How do you remove rust (iron) from your water?
A WATER SOFTENER CAN REDUCE IRON TO BELOW THE THRESHOLD OF STAINING, BUT IT CAN NOT TOTALLY REMOVE IT!
Under some circumstances, a water softener will work for a while, but the resin bed will gradually become fouled with iron over months or years, decreasing its efficiency at removing the iron.
To totally remove iron, one must utilize the following: (1) Oxidation and filtration; or (2) Sequestration using polyphosphates.
POLYPHOSPHATES - We will discuss sequestration of iron with polyphosphates first. Sequestration of iron with polyphosphates does not remove it from the water supply, but keeps the iron in solution, so that it does not produce stains. This is often used when individuals or businesses want to keep the iron from staining in irrigation systems. It is accomplished by injecting a small amount of polyphosphate into the water, typically with a chemical injection pump and a solution tank containing a supply of polyphosphate.
However, it is not perfect in removing iron, as evaporation of the water can still leave an iron residue and the iron often precipitates when the water is heated. Results may very dramatically with sequestration, depending upon a variety of factors, not the least of which is water chemistry.
OXIDATION - Almost any concentration of iron can be oxidized by feeding an oxidizer such as chlorine, ozone, pottasium permanganate, hydrogen peroxide or even oxygen into the water supply. The oxidizer reduces the iron to a small particle (precipitate), which is then mechanically filtered from the water, typically by a backwashing filter with a dense media containing carbon or materials.
In my thirty-plus years of experience, I have personally tried every method known to man to remove iron. Today, I primarily use hydrogen peroxide, as it is a much better oxidizer of iron than either chlorine or potassium permanganate and does not leave excess air in the water like oxygen systems. Unlike chlorine, hydrogen peroxide is simply hydrogen and oxygen and produces no harmful chlorination byproducts.
A hydrogen peroxide system consists of a chemical injection pump, solution tank, in-line static mixer, and a backwashing filter to remove the oxidized iron. I prefer the hydrogen peroxide system because it completely removes iron and sulfur with totally predictable results. It is my opinion that other methods are not as predictable or reliable in function. A hydrogen peroxide system will remove 100% of the iron. PERIOD!
For homebuilders that build large custom homes with irrigation systems on iron-bearing waters, the hydrogen peroxide system will totally eliminate any staining in irrigation systems, and throughout the home, for that matter. Additionally, a water softener will not have to work nearly as hard once the iron is completely removed. This is not to say that other methods can't work. I am just stating my opinion based upon my extensive experience in treating problem water.
99 Comments
We would like to treat our well with hydrogen peroxide, and not just filter it at the house. Does anyone know how much we would need to add to the well to do this?
If you are using 7% H2O2, use 1 gallon per 100 feet of well depth. If you are using 35% (be careful) and use 1 quart per 100 foot of well depth.
Where do I get this ind of system? How much does it cost? How much does it cost to operate? I think your article is very good.
US WATER SYSTEMS sells this product. Go to https://www.uswatersystems.com
Can Mark (or someone) give me more complete instructions about adding Peroxide to well water to eliminate iron? How long do you leave the Peroxide in the well? Should I flush it directly outside, or let the water go through the house? Is there any danger to septic systems? Etc.? Thanks.
Arthur, I would not really recommend “dumping” H2O2 into the well. You can “shock” chlorinate a well, but Hydrogen Peroxide needs to be fed on a continual basis.
Mark, I’m a bit confused. You write that you wouldn’t recommend dumping H2O2 into a well, but you seemed to be recommending it in your Dec 1 letter, above. In any case, if that’s a bad idea, how do you shock chlorinate a well? How long do you leave the Chlorine in the well? Should I flush it directly outside, or let the water go through the house? Is there any danger to septic systems? Etc.? Thanks again.
Mark, Arthur again. I just found a lot of instruction on “shock chlorination.” The thing is, I have a lot of iron in my well, but I don’t think I have bacteria. No smell, just brown colour and grit from time to time. Any suggestions? Thanks.
Arthur, Hydrogen Peroxide needs to be injected into a mixing chamber just ahead of your pressure tank. A peristaltic pump is used to inject it from a container of the H2O2. It immediately oxidizes the iron, manganese and sulfur ,which is then removed with a backwashing filter containing Centaur catalytic carbon. This system does a great job of eradicating the iron. If you want to “shock” chlorinate a well, you should use a chlorine disinfection kiy such as the one found here: http://tinyurl.com/3by58f Follow the manufacturers’ directions and it should be fine to doe on an occasional basis (once or twice a year). Shock chlorination is only a temporary fix and you shouldn’t run any more chlorine than necessary into your septic tank. If you need to do so, flush some extra septic tank “bacteria” down the toilet to compensate.