Advance Treatment Of Pesticide Wastewater By Electrodialysis

Our country is agricultural country, the quantity of pesticide production wastewater is large. It is not only difficult to treat, but also has the residual of salt and toxicity organic compounds. Advanced treatment is an effective way to solve the problem of environmental pollution and water shortages. Electrodialysis as one of the membrane separation technology has the advantages of simple operation, without addition agents and low energy consumption, etc. But there are membrane fouling and can’t effectively remove organics disadvantages in the application.In this paper, we use the self-made electrodialysis reactor to depth treat the pesticide wastewater to analyze the effect of salt and organics removal. The influence of membrane organic pollution for salt removal has been done with the simulated wastewater. Then we were coupling the electrodialysis with electrochemical oxidation technology to improve the deficiency of traditional electrodialysis that can’t effective removal organics and the low desalination rate.It is show that the removal rate of salt and TOC is reach to95.8%and72.3%by the four-compartment electrolytic cell for pesticide tail water advance treatment, effluent is good, but the problems is membrane fouling, which lead to a longer operation time and the rise of effluent TOC, but the flux can has a recover by chemical cleaning at certain extent. It is found that in the electrodialysis process can effectively separate charged organic small molecular weight, but for the characteristics of pollutants such as tricyclazole can’t, in spite of it was charged. Under the electric field the ion exchange membrane would be polluted because of the removal of charged organics. Through the experiment discovered that the voltage can affect the pollution of ion exchange membrane and desalting efficiency as the BSA Simulated wastewater with salt. The anion-exchange membrane pollution is more serious than cation-exchange membrane.Coupling electrodialysis with electrochemical oxidation technology, and compare it to traditional electrodialysis reactor with the simulated wastewater contain Na2SO4and tricyclazole as dilute stream. The effluent conductivity of electro-electrodialysis and traditional electrodialysis respectively are0.229ms/cm and0.489ms/cm,0.278ms/cm and0.549ms/cm,0.693ms/cm and1.714ms/cm under the different Na2SO4concentration of1g/L5g/L and10g/L. It is show that electro-electrodialysis has the advantages of higher desalination rate, lower power consumption and an effective degradation of organic matter compare with traditional electrodialysis. At the same time, the parameters of voltage, inflow concentration of salt and organic compounds have a significant impact on operation effect.