What Do KDF Filters Remove from Water?
1, Free Chlorine
Chlorine in water is present as free chlorine and as total or combined chlorine. KDF removes only free chlorine, which is the one responsible for eradicating bacteria in water and oxidizing contaminants.
Free chlorine is also the element that causes many unwanted effects on hair, skin, eyes, and lungs. Therefore, it’s free chlorine that you want removed from your water supply.
Total or combined chlorine is chlorine that has reacted with other contaminants in water. This chlorine has little to no sanitising effect and no oxidizing ability.
If your water filter system combines both KDF and carbon media, you can get rid of both free chlorine and total chlorine.
KDF removes 99% of free chlorine, which essentially frees up activated carbon filters to better remove organic contaminants.
KDF can remove more than 90% of iron from your water supply by changing soluble ferrous cations into insoluble ferric hydroxide. The new by-product is strained through the filter bed, then periodically removed by backwashing.
3. Hydrogen Sulphide
Another contaminant that’s easily tackled by KDF is hydrogen sulphide. KDF changes hydrogen sulphide into insoluble copper sulphide, which again is strained through the filter bed and removed just like iron.
4. Heavy Metals
So far, the list of contaminants that KDF can remove has been impressive; however, the ability of this filter material to remove heavy metals like nickel, chromium, lead, mercury, etc. is even more impressive.
The mechanism through which KDF removes heavy metals is by bonding them to the surface of the filter granules.
5. Other Contaminants
Besides these contaminants, KDF can also tackle calcium carbonate and magnesium. KDF also inhibits the growth of bacteria, algae, viruses, and fungi.
This is an important advantage of filters containing KDF, because the inability of organic based media to inhibit the growth of bacteria is often why their service life is cut much shorter compared to antibacterial filters.