Electroplating wastewater zero-discharge or low-discharge handling method

Abstract

The invention provides a processing method for zero draining or low draining of electroplating wastewater. The method adopts an integrative technique, such as barrier concentration, barrier separation, ion exchange, and ultraviolet light catalytic oxidation, etc. The following steps are adopted: the pretreatment of the electroplating wastewater; the treatment for the three types of wastewater including pickling wastewater, wastewater containing cyanide and passivating and electroplating rinsing composite wastewater; and the treatment for the wastewater in an acid-soluble pool. Compared with the wastewater in an integrative electroplating plant with universal generic multi-plating species, only the prior water separation method with no need to control the troubled water strictly can realize : first, zero draining of the electroplating wastewater is performed; second, when operating in the low energy consumption way, 65 to 85 percent of water recovery is realized, the left wastewater which can not be recovered is discharged when reaching the primary discharge standard of National Standard; third, the processing cost is reduced; fourth, the metallic ion in the wastewater can be effectively recovered and utilized, at the same time, the benefit disinvestment cost is produced; fifth, the amount for causing solid waste is reduced; sixth, the invention is advantageous to realize the automatic control and the operation.

Description

technical field [0001] The invention relates to a treatment method for wastewater, in particular to a treatment method for electroplating wastewater. Background technique [0002] Electroplating wastewater treatment often uses chemical precipitation method, electrolysis method, common ion exchange method and other treatment methods in the treatment process. However, the above systems have certain limitations and cannot achieve zero emissions. [0003] The chemical precipitation method is now widely used in electroplating factories. In the production process, a large amount of acid and alkali needs to be added, as well as ferrous sulfate and polyaluminum chloride. As a result, the salinity rate of water discharge is increased, and the residual heavy metal ions in the water are still difficult to meet the discharge standard. Since the content of controlled substances specified in the waste water discharge standard is extremely low, excessive chemicals need to be invested to m...

AI Technical Summary

Problems solved by technology

Even if the existing equipment of each electroplating plant is fully utilized, most or all of the water cannot be reused, and the valuable metals such as copper, nickel, zinc, etc. mixed in the wastewater cannot be effectively separated and recovered.

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