Durability of new blended cements additioned with recycled biomass bottom ASH from electric power plants

Abstract

This study explores the effect of replacing 10% and 20% of portland cement with BBA from three biomassfired power plants on new design cement sorptivity, capillary absorption, electrical resistivity, drying shrinkage, expansion and heat of hydration. The findings show that although this addition induces an increase in water uptake due to its effect on the pore system, it does not compromise cement quality, which is international recommendation-compliant. As these new cements have the same or higher resistivity than the reference material, they are at least as corrosion-resistant as OPC. Binders bearing BBA exhibit less shrinkage and swelling than conventional cement and their peak heating, rate of heat release and total heat flow values are lower, particularly at the higher replacement ratio. The conclusion drawn is that the durability of the recycled product, which qualifies as a strength class 42.5, type II/A cement, is unaffected by the partial replacement of clinker with BBA