Reuse of glass waste in the manufacture of ceramic tableware glazes

Today, various studies are carried out to spread the understanding of sustainability. The sustainability of production processes gains importance in corporate areas. In this study, the use of glass waste instead of frit used in glaze compositions in the ceramic industry was evaluated. The chemical and physical properties of glass wastes on samples were examined. The glaze formulations were prepared using 3%, 5%, and 8% by weight of glass waste instead of frit. Glass wastes were added to glaze compositions and 12 different glaze formulation studies were carried out. Transparent, Opaque, and Matte test glazes were prepared with glass waste added glaze formulations, and these glazes were applied to ceramic bodies. SEM (scanning electron microscope) analysis of standard glaze and glass waste added glazes was performed to determine the microstructural and morphological characterizations. Also, surface whiteness, brightness, L*a*b values, glaze flows, harcort test results, and final water absorption values were compared. As a result of the studies, it has been determined that it is appropriate to use 3% glass waste by weight instead of the frit in the production of ceramic tableware.     

Usage of marble wastes in traditional artistic stoneware clay body

Recycling of industrial wastes aids environmentally friendly production and has the advantage of lowering costs. Marble production generates large amounts of waste. Recycling of such wastes by incorporating them into ceramic industry is a practical solution for pollution problem. The aim of this work is to assess the possibility of the recycling of marble wastes in the production of stoneware clay bodies as a raw material for ceramic artwork production. Five different clay body mixes containing marble waste up to 27% were prepared and evaluated for firing color, water emission, morphology, microstructure, thermal expansion coefficient and thermal behavior. The results of the tests show that the utilization of marble waste in stoneware body is feasible for ceramic artwork production.     

Optimization of wastes content in ceramic tiles using statistical design of mixture experiments

Mineral extraction and processing industries have been cited as sources of environmental contamination and pollution. The inclusion of wastes into productive cycles represents an alternative form of restoration, which is interesting from both environmental and economic standpoints. In this work, the development of ceramic tile formulations containing kaolin processing and granite sawing wastes was investigated using the statistical design of mixture experiments methodology. Ten formulations using the raw materials, red clay, kaolin processing and granite sawing wastes, were selected and used in the mixture design. Test specimens were fired and characterized to determine their water absorption, linear firing shrinkage and modulus of rupture. Regression models were calculated, correlating the properties with the composition. The significance and validity of the models were confirmed by statistical analysis and verification experiments. The regression models were used to optimize the waste content in ceramic compositions. The results showed that formulations containing up to 62% of waste could be used in the production of ceramic tiles.     

The use of sewage sludge and marble residues in the manufacture of ceramic tile bodies

The substitution of clayey raw materials for other wastes, in this case urban sewage sludge and marble sludge, in the production of traditional ceramics could be cost effective from the utilisation and recycling of these wastes as a secondary raw material. At the same time, it can be helpful in tempering the environmental problems associated with such wastes. This research shows the results of the addition of marble sludge and urban sewage sludge in different proportions to clay in a ceramic body. The most suitable products were selected regarding the mineralogical composition of the resulting ceramic material and its technological behaviour. To evaluate the ceramic properties of the obtained material, several processing and product properties (linear contraction, water absorption, bending strength) were determined. With regard to the technological properties of the final ceramic bodies, there does not seem to be any clear relation between the linear contraction values and the content of residue. However, the increase in water absorption along with the increase in the residue content is evident. The addition of residue decreased the bending strength. The selection of the adequate content of sludge to be added to the ceramic body will be controlled by the usual standards applied to construction materials.     

The effects of fine fire clay sanitaryware wastes on ceramic wall tiles

In the last decade, environmental preservation has become an important issue. Specifically, recycling of sanitaryware fine fire clay (FFC) waste is important for reducing costs. In this study, the use of FFC waste as an alternative raw material in the production of ceramic wall tiles was investigated. Five ceramic wall tile bodies were prepared by substituting kaolin (max. 15 wt%) with FFC wastes. All formulations were mixed, pressed into pellets and sintered at 1145 °C. The sintering behaviour was evaluated using an optical dilatometer. Water absorption, linear shrinkage and bending strength were also measured. This study revealed that FFC wastes are good alternative raw materials, and the corresponding formulations were shown to be viable in the manufacturing of ceramic tiles. The most remarkable conclusion from this study was that the addition of FFC waste decreased moisture expansion.     

