Bag filter filter bag blockage and coping method thereof

The main reason for the clogging of the filter bag of the bag filter is that the filtration speed is too high, the dust is too fine, the dust is sticky, the filter bag is poorly cleaned, the filter bag is stuck, condensation, and knot. If the design standard of the filter wind speed ultra-filter bag operated by the precipitator is very easy to cause the fine dust in the flue gas to enter the inside of the filter bag fiber, the filter bag blockage resistance increases. It is a good method to use a membrane filter, a coating filter or a pre-ashing treatment on the surface of the filter bag. For viscous dust, it is necessary to reduce the filtration wind speed, or increase the pressure of pulse injection, or use the offline pulse cleaning filter bag, but the better method is to increase the filtration area, reduce the filtration wind speed, and extend the filter bag. Service life.

Poor cleaning of the filter bag mainly includes frequent cleaning and excessively long cleaning time. If the number of cleaning times is too high and the cleaning pressure is too large, the fiber structure of the filter bag is loosened to increase the fine dust in the flue gas to block the filter bag. If the cleaning time is too long, the initial powder layer on the surface of the filter bag will be washed away, resulting in a decrease in the filtration accuracy of the filter bag. If the cleaning time is too short, the dust on the surface of the filter bag is not completely cleaned, and then the filtration starts. The dust gradually accumulates on the surface of the filter bag, causing the filter bag to clog. In solving this problem, it can be passed several times. Adjust the blower control unit after the test run.

Moisture is the biggest cause of filter bag clogging. The cause of moisture is usually condensation at low temperature. Especially when dealing with high temperature flue gas, the following methods can be used to prevent such accidents: avoid improper start-up; avoid dust collector Turn on when resistance is high; turn on at dew point. The dust collector is operated below the dew point, which is prone to problems. If the intake air is unevenly distributed, it is likely to cause local corrosion of the dust collector housing. Therefore, the dust collector should be prevented from working below the dew point. If it is unavoidable to start at low temperature, use insulation devices such as steam insulation or electric heating.

Air infiltration. Air infiltration often occurs in the dust collector's flange, access door or dust collector's mobile device. If the seal is not tight, the outside air enters the dust collector. When high temperature flue gas is treated, a low temperature zone is generated inside the dust collector, resulting in low temperature. Condensation, corrosion of the dust collector, resulting in a paste bag or knot of the filter bag.