Treatment and Reuse of Highly Concentrated Cutting Fluid Wastewater by Decompression-dehydration-drying System

FAN Yi1, ZOU Zhendong1, LI Ruili1, WU Xiaofang1, QIU Guoyu1,†, NAKAMURA Kazuhiko2, GAO Jian2

1. Shenzhen Engineering Laboratory for Water Desalination with Renewable Energy, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055; 2. Shenzhen DAIWA Environment Technology Co., Ltd, Shenzhen 518000; † Corresponding author, E-mail: qiugy@pkusz.edu.cn

Abstract A decompression-dehydration-drying system was designed and improved to deal with cutting fluid wastewater produced during metal processing. The results show that the removal rate of total suspended solids is more than 99.38%, and the average removal rates of N-HEX, BOD5, CODMN, total nitrogen, total phosphorus, copper and zinc are 99.07%, 96.67%, 98.64%, 81.28%, 99.33%, 98.69% and 99.79% respectively. Combined with ozone treatment it can further improve the removal rate of organic pollutants. Compared with other treatment methods, during the process of sewage treatment, the proposed system produces very little smell and noises, and do not need a large number of chemical agents, and has a small footprint and low cost. It is especially fit for the treatment of highly concentrated cutting fluid wastewater. Key words decompression-dehydration-drying system; cutting fluid wastewater; wastewater treatment; recycle