Why do filter cartridges catch fire?

The causes of filter cartridge fires are usually related to the following factors:

Dust Characteristics:

If the dust being processed (such as rust dust) is a flammable solid with a small particle size (e.g., an average particle size of 100-150 μm), 

its ignition point is low (240-439℃), making it easily ignited. The smaller the dust particle size, the larger the specific surface area, and the easier it is to burn.

External Ignition Source Introduction:

External hot particles (such as sparks from electric welding, gas cutting, or high-speed steel shot impacts in a shot blasting machine) drawn into the filter cartridge may directly ignite the dust or the filter media.

Temperature Increase and Spontaneous Combustion:

During equipment operation, mechanical energy is converted into heat energy, causing the system temperature to rise. 

In a high-temperature, oxygen-rich environment, the oxidation reaction of dust accelerates. 

If the accumulated heat exceeds the heat dissipation capacity, it may cause spontaneous combustion of the dust.

Static Electricity Accumulation: 

Dust particles generate static electricity through friction in high-speed airflow. 

When the static potential accumulates to a certain level, it may produce a static spark. 

If the discharge energy reaches the minimum ignition energy of the dust, it can cause a fire.

Filter Media Material: 

If the filter media is made of flammable materials such as paper or polyester fiber, it is easily ignited, increasing the risk of fire.

Improper Design or Maintenance: 

An unreasonable dust collector design (such as uneven airflow distribution or untimely dust removal), 

or long-term neglect of dust accumulation, can also lead to dust buildup and potentially cause a fire.

To prevent filter cartridge fires, it is recommended to use flame-retardant filter cartridges, 

strengthen grounding for anti-static purposes, regularly clean accumulated dust, control ignition sources, and provide safety training to operators.