Experimental Study On Reverse Osmosis In Advanced Treatment Of Municipal Sewage For Sulfonamide Antibiotics

It is an effective way to solve water shortage that reuse the municipal wastewaterafter advanced treatment.The water after secondary biochemical treatment by the urbansewage treatment plant still contains some PPCPs. As the removal efficiencies of themin wastewater treatment plants are unsatisfactory nowadays. So these micro-pollutantscould be enter into the water environment and could occur and render adverse effectson ecosystem and human health.Antibiotics are the more important class of PPCPs and are widely used. So therewas an important practical significance to study on the removal of trace amounts ofantibiotics. In this paper, contact filtration-fiber filter-activated carbon-the reverseosmosis process was used to treat secondary effluent of municipal wastewater plant.Discussed and analyzed the device characteristics and the design parameters of contactfiltration. Analysis of the various parts of the water quality, sand filtration and reverseosmosis membrane cleaning.Through static beaker experiment compared the coagulation effect for three kindscoagulant of FeCl3, Al2(SO4)3and PAC. According to the results, select PAC as coagulant,and studied pH and temperature on coagulation. Through experimental analysis, sandfilter column filtration speed of4m/h and coagulant dosing quantity of20mg/L. Sandfiltration column adopted joint air and water backwash, backwash cycle for13h; the theair impact strength and washing time were16L/m2s and1.5min; when joint air andwater flushing, the gas flushing intensity, water flushing intensity and washing timewere16L/m2s,4L/m2s and4min; finally the water washing strength of8L/m2s,washing5min.Pretreatment average removal rate of turbidity, TN, TP, CODcr, UV254, TOC andsulfonamide antibiotics were89.5%,18.9%,51.9%,59.7%,27.6%,30.8%and8.0%to50.2%. Combined process on turbidity, inorganic salts, TN, TP, CODcr, UV254, TOCand sulfonamide antibiotics, the average removal rate were96.1%,97.8%,88.3%,99.4%,85.9%,98.3%,89.4%and100%.In addition sulfanilamide and sulfadimethoxine, the remaining seven sulfaantibiotics were detected in the sewage treatment plant influent and effluent, theconcentration range respectively0.617~5.429μg/L and0.431~2.267μg/L, and detection rate of them in influent and effluent were more than73%. Sulfonamide antibiotics inthe municipal sewage treatment plant can not be completely removed, the removal ratewas-12.0%to73%. The results showed that in pretreatment process, the removal ratesof seven sulfonamides antibiotics were13.3%~16.9%,4.1%~19.3%,14.1%~37.4%,5.72%~28.8%,35.2%~62.4%,1.78%~59.6%,0.7%~27.8%. In combined process, theremoval rate of seven sulfonamides antibiotics were100%. The influence oftemperature on the performance of reverse osmosis membrane was studyed, the resultsshow that the membrane flux and salt rejection decreases as the temperature decreases,membrane flux within certain limits of temperature, flux and temperature were linearrelationship exists, and linear significantly.Through experiment, through the first2.0%C6H8O7, and0.5%of NaOH onmembrane for chemical cleaning.