Pulse Jet Baghouses
These are also called “high air to cloth ratio filters”.
Dust-laden gas from the process enters the dirty gas housing through the inlet duct and travels into the settling chamber portion of the baghouse. Here, the larger particles that fall out of the low-velocity gas stream are immediately directed into the hopper for removal. The gas with the remaining dust is distributed evenly toward the filtering elements or tubular-like filter bags. Filtered gas passing through the filter media is then exhausted from the clean-air plenum through the outlet duct.
In such a design, the filter bags are open at the top and closed at the bottom and the fabric is prevented from collapsing by individual supportive cylindrical cages.
The cleaning cycle consists of a momentary blast of compressed air directed through “blow” pipes positioned over each row of bags. When bags within a pulse cleaning collector are not cleaning properly, this is usually an indication of a system issue rather than bag problems.
Bags that are not cleaning properly will result in a build-up and the pressure drop across the baghouse will increase. On the other hand, bags that are cleaned too often or on a pulse duration setting that is too long will result in the filter media not building a sufficient cake, which will result in the occasional bleed. Over-cleaning can shorten the bag lifespan, while over-pulsing will lead to blinding of the filter media.