Wastewater Treatment Process Of Tianjin Shuang Qing Wastewater Treatment Plant

The influent of Wastewater Treatment Plant in Tianjin Shuangqing is mixed withresidential wastewater and pharmaceutical wastewater. The engineering requires thatthe effluent quality reaches the level A, which puts forward higher requirements onnitrogen and phosphorus removal. It is shown that residential wastewater containshigh ammonia nitrogen and total nitrogen content and enough carbon sources by theanalysis of water quality characteristics. However, pharmaceutical wastewater existscarbon sources shortage, which means extra carbon source is necessary. Sub-qualitytreatment and centralized treatment are presented in this engineering. Finally, weselect the method of collecting and pretreating water by sub-quality after comparisonof scheme. Thus, we could take advantage of the carbon source in residentialwastewater to make up for the shortage in pharmaceutical wastewater. Residentialwastewater is pretreated by the process of coarse and fine grid&aerated gritchamber, while pharmaceutical wastewater is pretreated by that of coarse and finegrid&aerated grit tank&water regulating pond&hydrolysis acidification pool.It is found that the wastewater is easy to biolization after water quality prediction. Asa result, the main process of this wastewater treatment plant is selected as biochemicalmethod. At present, there are several commonly used treatment of nitrogen andphosphorus removal，such as AAO method, oxidation ditch, SBR and so on.Improved AAO with reflux sludge denitrification section could solve thecontradiction between removal of nitrogen and phosphorus, assuring the effect ofnitrogen and phosphorus removal and making full use of carbon source at the sametime. Due to its stable operating, mature technology and rich management experience,Improved AAO with reflux sludge denitrification section&secondary sedimentationtank of circumference entrance and exit is selected for biochemical treatment section.Mechanical coagulation&inclined plate sedimentation&fiber rotating disc filter isused in advanced treatment section. The effluent is disinfected by chlorine dioxideand the sludge is treated by the belt thickening and dewatering machine. Biofilter isused in deodorization process.Environmental pollution from urban sewage will be greatly reduced after building upthe wastewater treatment plant in Shuangqing. At the same time, we can improve andenhance the level of infrastructure in Beichen District, as well as natural andinvestment environment, which could contribute a lot to the local development ofeconomy. What’s more, that the effluent quality reaches the level A work in favor ofreclamation and reusage. We can obtain notable economic effect as well.