Study On The Security Disinfection Technology Of Combined Processes Based On Ultra-Filtration

Ultrafiltration is particularly effective for removal of particulate matter andpathogenic microorganisms.But it is necessary to combined to pretreatment process toremove small molecular organic pollutants and the poisonous and harmful inorganicmaterial.In addition,in actual operation,ultrafiltration membrane leak individualmicroorganisms,as well as it has twice pollution and microbial reproduction in waterstructures and pipelines.So it is nessary to adopt safey disinfection for the water afterultrafiltration membrane to ensure drinking water biological safety.In view of a reservoir water of Shandong province with high content of organicmatters,algae and the features of ultrafiltration water as well as its requirements oncontinuous disinfection,compared the water purification effect、 microbialinactivation effect、continuous sterilization ability,study of the residual chlorinedecay and biological stability of the process Ⅰ:coagulation sedimentation-sandfiltration-chlorine disinfection, process Ⅱ: coagulation sedimentation-sandfiltration-ultrafiltration-chlorine disinfection, process Ⅲ: coagulationsedimentation--ultrafiltration-chlorine disinfection, process Ⅳ: coagulationsedimentation-powdered activated carbon-ultrafiltration-chlorine disinfection,andfrom the biological safety and chemical safety two aspects to evaluate the chlorinedisinfection safety on different ultrafiltration combined processes. The results showedthat the turbidity of ultrafiltration’s water was below0.10NTU, the process Ⅰ’sturbidity was0.40NTU.The removal of the process Ⅳ’s UV254and CODMnwas thehighest,respectively63.3%and48.2%;In addition,it reduced ammonia nitrogen andnitrite nitrogen to the minimum,respectively0.099mg/L and0.002mg/L.So, processⅣ process had the best water purification.The chlorine disinfection by-products ofprocess Ⅳ was less than0.1mg/L,consisting with the chlorination disinfectionchemical safety requirements;Because of72hour’s residual chlorine in water washigh,it had stronger continuous disinfection ability,it did not detect the total number ofbacteria and E.coil.The AOC content was less than100μgac-C/L,conformed to thesanitary standard for drinking water.With the process Ⅳ’s outlet as the research object,using different concentrationof chlorine、 different concentration of chlorine dioxide and different ratio ofchlorine and chlorine dioxide combined disinfection.Compared their sterilizationeffect and continuous disinfection ability,the content of disinfection by-products.Theresult showed that,considered on the sterilization and disinfection by-products,under the condition of this experiment,the optimus dosage of chlorine and chlorine dioxidewas0.8mg/L and0.4mg/L,0.4mg/L chlorine+0.4mg/L chlorine dioxide was the bestratio combined disinfection.