The chemistry of Portland cement-gasifier slag interactions

Gassifier slag (GS) is a potential new cement replacement material which is intermediate in composition between granulated blastfurnace slag (GBFS) and pulverized fuel ash (P FA). Three GSs have been blended with an ordinary Portland cement (OPC) and a sulphate-resisting Portland cement (SRPC) , and comparisons made with a G BFS and a P FA blended with the two cements. Several techniques have been used to investigate the slag-cement interactions in both the early and later stages of hydration. The results indicate that, like GBFS, GS cements show latent hydraulic activity, particularly in the early stages of hydration, while, as with PFA, pozzolanic activity dominates in the later stages.