Introduction of electroplating wastewater treatment and reuse equipment
 
       The electroplating industry is one of the three major polluting industries in the world today。
       According to statistics, the annual discharge of electroplating wastewater in the national electroplating industry is about 4 billion cubic meters, which is equivalent to the water supply of several large and medium-sized cities, seriously aggravating the shortage of water resources。The water consumption of electroplating and the serious pollution of electroplating rinsing water lead to the unsustainable development of electroplating industry。Now countries are competing to develop water reuse technology to solve the problem of water shortage and environmental pollution。Membrane technology is becoming a development trend to achieve these purposes。
 
        Because the membrane separation technology has the advantages of low energy consumption, no phase change, no pollution, and high separation efficiency and concentration ratio, the suitable membrane separation is used to concentrate the rinse water of electroplating solution, and the concentration ratio can reach 100 times (by volume).。The concentrated liquid after membrane separation is properly treated to reach a certain concentration of nickel ions and then returned to the electrolytic cell, that is, the nickel is recovered, and the permeating liquid of the membrane system, that is, pure water, can be directly returned to the bath of the plating part, so as to achieve zero discharge of electroplating wastewater treatment。Therefore, the application of membrane integration technology in the recycling of electroplating wastewater will not only cause secondary pollution, but also recover harmful heavy metals in the wastewater, turn the damage into treasure, and make the water resources be reused。
 
Second, electroplating wastewater reuse membrane electroplating wastewater zero discharge process
 
        Electroplating wastewater mainly consists of pretreatment acid-base washing wastewater and electroplating process rinsing wastewater, and the pollutants required by the acid-base wastewater group are washed oil, rust, acid-base, etc。After a simple physical and chemical treatment can be discharged or reused, but the physical and chemical treatment cost is high (mainly the cost of dosing), occupying a large area and other disadvantages。      
 
        As a new process for treating electroplating rinsing water, the membrane treatment process provides a "green" solution for the treatment of electroplating rinsing water. The wastewater from the rinsing tank is transported to the continuous membrane system through the pump for separation and concentration. The concentrated liquid enters the evaporator for further concentration or is configured with a new electroplating solution, and then returns to the electroplating tank。
 
        A filter is used for pretreatment before entering the membrane to remove possible particles to ensure the safety of the membrane system。The permeable liquid of the membrane separation system fully meets the deionized water standard and returns to the third rinsing tank for reuse。Therefore, the closed loop treatment system is realized, and in the whole circulation system, no other substances enter, and there is no material loss, and the material balance is achieved。
 
Third, the advantages of electroplating wastewater treatment and reuse membrane method

        1, waste water reuse, reduce the amount of rinsing water, can be further treated to achieve zero waste water discharge requirements, reduce the scale of biochemical, physical and chemical treatment, is conducive to enterprise expansion needs;     
        2, can recover useful metal ions, so that enterprises in the purpose of environmental protection while producing benefits;     
        3, the membrane effluent water quality is good, transparent, higher than the process water requirements of electroplating industry;    
        4, short investment payback period, small risk;     
        5, can be designed according to the processing requirements, and can continue to expand and increase the processing capacity and improve the processing through continuous optimization;     
        6, the system is easy to operate, occupy a small area。