Water Softeners
Generally used at the Point of Entry of the house or site. Removes the hardness minerals, calcium and magnesium by the ion exchange process, replacing them with sodium from salt.Does not greatly improve water for consumption. Often called "working water".
Water Conditioners
Generally POE; Can be just another term for a water softener but often includes other treatment medias such as activated carbon - mainly as a marketing tool. Typically overpriced.
Distillation
Generally POU; Removes a very broad spectrum of impurities, comparable to RO, when used in conjunction with activated carbon. Costly energy usage, cleaning and awkwardness of locating most distillers have prevented them from becoming widely accepted consumer products. High quality distillers are particularly good choices when water supplies are of unknown quality or where micro biological contamination is present. The distiller market is growing steadily while the product is being continually improved. Distilled water tends to have flat taste because it is boiled "to death".
Ozonation
Traditionally used for POE removal of iron, hydrogen sulfide and bacterial contamination. Recently POU products have come on the market for organic removal which ozone breaks down into harmless elements.Kills bacteria by adding an oxygen molecule.Ozone is basically an over excited oxygen molecule - 03 instead of 02. It is very aggressive and unstable. Once formed it does not last long and has a peculiar acrid smell.
Ozone is often used for micro biological control purposes in swimming pools. Some countries are currently experimenting with ozone for use as a disinfectant in public supplies. Like UV, ozone is primarily effective against micro-organisms, though it can also oxidize certain contaminants in much the same way as chlorine does.
Ultra-Violet Disinfection
Used for POU and POE as a means of controlling biological contamination. Inorganic an organic impurities are not affected. Products are being offered that combine carbon filtration and UV for more effective performance. Can be used as an adjunct to RO & Carbon filtration.
KDF
KDF is brass filings good for the removal of chlorine from shower water. Advantages are that it will not get destroyed in hot water (vs. carbon which will), so is good for shower filters. Disadvantages: As a drinking water system, it is not recommended. The brass filings could come out, and are not good to ingest, could stick into your insides!
The KDF will codify ( turn into a brick) in low TDS areas, like the SF Bay Area. hot water prevents this (like the shower & tub type KDF only units)
Silver Impregnation
Silver and other heavy metals (copper, zinc) deactivate bacteria (oligo-dynamic action) and creates a hostile environment for the growth of bacterial colonies. Silver impregnation does not kill or remove bacteria, but inhibits the growth of bacteria. Silver impregnation is used by NSA and some other companies, to inhibit the growth of bacteria. However, it will not actually do so past the first few servings of water. In order for it to inhibit bacteria growth for 6 months, it would have to have enough silver so as to be toxic to humans.
Iodinators & Brominators
As implied these units rely on the action of either iodine or bromine to kill bacteria.
These products are only effective against micro-organisms and have no ability to remove other contaminants. The disadvantage of these systems is that traces of iodine or bromine, which are both halogens, are usually present in the filtered water. As these chemicals are themselves pesticides and suspected carcinogens they should not be consumed.
De-ionization/ Deionization
The removal of all ionized minerals and salts (both organic and inorganic) from a solution by a two phase ion exchange procedure: First, positively charged ions are removed by a cation exchange resin in exchange for a chemically equivalent amount of hydrogen ions. Second, negatively charged ions are removed by an anion exchange resin for a chemically equivalent amount of hydroxide ions. The hydrogen and hydroxide ions introduced in this process unite to form water molecules. This process is also called demineralization by ion exchange. (WQA Glossary of terms).
Generally used at the Point of Entry of the house or site. Removes the hardness minerals, calcium and magnesium by the ion exchange process, replacing them with sodium from salt.Does not greatly improve water for consumption. Often called "working water".
Water Conditioners
Generally POE; Can be just another term for a water softener but often includes other treatment medias such as activated carbon - mainly as a marketing tool. Typically overpriced.
Distillation
Generally POU; Removes a very broad spectrum of impurities, comparable to RO, when used in conjunction with activated carbon. Costly energy usage, cleaning and awkwardness of locating most distillers have prevented them from becoming widely accepted consumer products. High quality distillers are particularly good choices when water supplies are of unknown quality or where micro biological contamination is present. The distiller market is growing steadily while the product is being continually improved. Distilled water tends to have flat taste because it is boiled "to death".
Ozonation
Traditionally used for POE removal of iron, hydrogen sulfide and bacterial contamination. Recently POU products have come on the market for organic removal which ozone breaks down into harmless elements.Kills bacteria by adding an oxygen molecule.Ozone is basically an over excited oxygen molecule - 03 instead of 02. It is very aggressive and unstable. Once formed it does not last long and has a peculiar acrid smell.
Ozone is often used for micro biological control purposes in swimming pools. Some countries are currently experimenting with ozone for use as a disinfectant in public supplies. Like UV, ozone is primarily effective against micro-organisms, though it can also oxidize certain contaminants in much the same way as chlorine does.
Ultra-Violet Disinfection
Used for POU and POE as a means of controlling biological contamination. Inorganic an organic impurities are not affected. Products are being offered that combine carbon filtration and UV for more effective performance. Can be used as an adjunct to RO & Carbon filtration.
KDF
KDF is brass filings good for the removal of chlorine from shower water. Advantages are that it will not get destroyed in hot water (vs. carbon which will), so is good for shower filters. Disadvantages: As a drinking water system, it is not recommended. The brass filings could come out, and are not good to ingest, could stick into your insides!
The KDF will codify ( turn into a brick) in low TDS areas, like the SF Bay Area. hot water prevents this (like the shower & tub type KDF only units)
Silver Impregnation
Silver and other heavy metals (copper, zinc) deactivate bacteria (oligo-dynamic action) and creates a hostile environment for the growth of bacterial colonies. Silver impregnation does not kill or remove bacteria, but inhibits the growth of bacteria. Silver impregnation is used by NSA and some other companies, to inhibit the growth of bacteria. However, it will not actually do so past the first few servings of water. In order for it to inhibit bacteria growth for 6 months, it would have to have enough silver so as to be toxic to humans.
Iodinators & Brominators
As implied these units rely on the action of either iodine or bromine to kill bacteria.
These products are only effective against micro-organisms and have no ability to remove other contaminants. The disadvantage of these systems is that traces of iodine or bromine, which are both halogens, are usually present in the filtered water. As these chemicals are themselves pesticides and suspected carcinogens they should not be consumed.
De-ionization/ Deionization
The removal of all ionized minerals and salts (both organic and inorganic) from a solution by a two phase ion exchange procedure: First, positively charged ions are removed by a cation exchange resin in exchange for a chemically equivalent amount of hydrogen ions. Second, negatively charged ions are removed by an anion exchange resin for a chemically equivalent amount of hydroxide ions. The hydrogen and hydroxide ions introduced in this process unite to form water molecules. This process is also called demineralization by ion exchange. (WQA Glossary of terms).
