Cities are crucial for building circular food systems. On 22 September 2024, the DCZ team was invited by Kedao Agriculture 科道农业—a company providing solutions for a circular economy—to visit their demonstration site and model community in Shuangliu District, Chengdu.
Since 2006, Kedao Agriculture has been developing circular solutions that combine agricultural production, sustainable living, and environmental protection on a demonstration site covering over 70 ha. The company produces organic rice, fruit, and vegetables. Toilet and kitchen waste from the neighboring community is converted into biogas for cooking and heating and into organic fertilizer for agricultural production. A special sewage system separates black and graywater in the residential buildings. Following treatment, graywater is used as a water resource in agricultural production while blackwater is used for biogas production.
The company has also constructed a multi-story residential building which integrates elements of vertical agriculture and rooftop gardening to produce food for residents. This work has been conducted in collaboration with the Chengdu Agricultural Science and Technology Center and the Institute of Urban Agriculture of the Chinese Academy of Agricultural Sciences.
In the basement of the building, tanks have been installed to raise fish for human consumption. The water from the tanks is recirculated into the vertical plant beds attached to the outside of the building, allowing the plants to absorb nutrients from fish waste in the water and cleaning the water before it is returned to the fish tanks.
“By integrating organic food production, sustainable living, and waste treatment, Kedao Agriculture has built a circular system that helps conserve water and land resources while reducing pollution and greenhouse gas emissions”, Kedao Agriculture assistant chairman Zeng Bin told the DCZ team during the visit.
The company has been awarded several patents for its technical solutions and is looking to expand its model both nationally and internationally.