(PDF) How copper-zinc water treatment systems work - Green Nest

(Water without these minerals is flat and can be aggressive, since water in its most natural state contains
minerals such as calcium and magnesium, picked up from the earth as it filters through rock strata.)
This scale reduction feature is ideal for cooling towers, hot water heaters, water lines, plumbing, ice-makers,
fountains, and other water-using equipment and appliances.
Removes Hydrogen Sulfide
Hydrogen sulfide is present in many U.S. water supplies. Recognized by its rotten egg odor and taste, it is a
poisonous gas that can, in large amounts, cause nausea and illness or death. It is also corrosive to metals,
which is especially serious in older plumbing systems that used lead-based solder.
When hydrogen sulfide passes through copper-zinc media, spontaneous oxidation removes the hydrogen
sulfide by creating zinc oxides and zinc sulfates. Zinc oxides and zinc sulfates are defined as food supplements
and nutrients by the Food and Drug Administration.
(During the copper-zinc filtration process, minuscule traces of zinc and copper are released into the water. In
proper amounts, both copper and zinc are necessary for healthy body functions. The trace amounts found in
CuZn filtered water are a small percentage of the minimum daily requirement for these minerals.)
Meets NSF, EPA Standards
In 1992, the Environmental Protection Agency ruled that copper-zinc, patented as KDF-, qualifies as a
mechanical device. This means the media imparts nothing harmful to the water. The National Sanitation
Foundation tested KDF® and found it to be in compliance with its Standard 61 for water treatment plant
applications and Standard 42 for aesthetic effects (taste, odor, chlorine reduction).
Removes Heavy Metals
Copper-zinc systems are excellent at removing heavy metals, often by electroplating them to the media's
copper-zinc granules. Under normal circumstances, CuZn filtration removes 90 to 98% of heavy metals,
including lead, iron, arsenic, and cadmium.
Works With Chlorination
When iron, hydrogen sulfide, or bacteria are present in large concentrations, CuZn filtration can be preceded
by chlorination and retention time. Chlorination oxidizes these contaminants and assists the copper-zinc media
in their removal. The copper-zinc, of course, then removes the chlorine and remaining contaminants from the
With carbon-only systems, this combination of chlorination and filtration is not efficient because the carbon is
quickly depleted when high levels of chlorine pass through it.
Works With Carbon