreola, F.; Pellacani, G. C.; Romagnoli, M.
abstract
In the traditional ceramic field, during the wet grinding stage liquid mixtures of additives are commonly used to guarantee high solids content (65-72 wt%) and a viscosity low enough to allow the suspension's workability. These characteristics are indispensable for using the new technologies for wet grinding (cylindrical and conical continuous mills) that require only 3-4 h of milling and permit considerable productivity (20 t/h). This work reports a laboratory study on the rheological behavior of whiteware slurries added with binary and ternary deflocculant mixtures.
2001
- Binary and ternary mixtures of deflocculating additives for whitewares slurries.
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Romagnoli, Marcello; Pellacani, Gian Carlo
abstract
In the traditional ceramic field, during the wet grinding stage liquid mixtures of additives are commonly used to guarantee high so/ids content (65–72 wt%) and a viscosity low enough to allow the suspension's workability. These characteristics are indispensable for using the new technologies for wet grinding (cylindrical and conical continuous mills) that require only 3–4 h of milling and permit considerable productivity (20 t/h). This work reports a laboratory study on the rheological behavior of whiteware slurries added with binary and ternary deflocculant mixtures.
2001
- Comportamento Reologico di smalti ceramici: influenza della composizione e delle variabili di preparazione delle fritte
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Romagnoli, Marcello
abstract
Comportamento Reologico di smalti ceramici: influenza della composizione e delle variabili di preparazione delle fritte
2001
- Environmentally conscious sintered glass-ceramics
[Relazione in Atti di Convegno]
Barbieri, L.; Corradi, A.; Lancellotti, I.; Andreola, F.; Boccaccini, A. R.
abstract
Sintered glass-ceramics have been produced using municipal incinerator solid residues and glass culler or an inert waste, from feldspars processing, as sintering aids. The capability of three different mixtures, either previously vitrified or not, to be sintered was investigated by means of linear shrinkage, water absorption and bulk density measurements, and by X-ray diffraction analysis and scanning electron microscopy observations. Particular attention has been addressed to the study of particle size effect on the sintering process. The conclusions that can be drawn from the experimental study are that the preliminary vitrification step is essential in order to obtain a dense sintered glass-ceramic product in the 850-1050°C temperature range developing silicate crystalline phases. The optimal powder particle size that confers a good densification degree was found to be < 45 μm.
2001
- La fluidità delle polveri ceramiche: metodi di misura e variabili che influenzano lo scorrimento
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Romagnoli, Marcello
abstract
ISBN-88-8138-097-8
2001
- Problematiche e prospettive di recupero ed utilizzo dei fanghi di levigatura del gres porcellanato
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa
abstract
-
2001
- Problematiche e prospettive di valorizzazione di scorie di inceneritore urbano nel settore ceramico
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella
abstract
-
2001
- Recycling in the Italian ceramic tile factories
[Capitolo/Saggio]
Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella; Manfredini, Tiziano
abstract
In the Italian reality the unfired and fired by-products are totally recycled in the manufacturing cycle, and only those residues coming from depuration processes (glaze sludges and exhausted lime) cause technological problems, being less useful for recycling. Statistical data of the produced quantities, treated and recycled, divided by categories, are shown. Furthermore, we analyze a new category of ceramic residue, polishing sludges, that owing to their chemical characteristics, are not recycled in the ceramic bodies. We propose to reuse them as secondary raw materials to obtain porous materials with insulating properties by controlled thermal treatments.
2001
- The possibility to recycle solid residues of the municipal waste incineration into a ceramic tile body
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Corradi, Anna; Lancellotti, Isabella; Manfredini, Tiziano
abstract
The feasibility of utilising solid residues of the municipal wastes incineration such as grate (bottom) ash and electrofilter and sleeve filter fly ash, in combination with a porcelain stoneware body, in the preparation of tiles has been investigated. While the chemical, mineralogical, thermal and rheological characterisation of the waste raw materials carries out some problems arising by using fly ash, these seem to be overcome with the bottom ash. The introduction of up to 20 wt% of this powder into the ceramic body does not substantially change the mineralogical and thermal behaviour of the product.
