The Application Research Of Micro-polluted Source Water With Enhanced Coagulation-Ultrafiltration Technology

Ultrafiltration as an advanced water treatment process has been used widely in water andwastewater treatment because of its advantages such as simplified device, small footprint andwide application range. However, there are several deficiencies by ultrafiltration, such asremoval efficiency of organic matter is not enough; membrane fouling leads to high cost.Coagulation technology appears to yield some beneficial effects when as a pretreatmentmembrane filtration because of its low cost and simple operation, which can improve theultrafiltration technology for water and wastewater treatment effect, reduce membrane foulingand decrease cost. So link ultrafiltration process and coagulation process of enhancedcoagulation-ultrafiltration process has been extensively studied which as a advanced watertreatment technology,In this paper, three kinds of PES ultrafiltration membrane was first prepared, and thethree kinds of ultrafiltration membrane applied to single ultrafiltration process and enhancedcoagulation-ultrafiltration process. The experiment studied the treatment effect ofmicro-polluted source water by different processes and the operation conditions ofultrafiltration membrane. The results showed that:(1) Two kinds of stain resistance PES ultrafiltration membrane (PES/nAg ultrafiltrationmembrane and PES/nTiO2ultrafiltration membrane) was obtained by orthogonal experiment.The PES/nAg’s pure water flux and rate of BSA rejection is354.21L/m2h,95.82%andPES/nTiO2’s is363.74L/m2h,92.71%. Stain resistance PES ultrafiltration membrane ishigher than traditional membrane on pure water flux and rate of BSA rejection. Two kinds ofstain resistance PES ultrafiltration membrane is prepared on the basis of traditional membrane,which have a higher water flux and rejection rate.(2) When single ultrafiltration process handles micro-polluted source water, PES/nTiO2ultrafiltration membrane> PES/nAg ultrafiltration membrane> traditional PES membrane onmembrane stain resistance. That stain resistance ultrafiltration membrane has a higherpollution resistance, more water been processed, longer service life than conventional PESultrafiltration membrane. PES/nAg ultrafiltration membrane’s removal rate of UV254, UV278is33.33%,35.77%. It’s best among the three ultrafiltration membrane on the water quality indicators.When single coagulation treatment process handles micro-polluted source water,the use of AS+PD is higher than single coagulant on organic matter removal efficiency.When the ratio of coagulant is AS5mg/L+PD3mg/L, the removal rate of UV254, UV278is69.81%,70.94%. At this point the removal rate is best.(3) When enhanced coagulation-ultrafiltration process with traditional PES membranemanages micro-polluted source water, the removal rate of UV254, UV278is66.25%,69.25%.In this case the coagulant is AS5mg/L+PD2mg/L and ultrafiltration membrane’s waterstable value is11.38g (interval of30s).When enhanced coagulation-ultrafiltration processwith PES/nAg membrane handles micro-polluted source water, the removal rate of UV254,UV278is71.28%,71.71%. In this case the coagulant is AS1mg/L+PD2mg/L andultrafiltration membrane’s water stable value is12.04g (interval of30s). When enhancedcoagulation-ultrafiltration process with PES/nTiO2membrane handles micro-polluted sourcewater, the removal rate of UV254, UV278is69.91%,70.6%. In this case the coagulant is AS2mg/L+PD2mg/L and ultrafiltration membrane’s water stable value is17.81g (interval of30s).(4) In enhanced coagulation-ultrafiltration process PES/nTiO2ultrafiltration membrane isthe best among the three on membrane’s water stable value. Followed by PES/nAgultrafiltration membrane and the last is traditional PES ultrafiltration membrane. From theremoval efficiency of organic matter PES/nAg ultrafiltration membrane is the best among thethree. Followed by PES/nTiO2ultrafiltration membrane and the last is traditional PESultrafiltration membrane. Taken together, stain resistance is better than conventional PESultrafiltration membrane in terms of water purification.(5) If the coagulant is AS+PD, then enhanced coagulation-ultrafiltration process is betterthan single coagulation process, because of it is lower coagulant dosage. On the basis ofguarantee the quality of water enhanced coagulation-ultrafiltration process can reduceoperating conditions of coagulation process. Enhanced Coagulation can filter more water thansingle ultrafiltration in unit time and has lighter membrane fouling.