Engineering Design of a Township Sewage Treatment Plant in Eastern China

Abstract

A township in eastern China needs to build a new sewage treatment facility because the existing sewage treatment plant cannot meet the demand for predicted sewage volume. The scale of the new sewage treatment project is 14,000m³/d, and the effluent quality of the project shall be implemented in accordance with the discharge limit of the main pollutants of the new urban sewage treatment plant in the local standard of Zhejiang Province in the "Pollutant Discharge Standard for Urban Sewage Treatment Plants (DB33/2169-2018)". The process adopts the modified A²/O biochemical process as the core of secondary treatment to strengthen nitrogen and phosphorus removal. Magnetic coagulation and precipitation filtration are selected for deep treatment to ensure that SS and TP meet the standards; Sodium hypochlorite is used for disinfection, snail dehydrator is used for sludge treatment, and biological soil method is used for deodorization. The factory area has reasonable layout, clear functions, and smooth water flow. The total investment of the project is about 110 million yuan, and the effluent will meet the standard stably after it is put into operation in 2025, effectively improving the regional water environment and providing a demonstration for the expansion of similar township sewage plants.