The Bailonggang WWTP is recognized as the largest plant of its type in Asia. [See World’s 10 Largest WWTP]
This plant, located in Shanghai’s southern suburbs close to the estuary of the Yangtze River, began operating in 1999. In 2008 it was upgraded and expanded, and a further expansion in 2012 increased the plant’s capacity to 740 million gallons or 3.36 billion litres per day. The facility now processes more than half of the wastewater from Shanghai, China’s most populous city.
The Recent Plant Upgrades and Additions Included:
Eight Anaerobic Sludge Digesters and a Sludge Drying and Disposal Facility and Disposal Facility
Each of these eight new pre-stressed concrete sludge digesters has a maximum diameter of 25 metres, a height of 44 metres (32 metres above ground and 12 metres underground), and a volume of 12,400 m3.
Process Upgrade
The digestion process reduces the volume of raw sludge over a period of approximately 24 days, with the residual sludge then being dewatered and thermal dried. Approximately 44,500 m3 of biogas from the digestion process is generated each day and used to operate the sludge drying plant. The dried and deodorized residue is then disposed of, either to landfill or to non-crop applications.
Xypex to Enhance Durability (24,000 m2 treated with Xypex Concentrate)
After a comprehensive survey of many options, Xypex was selected by the construction project group to waterproof, protect and enhance the durability of these critical structures. All internal concrete faces of the eight digesters were treated with Xypex Concentrate. In areas where anaerobic activity and a highly aggressive chemical environment were anticipated, an acid-resistant lining was applied. However, the designers specified that Xypex also be applied to these specific areas as well, not only to provide secondary protection for the concrete but also to enhance the performance and durability of the primary acid-resistant lining.
The recent upgrades and expansion, costing $350 million, were engineered and constructed by the following group:
Beijing General Municipal Engineering Design & Research Institute
Shanghai General Municipal Engineering Design & Research Institute
Shanghai No. Seven Construction Co. Ltd.
Shanghai No. One Municipal Engineer Co Ltd.
China Nuclear Industry Huaxing Construction Co. Ltd.
Owner: Shanghai Municipal Sewerage Company
