Preparation Of Biomimetic Fiber Materials Based On Electrospinning Technology And Research On Gas-liquid Filtration Performance

Impurities such as lubricating oil and water are often entrained in the process of natural gas purification and transportation.If not removed,it will affect the gas quality and reduce the service life of the equipment.Coalescing filtration is a method commonly used to remove the above-mentioned liquid impurities,but currently has the disadvantage of large filtration resistance.To this end,this thesis uses glass fiber material as the base material to analyze the influence of its wettability on the filtration performance of the composite filter material after added nanofiber membranes with different components.We carry out bionic fiber composite on the optimized substrate,and investigate the influence of operating conditions and liquid properties on the filtration performance of the filter media before and after the composite.Nanofibers with different compositions are prepared by uniaxial electrospinning technology,and the sandwich structure composite filter material of“glass fiber material+nano fiber+glass fiber material”;spider silk biomimetic is prepared by coaxial electrospinning technology fiber,and combine glass fiber material to form a sandwich structure composite filter material of“glass fiber material+bionic fiber+felt drainage layer”.The results show that the microscopic morphology of bionic fibers is coupled by multiple preparation conditions.When the concentration of polystyrene solution is 25%,the concentration of polyethylene glycol solution is 20%,the spinning voltage is 14k V,and the relative humidity is 12%,the microscopic morphology of the biomimetic fibers is optimal.The above composite filter materials are tested with the filter material filtration performance testing system.The results show that the effect of nanofiber membrane on the filtration performance of the composite filter material is mainly determined by the wettability of the substrate on the leeward side,and it has nothing to do with the wettability of the substrate on the windward side.When the substrate on the leeward side is lipophilic,the addition of nanofiber membranes with different components can improve the comprehensive filtration performance of glass fiber materials,while it is the opposite when oil is drained,which indicates that the substrate on the leeward side of composite filter materials should choose lipophilic glass fiber.The filtration performance parameters of bionic and traditional composite filter media have the same dependence on operating conditions and liquid physical parameters,and they are not changed by adding bionic fibers.However,the directional transport and liquid collection function of the biomimetic fibers will change the process pressure drop curve of the traditional composite filter material,reducing the steady-state pressure drop by about 25%,and is basically not affected by changes in apparent gas velocity or liquid loading rate;The APS state quality factor is increased by about 0.4k Pa^-1（about 30%）,and reducing the apparent gas velocity and increasing the liquid loading rate are conducive to improving the comprehensive filtration performance of the composite filter material.However,the directional transport and collection function of biomimetic fiber is selective,which can be used for dioctyl sebacate and triethylene glycol,but not for dimethyl silicone oil and engine oil.Finally,the comprehensive filtration performance of biomimetic composite filter material decreases,and the greater the liquid viscosity or the smaller the surface tension,the more obvious the reduction of comprehensive filtration performance.The research results can provide a theoretical basis for the selection of substrates for composite filter materials,and provide theoretical support and technical guidance for the development and engineering applications of new composite filter materials with low filtration resistance.