A bag filter or fabric filter is an air pollution control equipment that effectively removes particulates out of air / gas, released from industrial or commercial processes. It is used in power plants, pharmaceutical processing, steel mills, food manufacturing, chemical, and other industrial establishments.
Main Components of Bag Filter:
Dust-laden air enters the lower portion, i.e. the bag filter hopper. The air moves through the filter bag, which holds the dust particles on the surface of the bag. Clean air passes through bags and plenum to the Bag filter outlet. On the outside of the bag filter, the dust is accumulated. There is an increase in differential pressure across filter bags with the collection of dust on the bags. Timekeeper actuated closed pulse valves, pulse the compressed air to open the valves.
There is a flow of high pressure air (4 to 5 bar), from the compressed air header to blow tube. It is throw out from the blow tube by nozzles at a high rate (primary air flow). Air from all nozzles generate secondary airflow. The united effect of primary and secondary air origins an instant pressure rise on clean side of the filter bags. This causes a reverse flow of air through the bags, therefore removing the dust particles clasped on the bags outer surface. By this process, the dust gathered is discharged from the bags and moves into the hopper. It is released by a suitable device from the hopper, i.e. Rotary valve. And the differential pressure is maintained across the Filter Bag.
Features of Dust Collection System