Recruiting wastewater treatment engineers

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Description of the process flow at the wastewater treatment plant: Various types of wastewater are pre-treated in the workshops, after which they are pumped and transported to the corresponding adjustment tanks or collection tanks at the wastewater treatment plant. High-concentration synthetic wastewater is catalyzed with ozone and then mixed with high-concentration fermented wastewater; flocculants and coagulants are added to facilitate coagulation and sedimentation. The resulting wastewater, along with low-concentration wastewater that has settled naturally and domestic sewage, undergoes dissolved air flotation treatment before entering the homogenization tank. There, the wastewaters are mixed and homogenized; some of it is then pumped, with its temperature controlled by a heat exchanger, into the anaerobic reactor, while the rest goes directly to the subsequent A2O tank and secondary AO tank for further treatment. The effluent from the anaerobic reactor, along with the excess wastewater, enters the anaerobic section of the A2O tank. After precipitation, this effluent proceeds to the subsequent anoxic and aerobic tanks; the settled sludge can be returned to the anaerobic reactor or the inlet of the anaerobic section. The aerobic effluent, after precipitation, together with the excess wastewater, enters the secondary AO tanks. The nitrified liquids from each of these tanks, along with the returned sludge, are mixed and fed into the respective anoxic sections. The primary O section uses the suspended-sludge method, while the secondary O section employs the biofilm method. Under low organic load conditions, ammonia nitrogen is nitrified and COD is further removed, simultaneously enhancing denitrification. After precipitation in the secondary sedimentation tank, the effluent from the secondary AO tanks flows into an oxidation-coagulation sedimentation tank for further treatment, ensuring that all parameters meet the required discharge standards. The wastewater that meets the standards flows into the outlet tank; any excess flows into the Pasteur measurement tank, and after online monitoring, it is discharged into the park’s pipeline network. The sludge generated in each sedimentation tank, as well as the scum produced by air flotation, are pumped to the sludge thickening tank. After thickening, they are sent to a stack-type dehydrator. The dehydrated sludge is then conveyed via a screw conveyor into a sludge hopper, and from there it is pumped using a high-pressure screw pump to a sludge drying and granulation machine. The dried sludge is packed into ton bags for disposal elsewhere.