(1) Product characteristics of fn215 filter material
Due to the fiber characteristics of glass fiber and the excellent properties of PTFE, fn215 filter material has the following product characteristics:
Feature 1: outstanding temperature resistance
Our company selects domestic alkali free glass fiber raw materials. The temperature resistance of alkali free glass fiber is above 260 ℃ and that of medium alkali glass fiber is only 220 ℃. The glass fiber filter material can operate continuously from above the acid dew point to 260 ℃. Fn215 filter material is baked in 280 ℃ oven for 2 hours, and its physical and chemical indexes and color remain unchanged, which is not available for other filter materials.
Feature 2: high strength, folding resistance
The warp and weft strength of fn215 woven filter material is not damaged by acupuncture, which is more than several times that of ordinary felt filter material. Due to its high strength, it can be processed into 10 meter or even 12 meter long filter bags for use; The filter bag will not shrink under high temperature, almost maintain the original size, will not affect the gap between the filter bag and the skeleton, and ensure the ash removal effect. The elongation of glass fiber filter bag is less than 8%. During the filtration operation, the self weight of filter material plus the weight of dust layer will not cause the elongation of filter bag. At the same time, it also greatly reduces the periodic damage of filter bag caused by pneumatic ash cleaning.
Fn215 woven filter material adopts monofilament with diameter of 3.8-5.0 μ M superfine glass fiber as raw material, the smaller the diameter of the single fiber of glass fiber, the better its folding resistance, and the longer the service life of the filter material.
We conclude through experiments that 5.0 μ The glass fiber of M is more than 9 μ The bending resistance of M glass fiber is 2.5 times higher (as shown in the figure below); And 3.8 μ The folding resistance of M glass fiber is 9 μ M is more than 5 times that of glass fiber. In other words, from the perspective of folding resistance, the diameter of monofilament is 3.8 μ And monofilament diameter 9 μ The service life of M glass fiber made into filter bags will differ by 15-20 times.
Feature 3: oxidation and corrosion resistance
At room temperature, fn215 woven filter material is resistant to the erosion of organic and inorganic acids and maintains good performance and stability in weak alkali. Through experimental test and analysis, the acid resistance of fn215 woven filter material developed by our company is many times higher than that of ordinary glass fiber filter material;
Fn215 woven filter material will not be oxidized by oxygen or nitride, so it is unnecessary to consider the problem of high and low oxygen content in the dust collector. Therefore, the oxidation resistance and corrosion resistance of glass fiber are outstanding, and the filter material is impregnated with PTFE lotion as a whole. PTFE lotion impregnation will form a dense protective film on the surface of glass fiber. Therefore, the fn215 woven filter material filter bag is subject to little erosion during the operation of dust removal equipment.
Feature 4: good waterproof
Our company's fn215 woven filter material adopts a unique process in the post-treatment mode. The produced fn215 woven filter material shows very good waterproof performance at room temperature and high temperature, which is more conducive to the application of fn215 woven filter material in cement working conditions. The waterproof property of the filter material is very good. The waterproof grade can reach grade 3.5 under normal temperature and grade 4 under high temperature.
The thickness of filter material is about 0.9mm, which is only 1 / 3 of felt filter material, and the texture is soft. During ash cleaning, the filter material shakes in a serpentine shape, and the dust is easy to peel off; Low ash cleaning pressure, less ash cleaning times and longer ash cleaning cycle can effectively reduce the consumption of compressed air, reduce the amount of maintenance and save the operation cost. The substrate of fn215 woven filter material is fn215 filter cloth with two-dimensional structure. Due to its structural characteristics, the operation resistance of the system is more stable than that of three-dimensional filter material.
Feature 5: easy ash removal and low resistance
In addition, due to the special self-cleaning and hydrophobic characteristics of PTFE (polytetrafluoroethylene), the filter material is easy to remove the dust, and the dust will not go deep into the filter material. Therefore, it can ensure the airflow flux without increasing the running resistance. It is an ideal high-temperature flue gas filter material.
