A pioneer project of wastewater reuse in China

A wastewater reclamation project involving a pilot-plant study and further design and construction of a full scale advanced wastewater treatment plant is presented in this paper. A wastewater with a flow of 8000–10,000 m3/d comprising 40% industrial wastewater from a machinery factory and 60% domestic wastewater from residential area with a population of about 50,000 people is treated, and 50% of the treated effluent is directly reused for washing, boiler supply, air pollution control, cooling, washroom flushing, landscape irrigation, and construction. The severe shortage of water in this area and the pollution caused to the river leading to the Zhangze Reservoir necessitated this project. The pilot-plant study was conducted to provide sound technical information for the final construction of a full-scale advanced wastewater treatment plant. The wastewater treatment plant [with a capital cost of 3.92 million yuans (1 YUAN = 0.27 U.S. $)] which employs a two-stage attached growth biological treatment process followed by sand filtration and disinfection has been put into operation successfully. The planned removal efficiencies of COD, turbidity, and total coliforms are achieved by this plant. Economic efficiency analysis conducted shows that the net gain of the project is 248,000 yuans annually.