Study On Treatment Of Electroplating Wastewater By Micro Electrolysis Technology

Electroplating is a technology which can decorate and protect products or give them new functions.But a large number of wastewater may be generated during the electroplating process.Since the composition of electroplating wastewater is very complex and there are high concentrations of heavy metal ions in it,it is very difficult to degrade organic matters using biochemical treatment.Therefore,electroplating wastewater should be treated by pretreatment technology.This paper is based on a research in wastewater of a plating industrial park in Shenzhen.It shows that in this park,the electroplating wastewater can be divided into synthetic wastewater,chromium-containing wastewater and cyanogen-containing wastewater.As the organic matters in this electroplating wastewater are almost biorefractory compounds,it couldn't be disposed by biochemical treatment even after coagulation and sedimentation by which heavy metals are removed.The micro electrolysis technology can transform the difficult degradation organic matter into the easily degradable organic matter,so it is necessary to use micro-electrolysis technology to pretreat the wastewater.Firstly,the optimum conditions of micro-electrolysis were determined by single-factor test and orthogonal test.The best residence time was 45 min.The best fit iron-carbon mass ratio was 1:1 and pH should be 2.5.Secondly,after the determination of several water quality indexes in wastewater before and after micro-electrolysis treatment,it was found that COD decreased and NH₃-N increased in the wastewater after micro-electrolysis treatment.This indicated that micro-electrolysis technology could make large molecular organics break chains,open loops and become readily small molecular organics.Finally,the mechanism and influencing factors of micro-electrolysis process were analyzed.Micro-electrolysis technology combines the principles of chemical kinetics and electrochemical kinetics.The process is very complicated and intermediate reactions and products are more.Therefore,SPSS and MATLAB were used to nonlinearly simulate the variation of micro-electrolysis treatment.The mathematical model of electroplating wastewater disposal using micro-electrolysis treatment was obtained and the model was analyzed by error analysis to determine the accuracy and validity of the model.