I. Overview The program intends to use the conventional "A / 0 biological contact oxidation" process, the treatment process is relatively simple, easy operation, low daily cost, water stability, the main equipment using high-quality steel box, taking into account the living area The surrounding environment and health problems, so the domestic sewage treatment project decided to use all-buried structure, the upper casing, can be planted flowers and plants, lawn, improve the landscaping. Second, the quality of incoming and outgoing water Standard sewage influent quality No. Project Water 1 COD 300 (mg / l) 2 BOD 150 (mg / l) 3 SS 200 (mg / l) 4 Ammonia 40 -9 6 Animal and vegetable oils 20 ~ 30 (mg / l) Design effluent quality No. Item effluent 1 COD ≤100 (mg / l) 2 SOD ≤20 (mg / l)) 3 SS ≤70 (mg / l) ≤ 15 (mg / l) 5 PH value 6-9 6 Animal and vegetable oils ≤20 (mg / l) Third, the process flow Fourth, the sludge treatment instructions Sludge treatment is usually small sewage treatment station there are two ways to sludge Concentrated mechanical dehydration, and second, sludge drying treatment. Consider sludge concentration mechanical dehydration owners invest large, and sludge concentration and drying of the surrounding health impact. Due to the sludge digestion system provided in the process, the amount of sludge produced is extremely small. Therefore, after comprehensive consideration, the sludge produced in this project is only subjected to simple concentration treatment and then manually cleaned and operated outside for manure every year. Fifth, a brief description of the treatment process facilities Grille Well (concrete) grille wells set in the regulation of the pond water into the water through the end of the design considerations of land conservation and investment. Grille wells set up artificial grille, intercept through the artificial grille in addition to larger domestic sewage suspended solids, such as solid and paper dust, water pump protection and follow-up pipeline system is not blocked, and in the grille wells set cover, Antifreeze play a role. Regulating tank The sewage treatment tank is set up throughout the treatment system. By adjusting the pool setting, the water quality and water quantity can be fully balanced so that the sewage can enter the subsequent treatment unit more evenly, improve the impact resistance of the whole system, reduce the design scale of the treatment unit, and reduce the impact of operation cost and water quality fluctuations . In the regulation of the pool set air mixing device to prevent precipitation phenomenon, at the same time can play a role in the balance of water quality. Set the level of automatic control device, the pump will automatically open according to the level. Due to the high organic content of sewage, BOD5 / CODcr = 05 has good biodegradability in hypoxia tank, so biofilm is designed. Because of the high content of organic ammonia in domestic sewage, it will appear in the form of ammonia ammonia during biodegradation. Therefore, the indicator of cyanamide in row eight water will be increased, and oxygen ammonia is also a pollution control indicator. Therefore, before contacting the oxidation tank Plus anaerobic tank, the anaerobic tank can use the nitrate mixed in the refluxing mixture and the organic carbon source in the influent to carry out denitrification, so that N02 and N03- in the influent can be reduced to N2 to achieve deamination, Organic oxygen while degrading the value of ammonia. Contact Oxidation Sewage by the anaerobic tank treatment, gravity flow into the contact oxidation tank, thus entering the contact oxidation stage, that is, into the aerobic treatment. Contact oxidation pond is a kind of biofilm-based biological treatment device with both active sludge. By providing oxygen source, the organic matter in sewage is absorbed and degraded by microorganisms, so that the water quality is purified. In the design process to consider the contact oxidation time is appropriate, the internal high surface area of ​​elastic filler, filling rate of 70%, the specific surface area of ​​nearly 600m2 / m3, the design area load should also take full account of the surrounding environment, to ensure better Processing efficiency. Therefore, the design load should choose a lower value of 0.83kg / m3 day. Air-water ratio also consider the higher value of 15: 1, the aeration form of micro-aeration, aeration head to consider the current international water treatment more advanced film Ai head. The device will never appear clogged during operation, has the advantages of small aeration pores and high utilization of oxygen, and has unparalleled advantages compared with traditional aeration forms. Contact oxidation is a biofilm-based biological activated sludge process. After fully oxygenated sewage, immerse all the filler and aim at the speed of flow through the filler, filled with biofilm fill surface after full contact with the oxygenated sewage, so that the organic matter in the water is adsorbed and degraded, so that the sewage is purified. The design uses the international advanced three-dimensional elastic filler, not only the surface area, and superior water flow characteristics. As a large number of microorganisms are fixed on the surface of the packing layer, forming a high concentration of sludge bed, commonly known as biofilm, which has a strong resistance to load impact. This structure because there is no or very small amount of suspended activated sludge, solid and will not produce sludge expansion, which is the major feature of this method. The key to this phase of production lies in the bio-culture and bed-fall of the packing layer, so long as this work is done in the initial stage of operation, there is little need to ask other questions during operation. Sedimentation tank sewage through contact oxidation, the entrained oxidation process produces a small amount of activated sludge and metabolic biofilm, and can not be biodegraded a small amount of solids into the second settling tank for solid-liquid separation, the water was clarified discharge . Sedimentation tank using vertical flow, sedimentation of sludge all back to the sludge tank for further digestion to reduce excess sludge. Out of the tank designed to adjust the level of tooth-shaped water collection tank to increase the precipitation effect. Disinfection tank according to national standards "TJ14-74" production, effective disinfection stay for 40 minutes or more. Escherichia coli and other bacteria in this unit to get the most effective kill, then the number of bacteria in the water effluent sedimentation biological dew sink sludge regularly discharged into the sludge tank for anaerobic digestion, while using the gap aerobic mixing Method, through the digestion can reduce the remaining sludge volume of about 70%. "Sludge supernatant liquid activated sludge carried back to the anaerobic, the remaining sludge regular clean-up (usually removed twice a year). Regulation pool, hypoxia , Aerobic and secondary sedimentation tank and other gas production by the ABS pipe row ^ high altitude downfall, so as to avoid secondary pollution. VI Conclusion Domestic sewage treatment by the entire set of equipment that can discharge or discharge into the municipal pipe network.