Study On Interception Of Membrane Oil In Wastewater By Silicon Carbide Ceramic Membrane And Membrane Fouling

The emulsified oil has stable physical and chemical properties,so the emulsified oil-containing wastewater becomes a difficult wastewater to be treated in the industry,and the conventional method is difficult to effectively remove,which poses a great challenge to the treatment of the oily wastewater.The ceramic membrane ultrafiltration technology has a good effect on the retention of emulsified oil.In particular,silicon carbide(SiC)ceramic membrane has become a research hotspot in recent years due to its high processing efficiency and small membrane fouling,and has broad application prospects.In this study,the SiC ceramic membrane was used as the material to separate the emulsified oil wastewater that is difficult to handle in the project.The specific research is as follows:A Laboratory simulated oil-in-water(O/W)emulsified oil wastewater was developed using a mixture of diesel or engine base oils and different types of surfactants(cationic surfactant CTAB,anionic surfactant SDBS and nonionic surfactant Tween 80).The oil droplet size and zeta potential of the emulsified oil in emulsified oil wastewater prepared by different concentrations of surfactant(0.25 CMC-2 CMC)were studied respectively.It was found that the emulsified oil wastewater prepared by cationic surfactant(CTAB)was emulsified.The oil is positively charged,while the emulsified oil in the emulsified oil wastewater produced by the anionic surfactant(SDBS)and the nonionic surfactant(Tween 80)surfactant is negatively charged.Further,it has been found that the emulsified oil in the emulsified oil-containing wastewater produced by the anionic surfactant(SDBS)has a smaller particle diameter.By studying the silicon carbide ceramic membrane to filter the COD and oil retention rate of the emulsified oil wastewater stabilized by different surfactants,the COD removal rate can be reached for different emulsified oil wastewaters stabilized by three kinds of surfactants.More than 86%;for emulsified oil wastewater with different surfactants,the oil retention rate can be close to 92%,with high retention efficiency,and for anionic surfactants(SDBS)and cationic surfactants(CTAB))Stable emulsified oil-containing wastewater,the oil retention will increase slightly as the concentration of surfactant increases.When the ceramic membrane filter non-ionic surfactant(Tween 80)stabilizes the emulsified oil-containing wastewater,the oil retention will first decrease and then rise as the concentration of the surfactant increases.When the concentration of the surfactant is high,the retention rate of the oil containing the emulsified oil wastewater stabilized by the silicon carbide ceramic membrane filtration cationic surfactant(CTAB)is the highest.By investigating the permeation flux of emulsified oil wastewater stabilized by different surfactants under four pressures(0.1Mpa-0.4Mpa)by studying the silicon carbide ceramic membrane,it was found that when the surfactants were the same,the emulsified oil wastewater was infiltrated.The flux decreases with the increase of surfactant concentration;through the adsorption model and classical plugging model analysis,when the SiC ceramic membrane filters three kinds of wastewater containing emulsified oil,it can be clearly found that when filtering cationic surfactant(CTAB)When the stable emulsified oil wastewater is used,the membrane fouling coefficient and the adsorption constant of the surfactant on the membrane are the largest.The results show that when the SiC ceramic membrane filters the cationic surfactant(CTAB)stable emulsified oil wastewater,Its membrane fouling is the most serious.