Coloring effect of iron oxide content on ceramic glazes and their comparison with the similar waste containing materials

The effects of adding iron oxide to ceramic glaze formulations were studied in this study. Iron oxide was added in different weight ratios into the reactive transparent glaze, reactive opaque glaze, and transparent glaze formulations. The iron oxide content in the glaze composition, the coloring mechanisms, the phase distributions, and surface properties at temperatures of 950–1000-1050-1200 °C in the oxidation firing medium were investigated. Scanning Electron Microscopy (SEM) to determine the microstructural and morphological characterizations of the test glazes, X-Ray Diffractometry (XRD) to determine the crystallographic properties and phases, and X-Ray Fluorescence (XRF) analyses to determine the elemental and chemical composition were performed. In addition to these, surface images were examined with Digital Microscope (DM) and Commission Internationale de l'Eclairage (CIE) L*a*b, and water absorption values were compared. In addition, taking into account environmental factors, a comparison of ceramic glazes with the same amount of waste iron oxide was also performed for same purpose. As a result of the studies, it was observed that the addition of iron oxide and/or waste iron oxide did not have a negative effect, and coloring effects on the glaze layer were observed at different rates and firing temperatures.     

低温陶瓷釉的制备

低温烧结工艺是目前陶瓷行业节约能源、降低燃耗、提高生产效率的有效途径,因此在低温条件下烧制陶瓷釉逐渐成为研究热点。为大幅度降低烧结温度,采用磷酸钠代替基础釉中的二氧化硅的方法,促使液相在低温形成,成功研制了烧成温度为890 ℃的基础釉。当磷酸钠质量分数达到33.25%时,基础釉的烧成温度降低了290 ℃。采用场发射扫描电镜分析了样品的表面和断口形貌,实验结果表明磷酸钠能够显著降低陶瓷釉的煅烧温度。通过在基础釉中加入显色剂,实现了在低温下制备红色陶瓷釉,并且烧成温度降低了350 ℃。实验结果表明,磷酸钠在低温陶瓷釉的制备过程中起到降低温度的重要作用。这些研究结果有助于彩色陶瓷釉的研制。     

Floor tile glass-ceramic glaze for improvement of glaze surface properties

Simultaneous improvement of surface hardness and glossiness of floor tile glaze, without changing its firing temperature, was the main purpose of the present paper. Thus, various glazes in the system of CaO–MgO–SiO₂–Al₂O₃–ZrO₂ were prepared and their crystallization behaviors within a fast firing cycle were investigated. With increasing amounts of calcium and magnesium oxides to base glass, the optimum glass-ceramic glaze was obtained. The results showed that with increasing of CaO and MgO part weights in frit, the crystallization peak temperature was gradually decreased and the intensities of diopside and zirconium silicate were increased. The comparison of micro hardness for the optimum glass ceramic glaze derived in this work with a traditional one used in floor tile industries indicates an improvement of 21%. It was found that the glaze hardness not only depend on the amount and type of crystalline phases, but also on the residual glass composition. Furthermore, it was observed that the glaze micro hardness is only slightly affected by thermal expansion mismatch of body and glaze.     

Granite waste and coffee husk ash synergistic effect on clay-based ceramics

Brazil produces massive amounts of granite sawing waste and coffee husk ash and their inadequate and, often, illegal disposal causes enormous environmental problems. In the past decade, these and other industrial wastes have been intensively studied aiming at determining their potential as alternative raw materials, particularly for the ceramic industry. This work describes research carried out on the joint incorporation of those wastes in ceramic roof tile formulations. The results indicated that the simultaneous use of both materials translates into a very forgivable industrial working range, both composition- and temperature-wise, which, given the technological properties values observed after firing at 1100°C, enables industrial up-grade to wall tile production. As collateral benefits, the use of granite waste and coffee husk ash as alternative raw materials in the manufacture of clay-based products will relieve the stress on feldspars consumption and attenuate waste disposal concerns.     

