INORGANIC HARDENED MATERIAL

摘要

PROBLEM TO BE SOLVED: To obtain a material for civil enginnering/construction, by baking a material to be incinerated such as municipal waste, sewage sludge, etc., to give incinerated ash, rebaking the incinerated ash to give a part of raw material so that an organic component, chlorine, heavy metal, etc., contained in the material to be incinerated are removed. SOLUTION: Incinerated ash obtained by incinerating municipal waste, etc., is rebaked at a temp. of >=1,000 deg.C, generally 1,000-1,400 deg.C to vaporize and to remove a heavy metal, a hardening inhibiting substance, dioxin, etc. The vaporized heavy metal is recovered in a post-processing. The baked ash obtained by baking the incinerated ash may be treated as it is with a chelating agent or an alkali and used. The baked ash is mixed with a cement hydrate, gypsum or calcium silicate alone or its combined material as a matrix phase to give a hydraulic composition. The hydraulic composition comprises gypsum and a baked material containing 10-40 wt.% C11 A7 CaCl2 and C2 S and C3 S. Preferably a material using a waste is used as a cement to reduce the cost and to effectively use a resource.