China to achieve green and low-carbon transformation with 'waste-free city' construction

Six years on, China has made great strides with "waste-free city" projects and plans to build more than 3,700 of these, with an investment of more than 1 trillion yuan (over $140 billion), during the 14th Five-Year Plan period (2021–2025), according to China's Ministry of Ecology and Environment.

In 2019, 11 cities and five areas were selected to pilot waste-free projects, which emphasizes reducing solid trash production at the source and increasing recycling. So far, 113 cities and eight areas are in the process of building cities with no waste.

Proper disposal of kitchen waste is one of the tasks to achieve zero waste in Zhuhai City, south China's Guangdong Province. A construction of a kitchen waste treatment project was completed in early 2024 in Zhuhai Fushan Industrial Park. This type of project can process 500 tonnes of kitchen waste each day, with 8.25 tonnes of crude oil extracted, generating about 29,000 kilowatt hours of green electricity, which can be used for about 2,900 households.

Another method which was used to deal with kitchen waste in Xinchang County, east China's Zhejiang Province is biodegradation – the process where microorganisms break down organic matter. Here, waste is separated into liquid and solid. The liquid will be used in industries after purification, while the solid will be shredded and used to feed the larvae of hermetia illucens, commonly known as black soldier fly. Eventually, 60 percent of the solid waste is converted into adult insects that can be sold to local fish farmers and the rest of the waste is converted into organic manure.

"According to the daily processing capacity of about 100 tonnes and the annual processing capacity of 38,000 tonnes, nearly 18 million yuan (over $2.5 million) is generated through this method," said Chen Kefeng, director of the county's construction bureau.

How can construction waste resources be better utilized? In southwest China's Chongqing Municipality, useless building materials were made into bricks for sidewalks, which is both environmentally friendly and economical.

With government agencies, enterprises and schools as targets, more than 25,000 production and living units have been built to practice the "waste-free city" concept, gradually forming a green and low-carbon lifestyle, from schools to families and society.

It is expected that the proportion of "waste-free cities" will reach 60 percent by 2027 in China.