Which System Do I Need to Remove Iron?
That's a question we get a lot, and the question is not easily answered because it depends upon a number of issues, including the following:
- iron levels of your water;
- the pH of the water;
- the levels of manganese and/or sulfur in the water;
- whether the water has any iron-reducing bacteria (IRB) or sulfate-reducing bacteria (SRB);
- how much water is needed a day;
- is it for just household use or is it being used for irrigation, and if so, how much water is needed a day; and
- how effective do you want it to be?
Iron stains at levels above 0.3 ppm (parts per million), so for a system to be effective, it needs to remove the iron to below 0.3 ppm. Every application is different, but I will give you a few guidelines as to what might be best for you.
The pH needs to be above 6.6 and there should be NO IRB or SRB in the water supply. Manganese dioxide media is often used for this purpose. First of all, if you are using a media that is composed primarily of manganese dioxide and not using some type of oxidizer, then the pH needs to be above 6.6 and there should be NO IRB or SRB in the water supply. Manganese dioxide media is typically called Pyrolox, Adox, Filox, Catalox and other names.
Iron filters that used manganese greensand regenerated by potassium permanganate used to be very popular, but were in fact, very troublesome and unpredictable. Forget iron filters. PERIOD! My advice is to also forget Birm, which is a media coated with a very small amount of manganese dioxide.
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Hydrogen Peroxide System - Fusion OXi[/caption]
The manganese dioxide medias can work very well, but many water supplies contain organics and IRB and SRB that impeed it's ability to work properly. At US Water, we prefer to use technology that is scientifically sound and sustainable. The technology that we trust the most is our OXi system which utilizes hydrogen peroxide for the eradication of iron or rust, sulfur, which is hydrogen sulfide odor, and manganese. It can truly be called an Eradicator because it TOTALLY removes iron, sulfur and manganese. Properly sized, an OXi-Gen Hydrogen Peroxide System from US WATER is THE MOST EFFECTIVE METHOD for removing iron, rust, sulfur, hydrogen sulfide and manganese and the rotten-egg odor from your water supply. Hydrogen Peroxide is not a hazardous chemical - to the contrary, hydrogen peroxide or H2O2, is composed of the elements of water: Hydrogen and Oxygen. If you have extremely high levels of iron, hydrogen peroxide is very effective. The drawback to it is the annual peroxide cost which can run from $200 to several hundred dollars a year, depending upon how much water you use.
There is nothing foreign or chemical added to the water supply. Unlike chlorine, hydrogen peroxide requires no contact time and the reaction or oxidation of iron, rust, sulfur, manganese and hydrogen sulfide is immediate. The Oxi-Gen Hydrogen Peroxide System
is the answer to practically any iron, rust, sulfur, hydrogen sulfide and manganese problem. With hydrogen peroxide or H2O2 as it is called, you can always predict for a certainty that it will always work, even with iron bacteria. There really is no limit as to how much can be removed, but if the iron is over 20 ppm, you need to realize that there will be a lot of iron sludge precipitate left behind to deal with. Generally, we would recommend the use of H2O2 in residential applications, not high usage irrigation applications.
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infusion Air Oxidation System[/caption]
A new development in iron/sulfur and manganese removal is a system that uses the oxygen in the air as the oxidizer. This is called the infusion chemical-free iron-filter system
, which needs to backwash everyday to replenish the air in the media tank. This is also a system that would be for low-volume residential applications (maybe 500-600 GPD maximum). While the infusion system can handle high amounts of iron and sulfur, it is best applied to water that is not higher than 8.0 to 10.0 ppm of iron or sulfur. I know one company that says their air system will remove up to 66 ppm of sulfur, but that is really pushing the envelope. Where you get into trouble in water treatment is when you over-apply whatever technology you are using. I believe is systems that are on the larger size, so that you have more contract time. Proper filtration is a product of adequate contact time. I also believe that for a technology to be sustainable and practical, you need to be conservative in your estimates.
If irrigation is at issue, we sometimes use ADOX which is a manganese dioxide-based media, or Greensand Plus. I prefer the Greensand Plus as it is more predictable. We usually feed a small concentration of chlorine ahead of the Greensand Plus or inject it during backwash to keep the media activated and in tip-top operating condition. There are lots of options and ways of treating iron and many applications are different. If you are unsure what method is best for you, feel free to contact one of our Certified Water Specialists at US Water Systems.