In a Baghouse, dirty air flows into and through a number of cloth filter bags that are placed in parallel. The filters remove the particulate from the gas stream while the cleaned gas passes through the cloth and is exhausted to the atmosphere. The fabric filters do some filtering of the dust particles; however, their more important role is to act as a support for the layer of dust (filter cake) that quickly accumulates on it.
This layer then acts in a highly efficient manner to filter both the large and small particles from the gas stream and becomes the main filtration mechanism throughout the process.
Baghouses have a very high collection efficiency for both large and small particles, they are modular in design, and they can operate on a wide variety of dust types and wide range of flow rates with reasonably low pressure drops.