Research On The Application Of The Membrane Technology For Water Treatment In The Rural Areas Of Chonqing

In recent years,with increasing shortage of water resources and the development of national standards for drinking water,the traditional conventional water treatment process has been difficult to meet the safety requirements of drinking water,so exploring a new economic and practical water treatment method is a major issue which is placed in front of the water treatment technology workers.The main topic of this study is to explore the treatment effect that hollow fiber membrane modules and flat membrane module processing purify the rural water in Chongqing and the pressure changing process of the transmembrane flux membranes and TMP. It will lay the foundation for the practical application of membrane technology in Chongqing mountain rural safety water supply.The subject studies on Chongqing rural safety drinking water demonstration research,which is using plate ultrafiltration membrane and fiber filtration membrane.The direct filtration test is analyzed for the removal of contaminants from Chongqing rural water systematically.According to the problems which is found in the process of direct filtration process,we have upgraded the direct filtration technology.In response to the disadvantage of direct transport in the presence of the filtration,we enhanced the performance of its operation and the removal of contaminants,and increases step process-coagulation in front of the direct filtration pretreatment process.it also enhances the operation and removal of contaminants performance. the main results are as follows:(1)Flatbed fiber filtration membrane filter #1,#2,#3 types of water samples directly, the removal of water samples’ turbidity are more than 95%.The plant operations’ water quality is below 1NTU stably after ten days of continuous operation.The removal of turbidity of filtration membranes is not affected by changes in raw water quality.Flatbed fiber filtration membranes achieve better removal of UV254 in the raw water.There is a huge difference among different water qualities in the removal process.After continuous operation,the equipment still has a stable removal of UV254. Flatbed fiber filtration membranes achieve bad removal of CODMn in the raw water.After 10d’s continuous operation, the removal of CODMn through the filtration device begins to stabilize at a low leve.(2)The hollow fiber membrane module ultrafiltration membrane filter #1,#2,#3 types of water samples directly, the removal of water samples’ turbidity are very well. The plant operations’ water quality is below 1NTU stably after ten days of continuous operation. The removal of turbidity of ultrafiltration membranes is not affected by changes in raw water quality.Hollow fiber ultrafiltration membranes achieve better removal of UV254 in the raw water.There is a huge difference among different water qualities in the removal process. After continuous operation,the equipment still has a stable removal of UV254.Hollow fiber ultrafiltration device achieved bad removal of CODMn in the raw water.CODMn in the effluent exceeded 3.0mg/L as the drinking water health standard saids.As the further extension of equipment operating time,CODMn removal stabilized.(3)The process which combined device treating #1,#2,#3 type of water samples can improve the trans-membrane flux membranes.As the removal of turbidity, UV254,CODMn in raw water just to meet the drinking water standards,it was determined the optimal dosage of PAC.As PAC-MF combined process was used to treat #1,#2,#3 types of water samples,we determine the optimal investment coagulant dose of PAC were 3mg/L, 7mg/L, 5mg/L finally.As PAC-UF combined process were used to treat #1,#2,#3 types of water samples,we determine the optimal investment coagulant dose of PAC were 4mg/L, 6mg/L, 4mg/L finally.(4) Flat microfiltration apparatus for processing #1,#2,#3 water samples before running 20 minutes, the total amount of trans-membrane pressure rose amount of 50%,70%,67% of total lift amount respectively. TMP increased with the time. Impact of physical cleaning on the membrane is higher than the pressure on membrane. TMP revert to 95%,90%,89% of the original flux through physical cleaning. Physical cleaning with a short time can restore membrane films basically. As flat micro-filtration apparatus for processing #1, #2, #3 water,the optimum hydraulic cleaning cycle were 50 min, 30 min, 40 min respectively.(5) Hollow fiber ultra-filtration device apparatus for processing #1,#2,#3 water samples before running 10 minutes,the total amount of trans-membrane pressure rose amount of 54%,80%,75% of total lift amount respectively. TMP increased with the time. Concentration polarization effect of the membrane surface of the cake layer is formed mainly at this time. Impact of physical cleaning on the membrane is higher than the pressure on membrane. TMP revert to 97%,90%,93% of the original flux through physical cleaning. Physical cleaning with a short time can restore membrane films basically. As hollow fiber ultra-filtration device apparatus for processing #1,#2,#3 water,the optimum hydraulic cleaning cycle were 50 min, 20 min, 30 min respectively.(6) Chemical cleaning of the membrane module must choose the right cleaning chemicals according to the type of contaminants and in accordance with certain steps to clean and orderly conduct of the order. and it will reach the deep cleaning effect on the membrane.(7) After the equipment is out of service,we must be taken regularly for its trial run, mildew, freezing measures in order to ensure its normal working condition and performance. The measures as follow when the devices need to be taken down for maintenance.after equipment is out of service,it should continue to maintain a moist state and pay attention to the surface of the antibacterial and antifungal, anti-freeze in some areas also.