Frequently Asked Questions About Non-Chemical Iron Filtration Systems:
Q. Why are these systems
A. Many iron filters use greensand filter media which requires the use of potassium permanganate, chlorine or other chemicals. These filters remove iron and in some cases manganese without chemicals.
Q. How do they work?
A. These systems use Birm a type of iron filter media, or a blend of Birm, and calcium and magnesium filter media. As the water flows through, a reaction occurs where the dissolved oxygen and the dissolved ferrous iron compounds form an insoluble ferric hydroxide. After these ferric particles (also known as "rust") get trapped in the filter media, they are periodically backwashed out to drain, and the filter media is ready to filter again.
Q. Do these systems come
in different sizes?
A. Yes. The size of the systems is directly proportional to the flow rate of the water, in gallons per minute. The higher the flow rate, the larger the system required.
Q. Do these filters have
any special conditions to work properly?
A. Yes! There is actually a very specific set of conditions required. The water must have a pH of 7.0 or greater for Birm filters,and 6.5 or greater for Birm Blend filters to work properly. In addition, the dissolved oxygen content must be at least 15% of the iron or manganese content. The best applications are where the systems are installed after holding tanks (where dissolved oxygen is plentiful). In some cases, if a holding tank or storage tank is not used, then an air-injection venturi must be used to increase the dissolved oxygen. Additionally, no tannins, chlorine, oil or hydrogen sulfide (rotten egg odor) should be present.
Q. My water also has a very
bad smell of sulfur, is this a problem?
A. Yes. Do not use these iron filters when hydrogen sulfide (a natural toxic gas formed by iron and sulfur bacteria) is present. In these applications, use ozone, chlorinate or aerate in a tank to destroy the hydrogen sulfide. Generally, it is better to use chlorination or ozone, followed by greensand or greensand blend iron filters if hydrogen sulfide and/or iron bacteria is present.
Q. If I chlorinate first,
can I use this type of iron filter?
A. No. These iron filters should not be used if the water has a chlorine residual. De-chlorinate before the iron filter, or use the greensand type of iron filter.
Q. Are these systems big
A. No. The control valve uses only about 15 watts of energy to run the timer and backwash valve.
Q. I have very high manganese
(greater than .05 PPM), will these
iron filters remove manganese also?
A. Yes, but the pH must be between 8.2 and 9.0. One could raise the pH with soda ash or other methods to raise the pH, but it would be better to use a greensand filter to reduce manganese.
Q. What maintenance is required?
A. Under the right conditions there is little maintenance. If the iron is higher than 2.0 PPM and the hardness is greater than 150 PPM, then the control valve should be disassembled and cleaned once a year. If the pH is 6.8 to 7.2, and the alkalinity is low, then small amounts of magnesium oxide must be added to the filter periodically.
Q. Is there a pressure loss
through the system?
A. When properly sized, the system produces a very low pressure drop at service flow rates, usually around 5 psi.
Q. Can I route the backwash
water to my septic tank?
A. Yes. The backwash water is nontoxic and can be routed to the septic tank with no problem. It can also be routed to landscaping, although the backwash is usually very dark and orange, and will stain surfaces.
Q. How frequently do I have
to replace the filter media?
A. The filter media will last for 4 to 8 years depending on usage and conditions. It is easily replaced.
Q. Can I get assistance
in choosing an iron filter system
for my application?
A. Yes! You should first have your water tested, and then contact our technical staff for help on selecting the best iron filter system for your application.