Small bag filter

A small bag filter is a dry dust filtering device. After using the filter material for a period of time, due to screening, collision, retention, diffusion, static electricity and other effects, a layer of dust accumulates on the surface of the filter bag, which is called the initial layer. During the subsequent movement process, the initial layer becomes the main filtering layer of the filter material. With the help of the initial layer, filter materials with larger mesh holes can also achieve higher filtration efficiency. As dust accumulates on the surface of the filter material, the efficiency and resistance of the dust collector increase accordingly. When the pressure difference between the two sides of the filter material is large, some small dust particles that have already adhered to the filter material will be squeezed out, causing a decrease in the efficiency of the dust collector. In addition, excessive resistance of the dust collector can significantly reduce the airflow of the dust removal system. Therefore, after the resistance of the dust collector reaches a certain value, it is necessary to clean the dust in a timely manner. When cleaning, the initial layer should not be damaged to avoid a decrease in efficiency.

working principle

The dust removal efficiency of a small bag filter is inseparable from its dust removal mechanism. When the dusty gas enters the ash hopper through the lower intake pipe of the dust collector and the guide plate, due to the collision of the guide plate and the decrease in gas velocity, coarse dust particles will fall into the ash hopper, while the remaining fine dust particles will enter the filter bag chamber with the gas. Due to the inertia, diffusion, barrier, hooking, static electricity and other effects of the filter fiber and fabric, the dust is trapped in the filter bag, and the purified gas escapes from the bag and is discharged through the exhaust pipe. The accumulated dust on the filter bag is removed by gas backwashing method, and the removed dust is discharged to the ash hopper and discharged to the ash conveying device through the double-layer ash discharge valve. The dust accumulation on the filter bag can also be removed by spraying pulse airflow to achieve the purpose of cleaning, and the removed dust is discharged by the ash discharge device. The high dust removal efficiency of a bag filter is also inseparable from the filter material. The performance and quality of the filter material directly affect the performance and service life of the bag filter. The filtering material is the main material for making filter bags, and its performance and quality promote the progress of bag dust removal technology, affecting its application scope and service life.

The filter type dust removal device includes a bag filter and a particle layer dust collector. The former usually uses filter bags made of organic fibers or inorganic fiber fabrics as the filter layer, while the latter's filter layer is mostly composed of particles of different sizes, such as quartz sand, river sand, ceramic particles, slag, etc. As the powder repeatedly adheres to the outer surface of the filter bag, the powder layer continues to thicken, and the resistance value of the bag filter also increases accordingly; The pulse valve diaphragm sends a command, and when the left and right sides are submerged, the pulse valve opens, and the compressed air in the high-pressure air bag is opened. If there is no dust or it is small enough, the mechanical dust cleaning work will stop working.