Filter media are commonly used in industry:
① woven material, made of natural or synthetic fibres, wires and other woven filter cloth and filter, filter media that is most commonly used in industrial production. Such materials are cheap, easy to clean and replace, 5~65 μ m is the minimum size that can be withheld. Made of polyamide, polyester or polypropylene fiber mesh, texture uniformity, corrosion and fatigue, are gradually replacing other fabric filter cloth.
② porous solids, including unglazed porcelain, metal or glass, or plastic powder bonded porous plastic tubes, and so on. Such materials can retain the minimum size for 1~3 μ m, often used to contain small amounts of tiny particles of suspensions.
③ stack media, such as sand and gravel, charcoal and diatomaceous earth, granular material, stacked layers of non-woven fibers such as cotton or glass. Solid content is typically used to process a small number of suspensions, such as urban water supply and purification of sugar solution. In addition, industrial filter paper can also be combined with the filter media to intercept a small amount of fine particles in suspension. Fabrication and application of porous polymer membranes have a great development, more small particles filter should be used to obtain highly clarified liquid. Apply filter to 0.1~1 Mu m grain film called microporous membrane suitable for filtering particles 0.01~0.1 μ m film called ultrafiltration membranes (membrane). Microporous membrane and ultrafiltration membranes are widely used in medicine, food and biochemical industries.