Performance And Mechanism Of Typical Pharmaceuticals And Personal Care Products Removal From Water By The Hybrid Processes Of Granular Activated Carbon And Ultrafiltration

Pharmaceuticals and personal care products （PPCPs） in drinking water havebeen receiving extensive attention all over the world. However, no paper hasbeen reported about them in China. In this study, occurrence, fate and effect of39PPCPs in drinking water were investigated in southern China by highperformance liquid chromatography and tandem mass spectrometry（HPLC/MS/MS）. Hybrid processes with granular activated carbon （GAC） andultrafiltration （UF） was developed based on the characteristics of climate andsource water quality. Performance of the hybrid processes in the removal oftypical PPCPs and other pollutants was evaluated. Behaviors and mechanisms oftypical PPCPs removal by the hybrid processes were investigated. A full-scalewater treatment plant was established on basis of the experimental results, withthe capacity of400000m³·d^-1.The concentrations of sixteen PPCPs detected in source water were ND²7ng·L^-1. Twelve PPCPs were detected in treated water, with concentration ofND⁵ng·L^-1. Advanced treatment processes were more efficient in the removalof most PPCPs than conventional treatment processes. Fifteen and seventeenPPCPs were detected in pipeline and tap water, respectively, with concentrationof1ng·L^-1. Typical PPCPs mixture had an influence on zebrafish embryodevelopment at the level of ng·L^-1. Some potential ecological and health riskscaused by PPCPs existed for water sources in southern China.Removal mechanisms of typical PPCPs by GAC included GAC adsorptionand organic competition. Adsorption kinetics of typical PPCPs to GAC fittedexponential decay model. Adsorption coefficients （Kd） of the PPCPs were0.0067⁰.0133min^-1. Kdincreased with decreasing pH values, but decreased by20⁴7%in humic acid （HA） solution. Adsorption behaviors of the PPCPs wereinfluenced by their physiochemical properties and GAC structure characteristics.Population structure of microorganisms changed obviously under the typicalPPCPs stress, with a lot of opportunity bacteria detected.Removal mechanisms of typical PPCPs by UF included UF membraneadsorption and cooperative adsorption by HA or particles. The PPCPs removals by UF increased with decreasing pH values. HA and particles improved theremovals of the PPCPs by UF. The removals increased with increasingconcentration of HA and particles, but changed little with particle size. Organiccarbon partition coefficient （Koc） had an important influence on adsorptionbehaviors of typical PPCPs. The influence of acidity coefficient （pKa） wasrelated to the solution pH.The hybrid processes removed typical PPCPs by30¹00%, with75⁹0%ofthem removed by GAC. GAC adsorption and biodegradation accounted for94%and6%, respectively during GAC treatment. The removal efficiencies of thePPCPs were affected by PPCPs concentration in the influent, filtration velocity,pH, organic matter, GAC media height, GAC characteristic, membraneproperties and ozonation.The hybrid processes removed turbidity, particles, organic matter andmicroorganisms effectively. The height of GAC media layer and filtrationvelocity of GAC process had an important effect on the performance of GACprocess. UF performance was affected by water quality, operation parameters,membrane types and the changes of membrane properties. UF membrane foulingwas caused by organic matter, metal ions and microorganisms.