Bonding of high fly ash content ceramic bodies at low temperatures

Abstract

Utilization of fly ash in higher volumes is a difficult problem in producing building materials due to its non-plastic nature and inadequate physicomechanical properties in the temperature range of 1000°-1100°C. It is reported that maximum 50-70 wt% of fly ash can be effectively utilized to manufacture various items for building industries, the remaining constituent being high plastic clays. In the present study, an attempt has been made to bond 80-95% ESP. grade fly ash in the temperature range of 1000°-1100°C using different kinds of synthetic binders at various levels of pH. The physico-mechanical properties for the developed samples are discussed in this paper. It has been observed that small addition of such binders reduced the percent water absorption values to the level of 17- 0.16% from the respective values of 33-11% without binder in the temperature range of 1000°-1100°C. Also addition of such binders significantly improved the cold crushing strength values both in green and fired stages, The paper finally discusses some of the possible applications of the developed compositions in the area of building industries.