The Beijing city government first set out to promote garbage sorting in 2009. Authorities have since called on residents to sort their household waste into four types-recyclable waste, kitchen trash, hazardous waste and others-and leave it in a corresponding dustbin or trash can.

Blue-colored dustbins signify items within are recyclable, green represents kitchen trash, red corresponds to hazardous materials and grey to other waste.

To promote the awareness of garbage sorting and expand the base of participants, authorities have employed workers to help residents on the spot. With intelligent devices, those who throw in recyclable waste at given sites will be rewarded with bonus points, which can be redeemed for daily goods.

At some residential communities, there are no color-coded dustbins. Instead, a scheduled garbage collection service is offered to help improve the environment. In other communities, workers offer a door-to-door service to collect recyclables or kitchen waste.

Using intelligent devices and facilities, which feature finger and face recognition technology, is a new trend in the sector, industrial observers said.

Beijing Environmental Sanitation Engineering Group has been promoting new garbage sorting facilities such as recycling cabinets and smart kitchen waste trash cans since 2016, Xinhua News Agency reported.

Nearly 26,000 metric tons of household waste is generated across Beijing on a daily basis and 29 terminal garbage disposal facilities are working at full capacity, Sun said.

Vice-Mayor Zhang Jiaming told the Standing Committee of the Beijing People's Congress at a meeting in May that nearly 9.3 million tons of household waste was processed in the city last year.

The second phase of incineration plants on the outskirts of Beijing, such as Miyun and Shunyi districts are being adjusted.

In addition, builders are advancing the construction of a comprehensive treatment center in Fangshan district and a construction waste recycling project in Haidian district. Their main structures are scheduled to be completed at the end of this year, The Beijing News reported.

Wang Weiping, deputy chief engineer at the Beijing Commission of Urban Management, told news portal Economic View that garbage sorting is conducive to processing and reclamation and also helps to improve residents' environmental literacy.

To date, the city government has designated 100 model residential communities and townships for garbage sorting, accounting for 30 percent of the city's total.

By the end of this year, the number is expected to increase to more than 200, or 60 percent, Sun said, adding that the coverage is planned to expand to 90 percent of the city's total area by 2020.