Chongqing Heishizi Restaurant Waste Treatment Project (phase 1-4)

Project Overview:
Raw Materials and Scale: 1000 tons/day of restaurant waste 
Biogas Production: 80000 m³/ d
Application of Biogas: Power Generation in phase 1-3, Purification of BNG in phase 4
Production Time: 2013

The Heishizi Restaurant Waste Treatment Plant is designed to treat 1000 tons of restaurant waste per day (in four phases). The first phase is completed and put into use in 2011. It is mainly responsible for the harmless treatment and resource utilization of restaurant waste in the main urban area of Chongqing.

The Chongqing restaurant project is the first in the country to carry out the practical application of the "mixed anaerobic digestion" process technology for organic waste such as restaurant waste, sludge, fruits and vegetables. The project has introduced the world's leading "high-temperature anaerobic digestion, cogeneration" process technology. This process involves separating restaurant waste into oil and water, producing biodiesel through esterification and ester exchange of wastewater oil. It produces biogas through high-temperature anaerobic digestion of wastewater. The biogas is purified and used for power generation or CNG production. Based on the daily processing of 1000 tons of restaurant waste, it can generate 28 million cubic meters of biogas, generate 33 million kilowatt hours of electricity, produce 8000 tons of biodiesel, produce 7.98 million cubic meters of CNG, and reduce carbon dioxide emissions by 220000 tons annually. It can achieve the resource utilization of turning restaurant waste into treasure.

Purac won the first prize of Chongqing Science and Technology Progress Award for this project. Five ministries including the National Development and Reform Commission, the Ministry of Construction, and the Ministry of Environmental Protection have included the treatment of restaurant waste in Chongqing as a national demonstration project. CCTV and Xinhua News Agency have carried out publicity and reporting.

In China, the Chongqing Restaurant Waste Treatment Project is the first industrial project to treat large-scale restaurant waste. Since 2009, the core process systems used in the Chongqing Restaurant Waste Treatment Project, such as sorting and pulping system, high-temperature anaerobic system, and continuous oil recovery system, have been operating well. In 2018, with the increasing demand for restaurant waste and municipal sludge treatment in some districts of Chongqing, Chongqing Environmental Sanitation Group built the Luoqi restaurant waste and sludge collaborative Anaerobic Project. Purac provided a complete set of process design and core equipment for high-temperature anaerobic and sludge thermal hydrolysis.