2001
- Valorization of a steel plant fly ash in a CMAS glass-ceramic
[Capitolo/Saggio]
Barbieri, Luisa; Andreola, Nora Maria; Corradi, Anna; Lancellotti, Isabella
abstract
Stable and inert glasses in the SiO2-Al2O3-CaO-MgO glass-ceramic system were prepared by adding up to 10 wt% of a steel plant fly ash, and subsequently crystallized. Steel waste dust acts mainly on the optical and thermal properties, without modifying the devitrification mechanism. In particular, the role of structure modifiers Fe2O3 and ZnO, the main oxides present in the waste, is to lower the viscosity and refractoriness of the system. Iron, present mainly in tetrahedral coordination in a 3+ oxidation state, confers yellow-brown color to the glasses. As a consequence of heat treatment, pyroxenic glass-ceramics develop with a surface mechanism, as in the CMAS parent system. On the basis of a previous work, the effect of steel waste dust is reasonably comparable to that of pure iron oxide, with the advantage of using an inexpensive raw material with a good environmental impact factor.
2000
- Effetto di Additivi Chimici sulle Caratteristiche Reologiche di Sospensioni Ceramiche Tradizionali per Tape-Casting.
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Castellini, E.; Romagnoli, Marcello
abstract
Sono presentati i risultati di una sperimentazione che ha visto l'utilizzo di tre diverse tipologie di additivi su un impasto di tipo industriale e avente come intento l'individuazione di additivi che permettano, a parità di contenuto solido, di ridurre la viscosità della sospensione, attraverso una razionale serie di prove. Viene mostrato quali additivi o miscele permettono di ottenere i comportamenti reologici piu adeguati a tale tecnica di formatura. Parametri reologici quali la viscosità e la tissotropia delle sospensioni sono messi in relazionealla composizione degli additivi.
2000
- Glass-ceramics sintered by glassy powders of no hazardous special wastes
[Articolo su rivista]
Barbieri, Luisa; Corradi, Anna; Lancellotti, Isabella; Manfredini, Tiziano; Andreola, Nora Maria
abstract
An alternative method for recycling municipal incinerator grate ash is proposed. The glassy powder is sintered to obtain glass-ceramic materials. The results obtained from mineralogical, physical and microstructural analyses show that it is possible to obtain dense finished products consisting of common silicate crystalline phases (wollastonite, diopside) by firing treatments with shorter time and lower temperature with respect to bulk devitrification. 20 refs.
2000
- Microwave technology applied to the recycling of fine stoneware tiles polishing sludge compared to conventional firing
[Articolo su rivista]
Andreola, Nora Maria; Leonelli, Cristina; Siligardi, Cristina; C., Leonelli; Corradi, Anna
abstract
Microwave technology was a useful heating process when applied to the recycling of fine stoneware tiles polishing sludge. The manufact processed were characterized by low porosity, much lower than that registered for the same formulation heated with conventional firing.The different microstructure has been explained by considering the selective heating phenomenon generated by microwave irradiation: the SiC particles could heat much faster that the aluminosilicate matrix so that to melt the surroundings with a sort of encapsulation process.Conventional heating lead to SiC reaction with oxygen promoting its conversion in CO2 thus creating large pores.
2000
- Optimization of fritting parameters of ceramic frits: effect on the rheological behavior of the glaze suspensions.
[Articolo su rivista]
Andreola, Nora Maria; Castellini, E.; Romagnoli, Marcello
abstract
Studies to optimize the prepn. parameters used in industrial frits are reported. Two frit compns. widely used for the prodn. of single-fired ceramic-glazes were chosen: an alk. boric and an earth-alk. boric compn. The chem. durability and rheol. behavior of the frit suspensions were studied in relation to changes in the fritting temp. and time. The results confirm that the two frits studied react differently to changes in fritting parameters due to the dependence on their chem. durability and compn. Suspensions prepd. with the alk.-boric frit displayed no significant change in their rheol. properties; the earth-alk.-boric frit suspensions were more markedly affected.
