Design On Upgrade Of Process Project Of The Wastewater Treatment Plant In Municipal Development Zone

As China continues to accelerate the pace of urbanization, urban sewage emissions growth year after year, the existing sewage treatment capacity has been unable to meet, resulting in non-compliance of sewage discharged directly leading to the city drinking water source is contaminated, which became the city manager eager to solve issue. Improve sewage treatment capacity, realize the recycling of wastewater, is to solve the water environmental pollution, ease the shortage of water resources of the most effective ways. The discharge standard for wastewater treatment plant in China also in unceasing enhancement, the execution is the urban sewage treatment plant pollutant discharge standard "(GB18918-2002). Wastewater regeneration of implementing the urban sewage recycling water quality standard of urban water mixed (GB/T18920-2002).The sewage treatment plant of municipal was built in 1988, the sewage treatment process using anaerobic/aerobic activated sludge process, the design of effluent is executed when the secondary emission standards. In July 1,2008, the liaoning province introduced new local standards "integrated wastewater discharge standard" (DB21/1627-2008), the sewage treatment plant effluent water quality to meet the requirements of the level of A standard must be upgrading of wastewater treatment process. The topic is mainly aimed at the sewage treatment plant of wastewater treatment process, combined with the water quality, upgrade technology for sewage treatment project to carry out the research, purpose is through technical and economic comparison, identify the upgrading technology of sewage treatment plant wastewater treatment, parameters optimization design technology at the same time, to complete the process design.The design of the sewage treatment plant upgrading project scale invariant, is 80000 m3/d. According to water quality monitor data in nearly three years, design the water quality was confirmed as the following:SS=210 mg/L, BOD5=230 mg/L, CODcr=550 mg/L, TP=6.5 mg/L,TN=60 mg/L. The design effluent is executed "urban sewage treatment plant pollutant discharge standard" level A emission standards:SS?10mg/L,BOD5?10mg/L,CODcr?50mg/L, TN?15mg/L, NH3-N?5(8)mg/L,TP?0.5mg/L,Fecal coliform ?103 pcs/L.According to the requirements of water quality and water quality, combined with the existing sewage treatment technique, through the comparison of two sets of technical scheme, determine the biological treatment system used in sewage treatment upgrade process has the function of phosphorus removal, nitrification and denitrification denitrification function completely improved A2/O biological nitrogen removal process. The concrete retrofit scheme is: The modified A2/O biological nitrogen and phosphorus removal processes. Removal of the original four primary settling tank and four bio-pool, newly built four in place improved A2/O biological pool, a fine grid between the new and aerated grit chamber, an increase of carbon between an upgrade pumping stations and regulators with wells, a water room and an inter-dosing.The sewage treatment use high-density sedimentation tanks+?-filter treatment process+ ultraviolet disinfection process.Design parameters of various structures to deal with theoptimization, design and calculation are performed; alsothe investment cost of the technological transformationprojects are analyzed.The process scheme can make the effluent quality meet the national effluent standard, with improved A2/O+high density sedimentation tank of +V type filter and UV disinfection.