Composting provides a sustainable solution to the biosolids issues in Shenyang, China

Shenyang Biosolids Composting Plant is a one-of-a-kind facility that is designed to handle and treat up to 1,000 tonnes of 80% moisture content wet biosolids per day from four municipal wastewater treatment plants (WWTPs) that have a combined capacity of 1,600 MLD in Shenyang City, Liaoning Province, China. The composting plant covers an area of approximately 130,000 m². The moisture content of biosolids will be reduced to 35% by biodrying. The main facilities in the plant include the materials handling and mixing system (for wet sludge, raw material and compost), the agitated composting bed system, the ventilation and odor control system, the truck scale unit, the storerooms (for raw material and product), and the other auxiliary facilities. The design has incorporated the necessary environmental considerations for the protection of workers’ health and safety as well as the potential impacts on the neighboring communities. The finished compost product will be sold as soil amendment and/or auxiliary fuel. In comparison with other technologies, this plant is favored for the low capital cost (0.279 million RMB per wet tonne of sludge), the low operating cost (173.13 RMB per wet tonne sludge) and the low energy consumption/carbon footprint. The plant is currently under construction. The installation works of No.3 composting train is scheduled to be carried out in June 2012. When the plant is commissioned in September 2012, it will become a sustainable solution to the sludge problem in Shenyang City.