Shenzhen Shangyang: coping with first-tier city challenges in China
Shenzhen is the first special economic zone established upon China's reform and opening-up, and is now one of the four first-tier cities in China. SUEZ has built its first large-scale sludge centralised treatment project for the city.
Centralised treatment of municipal sludge
As one of the most developed cities in China, Shenzhen boasts a prosperous industry and commerce, and is densely populated. Its resident population reached more than 11 million in 2016, thus giving rise to a large quantity of domestic and industrial wastewater everyday. Therefore, Shenzhen has built many large-scale WWTPs to keep the city clean and to protect the environment. However, sludge, as a byproduct of WWTP, is another issue to take care of. Shenzhen must find an economic and effective treatment solution for sludge in large quantity, in the most sustainable manner to prevent secondary pollution issues.
The first centralised sludge treatment project in Shenzhen
The first sludge centralised treatment plant of Shenzhen, built by SUEZ, was the group's first sludge plant that applied its Thermylis®2S high temperature fluidised bed incineration process in China. It is used for treating the dewatered sludge from more than 10 municipal WWTPs in the central area of Shenzhen and Longgang District.
Thermylis®2S high temperature fluidised bed incineration process
With SUEZ's Thermylis®2S high temperature fluidised bed incineration process and its two-stage waste heat recovery process, i.e., the recovered waste heat upon tail gas incineration is used respectively to preheat air and produce steam to accomplished the preliminary drying of sludge in high-temperatured air condition, thus reducing the consumption of auxiliary energy to the maximum extent. The project employs the combination of the dry process of dust removal, and wet process of acid removal for tail gas purification, to meet the stringent emission standards.
After incineration, the sludge is thoroughly reduced, stablised and defused, and is eco-friendly. This can be used as a reference for solving the dilemma with large-scale urban sludge treatment.
Shenzhen Shangyang Sludge Project has a treatment capacity of 800 tons wet sludge per day, it is the largest sludge treatment facility in Shenzhen.