Activated Carbon Fiber Catalytic Ozonation Oxidation For Treatment Of Nanofiltration Concentrated Water

Nanofiltration has been widely used in advanced treatment of reclaimed wastewater, this paper main research on the treatment of concentrated water in purification process by nanofiltration membrane. At first,the nanofiltration membrane advanced treatment efficiency of secondary effiuent was investigated. Secondly, the Activated Carbon Fiber was used an ozone catalytic material, and it was modified by nitric acid and its characterization was carried out. Finally, Study treatment effect on the modified activated carbon fiber catalytic ozonation of nanofiltration concentrated water at different ozone concentration、hydraulic retention time and temperature conditions, the conclusions of the study are as follows:(1) The nanofiltration membranes are used to removal contaminants of secondary effiuent. It shows that the removal efficiency of COD 、TOC、NH3-N、TN、TP、UV254、Conductivity and SDI are 71.08%、 72%、44.8%、72%、63.8%、82.86%、86.5% and 90%,and contaminants of nanofiltration Concentration water is higher than the grade V standard of surface water.(2) The results of modified activated carbon fiber were compared with 5%HNO3, 10%HNO3 and 20%HNO3: According to the analysis of BET, Scanning ElectronicMicroscope(SEM), the specific surface area and micropore Pore volume of activated carbon fibers decreased after the modification of nitric acid. From the view of pore size distribution, the number of mesopore and ectopore and aperture of activated carbon fibers were significantly increased after 5%HNO3 modified, 10%HNO3 and 20%HNO3 surface features compared to pure water was not very obvious. The adsorption rate of methylene blue was 20%HNO3 < pure water <10%HNO3 < 5%HNO3.(3) The static test results of the activated carbon fibers catalytic ozonation oxidation showed that: the Ozonation alone、added activated carbon fiber of Ozonation oxidated nanofiltration Concentration water,at 30 min, the removal efficiency of UV254 are 43% and 58%, and the removal efficiency of COD are 67% and 71.%; At 60 min, the removal efficiency of UV254 increased to 53% and 71.7%, and the removal efficiency of COD increased to 70% and79%.(4) The dynamic test results of the activated carbon fibers catalytic ozonation oxidation showed that: With the increase of ozone concentration, the removal rate of UV254 and COD of concentrated water increased.Increased hydraulic retention time, the removal rate of UV254 and COD was not significant. At 5℃and 10℃of text, the removal efficiency of UV254 and COD average increased by 20.2% and 7.25%.(5) In the ozone concentration 8mg/L、 hydraulic residence time for 30min、temperature 10℃, modified activated carbon fiber catalytic ozonation oxygenation nanofiltration concentrated water,the COD of reach the III grade discharge standard of surface water environment.