As one of the most developed cities in China, Shenzhen boasts 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 every day. 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 solution to apply centralized treatment of the sludge in large quantity in the minimizing, defusing, and recycling manner, so as to prevent secondary pollution caused by sludge.
With SUEZ's proprietary Thermylis® and its two-stage waste heat recovery process, i.e. the waste heat of tail gas upon incineration is used respectively to preheat air and produce steam, to realize direct sludge incineration upon preliminary drying in the high-temperature air condition, thus reducing the auxiliary energy consumption to the maximum extent. The project employs the combination of dry process of dust removal and wet process of acid removal for tail gas purification, so as to meet the stringent emission standards.
After incineration, the sludge is most thoroughly reduced, stabilized and defused, while featured with environment-friendliness. 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.