Causes of clogging of bag filter bags

28/07/2020

    The bag filter is a new type of filtering system. The filter bag is supported by a metal mesh inside. The gas flows in from the inlet and flows out from the outlet after being filtered by the filter bag. Impurities are intercepted in the filter bag and can be used continuously after replacing the filter bag. Bag filter is a kind of multi-purpose filtering air purification equipment with novel structure, small size, simple and flexible operation, energy saving, high efficiency, airtight work, and strong applicability.

    The reasons for the clogging of the filter bag of the bag filter are that the filter speed is too high, the dust is too fine, the dust is sticky, the filter bag is not cleaned, the filter bag is stuck, condensation, and compaction. If the filter wind speed of the dust collector exceeds the design standard of the filter bag, it is easy to cause the fine dust in the flue gas to enter the inside of the filter bag fiber, and the blockage resistance of the filter bag increases. It is better to use coated filter material, coated filter material, or pre-coating the surface of the filter bag. For dust with high viscosity, it is necessary to reduce the filtering wind speed or increase the pressure of pulse blowing or adopt the method of offline pulse cleaning filter bag, but the better way is to increase the filter area, reduce the filter wind speed, and extend the filter bag Service life.

    The reasons for the poor cleaning of bag filter bags include frequent cleaning times and long cleaning time. Frequent cleaning times and excessive cleaning pressure will loosen the fiber structure of the filter bag, which will increase the fine dust in the flue gas and 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 filter accuracy of the filter bag. If the dust removal time is too short, the dust on the surface of the filter bag is not completely cleaned, and then the filter will start. The dust will gradually accumulate on the surface of the filter bag, which will cause the filter bag to block. To solve this problem, you can pass several times After the trial run, adjust the injection controller.

    Moisture is a major cause of clogging of the bag filter. The cause of moisture content is usually condensation at low temperatures, especially when dealing with high-temperature flue gas. The following methods can be used to prevent this situation: avoid improper startup; Avoid starting the dust collector when the resistance is large; starting below zero. The dust collector runs below the zero points, which is prone to problems. If the air intake is unevenly distributed, it is easy to cause local corrosion of the dust collector housing. Therefore, the dust collector should be avoided from working below zero. If it is unavoidable to start at a low temperature, a heat preservation device should be used.

    Air infiltration often occurs at the flange of the dust collector, the inspection door, or the movable device of the dust collector. If the seal is not tight, the outside air enters the dust collector. When high-temperature flue gas is processed, a low-temperature area will be generated inside the dust collector, resulting in low-temperature Condensation at the place, corrodes the dust collector, and causes paste or compaction of filter bags.

    The above is RT air filtech manufacturer’s explanation of the reasons for the blockage of the bag filter bag and the corresponding treatment methods. Our company produces primary efficiency filters, medium efficiency filters, high-efficiency filters, high-temperature resistant filters, and comes with a Fan filter unit (ffu) and other purification equipment and clean room product manufacturers.