| 摘要 |
PURPOSE:To enhance the removal efficiency of heavy metal ions at the time of thermal hydrolysis and to reduce the concn. of cyanide and the concn. of org. pollutants to a certain degree before thermal hydrolysis treatment by applying electrolytic treatment to a cyanide-containing waste solution as pretreatment before thermal hydrolysis treatment. CONSTITUTION:In the thermal hydrolysis pretreatment of a cyanide-containing waste solution containing heavy metal ions, as pretreatment before the thermal hydrolysis treatment of the cyanide-containing waste solution, the cyanide-containing waste solution is subjected to electrolytic treatment. This cyanide-containing waste solution containing heavy metal ions is an electrolyte solution and, by subjecting the waste solution to electrolytic treatment, oxidation reaction such as the generation of oxygen is generated on the surface of an anode and the precipitation reaction of a metal is generated on the surface of a cathode. Further, a complex cyanide compd. of a heavy metal in a solution is decomposed into free cyan and the heavy metal and, by the precipitation reaction of the heavy metal on the cathode, the heavy metal is precipitated on the cathode or in the vicinity thereof in an alloy form. This reaction of the cathode is reductive reaction incapable of being generated in usual chemical reaction and becomes possible for the first time by electrolytic treatment. |
