Reasons for the short service life of the dust bag
Burning: the main reason for the burning of the bag of the dust remover is that the initial layer thickness of the bag surface is not enough and the temperature of the flue gas is too high. If the temperature of the flue gas treated by the precipitator for a long time exceeds the working conditions of the bag, it is easy to make the bag harden and contract, or to melt and produce holes. If the initial layer thickness is not enough, the sparks in the flue gas flow in, or the dust heats up, the bag may also burn into holes. Causes the cloth bag to burn mainly manifests in the online new replacement cloth bag. Due to the lack of precoating after on-line replacement, the high temperature flue gas carrying Mars directly touches the cloth bag, which is easy to burn. Measures to prevent burning: ensure the initial layer thickness of the bag surface. Ensure that the exhaust gas temperature is not over temperature (#3, #4 furnace control standard is not higher than 180 ℃).
Abrasion: the abrasion cloth bag mainly occurs in the middle part of the dust remover, and on a single cloth bag, it mainly occurs within 1 meter from the cloth bag to the outlet. The main reasons are uneven distribution of flue gas, high flow velocity in the middle of single chamber, high filtration gas velocity at the outlet of a single cloth bag, resulting in dust impact, abrasion of cloth bag, damage to fabric fiber tension of cloth bag, easy to perforation of local cloth bag, and short service life. Replace the cloth bag on the frequently worn part with the wear-resistant cloth bag.
If the distance between bags is too small and the keel is bent, it is easy to cause wear between bags. The difference between the diameter of the cloth bag and the keel has a bad cleaning effect when it is too small, which will reduce the cleaning cycle and increase the pressure of the air jet. When it is too large, the friction between the cloth bag and the keel will accelerate the wear. Special attention should be paid to the fact that some filter cloths vary greatly with temperature and have the characteristics of elongation.
When there are holes or burrs in the keel welding, or the rough surface caused by corrosion, the wear of the cloth bag will also be accelerated. The cloth bag and the porous plate are not sealed tightly, which will cause the abrasion of the deconvolution at the top of the cloth bag.
The alignment of Venturi tube or pulse tube to the cloth bag is not correct, which is easy to cause abrasion of the upper part of the cloth bag caused by the air jet from the spray pipe. Too frequent cleaning of cloth bags will accelerate the wear of cloth bags.
Too high filtration gas speed will break the initial dust layer and cause excessive wear due to the impact of dust on the cloth bag. If the cloth bag is cleaned too many times at this time, the fabric of the cloth bag will be loose and the wear of the cloth bag will be accelerated. If the dust content in the flue gas exceeds the design standard, it will also accelerate the wear of the bag. Too much ash in the small ash hopper will cause too much dust in the flue gas chamber, which will also accelerate the wear of the cloth bag.
Measures to reduce wear: in the production process of the bag, the weak part of the bag shall be thickened. During the installation of the cloth bag, the cloth bag with too small distance and bent keel shall be adjusted and replaced. The matching between the cloth bag and the keel shall be appropriate (+ 10-20mm), and the length shall be the same. Keels shall be strictly inspected during use. Damaged keels are strictly prohibited. The sealing of the cloth bag and the porous plate shall be checked to ensure no leakage. The alignment of venturi and pulse tube is correct. In the process of operation, it is necessary to prevent factors such as too high filtering speed, too short cleaning cycle of cloth bag and too high pressure of compressed air injection. When setting the pulse cleaning cycle of the dust remover, it is better to ensure that the dust remover works under stable pressure and that the set pulse cleaning cycle time is the longest, the pulse cleaning time is to ensure that the initial dust does not fall off and the set time is the shortest. If the initial dust layer is insufficient, extended cleaning cycle can be used to supplement the reward. If differential pressure control is used, the stability of the inlet and outlet pressure setting of the precipitator can be improved.
