Method for treating electroplating wastewater

Abstract

The invention discloses a method for treating electroplating wastewater. The method comprises the following steps: (1) primary physical-chemical treatment; (2) secondary physical-chemical treatment: after the discharged water generated in step (1) is subject to homogenizing treatment, adding sodium hypochlorite into the homogenized water, then adding sodium pyrosulfite into the obtained product to remove residual chlorine, and adding aluminum chlorhydroxide into the obtained product; and (3) biochemical system treatment: adding appropriate biochemical sewage into the product obtained in step (2), mixing the biochemical sewage and the product, then feeding the obtained mixture into a biological hydrolysis pool; controlling the mixture under appropriate conditions and within an appropriate retention time; carrying out reduction on the obtained mixture by utilizing facultative anaerobes; and hydrolyzing the obtained discharged water subjected to reduction, feeding the discharged water into an aerobic biological oxidation pond, and then carrying out mass propagation of engineering bacterias under an appropriate condition by using organic pollutants in wastewater. By using the method provided by the invention, the total treatment rates of a system are as follows: the treatment rate of heavy metal is greater than or equal to 99.7 percent, the treatment rate of ammonia nitrogen is greater than or equal to 90 percent, and the treatment rate of chemical oxygen demand (COD) is greater than or equal to 88 percent, therefore, the electroplating wastewater treated by using the method comprehensively meets the requirements of the Discharge Standard for Pollutants from Electroplating Industry (GB21900-2008).

Description

technical field [0001] The invention relates to a method for treating electroplating wastewater. Background technique [0002] With the rapid development of modern industry, the corresponding electroplating industry has also grown stronger. However, a large amount of toxic and harmful wastewater, waste gas and solid waste generated during the electroplating process pose a serious threat to human health and the living environment. How to reduce and control pollution in the electroplating industry has become an important problem that needs to be solved urgently. [0003] The treatment of heavy metal wastewater can be summarized into physical methods, chemical methods, physicochemical methods, biological methods, etc. Chemical and physical chemistry are widely used. Chemical method: various chemical reactions occur by adding chemicals, and finally form heavy metal precipitates to remove dissolved heavy metal ions. This process cannot effectively remove organic pollutants; phy...

AI Technical Summary

Problems solved by technology

[0007] The technical problem to be solved in the present invention is to develop a method for treating electroplating wastewater for the discharge water quality of electroplating enterprises to meet the "Electroplating Pollutant Discharge Standard (GB21900--2008)"