Regular water softeners for iron and manganese removal

At what levels of iron and/or manganese does one need to utilize specialty filters or resin units. I understand regular ion exchange softeners will remove some levels of iron/manganese. Is there a cartridge unit for iron/manganese removal?

Answer: This is a difficult questions to answer precisely; it really depends on the specific water chemistry, type of iron present, and overall design of the water softener.  However, a standard water softener can remove up to 2 approximately 2 mg/l iron, assuming the iron is present only in ferrous (dissolved, clear-water) form.  Again, depending on water chemistry and specific design (like up-flow, twin tank, or softeners equipped with a turbulator), higher levels of iron can be removed using a water softener.  We generally recommend using a fine mesh resin, and adding a resin cleaning feeder to the softener when levels of iron are present that exceed 2 mg/l.  You can take a look at our Iron Eliminator add-on package that features this design.  When iron is present as both ferrous & ferric (particulate, “red water”) iron, iron removal efficiency is significantly reduced, and the softener should be designed correctly for the specific application.

Regarding manganese removal, one of the best methods for removing manganese is with use of a water softener, however, pH must be above 7.0 units.  In addition, a resin cleaner like Res-Up or Pro-Res must be used for effective removal of the accumulated manganese, or resin bed failure may result.

If you have the specifics of your application that includes a complete water analysis, number of residents in the home, and pipe diameter, we can help you further.  If you need a water analysis, we will provide one at no charge to you.  By the way, there are cartridges available that will remove iron & manganese – but these are generally not used for whole-house application.

Comments

  1. Indeed, the removal of Iron and Manganese is a challenge for all working in the field. So much so that it can provoke some very interesting debates on how best to treat this type of water.

    Iron and Manganese are usually found together in application where underground wells are used as a source. In my experience, we always find them in a ratio of 2:1 (Fe:Mn) and sometimes, 3:1. But that’s besides the point.

    In larger application that use Reverse Osmosis, we direct treat the feed water. No pre-treatment. We first make sure that the feed stream is well isolated so no oxygen is introduced and we also lower the pH, making the environment reductive and hence, keep the Iron and Manganese in solution. But doing so, the RO membranes have no difficulty rejecting the metals.

    For a residential applications, this can be too combersome and hard to maintain. On top of that, you need to adjust the pH of the permeate in order to avoid drinking very acidic water.

    I’m glad you guys brought this subject up because I had no idea on how to solve this issue on a small scale.

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