The Study On Advanced Treatment For Industry Combined Wastewater And Upgrading Reconstruction Of Treatment Plant

With the rapid development of Chinese industry, the discharge amount of industrial combined wastewater is increasing, it results to serious pollution of receiving water environment. Determined by itself water quality, the features of industry combined wastewater is the high concentration of oil pollution and suspended solids. For the plant, it is difficult to treat the decomposition organic pollutants.There are many industry factories and enterprises in the Tiexi district of Shenyang which is the famous industry basis in northeast of China. The discharge wastewater includes pharmacy, coking and brewage ones with the features of typical industrial combined wastewater. Because of difficult and incomplete treatment, the wastewater pollutes the receiving river of Xihe and its main river of Hunhe. To achieve the standard-attainment discharge and reutilization, designs on the whole process treatment for the industrial combined wastewater with the pilot of 2 t/d flow. In the process of pretreatment, uses the coagulation-air flotation to remove the oil pollution and suspended solids from the wastewater, meanwhile remove the phosphorus which leads to the water eutrophication. In this study, the category of coagulant was determined, the pressure solution air flotation was used to remove the residue which constituted by the suspended solids and the coagulant from the wastewater. To improve the biodegradability of industrial combined wastewater quality and make it helpful to the following biochemical treatment, the hydrolysis acidification was studied in the process of pretreatment, which degraded the refractory organics to the low molecular weight ones. In the process of secondary treatment, the biological aerated filter was studied which occupies small space and the quality of effluent is stable, the BAF can remove the organics and the ammonia nitrogen from wastewater. Otherwise the anaerobic was set up before the biological aerated filter, the pre-denitrification function was achieved by the nitrogen water recirculation. This process fully uses the organics of wastewater to be the carbon source, and the outflow total nitrogen meets the discharging standard. For the difficult decomposition and biochemistry treatment of industry combined wastewater, studies on the advanced treatment process involving chemical phosphorus removal, air-floated oil removal, hydrolysis acidification and the anoxic/oxic biological aerated filter, the feasibility of the process and the optimal parameters were determined to achieve the GB code first-level of wastewater discharge.The inflow of the industrial combined wastewater advanced treatment process is from a wastewater treatment plant in Tiexi district. The plant with 40 104t/d flow and GB code second-level of wastewater discharge applies the treatment process of high-density sedimentation sank and biological aerated filter, faces the urgent upgrading reconstruction. According the situation of plant, to meet the discharging standard, the existing process need to plus the ability of nitrogen and phosphorus removal, treat the suspended solids and organic pollutants advanced. The feasibility of the process and the optimal parameters were determined by the pilot, and the theoretical evidence and database can be used to the reference for the upgrading reconstruction of the industrial combined wastewater treatment plant.For the difficult decomposition and biochemistry treatment of industry combined wastewater, studies on the advanced treatment process involving chemical phosphorus removal, air-floated oil removal, hydrolysis acidification and the anoxic/oxic biological aerated filter, proposes the upgrading reconstruction process. Provides the signification of promotion and reference for the plant facing upgrading reconstruction. The feasible implementation program and process were proposed for the pollution of industry combined wastewater to the water environment.