| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for separating, from iron and steel slag as raw material, Ca, Fe and Mn constituting the iron and steel slag and recovering each element as a useful component. <P>SOLUTION: The method for producing dihydrate of plaster and oxides or hydroxides of Fe, Mn includes: (1) a first step of dissolving iron and steel slag into sulfuric acid; (2) a second step of recovering plaster and silica from the sulfuric acid to which the iron and steel slag is dissolved; (3) a third step of evaporating the moisture in the sulfuric acid from which plaster and silica are recovered and roasting the resulting powder; (4) a fourth step of dissolving the roasted powder into water to recover Fe oxide insoluble to water; (5) a fifth step of evaporating the moisture in an aqueous solution to which the roasted powder in the fourth step is dissolved, and roasting the resulting powder; and (6) dissolving the roasted powder into water to recover Mn oxide insoluble to water. <P>COPYRIGHT: (C)2013,JPO&INPIT |
