Composite cement containing circulating fluidized bed ash and concrete composition containing said ash

摘要

A cement composition includes fly ash from a fluidized bed and a cement or clinker. The fly ash composition (by wt) is such that : (A) the sum of the silicon, aluminum, iron and calcium oxides is at least 60; (B) the SO3 is 3-40; (C) the CaO is 5-60; (D) the SiO2 is 4-60; (E) the Al2O3 is 1-35; (F) the Fe2O3 is 0-15; (G) the SiO2 and Al2O3 are in the form of dehydroxidized quartz and clay and the CaO and SO3 in the form of quicklime and anhydrite (CaSO4); and (H) the SO3 content of the cement compound is = 5. An independent claim is also included for concrete incorporating this cement composition.