Urban surface water is fundamental to the survival of cities, providing not only a water source but also serving as a focal point for urban culture and social environments. In some cities, incomplete separation of rainwater and sewage results in combined sewer overflow (CSO) systems discharging mixed sewage and rainwater directly into water bodies during heavy rainfall, severely damaging the water environment and affecting urban water health. This is one of the main causes of surface water pollution in China and a contributing factor to the foul odor in urban rivers. Therefore, controlling sewage overflow pollution is crucial. In response to urban CSO overflow pollution, DWI focuses on pipeline detection and repair technology, research on detention tank processes, and municipal sewage emergency treatment processes and equipment. Among these efforts, an emergency sewage treatment device based on multi-effect clarification technology has been developed and introduced.

• Research on primary enhanced treatment processes

• Study on loading sedimentation carriers

• Research on efficient recovery processes of loading carriers

• Investigation of deep phosphorus removal and denitrification processes

Successful Case

>>> The Yining Combined Sewer Overflow (CSO) Emergency Treatment Project

Project Overview: The project involves the construction of approximately 3000 cubic meters of aeration storage tanks and three sets of highly efficient integrated rapid sewage purification and sludge dewatering systems. The system has a processing capacity of 10,000 to 15,000 tons per day, occupying only 1/15 of the land compared to conventional processes, with an investment cost of 1/10 of conventional processes. The overall pollutant removal rate exceeds 80%. With its short cycle, quick results, and low cost, it is one of the most cost-effective sewage treatment technologies available today.