State-of-the-Art Membrane Filtration of Water
One of the most advanced technologies used in water filtration, membrane filtration utilizes a semi-permeable membrane that either functions as a very fine filter (e.g., ultrafilters, microfilters) or a highly technical process that utilizes various types of filters comprised of semi-permeable membranes. Microfiltration and Ultrafiltration remove minute particles that are suspended within the water, including bacteria and even viruses. Ultrafiltration can separate one liquid from another, for example by removing oil from water. Reverse osmosis and nanofiltration rely on semi-permeable membranes that can remove tiny particles as well as dissolved minerals from water.
The terms "pure", "purified" and "water for injection" are used within the water treatment industry to describe water that meets strict regulations set by the Food and Drug Administration (FDA) as defined in the US Pharmacopeia. Membrane filtration typically plays a key role in preparation of such very high purity water. Other standard metrics and guidelines defining water purity are set by various governing bodies, agencies, and regulatory authorities. Purity standards for ultrapure water include those set by a number of organizations, such as the USP, ASTM, CAP, NCCLS, ANSI and AAMI. To meet these stringent guidelines, it is frequently necessary to use membrane filtration technology to remove unwanted chemicals or other particles or organisms from the water.
Modern Membrane Filtration Water Technology
The criticality of ultra filtered or ultrapure water has increased over the years, as more applications for this extremely pure and clean standard of water have emerged. For example, although potable water may be treated and purified with agents such as chlorine, it may still contain harmful organisms such as Giardia and Cryptosporidium that happen to be resistant to chlorine treatments. To assure more effective removal of these tiny organisms, many States now require membrane filtration (ultrafiltration or microfiltration) be part of new treatment facilities.
Using Ultrafiltration to Ensure System Performance
Reverse osmosis water treatment systems often depend on ultrafiltration or microfiltration for the effective removal of foreign particles that may also clog or foul the extremely small pores within reverse osmosis membranes. For the same reasons, an ultrafiltration membrane may be used to minimize the density of silt in water, or as a preliminary step in a phased process of treating water that will later be run through another level of purification.
Other Commercial Applications for Membrane Filtration of Water
Ultrafiltration treatment is also highly valuable to private sector companies and industries – wastewater treatment plants, for instance. Ultrafiltering is used in many areas of the pharmaceutical and medical industries as well. Kidney dialysis is an area of health care that depends upon modern microfiltration and ultrafiltration equipment and technology. Ultrafiltration is also used in the biotech and semiconductor manufacturing industries.
For years companies and regulatory agencies have relied upon highly advanced membrane-based water treatment systems and process equipment. Modern-day membrane systems have become even more useful and valuable, thanks to today’s sophisticated and economical membrane filtration systems.