Removal Effect And Control Method On Carbamazepine And Bisphenol A In Water Treatment System

In recent years,more and more "Pharmaceuticals and Personal Care Product" and "Endocrine Disrupting Chemicals" have been inspected in the waterbody and sewage plant.PPCPs and EDCs from discharging disorderly in human daily life can hardly be degraded by biological treatment.These two substances commonly can not reach the drinking water standard so that they always endanger human health directly or indirectly.This phenomena has attracted a great deal of attention in all countries.The research used conventional process and deeply purifying process to remove PPCPs—Carbamazepine and EDCs—Bisphenol A in feedwater system.and also discuss the removal law and related control technique.Carbamazepine and Bisphenol A are widely deceted by GC/MS or LC,the deceted method is so and tedious and expensive that may not be suit for detecting trace substances in the daily monitoring.Focusing on the limitation,research used HPLC to optimized the detect method and described the detailed steps of SPE.The concrete research results was:(1) The study optimized the detected method of Carbamazepine and Bisphenol A in feedwater systemChromatographic column of HPLC was Agilent ZORBAX Exlipse XDB-C18 (150×4.6mm,5μm).Chromatographic conditions of Carbamazepine:mobile phase—methanol:water=60:40(v/v),velocity was 1mL/min,column temperature is 25℃, wavelength was 284nm,injection volume was 20μL,detection limit was 0.5ug/L, peak flowing out was less than 4.6 min;chromatographic conditions of Bisphenol A: mobile phase-buffer of acetic acid and ammonium acetate(pH=4): acetonitrile=55:45(v/v),velocity was 1mL/min,column temperature was 25℃, wavelength was 276nm,injection volume was 20μL,detection limit was 0.5ug/L, peak flowing out was about 5 min.Detection precision of the two substance was high with favorable recovery rate and their relative deviation were both less than 1. (2) The study proved the transformation law and the best regulation parameters of Carbamazepine and Bisphenol A in the conventional process.The research investigated that Carbamazepine and Bisphenol A hadn't any by-product after potassium permanganate oxidation through GC/MS and recognized the coagulation mechanisms of the two substance were both adsorption and charge neutralization by ZETA potential instrument.Oxidation time of Carbamazepine and Bisphenol A were 50 min and 30 min respectively,dosing quantities in the correction experiment were 2 mg/L.the most suitable coagulant was PAC during choosing from PAC,PFS and ferric chloride.The best PAC dosing quantities of Carbamazepine and Bisphenol A in the correction experiment were 2.5mg/L and 3mg/L,removal efficiency of Carbamazepine and Bisphenol A were 39.6%and 34.5%respectively. COD_Mn,UV₂₅₄ and turbidity could also be removed with high efficiency which was in the range from 45%to 60%.The function of sand filtration was to intercept the micelle and SS from coagulation..The removal efficiency of Carbamazepine and Bisphenol A increased with increasing heightof sand layer.Residence time depanded on filtration rate. Removal efficiency was high with slow filtration rate,but minimal filtration rate was not suitable for practical engineering.So we chose 5.86m/h and 800mm as the best filtration rate and heightof sand layer with its removal efficiency of Carbamazepine and Bisphenol A were 10.95%and 8.3%respectively.The removal efficiency of turbidity could also reach to 93.4%.(3) The study proved the transformation law and the best regulation parameters of Carbamazepine and Bisphenol A in the ozonation and activated carbon process.Ozonation and activated carbon is a kind of deep-purifying process.Through GC/MS,the study found that Carbamazepine had a by-product—Futamoto Acetonitrile with a spot of content after ozonated.Bisphenol A didn't have any by-product.When the influent density of Carbamazepine and Bisphenol A were 200ug/L,dosing quantities of ozone were 20.87mg/L and inflow discharges were 15L/h,the two substance could both reach the largest removal efficiency—32.3% and 28.2%respectively.The removal efficiency of COD_Mn and UV₂₅₄ could also reach to 67.3%and 63.4%.Through iodine value,test,specific surface area test and static adsorption test, study chose fruit shell activated carbon as the best carbon with high removal efficiency to Carbamazepine and Bisphenol A.As for Carbamazepine,when the initial concentration was 25mg/L,adsorption time was 60 min,dosing quantity of carbon was 5g/L and pH was neutral,the removal efficiency of Carbamazepine was 84.86%,its adsorption could reach to 11.87 mg/g.As for Bisphenol A,when the initial concentration was 25mg/L,adsorption time was 90 min,dosing quantity of carbon was 6 g/L and pH was neutral,the removal efficiency of Bisphenol A was 76.08%,its adsorption could reach to9.75 mg/g.The adsorption isotherm of Carbamazepine and Bisphenol A is of typeâ… which could be described by Langmuir adaorption equation.This proved that Carbamazepine and Bisphenol A was adaorped on the surface of activated-carbon by per-molecule form.And the Dynamic adsorption study showed that the process of activated-carbon could not only remove Carbamazepine and Bisphenol A in the source water with high effects,but also had a satisfactory removal effect of some pollution indicators,such as COD_Mn,UV₂₅₄ and turbidity.When the height of carbon was 800mm and filtration rate was 5.86m/h,the largest removal efficiency of Carbamazepine and Bisphenol A could reach to 85%and 80%.The removal efficiency of COD_Mn,UV₂₅₄ and turbidity were 68.6%,71.6%and 87.4%.The by-product of Carbamazepine after ozoned couldn't be detected any more which showed that Futamoto Acetonitrile was removed completely or its concentration was less than the detection limit—0.05ng/L.It meaned that there was not secondary pollution in the ozonation and activated carbon process,effluent hadn't any by-product which was harm to human health.Considering the high removal efficiency of activated carbon,we could use activated carbon process as the dominant process in practical engineering.(4) The study proved the practicality of compounding technics to remove Carbamazepine and Bisphenol A.Every separated process mentioned above was integrated for continuous experiment with those optimum conditions.In the 15 days of experiment,average removal efficiency of Carbamazepine and Bisphenol A could reach 92.8%and 89.4% with stable effluent.Pollution indicators of COD_Mn,UV₂₅₄ and turbidity also reached high removal effects.Their average removal efficiency were 81.7%,78%and 95.5%. The effluent of devices was stable.The study was of large practical value which supplied steady theoretical basis and technical reference for removing PPCPs and EDCs in the feedwater system.