Technology Of Remove The Odor Secretions Of Algae In Drinking Water By Ferrate

Dimethyl trisulfide as the secondary pollutants which produced byalgae in water bodies, caused the accident in drinking water for the taste ofcorruption. usually, it can be perceived by the user with the existence of10ng/L in drinking water.A one-year-long investigation on micro pollutants in water source ofHangzhou was carried out including the microbiology source of odors andidentification of the substances causing odors.The results show that thediatoms and chlorella have the highest content and Anabaena, Oscillatoriaalgae and microcystins were followed by. Odor substances were mainlyconcentrated in7-8months, The highest content of GSM was44.7ng/L,The highest content of2-MIB was89.4ng/L, the highest content ofdimethyl trisulfide was35.2ng/L, and found that dimethyl trisulfide wascaused mainly by Oscillatoria algae.Simple and accurate analysis methods with the liquid-liquid extractioncoupled with gas chromatograph for detecting trace odorous compound-dimethyl trisulfide was established. The pretreatment with Less analysistime（10min） and less consumption of organic solvent（1ml） is applicable tothe analysis of large numbers of samples. The recovery rate and the relativestandard deviation （RSD） are86.8%to93.1%and2.5%respectively.High purity ferrate was prepared by optimizing the electrolysisconditions，and the stability of ferrate was achieved through the additivesolution.a study on oxidation of dimethyl sulfide and algae by ferrate isconducted, and compared with the potassium permanganate oxidation,potassium permanganate pre-oxidation combined with coagulation.The oxidation effect of dimethyl trisulfide by potassium permanganate and potassium ferrate is compared. The results showed that the oxidationreaction of dimethyl trisulfide by potassium permanganate was veryefficient, The rate of dimethyl trisulfide decomposition by potassiumpermanganate in aqueous solution followed second—order kinetics and thesecond-order reaction rate constant was k=0.00213L/（min·mg）. thereaction rate constant was increased with the increasing initialconcentration of potassium permanganate. The reaction rate constant ofdimethyl trisulfide was without the obvious affected by the initialconcentration of dimethyl trisulfide、pH （5.15～9.04） and CODMn（1.8～4.5mg/L）， and the reaction rate constant was decreased with theconcentration of β-Cyclocitral changing from0～1886μg/L。The rate of dimethyl trisulfide decomposition by potassium ferrate inaqueous solution match third-order kinetics and reaction rate constant wask=6.57×10^-10L/（s·mg）.Results of influence experiments showed that K was little fluctuatedwhen organic substrate of humic acid added（CODMnin the range of1.8～4.5mg/L）, while it was decreased with the concentration of β-Cyclocitralraised from0to1556.3μg/L.Odor substances in this study mainly relies on the existence of algae,so the impact of algae should be considered in odor removal. Potassiumferrate has the dual effect of oxidation and coagulation, the commonremoval of algae and odor can be achieved by taking advantage of its rolein coagulation. the result shows the removal rates of odor and algae canreach25.2%,89.8%at the PFC dosage of21mg/L. potassium permanganatecombined with PFC can significantly improve the removal efficiency ofodor and algae. the removal rates of odor and algae can reach90.9%,94.8%at the potassium permanganate dosage of6mg/L. the removal rates of odorand algae can reach68%,88%at the ferrate dosage of20mg/L and92.4%,92.5%at the ferrate dosage of40mg/L. so the removal of secondaryodor pollutants and algae is good by the role of ferrate.