What are the types of dust filter bag filter materials?

Fiber filter. Fiber filter media has always occupied most of the filter media market due to its large surface area, fluffy volume, low price, and easy processing. Among them, non-woven fiber materials have the characteristics of short cloth-forming process, low cost and good filtration performance. , has become the leading product of air filter materials. Composite filter material. The so-called composite filter material is a filter material formed by intertwining different fibers to overcome the performance defects of a single filter material. It has been widely used in flue gas treatment in metallurgy, cement and other industries. Functional filter material. Functional filter materials are air filter materials developed for specific industries (such as high temperature resistance, corrosion resistance, antistatic, water repellency, oil repellency, flame retardant, removal of harmful gases, etc.), and are increasingly used in industrial flue gas Treatment, indoor air purification and other fields. 1. Fiber filter material The main raw materials of fiber filter material are polyester, polypropylene, nylon and many high temperature resistant chemical fiber filter materials such as Nomex, Procon, Torcon, Basfil, P84, etc. [2], as well as inorganic fibers such as glass fiber, ceramic fiber, metal fibers, etc. At present, my country's chemical fiber filter materials are mainly polyester woven fabrics and polyester needled felt polyester. Polyester has the advantages of good folding resistance and wear resistance, and can withstand the operating temperature of 135 °C under dry conditions, but continuously above 135 °C Work will become hard, faded, brittle, and short-term high temperature will also weaken its strength, so polyester has poor high temperature resistance, low strength, and high elongation. It is not suitable for use in high alkali and high humidity conditions. . In order to solve these problems, some researchers have developed a filter material interwoven with polyester and glass fibers. The filter material interwoven with fibers with different properties can take advantage of strengths and avoid weaknesses and exert their respective advantages. Glass fiber has the advantages of good high temperature resistance, low elongation, high strength, and good corrosion resistance, but at the same time, due to the smooth surface of the fiber, the small diameter and the small filtration resistance, the filtration efficiency is high. However, glass fiber has poor folding resistance and wear resistance, and is easily worn and broken due to frequent cleaning during use, which affects the service life. The filter material interwoven with polyester and glass fiber has good performance and has been used at present. The weaving methods of fiber filter materials are woven, knitted and non-woven. Because the fibers of woven and knitted fabrics form regularly arranged yarns, the yarns are closely intertwined with each other, and the fibers lack the possibility of forming a labyrinthine system. The fiber labyrinth type system can strengthen the dispersion effect, so that the particle suspension phase to be separated has more opportunities to collide and adhere to the single fiber, so the filtration efficiency of non-woven fabrics is significantly higher than that of woven fabrics and knitted fabrics, and also The flow rate of the carrier phase can be increased, i.e., the filtration process can be accelerated. At present, non-woven products have become the leading products of air filter materials. 2. Composite filter material Composite filter material is a hot spot emerging in recent years. For example, the strength of the spunbond nonwoven fabric is strong, but its uniformity is poor. The composite filter material formed by stacking it with the meltblown nonwoven fabric can not only overcome the disadvantage of the low strength of the meltblown nonwoven fabric, but also give full play to the advantages of the meltblown nonwoven fabric. The woven fabric has the characteristics of excellent filtration performance. SMS composite filter material is made by thermal bonding of spunbond, meltblown and spunbond three-layer non-woven fabrics under the action of certain temperature and pressure. The membrane composite filter material successfully developed in the mid-1990s is to cover PTFE on the woven cloth, non-woven cloth or glass fiber filter material. It has high filtration efficiency (over 9919% for submicron dust), low resistance (30%~40% lower than traditional filter media), long service life (up to 2~5 times that of traditional filter media), With the advantages of high temperature resistance (up to 280 e ) and high dust peeling rate, it has been widely used in dust purification and air conditioning filtration industries. 3. Functional filter material 1. High temperature and ultra-high temperature filter material. Mainly used in the treatment of industrial waste gas and dust such as iron and steel, power stations and incineration, mainly including polyphenylene sulfide chemical fiber Ryton filter material and imide amide chemical fiber Nomex filter material, polyphthalimide fiber P84, polytetrafluoroethylene Ethylene Teflon, some metal and ceramic filter materials have also been put into use in recent years. The metal sintered filter material made of metal fiber cotton mesh sintered at high temperature is used under dry smoke conditions, and the highest temperature is 600 ℃. 2. Corrosion-resistant filter material. The needle-punched sticky filter material made of polyphenylene sulfide fiber has strong normal temperature, high temperature acid resistance and normal temperature alkali resistance. Ideal filter material for gas. Glass fibers are also surface-treated to resist various aggressive media. 3. Antistatic filter material and flame retardant filter material. Used to collect industrial dust (such as face dust, chemical dust, coal dust), usually with antistatic agents and conductive fibers (such as metal wire, carbon fiber, polyester,Acrylic fiber) two methods to eliminate the static electricity of the filter material. Flame retardant fiber is a filter material with good flame retardant properties made of flame retardant fiber. 4. Water and oil repellent filter material. By performing water and oil repellent finishing on ordinary filter materials, the filter materials have the characteristics of water and oil repellency. There are two main finishing methods: (1) Reaction method, which causes the water repellent oil agent to interact with some groups in the macromolecular structure of the fiber. The reaction forms macromolecular chains, changes the affinity of fibers with water and oil, and becomes water- and oil-repellent. (2) Coating method: Use the coating method to prevent the filter material from being wetted by water or oil. The membrane filter material and the waterproof treatment on the surface of the filter material have achieved obvious results in solving the problems of anti-condensation and bag sticking.​​