Treating method for cyanide waste water

Abstract

The invention discloses a treating method for cyanide waste water. The method comprises three steps of electrochemical treatment, coagulating sedimentation treatment and bioactive carbon treatment; cyanide which is easy to treat is removed through the electrochemical treatment method first; coagulating sedimentation is conducted by adding a zinc sulfate solution and a coagulating agent to remove metal cyanogen complex compounds and heavy metal ions in the waste water; pollutants which are difficult to remove by the chemical methods in the waste water are removed according to a biological and physical adsorption method in the bioactive carbon treating system finally. According to the characteristic that the pollutants in gold mine cyanide waste water are complex and difficult to treat, the method integrates the electrochemical treatment technique, the coagulating sedimentation technique and the bioactive carbon treatment technique together to synergistically conduct advanced treatment on the gold mine cyanide waste water, and is good in treating effect, high in treating efficiency, stable in operation of the system, simple in technological process and convenient to realize industrial application; the treated waste water can be returned to a manufacturing technology process to be used as reused water or discharged after reaching the standard.

Description

technical field [0001] The invention relates to a pollutant treatment method in the field of environmental protection, in particular to a treatment method for gold mine cyanidation wastewater. Background technique [0002] Due to the use of cyanide gold extraction process in the production process of gold mines, a large amount of cyanide wastewater will be produced. This part of cyanide wastewater not only contains a certain amount of highly toxic cyanide, but also contains thiocyanate, COD, copper, and zinc. , lead and other heavy metal ions, if not effectively dealt with, will produce major environmental hazards. At present, the methods commonly used at home and abroad to treat cyanide wastewater include acidification recovery method, alkali chlorine method, Inco method, sulfur dioxide method, etc. Although the acidification recovery method can recover a certain amount of cyanide, due to the incomplete recovery of cyanide, the wastewater There will be a certain amount of ...

AI Technical Summary

Problems solved by technology

[0002] Due to the use of cyanide gold extraction process in the production process of gold mines, a large amount of cyanide wastewater will be produced. This part of cyanide wastewater not only contains a certain amount of highly toxic cyanide, but also contains thiocyanate, COD, copper, and zinc. , lead and other heavy metal ions, if not effectively treated, will cause major environmental hazards

At present, the methods commonly used at home and abroad to treat cyanide wastewater include acidification recovery method, alkali chlorine method, Inco method, sulfur dioxide method, etc. Although the acidification recovery method can recover a certain amount of cyanide, due to the incomplete recovery of cyanide, the wastewater A certain amount of cyanide will remain in the medium, and at the same time, thiocyanate and some heavy metal ions have not been effectively removed

After the alkali chlorine treatment, a large amount of residual chlorine will remain, and ClCN products will be produced, causing secondary pollution problems. At the same time, heavy metal ions such as copper, zinc, and lead in the wastewater have not been effectively treated.

Although the Inco method and the sulfur dioxide method can make the treatment of cyanide meet the standard, the thiocyanate in the wastewater cannot be treated. In addition, there are many waste residues generated during the treatment of heavy metals, which is likely to cause secondary pollution

Therefore, there is still a lack of ideal methods for the treatment of cyanide wastewater. If this problem can be solved, it will be of great significance to the development of my country's gold production and environmental protection.