New waste-based clinkers for the preparation of low-energy cements. A step forward toward circular economy

This paper describes the use of industrial wastes arising from different production processes of the ceramic and marble industries as raw materials for the design and formulation of new cement clinkers with a high content of dicalcium silicate (Belite). The aim was to reintroduce these wastes in the industrial sector and take advantage of them for a greater environmental benefit, as indicated by the principles of the circular economy. Formulations containing 2.5, 5 and 10 wt% of chamotte and marble sludge, respectively, and a waste-free formulation have been designed to obtain clinkers with a content of dicalcium silicate higher than 60 wt%. The different blends have been studied up to a maximum temperature of 1390°C by Thermal Analysis. Other techniques such as XRD, XRF, Modified Bogue Equation, Quality Indexes (LSF, AM, SM) and Optical Microscopy have been used for the study and characterization of industrial wastes, the raw materials and the high belite-type cement dosages. The results indicate that this type of cements can be designed using different types of wastes and in this way reduce the environmental impacts caused by the extraction of raw materials and the deposition of the wastes in landfills, improving the circular economy of the construction industry.     

Preparation and characterization of glazes from combinations of different industrial wastes

The work reported here involves the preparation and characterization of ceramic glazes made from combinations of different industrial wastes. The wastes were float glass, granite and lime shale (a raw material waste from the oil shale industry in São Mateus do Sul, state of Paraná, Brazil), which were used to replace natural raw materials in a proportion of up to 50% in weight. The compositions were formulated using the Seger method and prepared by conventional ceramic processing. The stabilized suspensions were applied in commercial wall tile and porcelain stoneware tile, which were sintered at temperatures of 1080 °C and 1150 °C, respectively, using two different heating cycle. Three compositions were developed, two of which yielded opaque glazes and one a transparent glaze. Linear thermal expansion coefficients (α) of 80.10^?7 °C^?1 to 100.10^?7 °C^?1, and glaze softening temperatures of 600–700 °C were characterized by dilatometric analysis. The glaze compositions showed chemical resistance against acid and alkaline attack after 96 h, showing a mass loss of less than 0.1% in weight. The surface hardness of the glazes determined by the Mohs scale, Vickers microhardness and abrasion resistance (PEI indices) were between 6–7, 3–3.7 GPa and 3–4, respectively. These properties are compatible with those of commercial glazes for wall tiles and porcelain stoneware ceramics.     

Mechanical and thermal studies on epoxy toluene oligomer‐modified epoxy resin/marble waste composites

In this research, marble dust waste was recycled as raw material for the preparation of composite materials. Epoxy toluene oligomer (ETO) was synthesized from toluene and epichlorohydrin, which was used as a comatrix in 50 wt% with commercial epoxy resin (ER). Its chemical structure was characterized with Fourier transform infrared spectroscopy and chemical analyses. The rigid filler used in epoxy polymer matrix was the marble processing waste obtained from wastewater using different coagulants, such as sepiolite, zeolite, or pumice. The thermal and mechanical properties of the composites were evaluated with thermogravimetric and mechanical analyses. The results showed that the marble wastes with all coagulants can significantly improve the thermal stability of an ER–ETO matrix at temperatures above 350°C. Composites exhibited a higher thermal degradation temperature with a much higher char yield. Surface hardness and tensile strength of the composites were higher than those of pure epoxy polymer matrix, as well. Scanning electron microscopy was used for the characterization of surface and cross‐sections of the composites to verify the results. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers     

Extrusion and property characterisation of waste-based ceramic formulations

This work describes the studies carried out with various industrial wastes and natural sub-products based on the SiO₂–Al₂O₃–CaO system, aimed at extruding all-waste ceramic products of industrial interest. Four waste materials were selected and characterised, namely, (i) Al-rich anodising sludge (A-sludge), (ii) sludge from the filtration/clarification of potable water (W-sludge), (iii) sludge generated in marble sawing processes (M-sludge), and (iv) foundry sand (F-sand).The plastic behaviour of two different all-waste formulations was first characterised by stress–strain curves and then, after prior adjustment of the plasticity level, the effect of the ram speed and extrusion pressure was evaluated using the Benbow–Bridgwater's model for paste extrusion. Using the waste-based formulations with additives and tube-dies of different die-land dimensions, a good agreement was demonstrated between predicted and measured values. The differences in the static friction coefficient give an effective indication of the surface quality of the extrudate.Extruded rods were then fired at several temperatures and characterised in terms of relevant functional properties (shrinkage, density and mechanical strength). Compositional evolution was assessed by X-ray diffraction. Since interesting performances were observed, the potential of the use of wastes in ceramic formulations of industrial interest was confirmed.     

