Common causes of damage to filter bags in use
1, improper installation of filter bag filter:
A. The installation process is chaotic. The storage of bag cages and filter bags is irregular. As a result, the filter bags or bag cages are deformed by extrusion.
B. The non-perpendicularity of the filter bag will cause long-term friction between the filter bag and the filter bag, between the filter bag and the wall plate, resulting in damage of the filter bag; C. Blowpipe deflection, blowing air pressure too high or blowing frequency is too high, easy Causes the bag mouth to be damaged and even separates the bag head from the bag body.
2, equipment is not well-made:
A, bag cage processing is rough, if there is rust, welding burr, burrs, open welding and other phenomena, will accelerate the mechanical wear of the filter bag;
B. The deformation of the board does not meet the requirement of flatness of 2/1000, and even distorts the unevenness. As a result, the verticality of the bag cage cannot be guaranteed, and the bottom of the filter bag will collide with each other. The elastic steel ring is also easily damaged, so that the installation and sealing of the filter bag can not be guaranteed, thereby forming air leakage and filter bag damage;
C. There is a deviation in the flower board hole. When the board also shows a deviation of 2-3mm, the filter bag cannot be installed in place. This will cause the filter bag to be ashed or the filter bag and the flower board hole fall off, which will cause the bag filter to fail to operate.
3, temperature instability of dust removal equipment:
A. The higher the temperature of the flue gas, the faster the chemical reaction, and the filter materials that are sensitive to oxidation and other chemical reactions are easily damaged under such operating conditions, leading to a significant reduction in their service life.
B. When the dust removal equipment is in operation, it must always maintain the temperature above the knot. If the temperature is lower than this limit, the moisture in the flue gas will be concentrated, and the concentrated water vapor will be mixed with the dirty smoke, which may produce corrosiveness. Acid dew, corrosion of filter bags or paste bags, resulting in shortened filter bag life or increased dust removal equipment operating resistance, severe dust will make it impossible to run.
C. The effect of dust removal temperature and the presence of sparks in the flue gas tend to burn the filter bag.
4, filter material material choice is not reasonable:
A. Commonly used polyester filters and aramid filters are the most prone to hydrolysis reactions. The higher the moisture content and temperature in the gas, the faster the damage caused by the hydrolysis, and the more moisture or moisture in the air. In this case, it is not appropriate to use such filter materials; B. The commonly used polypropylene filter media and polyphenylene sulfide filter media are easily oxidized. Therefore, in the working conditions with oxygen content exceeding 15%, such filter media should not be used.
C, glass fiber filter if used in the dust purification environment containing fluorine flue gas, the damage is faster.
Some suggestions and measures to prevent breakage of filter bags
A. The number of skeleton reinforcing bars should be reasonably matched according to the material of the filter material, and it should be smooth, smooth and hairless, with sufficient strength, verticality up to the industry standard, and well matched with the filter bag.
B, flower board leveling, flower board hole surface is smooth, flower board hole from the box wall, flower board hole between a larger safety distance, in order to prevent flower board error, frame tilt, resulting in collision between the filter bag Filter bag wear.
C, pulse nozzle should ensure vertical, and should be concentric with the flower board hole, the error is less than 2mm.
D. The arrangement of pulse nozzles has an important influence on the pulse dust removal of the bag filter. The pulse nozzle has an optimal distance from the filter bag mouth. When it is too small, the induced air flow is insufficient, and the upper bag mouth of the filter bag is easily damaged; when it is too large The pressure attenuation of the pulsed air flow is too large, which is not conducive to the flow of air into the bag. The specific pulse distance is related to the diameter of the pulse jet, pulse air flow parameters, and the diameter of the bag. It is necessary to ensure that the pulse air flow and induced air volume are greater than the volume of the filter bag.
E. The air distributor of the dust collector needs to set the air distribution plate so that the air distribution of each box is relatively uniform. The position and quantity of the air distribution plate have a great influence on the air distribution.
F, there should be a certain safety distance between the bottom of the filter bag and the ash hopper. There should be a high and low material level meter in the ash hopper. When there is too much ash in the ash hopper, the ash should be unloaded in time.
G. Before installing the filter bag, the site shall be clean, the structure of the filter bag skeleton blowing pipe and other facilities shall be arranged in order, the impurities in the dust removal device shall be cleaned up, the installation process shall be well-organized, and there shall be no cross-operation affecting the filter installation.
H. To eliminate possible sparks in the flue gas, the most effective preventive measure is to install a spark trap before the flue gas enters the dust collector and remove the spark from the flue gas.
I. Influenced by regional climate differences, it is required that the dust collector be better sealed and the cabinets be kept warm to prevent local condensation of the dust removal equipment.
J. After the filter bag is installed and the dust removal equipment is in operation, the filter bag should be pre-sprayed with lime powder and talcum powder. The effect of the use of the filter bag is not only related to the quality of the filter bag itself, but also related to the reasonable design of the filter, and the installation, operation and maintenance of the filter bag.