Study On The Emergent Treatment Of Sudden Taste And Odor Pollution In Fenhe Reservoir

Studies on drinking water emergency treatment have become a very importantresearch area in the21st century’s water supply industry. In recent years, China’s totalenvironment of water body has been in deterioration, and accidental/sudden pollution inwater source happened frequently, which pose a serious threat to the security of urbanwater supply. The traditional technological process “coagulation-sedimentation-filtration-oxidation” which can not effectively deal with sudden pollution in raw water,is adopted by the overwhelming majority water plant in China. In order to improve thesecurity of drinking water, it is essential to carry out studies on the emergent treatmentof sudden pollution in water source.The background of this paper was based on the sudden taste and odor pollutionunderwent in Huyan water plant of Taiyuan City. Fenhe Reservoir, the water source ofHuyan water plant, was investigated during the study. The chemical compound of thetaste and odor and its origin were studied. According to the flavor origin, an emergenttreatment technology suited for sudden taste and odor pollution was chosen aftercomparison, and the operation parameters were optimized by jar experiment. Theengineering project of taste and odor control was designed, followed by the risk analysisof this emergent processing technology.The main conclusions in this study were listed as follows:(1) The water quality of Fenhe Reservoir was in normal level, and all of theindexes investigated during the study satisfied the III level water quality criteria ofsurface water. The TV value of Fenhe Reservoir was0.101, which means this waterbody was in moderate eutrophication.(2) The chemical compound inducing taste-and-odor in Fenhe Reservoir was 2-Methylisoborneol, which was secondary metabolite of algae. The main algae thatcould produce2-MIB was Oscillatoria in Fenhe Reservoir.(3) Huyan water plant failed in taste-and-odor control by dose powered activatedcarbon before the plant, and the reasons were studied during the research. Firstly, theadsorption time was too short for PAC to display its adsorption ability. Second, themajority quantity of2-MIB was stored in the cell of algae, and PAC adsorption was notavailable. Therefore, PAC adsorption technology could not deal with taste and odorcaused by algae in raw water.(4) In order to remove all of the2-MIB in raw water, the majority fraction of2-MIB stored in algae cell should be released out. The paper combined potassiumpermanganate oxidation with powered activated carbon adsorption to deal the waterflavor problem. Potassium permanganate oxidation destroyed the cell of algae, releasingcell-stored2-MIB into water, and powered activated carbon removed it out.(5) The result showed out: the applicable dosage of potassium permanganate was1.5~2.0mg/L, and should not more than2mg/L; Oxidation time of potassiumpermanganate should longer than2hours. The applicable dosage of PAC was20~30mg/L, and adsorption time should longer than3h.(6) The provisional project of PP+PAC technology succeeded in control the tasteand odor in raw water. Result showed that this technology would ameliorate thecoagulation process. Water turbidity in purifying process was lower, the pH was higher,and the NOM removal ratio was higher, all of which upgrading the quality stability ofpipe water.