The role of a coal gasification fly ash as clay additive in building ceramic

The clean coal integrated gasification in combined cycle (IGCC) technology of electrical power generation is different than conventional process in combustible treatment which generates inorganic wastes in the form of glassy slag and fly ash with singular properties. We have studied the fly ash coming from ELCOGAS IGCC power plant as additive to clays for building ceramic fabrication. The addition of this new kind of fly ash to a clay of medium plasticity to elaborate pressed specimens, that were baked at 900 degrees C, improves the sintering of the paste and consequently an improvement of absorption, saturation and mechanical properties of the fired bodies, with no negative effects on shrinkage, colour alteration or efflorescence. In contrast, this fly ash does not mend the excessive firing shrinkage when added to a clay of a high plasticity index. (c) 2006 Elsevier Ltd. All rights reserved.