Filter cloth selection an important role of filtration
Filter press is increasingly applied by more and more industries such as metallurgy, mining, printing as an effective and affordable equipment of solid-liquid separation. As an essential factor of filter press, filter cloth plays an important role to ensure clear filtration, dry filter cake and short filter cycle.
- Filter cloth selection mainly depends on
- Yarn Types
- Weave Patterns
Polyester (PE) filter cloth
The prominent property for polyester fabric is its strongest acid resistance among existing synthetic fabrics. It is widely recognized as an outstanding and popular filter cloth for its high operating temperature up to 302℉, high tensile strength and good elongation.
Polypropylene fabric is characterized by sleekness, excellent permeability and nil moisture absorption. Its excellent cake release will significantly shorten cleaning time as well as filter cycle. It also has excellent resistances against most acids and alkalis. Its constant working temperature is rated at 280℉.
Nylon filter cloth
Nylon filter cloth features optimum abrasive resistance and strong alkali resistance. It is often found in miner and coal industries for its best abrasion proof. The only shortage is that its chemical instability under high temperature when it will release toxic substance and pollute the solutions. So, nylon filter cloth is not accepted by food & beverage and pharmaceutical.
Vinylon filter cloth
Thanks to its strongest alkali resistance, vinylon filter cloth is suitable for caustic condition. Its working temperature is less than 140℉.
Properties of Frequently Used Filter Fabrics
|Elongation||30%-40%||Better than PE||12%-25%|
|Recovery||Excellent||Slightly better than PE||Poor|
|Heat Resistance||170 °C||90 °C||100 °C|
|Softening point||230 -240 °C||140 -150 °C||200 °C|
|Melting point||255 -265 °C||165 -170 °C||220 °C|
Multifilament yarn is twisted together by monofilament yarns. The cloth fabricated by multifilament yarns has a smooth surface, high tensile strength, average particle collection efficiency and cake release.
Monofilament yarn is single and continuously extruded from synthetic resin. It has excellent cake release, resistance to blinding and low particle collection efficiency.
Staple (spun) yarn
Staple yarns are fabricated of chopped filaments. These short fibers have low tensile strength, a large surface area. Staple fabric has poor cake release but excellent particle retention.