Most of the daily damage to baghouse dust collectors results from the long-term superimposed effect of multiple factors including filter bags, dust cleaning
systems, structural components and others. The core damage causes can be classified into the following major categories:
Core Damage Causes of Filter Bags
Mechanical Wear: Direct scouring of the front-row filter bags by high-speed dust-laden airflow on the air inlet side, rust-induced burrs, deformation and bending of
the filter cage, and excessive injection pressure causing offset blowing on the bag body will all lead to fiber drawing, local perforation and strip-shaped damage of the
filter bags.
Dew Formation, Bag Clogging and Blockage: When the flue gas temperature is lower than the dew point, air leakage occurs in the equipment, or water leaks from the
pipeline, wet dust will adhere to the surface of the filter bag, blocking the pores of the filter bag, causing the operating resistance to rise sharply. Long-term uneven
stress accelerates the aging and damage of the filter bag.
High-temperature Burnout: High-temperature particles and sparks enter the box along with the flue gas, and the accumulated dust in the dead corners of the ash
hopper spontaneously combusts, directly burning the filter bags into small holes or strip-shaped cracks. In severe cases, the entire set of filter bags in the box will be
scrapped.
Chemical Corrosion: The flue gas contains corrosive components such as acids and alkalis, which cause hydrolysis and oxidation reactions in the fibers of the filter bag.
The filter bag becomes brittle as a whole, its strength drops significantly, and ulcerative damage occurs.
Indirect Damage Caused by the Dust Cleaning System
Abnormal Injection Parameters: If the injection pressure exceeds 0.2MPa for a long time and the injection cycle is too short, the filter bag will repeatedly expand and
contract at a high frequency, leading to rapid fatigue fracture of the fibers and a greatly shortened service life.
Dust Cleaning Component Failure: Fatigue damage of the pulse valve diaphragm, offset and misalignment of the nozzle cause local airflow to concentrate and impact
the bag opening, resulting in local wear of the bag opening and loosening and detachment of the filter bag.
Unqualified Air Source Quality: The content of oil and water in the compressed air exceeds the standard. The oil forms an oil film on the surface of the filter bag,
increasing the dust adhesion by 3-5 times. After the dust cleaning fails, the filter bag operates under high load for a long time, which accelerates the damage.
Defects in Equipment Structure and Operating Parameters
Uneven Airflow Distribution: Without an air inlet flow guide device, the filtration wind speed in local areas far exceeds 1.5 times the design value, the wear rate of filter
bags increases exponentially, and the front-row filter bags are concentratedly damaged.
Unreasonable Installation Layout of Filter Bags: The spacing between filter bags is too small. Long-term collision and friction between bags, and between bags and the
inner wall of the box, lead to excessive local filtration load, insufficient dust cleaning, and repeated dust accumulation and wear.
Excessive Filtration Wind Speed: The actual operating wind speed far exceeds the design value, which continuously intensifies the friction and scouring effect of dust
particles on the filter bag. The wear speed of the filter bag is 2-3 times faster than that under normal working conditions.
Inducing Factors of Improper Daily Operation and Maintenance
Failure to Conduct Periodic Inspections: Long-term non-inspection of filter cages, injection components and box seals leads to small hidden dangers that are not dealt
with in time, which gradually evolve into large-area damage of filter bags.
Unreasonable Dust Cleaning Strategy: If the dust cleaning cycle is set too long, the dust layer on the surface of the filter bag will be too thick, the resistance will remain
high for a long time, and the filter bag will be in a state of high tension for a long time to accelerate fracture.
Inadequate Thermal Insulation and Sealing: The air leakage points of the box are not blocked in time. In a low-temperature environment, dew forms repeatedly inside
the box. The filter bag is in a high-humidity environment for a long time, and the fiber strength continues to attenuate.
