The filter media is the core product of the filter bag of the baghouse, so the filter material should have the characteristics of high filtration efficiency, long service life and stable dust filtration performance. The commonly used processing methods of filter media are organic weaving, needlepunching and spunlace, and post-processing includes heat setting, impregnation coating, lamination, etc. There are generally the following types of filter media, namely woven fabric, needle felt filter material, spunlace filter material, island fiber filter material and coated filter material.
1. Woven fabrics
Woven fabric is a woven filter material made of satin weaving, according to different filtration requirements can choose different specifications of fiber, short fiber filtration performance is better, medium and long fiber is conducive to ash cleaning. Woven fabric filter media has excellent mechanical properties and compactness.
2. Needle felt filter material
The needle felt filter material is prepared from staple fibers into a net, laid into two layers, the base cloth is added in the middle, reinforced by acupuncture, and then prepared by post-treatment such as singeing, calendering, and heat setting. The needle felt fiber has a messy three-dimensional structure, which has a high filtration effect on dust and good air permeability, and is easy to clean and has a good ash cleaning effect.
3. Spunlace filter material
Acupuncture may damage the base cloth and fibers, so the preparation of spunlace media with a smaller diameter spunlace results in a smoother surface and improved filtration performance. After the aramid fiber is opened and mixed, the net is woven into a composite web by a lapper and an unwinding machine, the composite fiber web is reinforced with a pre-needle loom machine, and then the fiber web is further strengthened by hydroentanglement to obtain a filter material felt, and the filter material is processed by a roll after impregnating the filter material with a finishing agent. The spunlace filter material of the spunbond base cloth is made into the upper non-woven fabric, the first adhesive layer and other structures, and the non-woven fabric and the spunbond fabric are bonded by the pulp point method and cured at high temperature to obtain the spunlace filter material with better surface surface filtration performance and strength.
4. Island fiber filter material
Because microfiber has the effect of improving and improving the filtration performance of the filter material, the filter material made of the filter material, which is typical of microfiber, has a great improvement in filtration accuracy and filtration efficiency compared with the filter media made of traditional materials. PTFE filament and PPS/PET island composite fibers were used to make a composite filter material with 99.99% filtration efficiency for PM2.5 through acupuncture and alkali treatment. The island composite fiber mesh was made into the upper and lower layers of the island composite fiber filter material, and the polyester fiber web and polyester base were arranged in the middle of the fiber web to obtain an island-type composite fiber filter material, which had a smooth surface and higher filtration and interception efficiency.
5. Coated filter material
The coated filter material is prepared by the coating process, and the substrate is covered with a dust-proof layer by hot melt or adhesive. Due to the good compactness, the coated filter material can block the fine dust particles on the surface of the filter material and improve the filtration efficiency. However, the film is fragile and easy to break, so it should be operated with caution in the process of installation and cleaning.