The micropores on the surface of fn215 woven filter material are small and uniform (0.10-2.0 μ m) It can separate all the dust larger than the micropore diameter, which is different from the deep filtration mechanism of ordinary filter materials through the powder layer. The filter materials are mainly surface filtration through microporous membrane. The following figure is the schematic diagram of two different filtration mechanisms of ordinary filter material and filter material. It can be seen from the figure that the surface filtration mechanism of the filter material can intercept almost all the dust in the dusty air flow, so the filter material has very high filtration efficiency.
Feature 6: high filtering accuracy
To sum up, fn215 woven filter material vibrates in a serpentine shape during ash cleaning, and the dust is easy to peel off; The ash cleaning pressure is small and the ash cleaning times are few, which can effectively reduce the consumption of compressed air and save the operation cost. As long as it has ideal air distribution and reasonably designed ash cleaning system, the pressure difference of fn215 woven filter material is very stable during operation, and the system resistance increases very slowly after long-term operation.
The surface filtration of fn215 woven filter material has the following characteristics:
? improve the capture rate of fine dust and reduce dust emission;
? improve the ash removal capacity of filter bag, low resistance and low pressure difference;
It is durable and prolongs the service life of the filter bag;
? reduce fan energy consumption;
? increase ventilation;
? have the ability to overcome accidents and regenerate;
? reduce the accumulation of dust in the filter material, resulting in the blockage of the filter material.
(2) Fn215 is the key factor to achieve high filtering accuracy
V weft puffing, the key factor to achieve high filtration accuracy
Fn215 woven filter material weft is treated by a special bulking process. The fiber structure is more fluffy, the fabric structure is thicker, the fiber gap is more compact, the surface area is increased, the dust collection time is prolonged, and the fine dust is beneficial to agglomeration. The powder layer structure is fluffy, the porosity is large, the holes are more uniform, the dust removal effect is better, and the resistance is smaller. Weft yarn adopts expansion technology, which has the following characteristics compared with ordinary glass fiber filter material:
? under the same gram weight, the thickness of expanded yarn filter cloth is thicker;
The air permeability of expanded yarn filter cloth is better than that of ordinary filter cloth, and the uniformity is good;
? good filtration performance, loose yarn and large surface area, which is conducive to interception, diffusion, static electricity, gravity, inertia and other effects to capture dust;
After the post-treatment of bulky yarn filter cloth, the wetting agent is easy to "wrap" on the surface of a single fiber to form a protective film;
The expanded yarn filter cloth is conducive to the combination of substrate and film and improve the fastness.
V PTFE microporous membrane -- the key element to achieve high filtration accuracy
Our company adopts teflon resin imported from DuPont of the United States or Daikin of Japan. The produced ePTFE membrane has smooth surface, chemical resistance, uniform and small pore size, high porosity and uniform air permeability. Under the same air permeability, the membrane thickness value is large, with good wear resistance, long service life, high filtration efficiency and good fastness. It can withstand 8kg injection pressure without stripping the membrane. Through the application of actual working conditions, the stripping rate of microporous membrane is less than 5%.
The surface of the microporous membrane has spider network microporous structure, and the pore size of the microporous membrane is 0.1-2 μ M, thickness 15 μ M, porosity > 85%, up to 1 × 109/cm2。 The filter precision of fn215 woven filter material is high, which further ensures the realization of "ultra-low emission" standard of flue gas.
V key element to achieve ultra-low emission - filter bag sewing
The sewing of filter bag shall comply with relevant provisions of industrial standards HJ / t326-2006 and GB / T 12625. Cutting with CNC slitting machine, with stable size and no deviation; The sewing is controlled by continuous production line, and the product quality is better and more stable; The upper and lower pieces of the bag body stitch are flat, and the interface parts of the bag mouth and bag bottom are folded evenly. The bag body is sewn with high-strength PTFE thread or glass fiber thread to prevent thread opening caused by corrosion; Guide and manage each production process in strict accordance with the standards of ISO9001:2008 quality management system, and establish the concept of ***** quality management.