PPS (Ryton) filter bags, up to 190 °C.
PPS (polyphenylene sulphide, often called Ryton) is the filter bag media for acidic or alkaline flue gas up to 190 °C continuous. It resists hydrolysis and chemical attack, which makes it the standard choice for coal-fired boilers and waste incineration. Its weakness is oxidation: high oxygen levels at high temperature make it brittle.
- Continuous temperature
- up to 190 °C
- Chemical resistance
- Acids, alkalis, hydrolysis
- Main limit
- Oxidation at high O₂
- Surface option
- Ultra-microfibre layer
Where it works
- Coal-fired boiler flue gas
- Waste incineration and biomass
- Gas with SOx and moisture
- Temperatures from 150 to 190 °C
Where to avoid it
- High oxygen content combined with high temperature
- Continuous operation above 190 °C
- Strong oxidisers such as NO₂ at high levels
Typical applications
Coal-fired boilers, biomass combustion, waste incineration, ash handling.
How it compares
| Fibre | Continuous temperature | Strengths | Watch out for | Typical duty |
|---|---|---|---|---|
| Polyester | up to 150 °C | Low cost, good abrasion resistance | Hydrolysis in hot, moist gas | Cement mills, packing, crushers, general dedusting |
| PPS (Ryton) | up to 190 °C | Resists acids and alkalis | Oxidation at high O₂ | Coal-fired boilers, waste incineration |
| Meta-aramid (Nomex class) | up to 204 °C | Strong, abrasion resistant | Acid attack and hydrolysis | Asphalt, foundry, cement raw mills |
| P-84 polyimide | up to 240 °C | Trilobal fibre, fine-dust capture | Hydrolysis in very moist gas; cost | Cement kilns, waste-to-energy |
| Fibreglass | up to 260 °C | Highest temperature, chemically stable | Flex and abrasion; needs a finish | Reverse-air kilns, calciners, furnaces |
| Ultra-microfibre surface (13–15 µm) | set by base fibre | ≤5 mg/Nm³ with low pressure drop | Must be specified to the dust | Any of the above where emissions matter |
What to send for a recommendation
- Collector type (pulse-jet, reverse-air or shaker) and the collector drawing
- Bag diameter, length, top and bottom construction, and quantity
- Continuous and peak gas temperature
- Dust chemistry, moisture, acid dew point and particle size
- Current bag specification, bag life and differential pressure
- Emissions target
Questions, answered.
What is PPS filter bag media?
PPS is polyphenylene sulphide, a fibre that resists acids, alkalis and hydrolysis up to 190 °C. It is the most common media for coal-fired boiler baghouses.
Why do PPS filter bags fail?
The most common cause is oxidation: high oxygen at high temperature makes the fibre brittle. Temperature excursions above the rating and abrasion are the next most common causes.
PPS or P-84 for a boiler?
PPS is usually more economical for boilers below 190 °C. P-84 is chosen when temperature runs higher or finer dust capture is needed.
Send us your dust profile.
Temperature, chemistry, moisture, particle size and your emissions target. An application engineer replies within one working day, usually with a media specification within two.