Process and equipment for treating wastewater containing cyanide ions

Abstract

The invention discloses a process and equipment for treating wastewater containing cyanide ions. The equipment comprises a security filter, an ion exchanger loaded with cyanogen removal resin, a water injector and a sedimentation tank body. The process comprises the following steps of: after the wastewater is pre-filtered, adsorbing the cyanide ions by the cyanogen removal resin; after the cyanogen removal resin adsorbs the cyanide ions to be saturated, carrying out elution; sucking out hydrocyanic acid formed after elution under negative pressure formed at an outlet of the water injector; and mixing the sucked hydrocyanic acid and cuprous salt solution injected by the water injector to perform a reaction to form copper cyanide precipitates. The process has the principle that the cyanide ions in the wastewater are reduced by an enrichment method, and does not adopt a dispensing or electrolyzing mode just like the conventional method, and thus, the process does not need to consume any energy resources and is more environmental-friendly and the mineralization of water cannot be increased in the whole technological process.

Description

technical field [0001] The invention relates to a wastewater treatment process and corresponding equipment, in particular to a process and equipment for treating cyanide-containing wastewater. Background technique [0002] Cyanide is widely used as the best complexing agent in electroplating. Cyanide has a very high complexing ability, and can form complexes with zinc, cadmium, copper, silver, gold, etc. The cyanide electroplating solution composed of cyanide complexes has excellent performance. However, due to the strong toxicity of cyanide, when cyanide is inhaled into the human body in excess, it will cause human poisoning and seriously endanger life. Therefore, it is necessary to remove cyanide from the wastewater after electroplating. The existing treatment method for wastewater containing cyanide ion is generally to ion exchange resin CN - Ion exchange resin for cyanide treatment, one is oxidation method, such as using alkaline chlorination method, that is, adding ch...

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Problems solved by technology

However, due to the strong toxicity of cyanide, when cyanide is inhaled into the human body in excess, it will cause human poisoning and seriously endanger life. Therefore, it is necessary to remove cyanide from the wastewater after electroplating.

The existing treatment method for wastewater containing cyanide ion is generally to ion exchange resin CN - Ion exchange resin for cyanide treatment, one is oxidation method, such as using alkaline chlorination method, that is, adding chlorine-based oxidant to cyanide-containing wastewater to partially oxidize cyanide into less toxic cyanate. One-step complete oxidation into carbon dioxide and nitrogen, the disadvantage of this method is that it needs to prepare a large amount of oxidant, which causes energy waste, and adding medicine to wastewater will increase the salinity of wastewater; another method is electrolysis, which is also a counter ion Exchange resin CN - Ion exchange resin is oxidized to achieve cyanide treatment, and this method also consumes a lot of energy

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