Experimental Research On Recovery Of Waste Aramid Filter Material

The bag filter has the advantages of high dust removal efficiency and strong adaptability,and is widely used in the field of dust removal.The core of the bag filter is the filter bag.During use,the processing gas and its own wear will adversely affect the life of the filter bag.On average,it needs to be replaced every 3-4 years.A large number of waste filter materials not only cause secondary pollution,but also cause waste of resources,especially for aramid filter materials with excellent performance and high manufacturing cost.Therefore,how to recycle waste meta-aramid filter materials with high quality has become a major issue in the current industry,and it is of great practical significance to carry out experimental research on this.In this paper,on the basis of analyzing the characteristics of meta-aramid fiber and studying the theory of polymer dissolution,N,N-dimethylacetamide(DMAc)solution is selected as the organic solvent to dissolve the waste aramid filter material,lithium chloride(LiCl)and calcium chloride(CaCl2)as the dissolving co-solvent,designed and constructed specific experimental programs and devices,and studied the influence of temperature,solute-solvent-cosolvent mass ratio on the dissolution rate of waste aramid filter media and the recovery process.Through the comparative analysis of the dissolution process and the dissolution law of meta-aramid in the DMAc/LiCl and DMAc/CaCl2 dissolution systems,it can be seen that the cosolvent LiCl has a better dissolving effect on the waste aramid fiber than CaCl2;then the LiCl is further analyzed as the best dissolution conditions of the cosolvent.The experimental results show that when the LiCl concentration is 4wt%and the dissolution temperature is 110℃ the dissolution is the best,and it can dissolve up to 20wt%of the meta-aramid filter material.The experiment was extended to a reactor.At a temperature of 110℃ and a LiCl concentration of 4wt%,25wt%of the aramid filter material can be dissolved.This article further studies the method of using recycled aramid solution to make products.A stable and uniform aramid film was prepared from the aramid solution by the NIPS method.The tensile strength can reach 11.76MPa,and the film has relatively good insulation.The average value of the resistivity is 1.525×1013Ω·m.The meta-aramid nanofiber membrane is prepared by the electrospinning method,and the fiber diameter is 50-100nm.The research results show that the reuse method can effectively realize the recycling and reuse of aramid fiber.The research results of this paper fill the gap in the recycling of waste aramid filter materials,and have direct guiding significance for the recycling of waste aramid filter bags in the industry.