Application Of BioDopp Process In Urban Sewage Treatment Plant

At present,the sewage treatment plant in a very large city in central China mainly uses A/O process,oxidation ditch process,SBR process,etc.,and the tail water discharge of its sewage treatment plant is mostly implemented in accordance with the original Class B emission standards.However,China now requires that wastewater treatment plant discharges be implemented in accordance with the first-level A emission standards,and considering that future emission standards will be upgraded to quasi-Ⅳeffluent requirements,it is necessary to upgrade the WWTP to achieve a quasi-IV discharge standard Water standards.The BioDopp(biomultiplication)process is a process for treating wastewater through biochemical reactions under high sludge concentration.It is optimized based on the traditional A/O process and overcomes the traditional A/O process in terms of energy consumption and organic matter degradation.,Denitrification,excess sludge,etc.It is more convenient and economical to use this process to upgrade the original sewage treatment plant.This test design combines BioDopp high-efficiency aeration technology+ Xylem’s deep-bed denitrification filter.By increasing the sludge concentration and prolonging the sludge age,the microbial environment of simultaneous nitrification and denitrification is maintained.After the system runs stably,the effluent COD is less than 30mg/L,TN<1.5mg/L,can control the sludge concentration at a high level,meet the first-level A emission standards,its compact structure,short process flow,suitable for current urban sewage treatment plants.There is no precedent for using BioDopp technology in central China,so a pilot test is needed to verify its feasibility.In this dissertation,a new sewage treatment plant in central China is taken as an example,and a BioDopp process is used as an experiment.A pilot test is designed and the experimental results are analyzed.The research contents and conclusions of this thesis are as follows:(1)The start-up characteristics of the BioDopp process are analyzed.The research found that the SVI of the BioDopp process was stable at 55.46-7.87mL/g,and MLVSS/MLSS=0.25～0.65.Without the addition of any external carbon source,the removal rate of TN can reach about 80%,and the removal rate of phosphorus can reach about 70%.In the case of adjuvant dosing,the effluent TP is stable below 0.52～0.96mg/L.(2)Explored the debugging and operation of BioDopp process.The average removal rate of COD by this process is 88%,the average removal rate of NH3-N is 93.85%,the average removal rate of TN is 79%,and the average removal rate of SS is 95.85%.When the average value of SS in the water is 186.62 mg/L,the TP in the effluent is basically below 10 mg/L.Meets our quasi-IV water requirements.(3)The removal efficiency along the way of the BioDopp process during stable operation was studied.The research shows that when the system inlet BOD5/COD≈0.5,the inlet BOD5/TP≈20,and the dissolved oxygen content in the stripping zone is about 1.2mg/L,the system has a significant effect on removing organic pollutants.(4)The actual operation of the BioDopp process was analyzed,and it was found that the process achieved a COD removal rate of 89.5%,an average ammonia removal rate of 83.53%,a TP removal rate of 92.67%,and a TN removal rate of 61.01%.After adding Xylem technology,the average COD effluent concentration was 32.93mg/L,the average TN effluent concentration was 5.49mg/L,and the average NH3-N effluent concentration was 3.78mg/L,meeting the requirements for quasi-Ⅳ water.Based on the above test results,and the engineering application as well as economic benefit analysis of the process,a feasible technical support is provided for the upgrading and reconstruction of a new water plant in the later period.