Study On The Design And Application Of Integrated Coagulation-ultrafiltration Water Supply Purification Device

In recent years,ultrafiltration membrane technology has been used more and more widely in water treatment.However,the membrane fouling and the low treatment efficiency of organic matter in water still exist in the process of using ultrafiltration membrane.These problems seriously restrict the popularization and application of ultrafiltration membrane technology.In view of these problems,in this paper,the PVDF hollow fiber ultrafiltration membrane prepared by our team was used to design and manufacture an integrated coagulation-ultrafiltration water supply purification device.The surface water in the experiment is surface II water and surface inferior V was treated by the integrated coagulation-ultrafiltration water supply purification device.Meanwhile,the PVDF hollow fiber ultrafiltration membrane was applied to treat the effluent from the sedimentation tank of the water treatment plant.The main conclusions are as follow:?1?In the process of surface water treatment,there are two processing modes in the integrated coagulation-ultrafiltration water supply purification device,including direct ultrafiltration and coagulation-ultrafiltration.Compared with coagulation-ultrafiltration membrane,flux of direct ultrafiltration decreased more rapidly.In the first 5 hours of operation time,membrane flux of two modes decreased quickly,and then tended to be stable after operation for 48 hours.?2?The integrated coagulation-ultrafiltration water supply device has better removal efficiency for turbidity of surface water,and the turbidity of the effluent is below 0.1 NTU.The turbidity of the effluent remains stable,and the removal rate is above 95.5%.The effluent is not affected by the turbidity of the water and the effluent is stable.The integrated coagulation ultrafiltration water supply and purification device have good retention ability for bacteria in water.In 48 groups of water samples,6 colonies were not detected.?3?When surface water is treated by two ways,direct ultrafiltration and coagulation-ultrafiltration,coagulation-ultrafiltration can effectively improve effluent quality.The removal of COD,UV₂₅₄,NH₃,total aluminum and TOC pollutants are the optimum when the dosage of PAC is 6 mg/L.?4?The turbidity of ultrafiltration membrane is generally below 0.1 NTU after the treatment of the effluent from the sedimentation tank of the water treatment plant,and the removal rate is above 96%.Turbidity of effluent is far lower than that of the filter treated effluent.The ultrafiltration membrane had better effect on the COD_Mnn treatment of the effluent from the sedimentation tank than that of the filter treatment,and the average COD_Mn concentration of the ultrafiltration membrane was 2.3 mg/L.The integrated coagulation-ultrafiltration water supply purification device has a stable operation process,high degree of automation,small area and low cost of treatment.It can be applied in remote areas and rural areas which are not suitable for the construction of water purification plants,and can also be applied for emergency water treatment.The integrated coagulation-ultrafiltration water purification device has a good market prospect.