The bag filter mainly uses filter material (fabric or felt) to filter the dust-containing gas to achieve the purpose of dust removal. The filtration process is divided into two stages. First, the dust-containing gas passes through the clean filter material. At this time, the filtering effect is mainly the retention of the filter material fibers. Secondly, when the retained dust continues to increase, part of the dust is embedded in the filter material, and part of the dust is covered on the surface of the filter material to form a dust layer. At this time, the dust layer is mainly used to filter the dust-containing gas. After the dust-containing gas enters the dust collector, the airflow speed decreases, and the larger particles in the smoke are directly deposited into the ash hopper. The remaining dust particles are filtered through the filter bag from the outside to the inside. The clean smoke is discharged from the inside of the filter bag, and the fly ash is blocked. Stay on the outside of the filter bag. With the accumulation of ash, the pressure difference between the inside and outside of the dust removal filter bag gradually increases. When the pressure difference reaches the set value, the pulse valve diaphragm automatically opens, and pulse air is sprayed into the filter bag through the nozzle, and the filter bag expands. The dust attached to the filter bag falls off to achieve the effect of dust removal.

The structure of the bag filter

The internal structure of the bag filter is mainly composed of the upper box body, the middle box body, the lower box body (ash bucket), the ash cleaning system and the ash discharge mechanism. The bag filter is mainly composed of four major systems, namely, the ash cleaning system, the control system, the inspection system, and the safety protection system (including the boiler ignition and fuel injection, the pre-coating system during low-load operation and stable combustion, and the protection filter Bag; When the flue gas temperature exceeds the set value, the emergency water spray system is activated to reduce the flue gas temperature and protect the filter bag. The dust removal system is the digestive organ of the bag filter, and the operation effect of the bag filter depends to a large extent. In the cleaning mechanism and its control system.

Types of bag filter

The bag filter equipment mainly includes pulse jet bag filter, air box pulse bag filter, mechanical blow bag filter, mechanical vibration bag filter and other equipment in terms of cleaning methods.