Dust Filter Bags Material Filter Cloth

Needle felt filter materials are mainly used in pulse dust-cleaning bag filter, and woven filter cloth is mainly used in blow-back large bag filter.

In the flue gas filtration and purification, the material of the filter bag is generally determined by the flue gas temperature. Select appropriate fibers to first make needle felt or woven cloth, and then further process them into filter bags.

(1) Medium and low temperature section (90℃~140℃)

Applicable fiber polyester (PET) fiber and homopolyacrylonitrile (PAN ACRYLIC) fiber, etc.

(2) Medium and high temperature section (140℃~200℃)

Applicable fibers include Nomex, Polyphenylene Sulfide (PPS), etc.

(3) High temperature section (200℃~300℃)

Applicable fibers include P84, polytetrafluoroethylene (PTFE) and glass fiber (FIBERGLASS).

1, homopolyacrylonitrile fiber

When the temperature of  homopolyacrylonitrile fiber is lower than 125℃, the fiber has good resistance to organic solvents, oxidants, inorganic acids and organic acids. Homo-polyacrylonitrile will not be hydrolyzed, so it can be used to replace polyester fiber in low temperature, chemically corroded and humid occasions.

2, PPS fiber

PPS fiber is a high temperature resistant synthetic fiber. The simple chemical structure of PPS determines its good temperature resistance and chemical stability. Each aromatic ring interacts with a corresponding sulfur atom, and this structure has extremely high stability. Since the geometry of PPS is symmetrical with each other and has a high degree of linearity, the result is that PPS can crystallize easily and very quickly, can reach extremely high crystallinity, and show a very high melting point (285°C), which is excellent The heat resistance. In addition, PPS fiber has excellent flame retardancy, chemical resistance, and dimensional stability, and has various characteristics as a high-performance fiber. PPS fiber can continuously withstand the temperature of 190℃, and resist the chemical corrosion of a variety of acids, alkalis and oxidants. The most important thing is that PPS fiber will not be hydrolyzed, so it can replace Nomex fiber and run at high temperature under humid conditions with chemicals (such as sulfur dioxide). Typical applications are pulse bag filters used in utility boilers, coal-fired boilers, and cogeneration boilers. PPS fibers can also be used to replace other synthetic fibers that cannot withstand high temperatures or contain chemicals and are not resistant to moisture.

3, P84 fiber

P84 is a kind of high temperature resistant synthetic fiber, which can be continuously exposed to 240℃ environment. P84 is made of a polycondensation polymer, which is not resistant to hydrolysis. The cross-section of P84 is in the shape of a three-leaf lobe. Due to the increased surface area of the single fiber, it can effectively trap particles. P84 is a non-thermoplastic fiber, and its abrasion resistance to pulse cleaning is stronger than that of glass fiber. Therefore, P84 can be used to replace glass fiber under conditions that require good abrasion resistance. P84 works best in an environment without chemicals or moisture, while P84 is easily corroded in an acid-base environment.

4, PTFE fiber

Until now, PTFE fiber is still the best chemical resistant fiber found in the world, with a melting point of 327°C and an instantaneous temperature resistance of 300°C. PTFE fiber has good friction resistance, non-combustibility, insulation and heat insulation, and can withstand the oxidation corrosion of various strong oxides without hydrolysis. PTFE fiber is widely used in waste incineration and dust removal, and will be widely used in dust removal conditions of burning high-sulfur coal in the future. PTFE filter material has high filtration efficiency and good dust removal performance, even in the case of high temperature, only a small amount of dust adheres to the surface. Under the same working conditions, the service life of PTFE filter material is more than 1 to 3 times longer than that of other materials, and it has a very high cost performance.

5. Glass fiber has outstanding high temperature resistance and can be continuously exposed to the environment of 260℃; it can withstand the corrosion of most acids (except hydrofluoric acid), but strong alkali at room temperature and moderate alkali at high temperature will corrode the glass fiber. The glass fiber has very poor resistance to flexure and abrasion, and it is quickly damaged during pulse cleaning or violent cleaning. The brittleness of glass fiber fabrics makes it only a good candidate filter material for blowback cleaning systems, and cannot be used in oscillating or impulsive systems. However, because of its low price, when users require low prices, dust removal equipment manufacturers also use glass fiber as pulse bag filters. Glass fiber fabrics are generally used only to reduce costs and when working at high temperatures.