Water-filters:How can You benefit?
Water-filters come in different types and are made of various ingredients. There is no absolute commercial water purifier for home use, capable of providing the best and safest drinking water at minimum cost. For best performance it is essential that a multi stage process be used to filter out a wide range of contaminants. Nevertheless there are a few types of home water purifiers that do an acceptable job of improving satisfactorily the quality of tap water supplied by a municipal service. Only this application is considered within this page. This presentation does not deal at all with the case of domestic purification of contaminated water from raw water repositories open to uncontrolled pollution. Among the common Water-filters purifiers one can distinguish a few basic principles characterizing their operation. Check the following offer: Carbon Filtration The most common type of Water-filters is probably that based on carbon filtration systems, and frequently selected styles are point of use countertop and under-the-sink systems. Their effectiveness decreases with volume of treated water and time, and the cartridges must be replaced at regular intervals. Charcoal Water-filters also called activated carbon, activated charcoal or activated coal filters or purifiers, are made with an extremely porous form of carbon that provides a very large surface area for adsorption or chemical reactions. Granular carbon filters and carbon block systems use the same process of contaminant removal, adsorption, by which the contaminant bonds chemically or physically to the surface of the filter medium. Activated carbon is recognized by the U.S. Environmental Protection Agency (EPA) as the best available technology for filtering Volatile Organic Compounds (VOCs) and Trihalomethanes (THMs). Sometimes, for purifications of domestic water, silver loaded activated carbon is used as an adsorbent due to its anti microbial/antiseptic properties. Water-filters can be characterized by the maximum size of pores they display. Those rated at 1 micron (one thousandth of a millimeter) or less will effectively block Cryptosporidium and Giardia, known and dangerous parasites. Ceramic Water-filter purifiers Ceramic water filters are an inexpensive and effective, if slow, type of water filter, that rely on the small pore size of ceramic material to filter dirt, debris, and bacteria out of water. The filter lets only water and smaller contaminants pass through to the clean side, blocking the passage of anything larger than a water molecule. The two most common types of ceramic water purifiers are pot type and candle type filters. The systems consist of a porous ceramic filter element of a fossil substance made of tiny silicon shells, remnants of one celled algae called diatoms, that sits on top of a plastic or ceramic receptacle. Some ceramic water filters are treated with colloidal silver to further incapacitate bacteria and prevent the growth of mold and algae in the body of the filter. Contaminated water is poured in the filter and passes through it into the receptacle below that may be fitted with a tap. Contaminants which are larger than the minute holes of the ceramic structure will remain in the top half of the unit, which can be cleaned and restored by brushing the inside of the top section with a soft brush and rinsing it out. Some ceramic filters, which do not remove chemical contaminants, use also active carbon which absorbs compounds such as chlorine. Filters with active carbon need to be replaced periodically. Reverse Osmosis (R.O.) This process lets water under pressure pass through a semi permeable membrane with a very fine pore structure. The membrane rejects certain contaminants of larger molecular size, minerals and a large fraction of the polluted water. The passing portion of water is stripped of inorganic compounds and of trace minerals. However many synthetic chemicals, such as small size molecules of herbicides and pesticides can pass the membrane. Therefore a carbon filter should always follow an R.O. system. R.O. requires energy for providing water pressure, and extensive maintenance. The process is slow, producing low quantities of filtered water per hour and is wasteful of energy and of rejected contaminated water. Point-of-Use Distillation Heated Water vaporizes, rises and transfers to a cooling chamber, where it condenses back into a liquid. This process separates water from inorganic compounds like lead, calcium, magnesium, etc. Distilled drinking water affects the balance of minerals in the body, and is more acidic. Healthy dissolved minerals in the water are more natural than pure water, and serve an important function in supporting the body's immune system and metabolism. Distillation also destroys bacteria. It not very effective at removing organic chemicals, since they typically vaporize at a lower temperature than water does and are transferred in the steam. A distiller should always be used in conjunction with a carbon filter. Pitchers and Carafe-Style Filters These types of filters have emerged as cheap alternatives to bottled water. Keeping in mind that any filter is better than no filter, these products are by far the least effective and the most costly to use. Certain types may have the additional advantage of reducing the hardness of water and the carbonate layer resulting on heating coils. Because of the small size of these cartridges, they have very limited effectiveness and a low capacity. While pour-through filters do offer a slightly improved alternative to tap water, they by no means offer the quality, convenience and economy of other systems like those considered in our page on Filter Advice. Ultraviolet Water Sterilizers A lamp producing Ultraviolet (UV) radiation is emitted through clear, pre-filtered, particle-free water. This UV light is extremely effective in killing and eliminating bacteria, yeast, viruses, molds and other harmful organisms. UV is used in industry and hospitals to treat water. Must be used in conjunction with sediment and carbon filters to create pure drinking water, because sterilization has no effect on inorganic or chemical contaminants. Conclusion It has been made clear, hopefully, that only integrated Home Water-filter systems, conforming to suitable standards like NSF Standard #53, have the capability to provide effective purification of municipal tap water to make it safe, healty and tasteful. To compare home water purifiers Readers are invited to find more information on suitable Water-filters in our page on Filter Advice. Water Purification Water Quality Filter Advice For any questions on these arguments please Contact Us. (Sponsored Links) Could you make some use of a little extra income? POWERED BY:
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