2000
- Optimization of fritting parameters of ceramic frits: effect on the rheological behaviour of the glaze suspensions
[Articolo su rivista]
Andreola, Nora Maria; Castellini, Elena; Romagnoli, Marcello
abstract
Studies to optimize the preparation parameters used in industrial frits are reported. Two frit compositions widely used for the production of single-fired ceramic-glazes were chosen: an alkaline boric and an earth-alkaline boric composition. The chemical durability and rheological behavior of the frit suspensions were studied in relation to changes in the fritting temperature and time. The results confirm that the two frits studied react differently to changes in fritting parameters due to the dependence on their chemical durability and composition. Suspensions prepared with the alkaline-boric frit displayed no significant change in their rheological properties; the earth-alkaline-boric frit suspensions were more markedly affected.
2000
- Techniques used to determine porosity
[Articolo su rivista]
Andreola, Nora Maria; Leonelli, Cristina; Romagnoli, Marcello; Miselli, Paola
abstract
A comparison is made of the principal techniques (mercury porosimetry, helium pycnometry, image analysis and water absorption) that are used to measure porosity
2000
- Tecniche a confronto per la determinazione della porosità. Parte II
[Articolo su rivista]
Andreola, Nora Maria; Leonelli, Cristina; Romagnoli, Marcello; P., Miselli
abstract
Viene presentata I'applicazione delle tecniche presentate nella parte I a sei prodotti ceramici con diverse proprietà. Ogni tecnica utilizzata infatti risulta idonea per determinate classi di materiali; pertanto la scelta del procedimento di analisi viene fatta a seconda del tipo di risultato che si vuole ottenere. Lo scopo di tale lavoro e quello di evidenziare i vantaggi e gli svantaggi di ognuna a seconda del materiale sottoposto ad analisi.
2000
- The influence of additives on the rheological behavior of acqueous concentrated glaze suspensions.
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Romagnoli, Marcello; Pellacani, Gian Carlo
abstract
Influenza di alcuni additivi chimici sul comportamento reologico di sospensioni di fritte ceramiche.
1999
- Dry glazing in ceramic tile production.
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Romagnoli, Marcello
abstract
The efficiency of four different methods used to measure the flowability of the powders has been studied. The results obtained on pigments used in the production of tiles were correlated with the data obtained in semi-industrial conditions.The influence of the powder moisture on the amount of pigment that falls on the tile's surface was evaluated.
1999
- Influence of the operative parameters on chemical durability and rheological behavior frits ceramic suspensions.
[Relazione in Atti di Convegno]
Andreola, Nora Maria; D., Bernardelli; Romagnoli, Marcello; Pozzi, Paolo
abstract
Glaze application is the phase in a productive process that is more conditioned from the rheological properties of the glaze itself. During the preparation step in the mill, at moderately high temperatures (60-70°C), reactions between frits and the aqueous medium can occur and consequently begin the leaching of glassy network and the diffusion of the modifying ions through the leached frit layer. In the industrial process, variations on the pH and the ionic strength of glaze suspensions happen during the milling. Consequently changes on the rheological parameters (apparent viscosity, yield point, thixotropy) of glaze suspensions will verified. It is important to control these variables for keeping unaffected the aesthetic characteristics of the final products, after firing.
1999
- Reologìa de suspensiones de esmaltes cerámicos para monococción: estudio de la influencia de los aditivos utilizados.
[Articolo su rivista]
Andreola, Nora Maria; Pozzi, Paolo; Romagnoli, Marcello
abstract
En este trabajo se presentan los resultados obtenidos a partir de la caracterización y el estudio del comportamiento reológico de suspensiones de fritas cerámicas para la elaboración de esmaltes para baldosas de monococión porosa.En particular se evidencian los efectos que los distintos componentes y aditivo, ejercen sobre los parámetros reológicos que oontrolan las fases de preparacion y de aplicación
1999
- Rheology of ceramics slurries with mixtures of deflocculanting agents.
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Castellini, Elena; Romagnoli, Marcello
abstract
In whiteware processing, as in most other technical processes involving concentrated suspensions, additives are used to decrease viscosity and control stability. Silicate, phosphate and polyacrylate sodium salts are the most used additives in the production of tiles, tablewares, sanitarywares etc. They are commercially available products with good deflocculant abilities and performance/costs ratio. The chemical action of each single component was studied1,2,3 but the authors are not aware of any studies on mixtures. The systems are complex because they are multi-phases and constituted by natural raw material. In the industrial field, liquid mixture of additives are generally used. They take an inferior amount of time before being active with respect to when they are used as solid salts and permit a better management in the plant.
