This paper mainly adopts A2/O technology, advanced sewage thick grille, followed by a lift pump the water into the fine grid, then the sewage enters the settling basin, removing relatively large sand water, after the water directly into the primary settling tank, a primary sedimentation tank to remove part of the SS, skimming floating treatment and, on the other hand through the primary settling tank can stabilize the quality and improve the quality of volatile fatty acid in water。 Enter from the tank after the raw water to the anaerobic tank, anaerobic tank is the role of biological selector, is conducive to the expansion of inhibiting filamentous bacteria, activated sludge settling property was improved, the original water flow to the anoxic tank, nitrate denitrification bacteria will be transformed into nitrogen flow into the last row into the atmosphere by biological denitrification role so to achieve the purpose of nitrogen removal, denitrifying bacteria due to nitrification of ammonia and ammonia will be converted into organic nitrogen into nitrate ammonification。 In the end, the mixed liquid flowing from the aerobic pool is returned to the anoxic tank, and the nitrogen and phosphorus removal is carried out synchronously。 The remaining effluent then flows into the two clarifier, where the mud and water are separated in the two clarifier, the mixture becomes clarified, and the remaining sludge is returned to the anaerobic tank。 Finally, the treated remaining water enters the disinfection contact pool。 After separation, the sludge enters the sludge concentration tank and is compressed and transported out of the tank。 A2/O process is the use of design is simple, the total hydraulic retention time is less than other similar technology, saves the investment in infrastructure, and in the process of anaerobic, anoxic and aerobic conditions under the alternate operation, is conducive to the expansion of inhibition of filamentous bacteria, sludge settling property was improved, and the process without the need for external carbon source。 Anaerobic tank need only slow agitation, running cost saving。

Through the design of the sewage treatment plant covers an area of 53204m2, there are 2 specific coarse grid and 1 sewage lifting pump, 2 seat, 2 seat fine grid aerated grit chamber, 2 primary settling tank, aeration tank, 2 4 2 two sedimentation tanks, sludge storage tanks, 2 seat contact disinfection tank, the 1 seat, 1 seat sludge dewatering room drum fan room。 The waste water is cut off by the total drainage pipe in the West and is discharged into the river after being treated。 The sewage treatment plant is rectangular。 Restaurant, office and other auxiliary building plant located in the southern area, large sewage treatment plant structures in the north, east along the west line process, sludge treatment system in southwest wastewater treatment plant。 The main road of the plant is 10 meters wide, and the distance between the two sides of the building is not less than 20 meters。 The secondary road is 8 meters wide, and the distance between the two sides of the building is not less than 15 meters。 The layout features of the plant are as follows: the flow line is clear and the layout is compact。 The location of the blower room and the reflux sludge pump station is close to that of the aeration tank and the two sedimentation tank, which saves the cost of piping and power and facilitates operation and management。 The office, the living house and the processing structure, the blower room and the pump house are kept at a certain distance, which is located in the upper wind direction of the perennial main wind direction, and the sanitary conditions and working conditions are better。 The total investment cost is 133 million 364 thousand and 660 yuan, and the unit water control cost is 0。57 yuan / cubic meter。 The design is economical and feasible。

目  录

1 绪论 1

1。1 设计任务及原始资料