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With increasing demand for high quality of people’s life hygiene and safety issues of drinking water get more and more the concern of the community while the implementation of the new standards of water quality also put forward higher requirements to the quality of water supplies. Low temperature and turbidity water purification process is one of the problems of the water supply industry and the improper process selection is often caused by high dosages, increased costs, water quality is less than ideal results. Topics based coagulation theory and enhanced coagulation theory, the pilot test, low temperature and turbidity Yellow River surface water treatment coagulant optimization and selection, dose optimization, and through pharmaceutical compounding, powder activated carbon dosing remove water disinfection byproducts precursors and induced olfactory substances.Based on hydraulic calculation, this subject optimize experimental apparatus hydraulic optimization through orthogonal experime. The preferred pilot experiment mixed pools and three flocculator’s G was800s-1/24s-1/64s-1/28s-1.Though the analysis of the poor result can also be seen, Stir the pool G value on the coagulation effect is the largest, the third stage flocculation tank mixing G value is a secondary factor affecting the coagulation effect.Preferred waterworks three the polymerization class aluminum and iron salts optimize the dosing interval, and on this basis through small beaker test pilot test. By changing the amount of coagulant dosing study water after filtration turbidity, COD, UV254, chromaticity and residual metal content, and found three kinds of coagulants for overtime PFAS alone is optimal, in adding the dose of25mg/L on the various indicators removal effect is the best. Due to the heavy water itself iron content is higher, Additive polymerization iron sulfate after make the residual iron content and chroma exceeds bid. In coagulant aid strengthening coagulation experiments found that activated silicic acid and PAC to1:5ratio, amount of PAC dosing30mg/L or activated silicic acid with PAFC with1:3proportion of PAFC, dosing quantity is25mg/L effect is better in two ways, the actual production according to the labor and production costs are calculated and determined in the process.The article also explores the removal of enhanced coagulation of disinfection by-product precursors and olfactory substances. Based on the PAC as coagulant, Enhanced coagulation by KMnO4and FeCl3jointly with separate dosing PAC when compared COD removal rate increased from18%to20.5%, the disinfection byproducts chloroform reduce about11%, approximately20%of the the chloral generated content reduced, Potassium permanganate/polymerization ferric chloride the enhanced coagulation also make the trichloromethane generate less than0.5, Better inhibition of the formation of chloral, chloride produce the amount of filtered water two hours2.0μg/L or less.Induced olfactory substances experiments on raw water in removing multiple consecutive sampling and analysis, the smell is given priority to with stench, and accompanied by soil musty, and analysis of sources of pollution by substances detected, mainly include2-cyclohexen-1-one,1-cyclohexanol-2-ethyl group, a phenol, and xylene, etc. like substances. Experiments found that the water smelling substance and algae removal effect and powder activated carbon additive quantity is related, and the residence time of growth as the powdered activated carbon contact, the smelly threshold decreased, activated carbon adsorption to the smelly substance to water bodies in the top80min adsorption rate is fast, When activated carbon dosage was increased by5mg/L to10mg/L, The cause of smelly material removal rate is basically the same as the first80min, residence time of2h, smelly threshold removal rate increased from72.1%to83.1%, the removal efficiency improve slightly.
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