Hardened cement material from coal flue gases - scrubbed with alkaline earth hydroxide, giving suspension of fly-ash and alkaline earth hydroxide and sulphite

摘要

The title material comprises the set hardened reaction prods. of 0.25-70 alkaline-earth hydroxide 10-99.5 or fly ash and 0.25-70 wt.% alkaline-earth sulphate. Coal-burner flue gases are desulphurised by chemical treatment in a scrubber yielding an aq. suspension of alkaline-earth carbonates, hydroxides or oxides, and this suspension is treated by removing water and adding fly-ash and alkaline earth hydroxides, the solids content of the treated suspension being 30-90 wt.%. The material is opt. shaped into granules which are kept until they harden sufficiently for use as aggregate.