As the core component of the industrial dust removal system, the damage or blockage of the filter bag directly affects the dust removal efficiency and equipment safety. Once the filter bag is damaged, dust will pass directly, resulting in substandard emissions, and even equipment failures and safety accidents; and the blockage of the filter bag will cause the system pressure difference to increase, affecting the stability of the airflow and increasing the equipment load. Therefore, understanding the common causes of filter bag damage and blockage will help take targeted measures to extend the life of the filter bag and improve the overall performance of the dust removal system.
1. Common causes of filter bag damage
Mechanical wear and impact
When industrial flue gas contains large particles or hard foreign matter, it will cause continuous scouring and wear on the filter bag, especially the bag mouth, folding parts and the bottom of the filter bag are most susceptible to wear and tear. Burrs or deformation on the surface of the bag cage will also scratch the filter bag fibers during operation, causing fiber breakage.
Improper installation
If the bag mouth is not sealed tightly or the installation position is deviated during the installation of the filter bag, the filter bag is prone to uneven force, resulting in local stretching and friction, causing deformation and tearing of the filter bag. In addition, if the size of the filter bag does not match the bag cage or the hole of the flower plate, friction or wear will be caused.
Temperature Exceeding Standard
The filter bags have a temperature limit. If the flue gas temperature exceeds the temperature range of the filter bag for a long time, the fiber will be thermally aged, carbonized or even melted, resulting in brittle cracking and damage to the material. Severe temperature fluctuations can also cause repeated stress damage to the filter bag due to thermal expansion and contraction.
Chemical Corrosion
The flue gas contains acids, alkalis and other corrosive gases, which will destroy the fiber structure of the filter bag and reduce its strength. Long-term operation will cause corrosion and cracking on the surface of the filter bag. This is particularly obvious when corrosion-resistant materials are not selected or protective measures are not in place.
Static Electricity Accumulation and Spark Triggering
Some dust working conditions have the risk of static electricity accumulation. If the filter bag is not designed with anti-static, static electricity sparks may be caused, resulting in local burning and damage of the filter bag. In addition, metal sparks or arcs can also directly burn through the filter bag.
Improper Cleaning
Excessive pulse injection pressure or too frequent cleaning will cause fatigue fracture of the filter bag; excessive vibration cleaning force or unreasonable frequency can also easily cause fiber fracture and damage of the filter bag.
2. Common causes of filter bag blockage
Dust is sticky
Dust containing grease, moisture or sticky substances is easy to form lumps on the surface of the filter bag, blocking the pores of the filter bag, resulting in increased airflow resistance. Common in rubber, plastic, food processing and other industries.
Irrational distribution of dust particle size
Ultrafine dust is easy to fill the gap between the filter bag fibers, and if the oversized particles are not settled or pre-treated in time, they will also accumulate and cause local blockage, affecting the filtration performance.
Excessive humidity and condensation
When the flue gas humidity is high or the temperature is lower than the dew point, condensation will occur on the surface of the filter bag, and the mixture of water and dust will easily form mud-like blockages, resulting in filter bag blockage and difficulty in cleaning.
Failure of the cleaning system
Failures of the cleaning system such as pulse valve leakage, insufficient injection pressure, and too short injection time will result in incomplete cleaning of the filter bag, and dust accumulation will increase blockage.
Mismatched filter bag material
Failure to select the appropriate filter bag material according to the dust characteristics. For example, using ordinary polyester filter bags to filter oily dust is easy to block and difficult to clean.
Abnormal operating parameters
If the wind speed of the dust collector is too high, it will cause strong dust impact and cause the filter bag to clog quickly; on the contrary, if the wind speed is too low, the dust deposition is difficult to discharge, which also causes clogging.
Summary
The damage and clogging of the filter bag are mostly caused by multiple factors such as mechanical wear, improper installation, over-temperature corrosion, static sparks, unreasonable cleaning, and dust properties and humidity. Enterprises should start from the material selection, design, installation, operation management and maintenance, and take scientific and reasonable protective measures, such as selecting wear-resistant and corrosion-resistant materials, ensuring installation specifications, controlling temperature, reasonably adjusting cleaning parameters, strengthening anti-static measures and pre-treating dust, etc., to reduce the occurrence of filter bag failures and improve the stability and environmental protection effect of the dust removal system.