The Effect Of Ultrafiltration On Water Quality And Pipe Corrosion

The quality of drinking water and residential water safety has a direct close contact. In the past only water quality objectives of the finished water was concerned,water quality deterioration of the secondary pollution of the pipe network was paied insufficient attention to.More than 90% of water supply pipe cast iron pipe which with the rough inner wall, and is conducive to microbial attachment and reproduction,pathogens hiding in the inner wall directly threat the safety of drinking water, affect the water quality and stability of water supply pipe network.The new generation of water purification process with the ultrafiltration technology as its core,high safety process.Received extensive attention as water quality and reliability.There is no bacteria and most organic available microbially.Especially in the safety and stability of the water has very good effect.Pilot test platform was established in the experiment, anddaily maintenance of the ultrafiltration membrane was explored,which daily cleaning method is60s’ backwashing with 30s’ surface washing,and cleaning frequency is 60 min once.The off-line chemical cleaning method is that using sodium hypochlorite and oxalic acid composition as reagent of the surface washing.Ultrafiltration systemhas a extraordinary removal of dimness、Escherichia coli andalgae.but it`s has a low removal of UV254 and genetic toxicity.In pipeline corrosion test,the result shows that the pipeline effluentwithout utrafiltration system has a greater decrease in sulfate, aluminum, nitrate and pH, also has a greater increase in total iron than which with utrafiltration. After all ultrafiltration system has a substantial improvement on the corrosion of pipeline,16S rDNA genetic libraries were built up,which shows that the biofilm from the lined steel pipeline without ultrafiltration treatment,Brevundimonas(7.14%),Hydrogenophaga(59.52%), Bosea(2.38%), Sphingopyxis(14.29%),Sediminibacterium(11.90%) were identified. And from steelline pipe without ultrafiltration treatment Aquabacterium(15.91%), Hydrogenophaga(66.77%),Flavobacterium(4.26%), Sphingomonas(4.26%), Sediminibacterium(2.27%) were identified.The biofile of pipeline were cultured by iron bacteria enrichment, it shows that after ultrafiltration treatment, the culture result is negative, the culture result is positive while without ultrafiltration treatment. The gene test shows that the iron bacteria is belong to Sediminibacterium.The sludge from pipeline were cultured by sulfate reducing bacteria enrichment,it shows that after ultrafiltration treatment, the culture result is negative, the culture result is positive while without ultrafiltration treatment. The gene test shows that the sulfate reducing bacteria is belong to Desulfovibrio.