Study On Finishing Of High Temperature Resistance Spunlaced Filtration Materials

High temperature resistance nonwoven filter materials are widely used in the field of high-temperature dust removing. Under certain condition, water vapor condensation occurs in the filter materials, and there is oily substances existing under some working condition. Neither the presence of water or oily substances, which can cause blockage, soil hardening and other problems in the filter bags, and finally lead to more difficulties during the dust removing and increased pressure of dust removal system. Therefore, the water and oil repellency finishing must be carried on the filter materials.In this subject, PPS, P84and Nomex fibers were selected as raw materials. Through pre-entanglement of needle-punching and spunlaced reinforce process, nonwoven filtration materials with performance of high strength and low elongation were produced. Then, through the finishing process with PTFE finishing agent, high temperature nonwoven filtration materials with excellent oil repellency performance were obtained. Meanwhile, other performances of the final products were also studied. Besides, actual working condition were simulated, and further studies on the instantaneous temperature performance of PPS, P84were conducted, which will improve the anti-condensation performance evaluation system for filter materials. As conclusions have been made as follows:(1) Three kinds of high performance fiber including PPS, P84and Nomex were used as raw materials, through the process of spunlaced primary reinforcement, high temperature resistance filtration material with high strength and low elongation can be produced. Folds generated in the spunlace process was beneficial to the formation of Lotus Leaf effect during later water and oil repellency finishing.(2) PTFE-centered emulsion was used as finishing agent during the process of water and oil repellency finishing. After finishing, the filter materials which had poor water and oil repellency original had achieved at grade8of water repellency, grade7of oil repellency, and grade4of spray rinsing.(3) Actual working condition was simulated, and instantaneous temperature treatments were carried on experimental filter materials. The water and oil repellency of PPS and P84filter materials had been reduced, but which can still meet the standard requirements and demands of industrial and mining condition. In addition, the actual prerequisites must be met when using filter material:PPS instantaneous temperature was below230℃, and P84instantaneous temperature260℃.(4) It can be proved by experimental results that the water and oil repellency performance of high temperature filter materials through finishing process using PTFE emulsion was significantly increased. Filter materials produced in this subject could comply with the requirements of national standard.Study on the development of high temperature filtration materials with high water and oil repellency has theoretical meaning and practical values on guidance of production.