The Process And Operation Effect Of The Standard-Carrying Transformation Of Urban Sewage Treatment Plant

The discharge standard of the early sewage treatment plant in Guangzhou is Grade 1-B discharge standard,which can no longer satisfy the current social development.Guangzhou Municipal Government passed the《Three-Year Action Plan for Water Control in Guangzhou（2017-2019）》,which clearly requires the upgrading and renovation of the existing sewage treatment plants to be completed in 2019,and has established the implementation standard for the upgrading and renovation of the sewage treatment plants in Guangzhou:《Surface water environmental quality standard》（GB3838-2002）,the stricter value for class V surface water.This work first understood and evaluated the water characteristics and operation of the sewage treatment plant in Guangzhou city center and the surrounding area,then upgraded the original A²O process of a sewage treatment plant in Guangzhou Di Biao transformation to ensure the quality of effluent water is stably complied with the《Urban sewage treatment plant pollutant discharge standards》（GB18918-2002）Class 1-A（first grade A）standard and《Surface water environmental quality standards》（GB3838-2002）class V water stricter value,TN≤15mg/L standard.This work analyzed the in and out water quality monitoring data of the sewage treatment plant in 2017,and determined that the main pollutant indexes to be solved in this upgrading and renovation project are SS,TP and TN in turn.Through checking literature,comparative accounting and other methods,finally determined the plan of using the biochemical pool modification+advanced treatment process.The MBBR process is embedded in the biochemical tank to improve the synchronous denitrification and phosphorus removal ability of the system,and a V-shaped filter is added to ensure the stable discharge of effluent SS and other pollutants.In order to determine the effectiveness of MBBR composite technology applied in the improvement project,a pilot test was conducted.The experimental results show that the MBBR composite process still has a certain ability of simultaneous nitrogen and phosphorus removal under the condition with the C/N ratio of less than 3.At the same time,the average values of the effluent COD,NH₃-N,TN and TP of the MBBR composite process are 9.9mg/L,0.56mg/L,6.17mg/L and 0.20 mg/L,respectively,under the impact of 1.4 times of water volume,which indicates that the system has a good capacity of resisting the impact of water volume.The average values of the effluent COD,NH₃-N,TN and TP of the pilot effluent are 18.1mg/L,0.57mg/L,8.05 and 0.20mg/L,respectively,after the addition of landfill leachate with volume ratio of 0.1%to 0.4%,which indicates that the system has a certain anti-landfill leachate impact load performance.After tracking and monitoring the effluent water quality of the MBBR reformed production line and the unreformed production line,it was found that the treament improvement rates of various indexes of the MBBR reformed production line were as follows:NH₃-N increased by 47.11%,TP increased by 1.20%,and TN decreased by 4.47%.A systematic analysis was made on the situation where the effect of the index treatment was not improved significantly except for NH3-N.After adding V-type filter,the average effluent SS,COD and TP of the first,second and third phases of the plant are≤2 mg/L,10.01 mg/L and 0.16 mg/L respectively.The effluent of the sewage treatment plant（including the first,second and third phases）has stably reached the strict value of the class 1 A and the surface Class V water standard,and some of the effluent indexes have reached or even surpassed the surface ClassⅢstandard.Therefore,the expected goal of this bidding transformation project can be completed only by adding V-shaped filter.The successful implementation of the project is of great significance for improving the water ecological environment in Guangzhou,and it can also provide experience and reference for the selection of upgrading technology of sewage treatment plants in South China in the future.