Effect Of Three Model Fouling Compounds On UF Membrane Fouling

Water shortages and pollution are the greatest threats that we are facing with,particularly, water pollution problems is the most pressing problem that we need toresolve right now. However, the types of pollutants are increasing rapidly, and theremoval of disinfection byproducts is difficult, while drinking water quality standardsbecomes more and more stringent. Against this background, the water treatmenttechnology of ultrafiltration membrane stands out, but the membrane fouling hinders itsextensive application. Based on previous studies, this study uses humic acid(HA),sodium alginate(SA) and bovine serum albumin(BSA) to simulate the effects of humus,polysaccharides and proteins on membrane fouling. This research only studies theeffects of the concentration of pollutants, solution conditions and the admixture ofdifferent pollutants on the reversibility and resistance of membrane fouling and fluxdecline without considering the influences of particles, turbidity and metal ions. Flatultrafiltration membrane was used in this research.The experiment of single pollutant’s effects on ultrafiltration membraneinvestigated the retention rate and concentration of HA, SA, BSA after treatment withUF, and how the changes of solution conditions impact flux decline and the reversibilityand resistance of pollution on UF.Experimental results show that: the UF membrane hashigh retention rates of HA, SA and BSA; Increasing concentration of HA, SA, and BSAcan aggravates the pollution of ultrafiltration membranes, high concentration ofpollutants can form thick cake layer on the surface of membrane and increase thepollutants which adsorbed by membrane’s internal pore; HA, BSA major causesirreversible pollution, SA mainly causes irreversible contamination; with the increasingof the pH and the concentration of Ca2+, the membrane fouling which is caused by HA,SA, BSA reduces; Na+concentration increased so HA, BSA weaken pollution caused byultrafiltration membrane fouling caused so SA increases. When the concentration ofNa+increases, the membrane fouling caused by HA and BSA increases, while thefouling caused by SAdecreases.The effect of the coexistence of multiple pollutants on ultrafiltration membranefouling was also studied in this research. The results show that: the membrane foulingcaused by the coexistence of HA and SA is between the fouling caused by singlepollutant. When HA exists, irreversible fouling caused by two pollutants aggravates;The coexistence of HA and BSA mitigates membrane fouling; With periodic increasing,SA and BSA mixed membrane fouling caused by the mixed solution of SA and BSAincreases; the mixed solution of HA, SA and BSA can reduce membrane fouling, theexistence of SAincreases the proportion of reversible fouling.In this paper, a systematic study of how single HA, SA and BSA and the mixed solution of them effect ultrafiltration membrane fouling has been done respectively, sothat it can spread the application of ultrafiltration membrane technology and guide thestudy of membrane fouling.