利用陶瓷废渣生产绿色陶瓷产品

本文研究了利用陶瓷废渣生产绿色陶瓷产品.在对陶瓷废渣特性识别的基础上,通过对原矿原料、半熟料废渣、熟料废渣的性能检测,确定最佳配料配方;通过采用低温快烧技术,开发使用坯体增强剂,实现了废水、废渣零排放,废气污染物大幅下降,使废渣使用比例达到80%以上,生产出性能优于GB / T4100-2006标准的绿色陶瓷产品.     

磷矿渣用于陶瓷坯料试验研究

磷矿渣作为工业废料,其合理利用极具经济价值,根据其组成特点,适当配合其它原料,经试验证明,完全可以用于陶瓷产品的坯料配制,再配以高强乳浊釉对有色坯体进行有效的遮盖,则可以生产出各项性能指标符合要求的釉面砖制品。     

辉石矽嘎岩于陶瓷生产中的应用

介绍了辉石矽嘎岩处理废渣的矿物组成、化学组成和粒度组成,叙述了这种废渣于陶瓷砖、颜料和釉及过滤材料生产中的试验应用情况。     

超耐磨高硬度全抛釉的制备研究

针对目前全抛釉砖产品存在的釉面耐磨性差、硬度小、坯釉结合性差及防污能力差的不足,通过采用成熟温度高的生料釉作为面釉和烧成温度低的熔块釉作为底釉制备了全抛釉。通过底釉和面釉釉料的配方组成优化和调整釉料熔融性能及制备工艺等,研制出超耐磨、高硬度的全抛釉,有效提升了全抛釉砖产品质量。     

日用陶瓷釉面耐磨性增强技术的研究进展

日用陶瓷在运输和使用过程中釉面容易磨损,产生各种划痕,影响日用陶瓷的美观和使用性能。提高日用陶瓷釉面的耐磨性,对开发高品质耐磨日用陶瓷、提升我国日用陶瓷产品的品质具有重要意义。笔者分析了日用陶瓷釉面的结构特征、影响釉面耐磨性的主要的因素,探讨提高釉面耐磨性的途径和方法。     

Materials and technological evolution of ancient cobalt-blue-decorated ceramics: Pigments and work patterns in tin-glazed objects from Aragon (Spain) from the 15th to the 18th century AD

Cobalt-blue-decorated ceramics with tin glazes have been produced in the Iberian Peninsula since the 14th century AD and in Aragon region since the 15th century until the present time. An important ceramic trade was developed and relations with potters of other important production centres were established. Representative objects from archaeological findings could help in drawing conclusions on the technology used in the manufacture of blue-decoration ceramics. In this work, the composition of bodies and glazes of more than fifty samples of blue-decorated ceramics from Aragon was determined by ICPAES and EDX–Scanning Electron Microscopy (SEM). Based on this information, different ceramic groups could be appreciated and reference values valuable for the subsequent study of the blue decorations by means of other techniques, such as laser ablation (LA)–ICPMS, were also obtained. In particular, the data obtained permitted to unequivocally establish the use of three different types of cobalt pigments, with clear changes between areas and periods. Moreover, it is demonstrated that this evolution in the nature of the blue pigments was related to a different procedure when decorating the object, namely the application of the pigments and the drawing the designs before (under glaze) or after (on glaze) covering the ceramic with the tin glaze.     

Potential use of Kraft pulp mill and flat glass cutting wastes in red ceramic products

This study assessed the incorporation of green liquor dregs, an inorganic solid waste from Kraft pulp mill, and flat glass cutting waste (FGCW) into red ceramic formulations. Since in Brazil sanitary landfills are still the main destination of industrial wastes such as those used in this research, a survey was conducted to identify the number of landfills in the region of origin of each waste and the amount of waste that could have this destination avoided. The effects of firing temperature and simultaneous incorporation of both industrial wastes were analyzed to optimize heat treatment and waste content in the formulation to manufacture red ceramic products. The influence of green liquor dregs and FGCW incorporation into clayey mass was evaluated varying waste content between 0 and 50 wt%. The specimens were prepared by uniaxial pressing, fired at 850 and 950 °C, and had their physical-mechanical properties and mineralogical and microstructural characteristics analyzed. The best results were obtained for the formulation with 10 wt% green liquor dregs and 30 wt% FGCW fired at 950 °C. This result highlights the potential of using green liquor dregs, a waste difficult to be recycled due to its chemical composition, associated with FGCW, which acts as a fluxing agent in ceramic formulations.