Research And Demonstration On Advanced Treatment Process Of Micro-polluted Water

Drinking water pollution and micro-polluting species keep a sustainable growth with the industrial development and accelerated urbanization process,which makes the water slightly polluted,and Conventional water treatment processes are difficult to effectively remove micro-pollutants,which makes the drinking water quality and safety of biological stability become a great challenge.Therefore,it is very important and urgent to carry out the research on advanced treatment technology for micro-polluted water.This paper firstly investigates the situation of polluted water intake,excess pollutants and water treatment processes of plants in Jiangsu Province.According to the raw water quality of Huai River（Yang cheng part）,to reduce the Organic Pollutants,Disinfection by-product formation potential,which aims to Protect water quality and biological stability.This paper focus on follow three areas:（1）Water quality survey;（2）Research on the optimization of advanced treatment process.The effects of different coagulants（PAC）dosage,ozone dosage of pre-ozone unit,ozone dosage and contact time O₃-BAC unit were investigated.To explore the best operating conditions for advanced treatment process,it will provide reference for advanced treatment processing demonstration project operation;（3）Combined with pilot test,it willfocus on the demonstration project advanced development process.optimized for ozone dosage of the pre-ozone unit and 0₃-BAC unit.To compare the conventional treatment process with the advanced treatment process,and highlight the advantages of advanced treatment process of pollutants removal.It is shown that the polluted water intake in the Huaihe River and dissolved oxygen,CODcr,CODMn,NH₄⁺-N,Mn²⁺ and petroleum exceeded the situation is much more serious;Most of the water plants in Jiangsu Province are still dominated by conventional processes.Some of those plants are equiped with advanced treatment technology,which are dominated by Ozone biological activated carbon process.（1）Research on the optimization advanced treatment process.Focusing on DBPFP,ozone oxidation by-products:such as bromate（BrO₃^-）,formaldehyde（CH₂O）and BDOC removal characteristics.It is shown that when the dosage of PAC is 30 mg/L,the conventional treatment process has good removal effect on each pollutant.The removal rates of the TTHMFP and THAAFP were 36.6%and 61.2%.But the water content of BDOC is higher,and the biological stability is difficult to protect,which needs to use the further development treatment to protect the water quality of biological stability.The pre-ozone unit has a certain effect on the organic matter.When the ozone dosage was 1.1 mg/L,the removal rates of CODMn,UV254 and TOC were 15.2%,23.6%and 21.4%.But the BDOC content increases after pre-ozone unit,which makes the biological stability of water quality decreased,so it needs to rely on the follow-up further development processing unit for further processing.When the dosage of ozone was 1.1 mg/L,the removal efficiency of THMFP and HAAFP was 20.4%and 42.3%.The content of BrO₃-in the effluent is lower than the test line（0.02 μg/L）,and the formaldehyde content is between 30-71 μg/L,which is much lower than the national water quality standard.Fix the ozone exposure time is 30 min,and when the main ozone dosage is 2 mg/L,the removal rates of CODMn,TOC and UV254 was 52.2%,56.6%and 61.2%,BDOC was 76.8%,and the removal rates of TTHMFP and THAAFP were 53.1%and 44.0%.The ozone dosage of the main ozone unit was 2 mg/L,and when the ozone contact time was 50 min（BAC unit corresponding to EBCT was 21.3 min）.The removal rates of CODMn,TOC and UV254 were 73.7%,63.7%and 93.5%,respectively,BDOC was 87.6%,Therefor the biological stability of the water greatly improved.The removal rates of TTHMFP and THAAFP were 69.4%and 44.6%.（2）Combined with pilot research results,Research on optimizing demonstration project of advanced treatment process based on Yancheng water plants in Yancheng City,and follow-up monitoring the whole process of water treatment for a one-year.And optimize the ozone dosage of O₃-BAC unit.It is shown that the removal rates of CODMn,TOC and UV254 were 13.3%,7.7%and 32.8%,TTHMFP and THAAFP removal rates were 36.1%,51.7%,When the ozone dosage was 1.8 mg/L,the removal rates of CODMn,,TOC and UV254 was 52.2%,56.6%and 61.2%,when the 03-BAC advanced treatment unit was the best.Fixed pre-ozone dosage 1.1 mg/L,and the main ozone dosage of 1.8 mg/L.The removal rates of TTHMFP and THAAFP were 21.9%and 63.2%,which indicates that the advanced treatment in the optimal conditions can effectively remove the DBPFP content,so as to the output of water DBPs.The removal rate of BDOC was 82.5%,the content was about 0.2 mg/L,and the biological stability of effluent was greatly improved.The removal rate of turbidity and CODMn in the advanced treatment process was significantly higher than that in the conventional treatment process,and the turbidity of the plant water was lower than 0.2 NTU and CODMn was stable below 2 mg/L.It is shown that the pre-ozone treatment process has a pre-ozone dosage of 1.1 mg/L and a main ozone dosage of 2 mg/L,which has a significant removal effect on each pollutant and ensures water quality safety and biological stability.Its optimized operation results have a certain guiding effect on the regulation and control of the advanced processing demonstration project.