Fly ash building material

摘要

Fly ash has a content of 3-15% by weight SO3 and 40-90% active ingredients which are SO3 free & 100% active. The latter comprises by weight %, 8-25 SiO2, 18-45 Al2O3 + Fe2O3, and 35-75 CaO + MgO. The mixture is bound with water at 50-90 C, pref. 60-80 C, & the building material is obtained in less than 24 hrs. Specifically, the fly ash is lignite or oil shale filter ash.