A Tale of Two Rivers: Chongqing’s Largest Sewage Treatment Upgrading Project Put into Operation

By Xinyi Li, EDITOR

On June 3, according to Chongqing Drainage Company, Jiguanshi Sewage Treatment Plant upgrading project, the city’s most substantial sewage treatment work to improve effluent quality has been fully put into operation. With the service of the project, the effluent quality is superior to the national discharge standard of Class 1A.

With an investment of RMB 834 million, the project extended and upgraded a range of treatment facilities and processes in the past two years. Inside the plant, the sewage is physically treated in the coarse and fine screening cells and grit chambers to have the impurities filtered and settled and then chemically treated in the biochemical tanks where microorganisms decompose the organic matter. After that, the sewage is further precipitated to separate sludge from water and then treated with efficient precipitation and chlorination. As a result, the water discharged into the Yangtze River is very clear.

The sewage is treated by both physical and chemical ways to become clear

Jiguanshi Sewage Treatment Plant, with a daily capacity of 800,000 tons of domestic sewage, is the largest sewage treatment plant in Chongqing, which has the most complex sewer network system and the most extensive upgrading work. Meanwhile, it is the broadest cover for one-time deodorization in China, China’s first tail water power station, and the world’s largest sludge drying plant with the most advanced equipment and technologies. 

It can process 450 tons of sludge per day. The dried sludge can be used in landscaping, brick/pottery making, and cement manufacturing, significantly reducing the costs and environmental pollution risks arising from the transportation and utilization of untreated sludge, and genuinely achieving the reduction, and harmless recycling of sludge.

Jiguanshi Sewage Treatment Plant, with a daily capacity of 800,000 tons of domestic sewage, is the largest sewage treatment plant in Chongqing, which has the most complex sewer network system

The reclaimed water reuse system (treated water meeting the production/operation standards of the plant) with a capacity of 10,000t supplies water for chlorination, dosing, landscaping, production, and different uses, saving about 7,000-cubic-meter running water (worth over RMB 30,000) per day. Relying on the 16-meter head, the plant has also constructed a tail water power station, which can generate 8 million kWh of electricity annually, accounting for 15% to 17% of the total consumption and saving nearly RMB 5 million per year.

Jiguanshi Sewage Treatment Plant has formed a circular economic chain integrating sewage collection, sewage treatment, sludge treatment, reclaimed water reuse, and tailwater power generation. In the future, the plant will continue to improve its development model and promote the progress of environmental protection in the Yangtze River Basin and the industry.

Related link:

Overall Improvement in Water Quality As a Result of Urban Sewage Treatment in Chongqing

Source: Chongqing Daily News