Treatment of wastewater containing chelated copper by electrolysis system

• Main Authors: Li, Wei-Lin, 李威霖
• Other Authors: Huang, Chih-pin
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/14856417688397175429

碩士 === 國立交通大學 === 工學院碩士在職專班永續環境科技組 === 99 === Effluent discharged from IC substrate manufactures contains high strength of the chelated copper. Once the factory discharge chelated copper into sewerage collection system, it may easily allow the copper concentration exceed the effluent limit. More than that, high strength chelated copper would damage the stability of bio-systems operation by causing the death of microorganism. The purposes of this research are to deal with wastewater containing chelated copper and retrieve copper as a valuable metal. The electrolysis-oxidization processes were applied in the study. The effluent sample discharged from the manufacturing process was also taken and used to investigate their treatability as well as the optimal conditions by a lab-scale of electrolysis system with the parameters of pH, electric current and the retention time. After that, the optimal parameters were applied to ensure the experimental feasibility as well as verify the applicability of electrolysis facility in the full plant. The results have revealed that the cupric ion removal efficiency decreases with increasing pH (pH2>pH3>pH4) after reaction for eight hours. Regarding to the effect of electric current, the result has showed that the cupric ion removal efficiency is proportional to electrical current (4A>3A>2A>1A). The highest removal efficiency of cupric ion is found to be 99% at pH2 and 4A, and the lowest is 83% at pH4 and 1A. The effects of pH and current density on COD removal were also evaluated. The COD removal increases with decreasing pH (pH2> pH3> pH4) and increases with current density (4A>3A>2A>1A). Therefore, the COD removal efficiency was approximately between 22% and 55%. The wastewater treated by electrolysis system was then flowed into the biological process. It was found that the COD removal maintained more than 50% with no biological inhibition in this system. Hence, this electrolysis/biological hybrid system can effectively reduce the concentration of copper and COD from the wastewater containing high strength chelated copper, and then lower the risk of effluent.