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Kinetic Degradation Fluxion (KDF-55) Water Filters

Kinetic Degradation Fluxion (KDF) is a high-purity copper-zinc formulation that uses a basic chemical process known as redox (oxidation/reduction) to remove chlorine, lead, mercury, iron, and hydrogen sulfide from water supplies. The process also has a mild anti-bacterial, algaecitic, and fungicitic, effect and may reduce the accumulation of lime scale. see technical bulletin...

KDF process media is used in pre-treatment and primary treatment applications to supplement or replace existing technologies in order to extend system life and to reduce heavy metal contamination, chlorine and hydrogen sulfide. It is often combined with other technologies to achieve superior overall results. Because of its effectiveness at higher water temperatures, it is often used on shower water filtration systems to remove chlorine and other contaminants.

The technology was developed by KDF Fluid Treatment, Inc. in the mid 1980s and was patented in 1987. KDF filter media meets EPA and Food and Drug Administration standards for levels of zinc and copper in potable water, and is certified by NSF International to its Standard 61 for drinking water.

 

How it Works Applications

In short, the KDF redox process works by exchanging electrons with contaminants. This "give and take" of electrons converts many contaminants into harmless components. During this reaction, electrons are transferred between molecules, and new elements are created. Some harmful contaminants are changed into harmless components. Free chlorine, for instance, is changed into benign, water-soluble chloride salt, which is then carried harmlessly through the water supply. Many heavy metals such as copper, lead, mercury and others, react and bond with the KDF medium's surface, thus being effectively removed from the water supply.

KDF filters are used most often in conjunction with an activated carbon filter. They prolong the life and increase the effectiveness of carbon filters by reducing chlorine build-up. They also supplement the activated carbon filters by removing heavy metals, something that carbon-based filters are not very effective at removing.

KDF is also frequently found in home showerhead filters because of its effectiveness at higher operating temperatures and flow rates.


KDF Copper-Zinc Media

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2

What Contaminants Does KDF Remove?

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4

KDF process media will reduce or remove chlorine, iron, hydrogen sulfide, lead, mercury, magnesium, and chromium, and may inhibit the growth of bacteria, algae, and fungi. Redox media remove up to 99% of water-soluble cations (positively-charged ions) of lead, mercury, copper, nickel, chromium, and other dissolved metals. While removal rates depend on a number of factors, more than 99% of chlorine is removed by KDF in home water treatment systems (90% in shower water filters due to high flow rate).

Note: Chart below is based on KDF-55 combined with basic activated carbon filter.

Bacteria

Bad Tastes
& Odors

Chlorine

Fluoride

Heavy
Metals

Hydrogen sulfide

Nitrates

Radon

Sediment

Viruses

VOC's

Mimimal

Removes

Removes

Mimimal

Removes

Removes

Mimimal

Reduces

Reduces

Mimimal

Removes


Removes= Effectively Removes         Reduces = Significantly Reduces         Mimimal = Minimal or No Removal

 

Advantages Disadvantages
  • effective removal of wide range of contaminants
  • cost effective
  • extend life and efficiency of carbon (GAC) filters
  • remains effective at higher water temperatures
  • best when combined with other filtration technologies, such as activated carbon, for full spectrum protection

Frequently Asked Questions About KDF Filtration

 

1. What is KDF?
Kinetic Degradation Fluxion (KDF) is a high-purity copper-zinc formulation that uses a basic chemical process known as redox (oxidation/reduction) to remove chlorine, lead, mercury, iron, and hydrogen sulfide from water supplies.

2. How does KDF Work?
In short, the KDF redox process works by exchanging electrons with contaminants. This "give and take" of electrons converts many contaminants into harmless components. During this reaction, electrons are transferred between molecules, and new elements are created. Some harmful contaminants are changed into harmless components. Others are electrochemically bound to the KDF media.

3. What Contaminants Does KDF Remove?
KDF process media works to reduce or remove chlorine, iron, hydrogen sulfide, lead, mercury, magnesium, and chromium. It may also inhibit the growth of bacteria, algae, and fungi. Redox media removes up to 99% of water-soluble cations (positively-charged ions) of lead, mercury, copper, nickel, chromium, and other dissolved metals. More than 99% of chlorine is generally removed.

4. Why is KDF used in shower water filters?
KDF is frequently found in home showerhead filters because of its effectiveness at higher operating temperatures and flow rates.

Granular Activated Carbon (GAC) and Carbon Block Filters

Carbon is a substance that has a long history of being used to adsorb impurities and is perhaps the most powerful adsorbent known to man. One pound of carbon contains a surface area of roughly 125 acres and can adsorb literally thousands of different chemicals. Activated carbon is carbon which has a slight electro-positive charge added to it, making it even more attractive to chemicals and impurities. As the water passes over the positively charged carbon surface, the negative ions of the contaminants are drawn to the surface of the carbon granules.

Activated carbon filters used for home water treatment typically contain either granular activated carbon (GAC) or powdered block carbon. Although both are effective, carbon block filters generally have a higher contaminant removal ratio. The two most important factors affecting the efficiency of activated carbon filtration are the amount of carbon in the unit and the amount of time the contaminant spends in contact with it. The more carbon the better. Similarly, the lower the flow rate of the water, the more time that contaminants will be in contact with the carbon, and the more adsorption that will take place. Particle size also affects removal rates.

Activated carbon filters are usually rated by the size of the particles they are able to remove, measured in microns, and generally range from 50 microns (least effective) down to 0.5 microns (most effective).

