As of August 15, Haerwusu Sewage Treatment Station of CHN Energy Zhunneng Group cumulatively treated a total of 4.272 million tons of sewage since its operation in 2008, and reuse rate of reclaimed water reached 100%. All waste water has been entirely used for road dust reduction, reclamation and greening in Haerwusu Mining Area, as well as production of coal preparation plant. Sewage reuse has really come true.
500 tons of domestic sewage flow out from Haerwusu Mining Area every day. How is the sewage treated?
Haerwusu Sewage Treatment Station looks like a small park, dotted with green trees and covered by luxuriant grass. In addition, there is a small vegetable patch, where long beans and cucumbers are planted. How refreshing and comfortable it is! Unexpectedly, this is a place where sewage is properly treated.
“At present, technique of Membrane Bio-Reactor (MBR) is applied for sewage treatment in Haerwusu Sewage Treatment Station. This new type of water treatment technology blends activated sludge method and membrane separation technology.” Liu Naixiang, the leader of comprehensive squad of Haerwusu Mining Area Plumbing Team, introduces as follows: “In our mining area, domestic sewage flows to the collection tank of the sewage station through the drainage pipeline, and at first enters the grilles to filter out the debris with diameter of larger than 5 mm. Then domestic sewage enters the regulating tank. Sewage pump is used to send the sewage to the vertical flow sedimentation tank for sedimentation. Sedimented sludge enters the sludge mixing tank through the sludge discharge pipeline. The sewage is discharged to the intermediate tank.”
In the outlet pump room, Wu Chunxia, a member from assay test team of Haerwusu Mining Area Plumbing Team, extracts the treated sewage on the spot, pours it into the measuring cup, and compares it with the water sample before purification. It can be clearly seen that the originally dark sewage has turned limpid and clear. According to Wu Chunxia, “11 assay test items should be conducted for such water, and it will only be sent to the water distribution plant after all the indicators are up to standard.”
Haerwusu Sewage Treatment Station is dedicated to treatment of domestic sewage and industrial sewage in the open-pit coal mine, coal preparation plant, equipment maintenance center, plumbing team, material supply station, Nanping Station of Xinshuo Railway and locomotive turnaround depot of Haerwusu Mining Area. It can treat 800 tons of sewage water on a daily basis, and achieve the annual reclaimed water output of 230,000 tons.