First appeared in
Asian Development Bank
50 climate solutions from cities in the People's Republic of China
Shanghai is addressing the problem of sludge with maximizing the circular economy, maximizing financial value, and
minimizing environmental damage.
Shanghai is addressing the problem of sludge with maximizing the circular economy, maximizing financial value, and
minimizing environmental damage.In the western suburbs of Shanghai, Qingpu District is embracing the circular economy to turn sludge into renewable energy and building materials. Under a build-operate-transfer agreement, the Qingpu Sludge Drying Plant has been constructed, with the capacity to process 200 tons of sludge every day. While sludge would normally be dumped into landfill, with negative polluting impacts, this project dries the sludge to produce a product that can be burned in a power station to generate electricity.
12K
TONS OF CO2 ABATEMENT IN THE FIRST YEAR OF OPERATION.
Creating value from every stage of the process is crucial. Excess heat from the drying process is recycled in the nearby power plant and, after the dried sludge has been burned to generate power, the ash by-product is sold as a building material for use in cement and bricks. Abating 4,600 tons of coal consumption, the project avoids 11,500 tons of CO2 emissions each year, which add to the avoided emissions of not placing the sludge in landfi ll. The project is part of the national water eco-civilization initiative demonstration program, which aims at sharing knowledge with others.
Proper management of sludge in Shanghai is improving the local environment and providing a circular economy solution to a growing problem (photo by Lie Wu).
The Challenge
Sludge, a by-product of wastewater treatment, is a signifi cant and growing problem in the PRC, causing serious water pollution and emitting 11 million tons of carbon each year. Reusing the sludge for energy production and building materials will turn it into an asset.
Co-Benefits
Economic By fully embracing the circular economy, much greater value can be gained from the sludge, estimated to be CNY2.3 million per annum.
Environment Better sludge management prevents the release of methane to the environment and more coal being burned for energy generation, as well as reducing heavy metal pollution.
Health Through improved processing of sludge, water quality and odors are controlled, safeguarding the local population’s health.