A typical counter-top or under-the-counter filter system has from 12 to 24 ounces of activated carbon. The most common carbon types used in water filtration are bituminous, wood, and coconut shell carbons. While coconut shell carbon typically costs 20% more than the others, it is generally regarded as the most effective of the three. All of our activated carbon filters use coconut shell carbon.

 

How it Works Applications

There are two principal mechanisms by which activated carbon removes contaminants from water; adsorption, and catalytic reduction, a process involving the attraction of negatively-charged contaminant ions to the positively-charged activated carbon. Organic compounds are removed by adsorption and residual disinfectants such as chlorine and chloramines are removed by catalytic reduction.

Activated carbon filtration is very common in a number of home water treatment systems. It can be used as a standalone filter to reduce or eliminate bad tastes and odors, chlorine, and many organic contaminants in municipal (pre-treated or chlorinated) water supplies to produce a significantly improved drinking water. It is also very commonly used as a pre-treatment as part of a reverse osmosis system to reduce many organic contaminants, chlorine, and other items that could foul the reverse osmosis membrane. 0.5 micron carbon block filters are commonly used to remove cysts such as giardia and cryptosporidium.

 

What Contaminants Does Carbon (GAC) Remove?

Activated carbon filters remove/reduce many volatile organic chemicals (VOC), pesticides and herbicides, as well as chlorine, benzene, trihalomethane (THM) compounds, radon, solvents and hundreds of other man-made chemicals found in tap water. Some activated carbon filters are moderately effective at removing some, but not all, heavy metals. In addition, densely compacted carbon block filters mechanically remove particles down to 0.5 micron, including Giardia and Cryptosporidium, turbidity and particulates. Also, very little iron or manganese will pass through these higher quality activated carbon filters although a manganese greensand iron reduction filter is generally preferred to remove these contaminants as the effectiveness of carbon filter against iron and manganese is generally short-lived if the contaminant concentration is high.

GAC does not remove sediment / particulate material very well, so they are often preceded by a sediment filter. Sediment pre-filters also prolong the activate carbon cartridge life by eliminating gross contaminants that would otherwise clog the activated carbon thereby reducing the surface area available for adsorption.

Bacteria

Bad Tastes
& Odors

Chlorine

Fluoride

Heavy
Metals

Hydrogen Sulfide

Nitrates

Radon

Sediment

Viruses

VOC's

Mimimal

Removes

Removes

Mimimal

Reduces

Removes*

Mimimal

Removes

Reduces

Mimimal

Removes


Removes= Effectively Removes         Reduces = Significantly Reduces         Mimimal = Minimal or No Removal

* At high contaminant levels, filter life will be reduced significantly. Manganese greensand (whole house iron reduction filter) or KDF filter is recommended for Hydrogen sulfide.

 

Advantages Disadvantages
  • most effective removal of organic compounds including VOCs, radon, and chlorine (including cancer-causing by-product trihalomethanes)
  • very cost effective
  • GAC - following scheduled filter replacements and reversing of the cartridge is important to eliminate the possibility of "channeling" which reduces the contact between the contaminant and the carbon and therefore reduces efficiency, and the accumulation of bacteria in the filter

 

Products w/ Carbon Filters Typical Maintenance

Virtually all of our home water purification systems include activated carbon block filtration.

Note: All Aquatic Smart products use the highest quality coconut shell carbon.

Activated carbon filters require very little maintenance, however, it is very important to ensure that filter replacement schedules are followed to ensure proper filtration at all times. Do not wait for bad tastes and odors to return to the water before deciding the filter needs replacement as this is an indication that the filter is no longer able to completely remove contaminants and that it has surpassed its service life.

Frequently Asked Questions About Activated Carbon Filtration

 

1. What is Activated Carbon?
Carbon is an extremely porous material that attracts and holds a wide range of harmful contaminants. Activated carbon is carbon which has a slight electro-positive charge added to it, making it even more attractive to chemicals and impurities. As the water passes over the positively charged carbon surface, the negative ions of the contaminants are drawn to the surface of the carbon granules.

2. What forms does it come in?
Activated carbon filters used for home water treatment typically contain either granular activated carbon (GAC) or powdered block carbon (carbon block).

3. Which is generally better, GAC or carbon block?
Although both are effective, carbon block filters generally have a higher contaminant removal ratio and are more resistant to channeling.

4. Are all carbon filters equally effective?
No. Activated carbon filters are usually rated by the size of particles they are able to remove, measured in microns, and generally range from 20 microns (least effective) down to 0.5 microns (most effective). The two most important factors affecting the efficiency of activated carbon filtration are the amount of activated carbon in the unit and the amount of time the contaminant spends in contact with it. The more carbon the better. Particle size also affects contaminant removal rates. The most common carbon types used in water filtration are bituminous, wood, and coconut shell carbons. While the coconut shell carbon typically costs 20% more, it is generally regarded as the best of the three.

5. Can I use taste and flow rate to determine when to change the filter?
No. These are very poor methods of monitoring your water filter for maintenance. Once the bad tastes have returned, it is already far too late - contaminants have passed through the filter and into your drinking water. A carbon cartridge may be able to control taste and odors long after the carbon has lost its ability to effectively reduce other toxic contaminants. You should always follow the manufacturer's filter replacement schedule to ensure optimal filtration.

6. What is Backwashing and do you recommend it?
Backwashing is the process of forcing water through a filter in the wrong direction to unclog the dirt and sediment which has blocked the filter. Backwashing is a common practice for certain whole house and commercial units which are treating large volumes of water for utility purposes and shower filters but it is not a recognized practice for small point of use drinking water systems.

 
 
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