By Xinyi Li, EDITOR

Since the publication of the Implementation Plan of Chongqing Municipal Household Waste Classification System in November 2017, garbage classification has been comprehensively promoted at public institutions in its downtown, covering 680,000 households. By the end of this year, there will be 43 demonstration sub-districts and towns for household waste classification.

The pilot of the garbage classification to guide citizens

Since 2018, Chongqing Environmental & Sanitation Group Co., Ltd. (the Group for short) has assisted the placement of rubbish bins for the garbage classification and collection at the beginning. The Group developed the classified waste collection demonstration areas and extended the system to the front end of the work. It initiative helped Jiulongpo District to carry out garbage classification, now favoring 100,000 residents in two sub-districts and 30 housing estates.

At the pilot housing estate entrances and public squares, the Group has set up more than 900 garbage bins, making it convenient for residents to dispose of garbage as per classification. Meanwhile, it instructed residents to open the Green Account to gain points by correctly disposing of their waste. Such reward points can be used to exchange for some daily necessities at the designated places in the housing estates, or the intelligent network & logistics system for the transportation of classified wastes, to stimulate the citizens’ enthusiasm for waste sorting.

The scientific sanitation and data make the garbage classification more intelligent

The Group took the lead in constructing an intelligent network & logistics system for transporting classified waste in China to avoid mixed transportation of household wastes. It has invested 1.5 billion RMB in the construction of three garbage sorting logistics bases in Jieshi, Zouma, and Xiajiaba, based on the secondary transportation systems for garbage in the downtown. It has set up an intelligent multiple-stage sorting system for domestic wastes, which can discern types of garbage in a smart and high-precision method. Now it can classify garbage automatically and efficiently, with the total transfer volume of 9,600 tons per day.

The Group has set up a professional garbage classification system for dealing with four kinds of garbages: perishable, harmful, recyclable, and others. The appearances of such high technologies as the Internet+, big data, and cloud computing have promoted the traditional garbage sorting, transportation, and processing to develop quickly and intelligently, thus empowering the garbage recycling industry chain.

Create the whole industrial chain of garbage classification

In the perishable garbage treatment plant, the Group adopts the world’s leading technology of anaerobic digestion and cogeneration of heat and power. The separation of oil and water is conducted in the processing of perishable garbage. Meanwhile, the hogwash oil is esterified and undergoes interesterification to produce biodiesel, and then produces biogas through thermophilic anaerobic digestion. Biogas is used to generate electricity or create CNG upon being purified, thus converting perishable waste into usable energy.

Garbage classification creates wealth and value. For example, in the processing of kitchen waste using a high-temperature humid anaerobic process, 1-ton kitchen waste can produce 40kg biodiesel, 50 cubic meters CNG, and 150 kWh. With the low-temperature catalytic cracking process, 1 ton of waste plastic materials can produce 500kg regenerated fuel. The Group took the lead in using waste plastic bottles to produce chemical raw materials, in which 1-ton waste plastic bottles can produce 800 kg of chemical raw materials including PET chips.

One director of the Group said, “Since the inception, we always take the science and technology as the driving force and manage to integrate garbage classification, clearing and transporting, and treatment into the industrial chain featuring clear classification, a definite division of labor, and separated treatment processes.”

Source: Chongqing Daily News