Study On The Preparation And Performance Of High Efficiency Air Filter

Air quality is a focus of discussion,which is closely related to human health.The fine particulate matter suspended in the air seriously affects the air quality.Its existence makes people suffer from respiratory diseases.Therefore,how to filter out the fine particulate matter in the air is particularly important.The essential function of air filter is to purify air.The filter efficiency and filter resistance are its basic indexes,which have a great impact on the quality of the filter.This topic discuss the influence of melt-blown material,composite technology and the fabrication of air filter element on the filtration performance of air filter,so as to help enterprises produce high-quality and high-efficiency filters.In this paper,three kinds of melt-blown fabrics with different surface densities were tested.The results show that with the increase of the surface density of melt spray,the filtration efficiency and resistance of the sample will increase significantly.The bigger the diameter of particle is,the better the filtration performance of the sample is.When the particle size is small,the difference of filtration efficiency between samples with different surface densities is large;with the increase of particle size,the difference becomes smaller and smaller.Secondly,the melt-blown fabric with a surface density of 20g/m²was selected for the composite experiment,and the four factors of composite speed,composite pressure,melt-blown fabric tension and spunbonded fabric tension were changed during the experiment.The trend of the influence of composite process parameters on sample filtration efficiency and resistance was discussed.Then,the composite process parameters with maximum filtration efficiency were analyzed by orthogonal experiment.The experimental results show that the filtration efficiency and resistance of spunbonded fabric decrease with the increase of tension or compounding speed.With the increase of composite pressure,the surface density and thickness of the sample decrease,and the filtration efficiency and resistance decrease first and then increase.Among the four factors,the composite pressure has the greatest influence on the filtration resistance of the product,followed by the composite speed,melt blown fabric tension and spunbonded fabric tension.When the composite process parameters are spunbonded fabric tension 33N,composite speed 40m·min^-1,composite pressure 0.44MPa and melt-blown fabric tension 1.4N,the composite filter sample with the lowest filtration resistance is obtained.Finally,three different raw materials are made into filters.In the process of production,folding height and distance are changed.Different filters were studied from the filtration resistance,the filtration efficiency of particles with diameter（≥0.5μm）,the filtration efficiency of various particles with different diameters and the capacity of dust,and the effect of manufacturing process on the filter performance was discussed.Through the orthogonal experiment of the preparation of the filter,a high efficiency air filter with high filtration efficiency and the lowest filtration resistance was obtained.The experimental results show that with the increase of folding height and folding distance,the resistance of the filter and the filtration efficiency of particles with diameter greater than or equal to 0.5μm increase first and then decrease.The dust capacity increases first and then decreases with the increase of folding height and distance.The optimum composite filter material sample has the lowest resistance of 28.5Pa.The filter efficiency of the optimized composite filter material sample is similar to that of the factory control sample.When the parameters are set as folding height of 33mm,folding distance of 4.5mm and the raw material is the optimized composite sample,the filter efficiency meets the requirements of high efficiency filter,and the filter resistance is the lowest,which improves the competitiveness of enterprise products.Based on the analysis of the properties of composite materials and filter samples,the composite process and parameters of melt-blown materials,the preparation process and parameters of filters are described and discussed in detail,which has a certain reference significance for the preparation of high efficiency filters.