This project is located in the petrochemical industry base, Xuwei new district, Lianyungang city, Jiangsu province. The first phase is designed to 50000 m3/d scale. Wastewater plant effluent water quality is 1level of A.In this project,we provided bioprocess aeration control system(BACS) which is one of the two systems introduced into China earliest.BACS has a good running effect In many large sewage treatment plant and can completely meet the requirements of the project for the control effect and the stability.