Baghouses
P84, Nomex and Ryton filter media
Also known as P84 filter bag, Nomex filter bag, Ryton filter bag, PPS filter bag, polyimide filter bag, aramid filter bag.
P84, Nomex and Ryton are three mainstream high-temperature synthetic filter-bag media used in industrial baghouses. Each is engineered for a different combination of temperature and gas chemistry.
Side-by-side
| Media | Polymer | Continuous max temp | Strengths | Typical use |
|---|---|---|---|---|
| Nomex | Meta-aramid | 200 °C | Good flex life, dimensional stability | Asphalt, foundry, metallurgical off-gas |
| P84 | Polyimide | 240 °C | High fibre surface area; excellent dust release; ideal for sticky dust | Cement kiln, lime kiln, biomass, iron-ore pelletising |
| Ryton (PPS) | Polyphenylene sulphide | 190 °C | Excellent acid resistance, including sulphurous and dilute mineral acids | Coal-fired utility baghouses, sulphur recovery, WtE |
Selection logic
The choice is usually constrained by two questions: what is the highest continuous temperature? and is the flue gas chemically aggressive — sulphurous, acidic, hygroscopic? P84 is favoured where dust is sticky and temperature is high. Ryton is favoured where SO₂/SO₃ chemistry attacks lesser media. Nomex is the budget high-temperature option for less aggressive duty. For sub-1 mg/Nm³ outlets, any of these are typically overlaid with a PTFE membrane.
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.
- 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.
- Fibreglass filter bagA fibreglass filter bag is woven from glass-fibre yarn and rated for continuous service to 260 °C. The standard bag for coal-fired utility reverse-air baghouses and high-temperature cement duty.