PROBLEM TO BE SOLVED: To provide a method for efficiently suppressing elution of hexavalent selenium in a water washing treatment of cement kiln extracted dust. SOLUTION: This is a method for suppressing elution of hexavalent selenium from cement kiln extracted dust, in which the cement kiln extracted dust is washed with water using washing water to which an acid has been added in advance. The amount of the acid added is preferably 0.1 mol or more and less than 0.8 mol in terms of monovalent acid with respect to 100 g of cement kiln extracted dust. Further, the ratio of the cement kiln extracted dust to the washing water is preferably 1 or more and less than 100 in terms of the mass ratio of water / cement kiln extracted dust. The acid is preferably hydrochloric acid or nitric acid. [Selection diagram] None
展开▼
