Bag Filter Applications

Recovery of particulate matter from exhaust gas is important for any industry to avoid pollution problems and recovery of finished product. If material recovery in powder form is desirable and particulate size is very fine, a bag filter is the best choice for recovering particulate matter. In many filtering applications, bag filter is used as liquid filtration such as bulk chemical, food industry (vinegar), waxes, coolants, paint, varnishes. For gaseous filtration in industry, bag filter is used for dust removal. General components of bag filter

• bag filter housing
• filter bags
• bag cages
• filter bag assembly
• pulse-jet air cleaning assembly
• air bleeding assembly

Bag Filter Work Priciple

bag filter housing

• the dust-laden air enters the bag filter housing trough the bustle.
• the air is uniformly distributed avoiding channeling.
• Initially a coat of material forms on the bags. Subsequently, the coat acts as the filtering medium.
• the dust is accumulated on filter elements while the air passes thorough the filter bags from outside to inside.
• the accumulated powder is dislodged from the bags by reverse pulse-jet air intermittently.
• the dislodged powder falls on bottom cone and is discharged through powder discharge valves.
• the dust free air is sucked by induced draft fan and is exhausted to atmosphere.

Bag filter can be made from nylon, polypropylene or polyester. Polypropylene bag filter is often used as filtering material. It is compatible in most situations for filtering acids, alkalis, aromatics, alcohols and ethers. Most bag filters are designed for applications with a desired filtration rate from 1 to 1000 micron.

You may want to check out the other article on Bulk Packaging.