| abstract |
(57) [Summary] [Problem] Development technology for applying sulfur oxide-containing volcanic ash, which has been squirted in large quantities and suffering from disposal disposal, such as volcanic ash from Miyakejima, to useful products with a large demand has been completed. Absent. In addition, Portland cement, which is a hydraulic hardening material in the prior art, contains harmful heavy metal chromium, which is a problem. In addition, in the case of the water glass-based solidified material, the solidified body at room temperature curing does not have water resistance and is not practically used. Accordingly, there is a demand for the production of an inexpensive hydraulically solidified material that can be hydraulically solidified at room temperature with non-polluting materials. SOLUTION: The activated silicate which has been recovered in advance by a two-stage activation treatment of a sulfur oxide-containing volcanic ash by a heat treatment with a calcium hydroxide composition and a reaction treatment with an alkali hydroxide is preferably used as a calcium salt composition, Accordingly, the present invention provides a method for producing a pollution-free hydraulic hardening material composed of a powdered one-pack composite composition by uniformly mixing the auxiliary composition. |