The products of a high temperature reaction of fly ash with lime and soda

Abstract

Abstract A composition of coal combustion fly ash depends on a coal composition and conditions of a combustion process. The main components are SiO2 and Al2O3. An amount of Al2O3 in coal combustion fly ash is relatively high, about 30–40%, and for this reason, the fly ash could be potentially used as a raw material source for alumina production. There are several ways to get alumina. The fly ash could be acid leached or sintered with a suitable additive. One of the possible sintering processes is lime-soda sinter process. The article deals with products of lime-soda sinter process of the fly ash produced from brown coal in Czech thermal power plant. The phase composition of sintered material was determined by X-ray diffraction analysis (XRD). The presence of sodium aluminate and dicalcium silicate was confirmed.