| 摘要 |
PURPOSE: To substantially completely and inexpensively decompose cyanides by wet- oxidizing a cyanide-contg. waste water under specified temp., pressure and oxygen amt., removing sludge, etc., to obtain a primary treated liq., adding a sulfur compd. to the treated liq. and wet-oxidizing the treated liq. in the same way. CONSTITUTION: A cyanide-contg. waste water in a waste water storage tank 1 is boosted to a specified pressure by a pump 2, an oxygen-contg. gas is supplied from a compressor 22, and the waste water is sent to a heat exchanger 3 and heated to >=100 deg.C. Then, in a primary reaction tower 5, the waste water is wet-oxidized in the presence of oxygen in the amt. less than the stoichiometry necessary to make the cyanide compd., nitrogen compd. and org. and inorg. substances harmless. The sludge and metallic component are removed in a solid-liq. separator 10 to obtain a primary treated liq. Sulfuric acid is added to the primary treated liq. from a sulfuric acid storage tank 25, and the treated liq. is sent to a secondary reaction tower 14 packed with a catalyst with metal and metallic compd. as the active components and wet-oxidized at >=100 deg.C in the same way as before. The treated liq. is sent to the heat exchanger 3, utilized as the heat source and then discharged through a gas-liq. separator 16. |