1998
- Caratterizzazione di sospensioni acquose di fritte ceramiche additivate di materiali plastici
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Pozzi, Paolo; Romagnoli, Marcello
abstract
Caratterizzazione di sospensioni acquose di fritte ceramiche additivate di materiali plastici
1998
- Comparison Between poly(vynil acetate) and poly(vynil alcohol) as Binders for whiteware body composition.
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Romagnoli, Marcello; W., Carty
abstract
Comparison Between poly(vynil acetate) and poly(vynil alcohol) as Binders for whiteware body composition to avoid spring-back phenomena during forming.
1998
- Rheological behavior of an STP deflocculated kaolin
[Articolo su rivista]
Andreola, Nora Maria; Pozzi, Paolo; Neto, Jbr
abstract
Work attempts to characterize a physical chemical parameter responsible for fluctuations in the efficiency of STP's deflocculant ability in industrial use.
1998
- Rheological behavior of kaolin acqueous suspensions deflocculated with sodium tripolyphosphate at different ratio of crystalline phase
[Articolo su rivista]
Andreola, Nora Maria; J. B., Nieto; Pozzi, Paolo
abstract
Rheological behavior of kaolin suspensions deflocculated with sodium tripolyphosphate at different ratio of crystalline phase
1998
- Utilizzo di scorie da inceneritore urbano nella produzione di gres porcellanato
[Articolo su rivista]
Andreola, Nora Maria; Barbieri, Luisa; Lancellotti, Isabella; F., Mavridis; Pozzi, Paolo
abstract
-
1997
- Impiego di carbossimetilcellulose come leganti negli smalti ceramici : studio del comportamento reologico
[Relazione in Atti di Convegno]
Andreola, Nora Maria; R., Lapasin; Pozzi, Paolo; Romagnoli, Marcello
abstract
Studio reologico dell'aggiunta di CMC in sospensioni di smalti ceramici per piastrelle.
1997
- Sintering and modification of porous structure caused by binders added to whiteware body composition
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Romagnoli, Marcello; Pozzi, Paolo
abstract
The behavior of 2 viscosity-grade polyvinyl alcohols. was studied at 2 different percentages added to the slurry used for the preparation of tableware by isostatic pressing. The modification of the porous structure, the apparent d., and the elimination of the binder were examined. Results obtained show that binders do not modify the reactions during the firing process. More evident differences are verifiable in the porosity of the green and fired bodies, according to their mol. wt. and concn. Porosity decreased until 350°C (200°C for the binder with high mol. wt.), while from 450°C (350°C high wt. binder) to 700°C it increased quickly. At higher temps., as an effect of sintering, porosity fell dramatically to <3% and residual porosity is concd. in large pores. Effect of mol. wt. is to det. a higher porosity using the binder with longer chain while the bulk d. is lower. The green body with higher percentage of adhesive presents a lower open porosity and bulk d.
1997
- Wet grinding ceramic frits: effects of the size of the grinding media, grinding time and solid content.
[Articolo su rivista]
Andreola, Nora Maria; Pozzi, P.; Romagnoli, Marcello
abstract
The effect of variables in the wet grinding process, such as the size of the grinding media, grinding time and solid content, was investigated using an aq. suspension of glassy frit, typically used for the prodn. of glazes in the manuf. of ceramic tiles. The aim was to examine the process parameters which will enable optimization of the grinding process for brittle materials. The frit was ground with three mill charges, formed of sintered alumina balls of different sizes, and the particle size dimensions were measured as a function of grinding time and of the amt. of solid content of the aq. suspensions. The results indicate that the mill charge ( ratio of grinding ball diams.), grinding times and solid content of the suspensions must be carefully controlled in order to optimize the grinding process. A lower limit of particle size dimensions, after very long grinding times, was obtained.
1997
- Zeolititi nazionali nella depurazione di acque reflue e loro successivo utilizzo in impasti ceramici
[Articolo su rivista]
Andreola, Nora Maria; Manfredini, Tiziano; Passaglia, Elio; Pellacani, Gian Carlo
abstract
Vengono riportati i risultati di uno studio eseguito con lo scopo di valutare la capacità di una zeolite italiana nella depurazione di una soluzione contenente Pb, Ba e Zn ed il suo successivo utilizzo all'interno di imapsti ceramici per la produzione di piastrelle da pavimentazione.
