You know “iron water,” the stuff that looks clear when it comes out of the well, but soon colors everything it touches a dull orange? It’s the arch-enemy of many municipal water facilities, commercial poultry production companies, produce processing companies, and anyone else who would like to utilize large quantities of well water, but can’t because of high iron concentrations.
The problem with iron is that there was never a way to remove it without using massive filtration systems and even more massive settling tanks. We’re talking a large footprint, a half acre or more for large volume systems to improve well water quality, which just isn’t practical. That’s because the only way to get the iron out of the water is to oxidize it, and to do that, you have to introduce oxidizing chemical agents (some of which make it undrinkable) or let it set in the open air–or aerate. As it oxidizes in an open-air environment, the dissolved particles come together over time and form larger particles, which can be “settled out,” filtered out, or otherwise dealt with.
There are groundwater and surface water purification facilities in the United States that do just that; treat the water with chemicals and then allow it to aerate in HUGE settling tanks, so the iron can be removed through gravity and filtration.
Ozone to the rescue
In my recent water conservation work with a commercial poultry production facility, I was asked to explore technologies that would allow them to use water from a well that had so much iron in it as to be basically useless–with concentrations ranging from 6 to 9 parts per million (the national limit for drinking water is 0.3 parts per million).
Since oxidation is the secret to transforming iron from its ferrous (dissolved) state to a ferric (colloidal/larger particles that can be filtered out) state, ozone was a natural place to start. Ozone is, after all, an oxygen molecule with an extra atom–O3 instead of the O2 we breathe in the air.
The first thing we discovered was that O3 does a much faster job of oxidation than O2, but that the freshly formed particles are smaller than those formed during the longer oxidation periods required by other conventional technologies. We needed a finer filter.
We found one that has been used with great success in other applications, but that has rarely been tried in this one. The filter automatically cleans itself and removes particles as small as 3 microns–drinking water standard. It also handles the water volumes required by large industrial users like produce processing facilities and commercial poultry production facilities. Bingo.
We tested a portable prototype of our “iron water” treatment system at the poultry production facility, then invited the local and state health departments to test the well water quality. We not only reduced the iron content to undetectable levels, but passed every drinking water test with flying colors. The iron water treated with our system was deemed as “potable equivalent.” Our entire iron water treatment system is the size of an average office, rather than the usual half acre. Once set up, it requires almost no maintenance, and in addition to iron, it removes manganese, magnesium, radon, sulfides, hydrogen sulfide gas, and probably a whole host of other pollutants we have yet to quantify through laboratory analyses.
It’s the smallest, fastest, most economical high volume iron removal/well water quality purification system in the world, and it’s AWPI’s latest solution to the global water crisis.