| 摘要 |
<p>PROBLEM TO BE SOLVED: To recover effective resources and to make harmful waste harmless by decomposing the raw sludge separated from an electrolyte consisting essentially of SnCl2 , reducing the recovered white sludge and casting the separated metallic tin into an anode. SOLUTION: A steel strip as a cathode is electroplated with metallic tin as an anode in a plater holding an electrolyte consisting essentially of SnCl2 . In this device for producing an electrotinned steel sheet by a halogen process, the electrolyte contg. Sn<2+> is extracted from the plater, and the sludge is separated by an equipment, regenerated and circulated. The separated raw sludge is filtered by a decomposition device into a soln. and solid blue sludge. The soln. is allowed to react with NaOH, and white sludge consisting essentially of solid SnO2 is obtained in a recovery device. The white sludge is reduced with carbon in a refiner, and the formed metallic tin is separated from iron and introduced into a casting equipment. Meanwhile, the blue sludge is added with CaCl2 in a treating device, hydrolyzed in an autoclave and discarded as iron sludge, CaF2 , harmless liq. and gas, etc.</p> |
