1、 Filtering mechanism

The filtration mechanism of dust removal filter bags mainly includes the following aspects:

Screening effect: When the diameter of dust particles is larger than the pores between the filter fibers, the dust is trapped on the surface of the filter material, achieving preliminary filtration. However, for fabric filter media, this effect is not significant in the initial stage, but after a certain thickness of dust layer is formed on the surface of the filter media, the screening effect will be significantly enhanced.

Inertial collision effect: When the dusty airflow passes through the filter fiber, large particles of dust deviate from the airflow streamline due to inertia, collide with the fiber, and are captured.

Hooking effect (interception effect): When fine dust moves within the streamline, if the radius of the dust particle is greater than the distance from its center to the edge of the fiber, it will be captured by the fiber.

Diffusion effect: For extremely small dust particles (such as those below 0.5 microns), irregular motion (Brownian motion) occurs under the collision of gas molecules, increasing the chance of contact with fibers and thus improving capture efficiency.

Gravity settling effect: Dust with large particles and high relative density naturally settles under the action of gravity.

Electrostatic effect: If the charge of dust is opposite to that of the filter material, the dust is easily adsorbed on the filter material, improving the dust removal efficiency; On the contrary, if the charges are the same, the dust is repelled but easily peeled off from the surface of the filter bag.

2、 Factors affecting filtration efficiency

Filter material: The material of the filter directly affects its filtration efficiency and durability. Common filter materials include polyester, PPS fiber, PP polypropylene, aramid fiber, etc., which have different temperature resistance, acid and alkali resistance, and wear resistance.

Filter material structure: The weaving method, porosity, fiber diameter, etc. of the filter material will affect its filtration effect. Generally speaking, the finer the fibers and the more moderate the porosity, the higher the filtration efficiency.

Dust characteristics: The particle size, density, shape, and chemical properties of dust can affect its deposition and capture effect on filter media.

Operating conditions: Operating temperature, humidity, airflow velocity, and cleaning method can all affect the filtration effect and service life of the dust removal filter bag.

3、 Filter effect evaluation

The filtration effect of dust removal filter bags is usually evaluated by the following indicators:

Filtration efficiency: refers to the filtering ability of dust removal filter bags for specific particle sizes and shapes. Generally speaking, the filtration efficiency of dust removal filter bags can reach over 98%, even up to 99.999%.

Breathability: Filter bags with good breathability can reduce airflow resistance and energy consumption while ensuring filtration efficiency.

Durability: including the tensile strength, wear resistance, and high temperature resistance of the filter bag, these properties determine the service life and stability of the filter bag.

4、 Practical application and maintenance

In practical applications, dust removal filter bags need to be cleaned and replaced regularly to maintain their good filtering effect and service life. At the same time, it is also necessary to pay attention to the installation and cleaning methods of the filter bag to avoid excessive cleaning, which may cause damage to the filter bag or a decrease in filtration efficiency.

The filtration effect of dust removal filter bags is influenced by various factors. By optimizing the material, structure, and operating conditions of the filter media, the filtration efficiency and durability of dust removal filter bags can be significantly improved.