| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve the efficiency of recovering valuable metal, particularly, copper by blowing oxygen into a metal layer as the lower layer of slag formed in melts of incineration ash, oxidizing iron metal to increase the content of valuable metals, then granulating the molten slag and the metal layer, and separating the metal from the pulverized material by utilizing the difference in specific gravity. SOLUTION: A required amt. of incineration ash is subjected to melting treatment at 1350 to 1650 deg.C, and in the case the grade of copper in the recovering metal layer is 15%, the molten slab and metal are extracted from the same furnace outlet and are continuously granulated, and the metal and other granulated material are separated by a gravity concentrating method. Furthermore, in the case the grade of copper in the recovering metal layer is less than 15%, oxygen (or air) is blown into the metal layer formed in the process of the melting treatment, and iron metal is oxidized and is formed into slag, by which the grade of copper in the remaining layer is increased to >=15%, and they are granulated and separated. Moreover, as the gravity concentrating method, the method utilizing the facts that the slag true specific gravity is 3g/cm<3> and the metal true gravity is 7g/cm<3> is optimum.</p> |
