Tianhe district recently received an honor on the waste reduction front.

That's after the Basel Conventional Regional Center for Asia and the Pacific announced the first batch of recommended cases for the 2023 "Zero Waste City" program for pollution reduction, carbon reduction, and efficiency improvements.

A total of 36 cases in six major areas were selected nationwide, with Tianhe's application of "Green and Low-Carbon Integrated Technology for Low-Temperature Vacuum Dewatering and Drying at the Guangzhou Daguan Wastewater Treatment Plant" duly recognized.

It was the only case selected in Guangzhou, and the only one selected in Guangdong province in the area of construction waste and other solid waste.

The equipment gets to work at the Guangzhou Daguan Wastewater Treatment Plant. [Photo/Nanfang Plus]

The integrated technology for low-temperature vacuum dewatering and drying that the plant has introduced utilizes the principle of lowering the water boiling point by decreasing environmental pressure.

This can reduce the sludge moisture content from 97 percent to 30-40 percent in one step, maximizing sludge reduction.

The treated sludge can then be transported in fully enclosed vehicles to power plants, cement plants, and other disposal units for incineration, power generation, and utilization as building materials – facilitating harmless and resourceful sludge disposal.

Additionally, the plant has innovatively adopted water-source heat pump technology, tailoring the treated water from the plant as the heat source for sludge drying.

Statistics show that using this new technology can reduce carbon emissions by about 190 kilograms per metric ton of sludge, with a daily reduction of 31.2 tons of carbon emissions at design capacity.