Introduction To Polypropylene Filter Bags

A filter bag is a filter element that allows the liquid in the suspension or the gas in the gas flow, containing solid particles, to pass through under the action of an external force, and intercepts the solid particles, so as to achieve the separation of solid particles from the liquid or gas. It is mainly used for the purification and clarification of fluids (liquid or gas).

Polypropylene filter bags are bag-shaped filtration components made of polypropylene (PP). They feature a three-layer design, with a pre-filter layer, primary filter layer, and outer layer, formed through needle-punched non-woven fabric to create a three-dimensional, deep-loop structure. Performance is enhanced through surface treatments, including burnishing, polishing, or film coating. 

The filtration precision ranges from 1 to 200 microns, with sealing materials including stainless steel rings, galvanized steel rings, and polypropylene plastic rings. Sewing techniques employ either thread stitching or heat fusion welding. These PP filter bags are resistant to strong acids, strong alkalis, and various chemical substances, operating at temperatures up to 90-110°C. Polypropylene filter bagsare widely used in petrochemicals, coatings, biomedicine, automotive manufacturing, food and beverage, industrial dust removal, and water treatment sectors.

PP Filter Bag Material Properties:

Polypropylene fiber, melt-blown or needled process, is used

Strongly acid or alkali (pH 1-14).

Working temperature: ≤90℃ (100℃ for short time).

Polypropylene bag filter Filter Accuracy:

Range: 1μm ~ 200μm

Common specifications: 5μm, 10μm, 25μm.

PP Bag Filter Preponderance:

High cost performance; single use reduces cross-contamination.

Good hydrophilicity, suitable for aqueous solution.

No release, compliant with food-grade certification (e.g. FDA).

Bag Filter Typical Application:

Chemical pre-filtration (coatings, resins).

Food and beverage clarification (juice, beer).

Water treatment: pretreatment (river water, circulating water).