Glossary
Baghouses
Fibreglass filter bag
Also known as fibreglass bag, glass-fibre filter bag, woven fibreglass bag.
A fibreglass filter bag is woven from glass-fibre yarn, normally finished with a PTFE, silicone or graphite coating to improve flex resistance and dust release. Continuous service rating is up to 260 °C, peaking briefly higher. Fibreglass is the standard bag medium for coal-fired utility reverse-air baghouses and for high-temperature cement-kiln duty.
Strengths
- Highest continuous-temperature rating of mainstream media (260 °C)
- Dimensionally stable, low thermal shrinkage
- Compatible with sulphurous flue gas after appropriate coating
Weaknesses
- Brittle — does not tolerate sharp flexing from aggressive pulse-jet cleaning; favours reverse-air design
- Limited cleanability — cake can adhere; often paired with a PTFE membrane overlay for tighter outlet limits
- Hydrolyses below the acid dew point in sulphurous gas
Acoustic cleaning compatibility
Sonic horns installed on a reverse-air fibreglass baghouse supplement the gentle reverse-air cycle without the bag-flex fatigue that would arise from more aggressive primary cleaning. This is a particularly well-suited combination on coal-fired utility duty.
Related terms
Related terms
- Filter bagA filter bag is the cylindrical fabric sock that traps particulate inside a fabric filter. Media selection depends on temperature, gas chemistry, dust load and cleaning cycle.
- Reverse-air baghouseA reverse-air baghouse cleans bags by isolating a compartment and passing low-pressure clean air through the bags in the reverse direction. Common on coal-fired utility duty.
- PTFE-membrane filter bagA PTFE-membrane filter bag has a microporous Teflon membrane laminated to the surface of a base felt. Particulate is trapped on the membrane, not within the depth, giving sub-mg outlet performance.