Substitution of the clayey mineral component by lignite fly ash in portland cement clinker synthesis

Abstract

Fly ash from four power plants in Serbia (PP "Morava" - Svilajnac, PP "Kolubara" - Veliki Grijani, PP "Kostolac" - units B1 and B2 - Kostolac and PP "Nikola Tesla" - units A and B - Obrenovac) was utilized as the starting raw component for Portland cement clinker synthesis. Limestone and quartz sand from the "Holcim - Serbia, a.d." cement factory were the other two starting raw components. Based on the chemical composition of the raw components and from the projected cement moduli, the amounts of raw components in the raw mixtures were calculated. Six different raw mixtures were prepared - each one consisted of limestone, sand and different fly ash. A raw mixture from the industrial production of the "Holcim - Serbia, a.d." cement factory was used as the reference material. The prepared raw mixtures were sintered in a laboratory furnace at 1400?C. The chemical and mineralogical compositions of the synthesized clinkers were determined. The characteristics of clinkers, based on fly ash, were compared to the characteristics of the industrial Portland cement clinker from the "Holcim - Serbia, a.d." cement factory. The results of the investigation showed that fly ash from power plants in Serbia can be suitable for Portland cement clinker synthesis.