In today’s post we’ll be going back to the basics of the dust collector industry and filter bags. We’ll be diving into filter construction to help us build a foundation of better understanding, or for those who have been in this industry for a while, a refresher course on the basics!
Filter bags used in the industrial dust collection industry can be made of woven or nonwoven materials. Nonwoven materials can further be divided as felted or membrane. Most bags are either completely or partially made by weaving since nonwoven fabrics are generally attached to a woven base called a scrim. Woven filters are made of yarn with a definite repeated pattern. Felted filters are composed of randomly placed fibers compressed into a mat and attached to loosely woven backing material.
A membrane filter is a special treatment where a thin, porous membrane is bonded to the scrim or support fabric.
- Woven Filters: Generally used with low energy cleaning systems such as shaker or reverse air baghouses.
- Felted Filters: Usually used with higher energy cleaning systems such as pulse jet dust collectors.
- Membrane Filters: Developed in an effort to achieve high efficiency particle capture and to handle flue gas conditions where high moisture resulting high pressure drop problems frequently occur.