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The production of tiling and building ceramics is based mainly on the traditional system clay-silica-feldspar. However, in recent decades it has been demonstrated that some of these raw materials can be successfully replaced by various industrial wastes. Because of the high feldspars price a significant part of these studies was based on the usage of different alternative “amorphous” fluxes (as glass culets, TV cathode ray tubes, basaltic tuffs and others). Unfortunately, the addition of similar materials in amoun...

The aim of this work is the optimization of sinter-crystallization regime of a glassceramic from a municipal solid waste incineratior (MSWI) bottom ash. The parent waste was melted at 1400oC, milled below 75 $\mu$m and the obtained glass powders were pressed at 100 MPa. The optimal temperature for sinter-crystallization was estimated by DTA, dilatometry and XRD. Subsequently, the degrees of sintering, obtained at different heating rates (between 2 and 40oC/min) and 1 h step at 950oC were estimated by the linear sh...

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 possibility to obtain a low cost petrurgical material by direct sintering of alkaline basaltic tuffs is demonstrated. The parent rock was milled for 10-15 min and the resulting powder was pressed at 100 MPa. The sintering and the phase formation in air and inert atmospheres were studied by dilatometry and DTA, respectively. The phase composition of obtained samples was evaluated by XRD whereas the stricture was highlighted in details by SEM. Some mechanical and thermal properties of the new materials were meas...

The sintering and phase formation of glass press-powders, obtained after melting and re-melting of MSW bottom ash, were investigated by non-isothermal dilatometry and differential thermal analysis. Additionally, a series of composite materials, containing 20 vol \% corundum powders with different fraction size, were prepared and studied. The crystalline phases, formed at different temperatures, were evaluated by X-ray diffraction and the structure of glasses and final materials were observed by scanning electron m...

The work discuses three ceramic compositions containing no feldspars and based on 30, 50 and 70 wt \% Blast Furnace Slag (BFS), respectively, 30 \% kaolin and quartz sand. Initially, the processes of phase formation and densification were estimated using nonisothermal Differential Thermal Analysis and Dilatometry. After that, the degree of sintering at different temperatures and times was measured by linear shrinkage and water absorption. The phase composition and the structure of final materials were evaluated wi...

Alkaline basaltic tuffs, BT, from southern Turkey were characterized and used to obtain cheap sintered glass-ceramic and ceramic materials. The chemical and mineralogical compositions were analyzed by fluourescene spectrometry and X-ray diffraction analyses, respectively. The phase formations were studied by DTA, while the sintering behavior – by differentional dilatometer. The structure of the sintered samples was evaluated by pycnometric techniques and observed by SEM. Due to its high porosity and low crystall...

The present work discusses the synthesize of sintered granite–like glass-ceramics obtained by vitrification of hazardous industrial wastes. The chemical resistance of parent wastes and glasses were classified by the toxic characteristics leaching procedure (TCLP), whereas the crystallization behaviour was evaluated by DTA and XRD. The thermal and mechanical properties of final glass-ceramics were also measured and discussed. The obtained glass-ceramics have attractive appearance, elevate chemical durability and ...

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 mecha...