Dust Collector Filter Bag Media: A Buyer's Guide to Fibres and Finishes

In a cement plant, steel works or power station, the dust collector runs around the clock, and its filter bags decide how clean the stack is and how often the plant has to stop. Choose the wrong media and bags blind, burn or rot early. Choose the right one and they last for their full service life.

This guide is for filter bag makers and distributors buying dust bag filter media in rolls.

Start from the process conditions

The right media is decided by the gas, not the dust alone. Before choosing, collect these facts from the plant:

• Temperature – normal running temperature and peaks.
• Moisture – humidity and the risk of condensation.
• Chemistry – acids, alkalis or oxidising gases in the stream.
• Dust – particle size, abrasiveness and stickiness.
• Cleaning – pulse-jet, reverse-air or shaker, and how often.

Choosing the fibre

• Polyester (PET) – strong, durable and chemical resistant; the versatile choice for moderate temperatures.
• Polypropylene (PP) – lightweight, moisture and chemical resistant.
• P84 – high temperature, thermal and chemical resistance.
• PPS – resistant to heat, acids, alkalis and hydrolysis; common in coal-fired boilers.
• PTFE – extreme chemical resistance and low friction for the harshest conditions.
• Meta-aramid – flame resistant and thermally stable.
• Homopolymer acrylic – chemical and moisture resistant.
• Copolymer acrylic – flexible, durable and chemically resistant.

Finishes

Needle felts for filter bags are usually finished to improve dust release and protect the fibre. Common finishes include singeing and calendering for a cleaner surface, heat setting for dimensional stability, and water-, oil- or acid-resistant and PTFE treatments. Tell us the problem the bags face – sticky dust, moisture, chemical attack – and we will recommend the finish.

Industries served

Our media is used in cement and building materials, metal smelting, steel, lime, coal-fired power, waste incineration, chemicals, ceramics, glass, aerospace, aluminium reduction, rubber, blast furnaces, pharmaceuticals, textiles, food, beverage and edible oil.

The media is made by needle punching on our own lines. For HVAC filters, see our air filtration media; for heat and fire protection, our insulation felts.

Signs the media is wrong for the job

• Rising pressure drop that cleaning cannot bring down – the media is blinding; the surface finish or fibre may need to change.
• Brittle, discoloured or shrunken bags – heat or chemical attack; a more resistant fibre is needed.
• Holes at the cuff or along the cage wires – abrasion or flex damage; check weight, scrim and fit.
• Dust at the stack – leaks or too open a media; check the finish and the bag seams.

Share these observations when you send an enquiry. They tell us more than the old bag's specification alone.

How to write the specification

• Fibre – or blend, chosen for the conditions above.
• Weight and thickness – gsm and target thickness.
• Scrim – supporting scrim if needed for strength.
• Finish – surface and chemical finishes.
• Roll format – width and length to suit your bag cutting.
• Application – the industry and collector type, so the grade is set up for it.

Mistakes to avoid

• Choosing by temperature alone. Moisture and acid can destroy a fibre well below its temperature limit.
• Copying the old bag without asking why it failed. If bags failed early, the cause should change the specification.
• Skipping the finish. A good finish can be the difference between bags that release dust and bags that blind.

What to ask a supplier

• Do you make the needle felt in-house?
• Which fibres and finishes can you supply?
• Will you make media to my specification and conditions?
• Can you send sample media for a trial set of bags?
• Can I combine filter media with other products in one container?

How we supply dust bag filter media

Samridhi Crreation has manufactured nonwovens in India since 2004. Our filter media is synthetic only – no glass-fibre media – and made to order to the customer's specification; there are no stock grades. We supply filter bag makers and distributors worldwide. The minimum order is one 40'HQ container, and 5–6 different products can be combined in it. We ship FOB India from Mundra or Nhava Sheva, with CIF and DAP on request, and provide REACH and SVHC declarations for customers in the European Union. Samples are free, and we pay the courier.

See fibres and industries on our dust bag filter media page, or send us your process conditions for a recommendation and samples.