Filtration Media and Elements
Filtration media and elements are designed to remove suspended debris from a process stream. Filtration is a physical or mechanical process which removes insoluble particles from a liquid or gas. Base fluids may include coolants, corrosive chemicals, gasoline, diesel fuel, hydraulic fluid, lubricants, water, oil, inks, dies, and paints. Particulates and contaminants can also be filtered from gas or air. Filtration grade or Beta ratio is the most important specification to consider when selecting filtration media and elements. This micron-rating characterize a filter’s ability to remove contaminants based on particle size. Water absorption, pressure drop, maximum liquid flow, and maximum gas flow are also important parameters to consider. Choices for housing material include: aluminum, plastic, steel, stainless steel, and Teflonregistered: ® (DuPont Dow Elastomers). Some filtration media and elements are portable, reusable, or disposable. Others have an integral bypass, provide high Delta P indication, or meet requirements from the U.S. Food and Drug Administration (FDA).
There are four main configurations for filtration media and elements: bulk filter media, cartridge, housing only, and housing and filter assembly. Bulk filter media has a defined, porous structure and serves as a particle collector. Filtration media and elements in this category include only the filtration media itself; cartridges, holders, and other receptacles are sold separately. Types of bulk filter media include: activated carbon, activated clay, cellulose, ceramic, cotton, diatomaceous earth (DE), glass fiber, ion exchange resins, metals, minerals, paper, nylon, sand, synthetic fiber, Teflon, polyethersulfone (PES), polyester, polypropylene (PP), polytetrafluoroethelyne (PTFE), polyvinylidene fluoride (PVDF), polyvinylidene chloride (PVDC), and polysulfone. The base fluid and media type determines the bulk filtration media to select.
The filtration media and elements product category also includes cartridges, housing-only products, and housing and filter assemblies. Cartridges hold the bulk filter media and perform the actual process of filtration. Cartridges do not have moving parts, but perform filtration passively as fluids pass through. There are two basic types of cartridges: pre-filled disposable and refillable. Pre-filled disposable cartridges include a specific filtration media sealed within. Their length-of-use is determined by the bulk filtration media and the amount of particulate to filter. Most refillable cartridges do not include filtration media. Housing-only products are ported enclosures that direct the flow of fluid through the filter element. Housing and filter assemblies are built-in cases or enclosures that cover and/or protect the filter assembly.