1996
- Additives used in the pressing of tableware
[Articolo su rivista]
Andreola, Fernanda; Pozzi, Paolo; Romagnoli, Marcello; Bresciani, Andrea; Pasquali, Guelfo
abstract
Reported here is the study of the rheological behavior of three viscosity-grade poly(vinyl alcohol)s added at three concentrations to a slurry that is used for the preparation of tableware by isostatic pressing. The formation of fracture during pressing, mechanical characteristics of the body and recycling of scrap also are reported.
1996
- Additives used in the pressing of tableware
[Articolo su rivista]
Andreola, Nora Maria; Pozzi, Paolo; Romagnoli, Marcello; Bresciani, A; Pasquali, G.
abstract
Binder monomer chain length and concentration affect the mechanical behavior of tableware during fabrication by isostatic pressing.
1996
- CONFRONTO TRA IL COMPORTAMENTO LEGANTE Dl ALCOOLPOLIVINILICI A DIVERSO PESO MOLECOLARE E ACETATO Dl POLIVINILE IN COMPOSIZIONI PER PIATTI A IMPASTO BIANCOOTTENUTI PER PRESSATURA ISOSTATICA
[Articolo su rivista]
Andreola, Nora Maria; Pozzi, Paolo; Romagnoli, Marcello; G., Pasquali; A., Bresciani
abstract
La pressatura isostatica, negli ultimi anni, e stata applicata con successo nella fabbricazione di refrattari e stoviglieria, può essere utilizzata nella fabbricazione di quasi tutte le forme di piatti e anche di articoli più complessi non simmetrici; tale procedimento tuttavia presenta il fenomeno della rapidaespansione del pezzo dopo la pressatura, con conseguente danneggiamento del manufatto. Al fine di evitare l'inconveniente si aggiungono all'impasto leganti in grado di opporsi all'espansione. Il lavoro qui riportato riferisce sui risultati ottenutidall'impiego di tre alcool polivinilici, aggiunti in tre diverse percentuali in barbottine utilizzate per la preparazione di piatti con la pressatura isostatica.
1996
- Comparison of the binding behavior of poly(vinyl alcohol) with varying molecular weight and poly(vinyl acetate) in compositions for white body plates obtained by isostatic pressing.
[Articolo su rivista]
Andreola, Nora Maria; Pozzi, P.; Romagnoli, Marcello; Pasquali, G.; Bresciani, A.
abstract
Over the past few years, the isostatic pressing method has been successfully applied for the prodn. of refractories and tableware. This method may be used for the prodn. of practically all shapes of plates, and also for more complex non-sym. pieces. This procedure leads to a rapid expansion of the piece after pressing, possibly resulting in damage. To avoid this problem, binding agents are added to the bodies which are capable of combating the expansion phenomenon. The effects of three types of poly(vinyl alc.) (varying mol. wt.), added in three different quantities, and poly(vinyl acetate) on this expansion phenomenon in the isostatic pressing of plates were examd.
1996
- Studio della tempo dipendenza in presenza di effetti irreversibili in sospensioni di fritte ceramiche
[Relazione in Atti di Convegno]
Andreola, Nora Maria; R., Lapasin; Pozzi, Paolo; Romagnoli, Marcello
abstract
Studio della tempo dipendenza in presenza di effetti irreversibili in sospensioni di fritte ceramiche
1995
- La depuracion y el reciclaje de residuos en la industria ceramica de baldosas
[Articolo su rivista]
Andreola, Nora Maria; Manfredini, T.; Pellacani, G. C.; Pozzi, Paolo
abstract
Studio dell'utilizzo di residui della depurazione di acque industriali in materiali ceramici
1995
- Microestructura y propriedades de baldosas de ares porcelanico obtenidas por monococcion rapida de una tipica pasta ceramica caolinitica
[Articolo su rivista]
Andreola, Nora Maria; Manfredini, T.; Pellacani, G. C.; Romagnoli, Marcello
abstract
Este estudio tiene como objetivo profundizar el conocimiento de la evoluciòn de la microestructura y correlarlas a las materias primas utilizadas; investigar las reacciones quìmicas entre los componentes presentes en las formulaciones de las pastas usadas para la producciòn de grès porcelànico y en particular los efectos de los materiales caolìniticos en el desarrollo de la microestructura del producto durante la cocciòn.
