1. Polyphenylene sulfide (PPS)
PPS fibers can operate continuously at 190 ° C and can withstand temperatures of 232 ° C instantaneously (without the influence of other chemical components). When operating temperatures exceed 190 ° C, PPS fibers will undergo hydrolysis. Polyphenylene sulfide PPS has excellent acid and alkali resistance and is widely used in the treatment of combustion flue gas. In the early stage, polyphenylene sulfide PPS filter material is mainly used in industrial coal-fired boilers and carbon dioxide flue gas treatment. In some applications, due to chemical erosion, hydrolysis and other reasons, Aramid is not suitable for some applications, polyphenylene sulfide PPS fiber filter material can be used as a substitute, but when the oxygen content in the flue gas to be treated exceeds 10%, when the operating temperature exceeds 165 degrees, PPS will decompose.
2. Polyimide (P84)
(P84) polyimide fiber is a kind of flame retardant and temperature stable fiber, in the temperature condition of 240 degrees, (P84) polyimide fiber mechanical properties will not change, the highest temperature up to 260 degrees. (P84) fiber has no melting temperature and is naturally golden yellow. The fiber can be used as filter cloth and spinning filament yarn. (P84) polyimide is not a hygroscopic fiber filter material. (At 65% relative humidity, about 3% hair water absorption). In addition, the (P84) fibers is exception type (leaf surface) cross section structure, has large filtration area, has excellent filtering performance, so the (P84) fiber also was usually implanted filter material surface (side) to meet level to improve the filtration performance of filter material, (P84) material is mainly used in chemical conditions demanding applications (but should be covered for free acid conditions). There are examples in the application of drying, forging, smelting various industrial kilns, coal-fired boilers and garbage incinerators.
3. Glass fiber (GL)
Glass fiber can be used to make fiber weaving, glass expanded yarn weaving a needled felt. The highest continuous glass fiber filter material heat resistance up to 260 degrees, instant high temperature of 290 degrees, under the condition of high temperature of 260 degrees, the glass fiber filter material itself will not be damaged directly, but used to increase lubricity between glass fiber finishing material will evaporate, eventually leading to mechanical wear between the glass fiber, glass fiber filter material is flame retardant, Almost no moisture absorption (no hydrolysis), excellent dimensional stability and reasonable strength characteristics. Glass fiber fabric tensile strength is particularly good, but the flexural resistance is relatively weak, bending and friction should be avoided in disposal. Glass fiber filter material acid resistance is relatively good, but HF, concentrated sulfuric acid and hot phosphoric acid on glass fiber filter material corrosion, in high temperature state, weak alkali, anhydride, metal fluoride on glass fiber filter material will also have damage. Therefore, glass fiber filter material generally can not be applied at dew point temperature, glass fiber filter material is mostly used for carbon black industry, cement kiln, cement clinker cooling application. Iron and steel sintering process, industrial boiler, carbon dioxide industry and various waste incinerator application.
4. Polyacrylonitrile (DT)
Polypropylene wax synthetic fiber filter material has good hydrolysis resistance. Suitable for continuous operation temperature up to 125 degrees, instant can withstand 140 degrees. Polyacrylonitrile synthetic fiber filter material is used in non-ferrous metal processing, smelting process, in the production process of carbon black, cement, lime, fertilizer, coal drying process has been used; It is also widely used in the field of wet filtration. The overall performance of polyacrylonitrile fiber is better than that of polyacrylonitrile fiber filter material.
Polytetrafluoroethylene (PTFF) Teflon synthetic fiber is a unique material that can withstand acid and alkali attack in all PH values at 240 ° C continuous operating temperature and 260 ° C instantaneous operating temperature. Ptfe fiber has excellent self-moistening properties, no moisture absorption and can withstand ultraviolet radiation. But THE wear resistance of PTFE fiber is general, so the filter bag frame has strict requirements (finish). PTFE fiber filter material is more suitable for wear – resistant and corrosive harsh conditions, high service life of filter material occasions. PTFE fiber can also be mixed with glass fiber made of performance, the price is more reasonable filter material. Polytetrafluoroethylene synthetic fiber filter material can be used for coal-fired boilers, garbage incineration, carbon black production, white powder production and other process flue gas treatment, in the first smelting of some metals, refining and chemical production process also has the application of arylon.
The temperature range of Aramid fiber is 135-204 degrees, and it can withstand 220 degrees instantly. Aramid fiber can be made into continuous filament and fiber raw materials, used in the manufacture of needled felt or woven fabric filter material. The stability of Aramid fiber is excellent, the shrinkage rate is less than 1% at 177 degrees, and the Aramid fiber is easy to be hydrolyzed. Some acidic substances will accelerate hydrolysis, hydrolysis after the color of the filter material will become red brown. In the presence of Sox and moisture in the flue gas, or in the presence of frequent dew point phenomena, such as coal-fired boilers, or greatly shorten the service life of aramid fiber, although acid resistant treatment of aramid fiber can be carried out, it is recommended under acidic and humid conditions. Avoid aramid as much as possible.
Post time: Jul-11-2022