Aramid Filter Bags
Needle-punched felt aramid filter bags are a high-temperature, heat-resistant filter material made primarily from aramid fibers (Nomex and Kevlar) through a needle-punching process. It operates stably and long-term under working conditions of 180–240°C and is particularly suitable for dust removal systems that require high temperature, high efficiency and long life.
These filter bags typically consist of three layers:
- Surface layer: Dense synthetic fiber layer (improves filtration accuracy)
- Middle layer: Main needle-punched felt layer (captures dust and provides strength)
- Bottom layer: Base fabric layer (enhances overall mechanical properties).
Main Performance Features
☑ Excellent high-temperature resistance: Continuous operating temperatures reach 200°C and transient temperature resistance reaches 240°C, making it suitable for high-temperature flue gas filtration.
☑ Flame retardant and self-extinguishing: Aramid is an inherently flame-retardant fiber that does not melt or drip and self-extinguishes in the event of fire.
☑ Strong oxidation resistance: Able to operate stably and long-term in environments with high oxygen content and high temperatures.
☑ High mechanical strength: High breaking strength and excellent abrasion resistance, capable of withstanding pulse backflushing and mechanical vibration cleaning.
☑ Excellent dimensional stability: Low thermal shrinkage and deformation resistance ensure filtration stability.
☑ Excellent chemical stability: Resistant to corrosion from weak acids, weak bases, and hydrocarbon gases.
☑ Long service life: Compared to other similar temperature-resistant filter media, this filter has a longer service life than ordinary polyester filter bags.
Types of Aramid Needle Felt
| Type | Main Component | Features | Working Temperature |
|---|---|---|---|
| Meta-Aramid Needle Felt | Nomex | Excellent heat resistance, inherent flame retardancy, oxidation resistance, good insulation | Continuous ≤ 200°C, Peak ≤ 240°C |
| Para-Aramid Needle Felt | Kevlar | High tensile strength, great wear and tear resistance, anti-tear, slightly lower heat resistance | Continuous ≤ 180°C, Peak ≤ 200°C |
| Blended Aramid Needle Felt (Meta + Para) | Meta-Aramid + Para-Aramid | Balanced strength and heat resistance, cost-effective | Continuous ≤ 200°C |
Processing and surface treatment technology of aramid needle felt
✱ Singeing: Removes surface hair, smoothing the filter media and preventing dust clogging.
✱ Calendering: Increases filter media density and smoothness, improving dust removal performance.
✱ Water & Oil Repellent: Increases moisture resistance and prevents condensation and agglomeration.
✱ PTFE Impregnation: Enhances chemical resistance and anti-adhesion properties.
✱ PTFE Membrane: Surface treatment with a microporous membrane improves filtration accuracy and backwash cleaning performance.
Typical Applications of Aramid Needle Felt Filter Bags
Their reliable long-term performance makes them the ideal choice for harsh and complex working conditions.
- During asphalt production, the exhaust gas contains a large amount of hot, oily dust. Aramid filter bags offer superior anti-adhesion and high-temperature resistance, effectively preventing dust caking and bag blinding. They ensure stable operation of the dust collector and significantly extend the service life of the filter bags.
- In cement plants, dust from kiln ends, coolers, and mills is characterized by high concentration and fluctuating temperature. Aramid needle felt filter bags exhibit excellent thermal and dimensional stability, allowing them to withstand frequent pulse cleaning and hot gas impact while maintaining high filtration efficiency and durability.
- Exhaust gas in chemical processing often contains corrosive gases and fine particulate matter. Aramid filter bags treated with PTFE impregnation or water- and oil-repellent finishes can effectively resist acid and alkali corrosion and moisture damage, maintaining high filtration efficiency even under chemically aggressive and high-temperature conditions.
- Metallurgy and power industries generate high-temperature, high-concentration, oxygen-rich flue gases. Aramid filter bags, with their exceptional oxidation resistance and mechanical strength, perform reliably under such demanding conditions. They are suitable for dust collection in electric furnaces, boilers, sintering machines, and metallurgical exhaust systems.
- Waste incinerators and coal-fired boilers produce hot and corrosive flue gases. Aramid needle felt, when blended with PPS or PTFE fibers, offers enhanced acid/alkali and thermal resistance, ensuring efficient dust collection performance even in high-temperature, humid, and corrosive environments.
Filmedia® Offers Custom Aramid Filter Bag Services
Filmedia® is dedicated to providing customers with high-performance, fully customized aramid filter bag solutions to meet the unique operating requirements of various industrial dust collection systems. Whether selecting filter media, sizing specifications, or designing accessories, we provide professional support and guidance to ensure optimal filter bag performance in your application.
☑ Customized Filter Media
Filmedia® offers various types of aramid needle-punched felt filter media based on your operating environment, dust characteristics, and temperature requirements.
☑ Customized Sizes
Filmedia® can customize filter bags to your equipment specifications in terms of length, diameter, opening, bottom shape, etc. We offer both standard and non-standard sizes.
☑ Customized Accessories
We offer a variety of custom accessories for different dust removal systems:
- Connectors such as metal rings, plastic buckles, and clamps
- Filter bag support frames
- Accessories made of special high-temperature or corrosion-resistant materials
☑ Installation and Usage Guide
Filmedia® provides professional filter bag installation and usage guidance:
- Installation Steps and Precautions
- Daily Maintenance and Cleaning Optimization Solutions
- Service Life and Performance Monitoring Recommendations