1995
- Recycling of Ceramic wastes to reduce pollution
[Articolo su rivista]
Andreola, Nora Maria; Manfredini, Tiziano; Pellacani, Gian Carlo; Pozzi, Paolo; Romagnoli, Marcello
abstract
Exhausted limes and sludges (containing prevalently glass frits and glaze components), are waste substances to be eliminated. Recycling of about 0.10-0.15 wt% of exhausted lime and about 0.50 wt% of glass frits permits their complete elimination without affecting the industrial process. Release tests demonstrate as the firing process acts in the inertization of soluble heavy-metals ions.
1995
- Reologia di sospensioni acquose di argille deflocculate con TPF a differenti fasi cristalline
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Pozzi, Paolo; Romagnoli, Marcello
abstract
Reologia di sospensioni acquose di argilla deflocculate con tripolifosfato di sodio a differenti fasi cristalline.
1994
- CONCENTRATED GLAZE SUSPENSIONS
[Articolo su rivista]
Andreola, Nora Maria; Corradi, Anna; Manfredini, Tiziano; Pellacani, Gian Carlo; Pozzi, Paolo
abstract
The effect of grinding time, solid slip content, kaolin plasticizer and Ca2+ flocculating agent on the rheological behavior of a typical industrial frit used in glazes for monoporosa wall tile are described.
1994
- Rheological behaviour of aqueous concentrated suspensions of an Italian zeolite
[Articolo su rivista]
Andreola, Nora Maria; Manfredini, T.; Pellacani, G. C.; Pozzi, Paolo; Romagnoli, Marcello
abstract
The paper reports a laboratory study on the rheological behaviour of concentrated aqueous suspensions of zeolitite, belonging to the geological formations of «tufo giallo napoletano» in the Phlegraean Fields (Campania). Rheological measurement performed by means of a rotational viscometer demonstrated how the suspensions show a practically newtonian behaviour up to about 40 wtOfo of solid content in absence of deflocculants and up to about SO wtOfo of solid content in presence of Na-SIL and Na-TPP detlocculants. At higher solid concentrations they assume a non-newtonian behaviour. Na-TPP shows a greater deflocculating ability toward zeolite suspensions than Na-SIL. This may be explained by considering, in particular, its sequestering action towards the flocculating ions.
1994
- Utilization of an Italian zeolitite in ceramic bodies
[Articolo su rivista]
Andreola, Nora Maria; Manfredini, Tiziano; Passaglia, Elio; Pellacani, Gian Carlo; Pozzi, Paolo; Romagnoli, Marcello
abstract
UTILIZATION OF ITALIAN ZEOLITITE IN CERAMIC BODIESThe papers reports a laboratory and industrial study on the possibility of using an Italian natural zeolitite, both in natural and Pb-; Ba- exchanged form, in a tile ceramic body. Because of their exchangeable cation contents (Na+, K+; Ca+2, Ba+2, Pb+2), natural and exchanged zeolitites can be added (up to 20 and 5wt%, respectively) in a ceramic body, thus favouring its sinterability and unaffecting the crystalline phase formation and the final products characteristics. The addition of higher amounts enhaces the swelling of the tiles during firing and strongly modifies the features of the fired tiles. Release tests in acetic and nitric acid solutions on unfired and fired tiles containing exchanged zeolitites demostrated the inertization of lecheable Pb+2 during firing.
1993
- Addition of exhausted lime in ceramic bodies: possibilities for an environmentally compatible tile production
[Articolo su rivista]
Andreola, Nora Maria; L., Bonfatti; Manfredini, Tiziano; Pellacani, Gian Carlo; Pozzi, Paolo; Romagnoli, Marcello
abstract
Pollution caused by inorganic wastes in the traditional ceramics industry is minimised by utilising exhausted limes, which are the byproducts in bag filters after the purification of flue gases in wet tile production. This study determined which quantities of exhausted lime added to tile bodies did not significantly affect the physico-chemical properties of the slips (i.e. density /viscosity/deflocculant amount) during wet grinding in ball mills. The results demonstrated that these conditions are obtained when exhausted lime in the bodies does not exceed 0.10 to 0.12 mass%. Furthermore, any increase in fluorine emission in the firing of tiles with exhausted lime can be trapped in the bag filters by increasing the lime content by about 10 mass%. The laboratory and industrial results are also compared.
