Modification and Application of a Combined Industrial and Domestic Wastewater Treatment Project

The technological modification of a wastewater treatment plant in Jiangsu Province was introduced. The original process designed to treat domestic wastewater only was modified to treat both industrial and domestic wastewater with the same treatment capacity, of which 60% was industrial wastewater. The modification measures included adding the pretreatment of air floatation, oil separation and hydrolysis acidification, changing the original A/O process to A²/O process, and expanding the valveless filter to include a Densadeg for advanced treatment. The results indicated that the modified process was suitable to treat mixed municipal wastewater due to the enhanced pretreatment and advanced treatment. The removal rates of COD, BOD₅, NH₃-N, TN, and TP reach 92.4%, 94.9%, 91.1%, 80.8% and 95.8%, respectively, and the effluent quality could meet the discharge requirements.