Effect Of Electrocatalytic Oxidation Pretreatment Technology On Ultrafiltration Membrane Fouling

The ultrafiltration?UF?technology plays an important role in the wastewater reuse process.The ultrafiltration technology has the advantages of good selectivity,high efficiency and wide application.However,membrane fouling is a major challenge in the application and diffusion of ultrafiltration membrane technology.Ultrafiltration membrane contamination can result in higher energy consumption,more frequent physical or chemical cleaning,and shorter membrane life.During the secondary effluent reuse of municipal wastewater treatment plants,it was found that dissolved organic matter?EfOM?in secondary biological treatment water is the main substance causing membrane fouling.An effective way to solve the membrane fouling caused by EfOM is to remove or convert it by pretreatment to achieve the purpose of reducing pollution.The main substances that cause membrane fouling in the secondary biological treatment effluent are:humus,polysaccharides and protein.The experiment firstly used humic acid,sodium alginate and bovine serum albumin to configure simulated wastewater for treatment.The effects of electrode spacing,electrode type and current density on the experimental treatment results in the electrocatalytic oxidation experiment were investigated.The experimental results show that all three organic pollutants cause serious membrane fouling problems.After pretreatment by electrocatalytic oxidation,the membrane fouling caused by sodium alginate and humic acid has a good alleviation effect,and there is obvious relief in membrane flux.However,electrocatalytic oxidation has a limited effect on protein-induced membrane fouling,and the DOC of protein-simulated wastewater has increased significantly.The electrocatalytic oxidation pretreatment effectively changed the structure and properties of the contaminants,reduced the concentration of simulated pollutants,and changed the way the membrane fouled.The experiment uses the actual secondary biological treatment effluent from the pollution treatment plant for membrane filtration experiments.The experiment first systematically analyzed the water quality of the secondary biological treatment effluent and carried out membrane filtration experiments.Secondly,the secondary effluent was treated by electrocatalytic oxidation pretreatment,and the influence of current density on membrane fouling was explored.By controlling the current,the purpose of better mitigating membrane fouling was achieved.The results showed that the electrocatalytic oxidation pretreatment experiment combined with DOC,UV₂₅₄,UV-Vis spectrum,three-position fluorescence spectrum,comparative molecular weight distribution and other detection methods showed that the content of typical pollutants in water was significantly reduced,and mainly Made up of small molecular weight substances.The organic matter on the surface of the membrane was effectively removed by Membrane Surface Morphology and Fourier Infrared.In this paper,the effects of electrocatalytic oxidation pretreatment on the mitigation of ultrafiltration membranes were analyzed from the perspectives of simulated wastewater and actual wastewater.The comparison of membrane flux and reversible pollution has a relatively straightforward judgment on electrocatalytic oxidation to reduce membrane fouling.The effluent water quality and the reasons for reducing membrane fouling were systematically analyzed.The membrane fouling,membrane fouling index and other models were used to discuss the possible degradation mechanism during membrane fouling.The research results can provide ideas for the ultrafiltration pretreatment water purification process.