1993
- Addition of exhausted lime in ceramic bodies: possibilities for an environmentally compatible tile production III: Industrial Results
[Articolo su rivista]
Andreola, Nora Maria; Bonfatti, L.; Manfredini, T.; Pellacani, G. C.; Pozzi, Paolo; Romagnoli, Marcello
abstract
study uses exhausted lime in ceramic
1993
- Recycling of ceramic wastes in tile bodies to reduce pollution
[Articolo su rivista]
Andreola, Nora Maria; Manfredini, Tiziano; Pellacani, Gian Carlo; Pozzi, Paolo; Romagnoli, Marcello
abstract
During recent years, special attention has been devoted both to solving pollution problems during the manufacturing of ceramics and to learning how ceramics can themselves be a solution. Waste encapsulation opportunities for structural clay products have been studied. These opportunities affect environmental isolation within the semivitreous matrix of the product and remove and destroy volatile organic components of the waste and recrystallized incinerator slags and encapsulant for such heavy metals as lead. To reduce hazards to workers and community and to realize a safe environment, some manufacturers have planned for a production process that recycles wastes. This plan represents the best option to reduce or minimize pollution by permitting the complete elimination of wastes and thus avoiding their very expensive storage in appropriate dumps. Studies have been performed to evaluate the effects of the presence of exhausted lime and sludges in tile bodies and to obtain information for the rationalization of the recycling process. The focus has been on the evaluation of the effects of the presence of wastes on the rheological and thermal behavior of the tile bodies. In addition, the efficiency of the firing process on the wastes and heavy-metals inertization has been determined by release tests of the fired products in different acidic media.
1993
- Reuse of waste lime in a ceramic body that generated it.
[Articolo su rivista]
Andreola, Nora Maria; Manfredini, T.; Romagnoli, Marcello
abstract
Results are presented from studies of the effect of addns. of waste lime on the rheol. behavior of tile-body slips, the dilatometric behavior of tile bodies, water absorption and shrinkage of fired tiles, and the tile microstructure development during firing. A <0.1 wt.% addn. of waste lime had negligible effect on the apparent viscosity of slips, and an .apprx.0.5 wt.% addn. did not product significant changes in the microstructure. Control of F emissions due to recycling of the CaF2-contg. waste lime is discussed.
1992
- Addition of exhausted lime in ceramic bodies:possibilities for an environmentally compatible tile production II:thermal behaviour of bodies
[Articolo su rivista]
Andreola, Nora Maria; Bonfatti, L.; Manfredini, T.; Pellacani, G. C.; Pozzi, Paolo
abstract
study uses exhausted lime in ceramic
1992
- Reactivity of CaF2 Toward Components of Ceramic Bodies.
[Relazione in Atti di Convegno]
Andreola, Nora Maria; Manfredini, Tiziano; Pellacani, Gian Carlo; Romagnoli, Marcello
abstract
The production of ceramic tiles results in the expulsion of many wastes. One of the waste substances which could be eliminated from the tile-making process is the exhausted lime which contains calcium fluoride as the main component. The maximum amount of exhausted lime which can be recycled without modifying the properties of the tiles is determined. The effects of the calcium fluoride on the microstructure of the tiles is investigated. It is discovered that addition of CaF2 greater than 0.5-1.0 wt% results in a strongly modified microstructure. Anorthite is produced at the expense of mullite leading to swelling of the tiles at the industrial firing temperatures.
1992
- addition of exhausted lime in ceramic bodies: possibilities for an environmentally compatible tile production I: rheological of slips
[Articolo su rivista]
Andreola, Nora Maria; Bonfatti, L.; Manfredini, T.; Pellacani, G. C.; Pozzi, Paolo
abstract
study of the rheology of ceramic suspension with recicling material presence