The two main filtration medias used in CuZn Water Filters are the highly rated Activated Acid Washed Coconut Shell Carbon and their patented FilterFoam KDF copper-zinc media for all shower, bath ball, countertop, under-counter, travel and larger whole house systems. A variety of other medias are used to treat specific contaminants like chloramines, fluoride, nitrate, arsenic and hardness, like ion exchange resins, mixed bed cation, activated alumina, KDF85 and catalytic carbon.
For their new smaller whole house systems, CuZn combined the KDF and carbon media into a new, patented fast flow GRA (Granular Radial Axel) cartridge to remove chlorine, iron, lead and other heavy metals, bacteria and other micro-organisms, hydrogen sulfide, disinfection by-products (DBPs), trihalomethanes (THMs), herbicides, pesticides and hundreds of other organic and inorganic contaminants from the water supply. The GRA cartridge also reduces scale and hardness, but retains minerals to balance water. The GRA cartridge is included in specialty tanks that treat chloramines, fluoride, nitrate, arsenic and hardness.
Carbon has a long history of being used to absorb impurities and is perhaps the most powerful absorbent known to man. One pound of carbon contains a surface area of roughly 125 acres and can absorb literally thousands of different chemicals. Carbon typically comes either as granular activated carbon (GAC) or powdered block carbon. Although both are effective, carbon block filters generally have a higher contaminant removal ratio. The most common carbon types used in water filtration are bituminous, wood and coconut shell carbons. While coconut shell carbon typically costs 20% more than the others, it is generally regarded as the most effective of the three (CuZn uses coconut shell carbon).
Activated carbon is carbon that has a slight electro-positive charge added to it, making it even more attractive to chemicals and impurities. As the water passes over the positively charged carbon surface, the negative ions of the contaminants are drawn to the surface of the carbon media (CuZn uses activated carbon).
Activated carbon filters are usually rated by the size of the particles they are able to remove, measured in microns, and generally range from 50 microns (least effective) down to 0.5 microns (most effective, but clogs the fastest). Activated carbon pores can be divided into three general micron sizes: Micro-pores (diameter in the range of less than 2 nm), Meso-pores (diameter in the range of 2 - 25 nm), and Macro-pores (diameter in the range of above 25 nm). NOTE: Cuzn offers 20, 5 and 1 micron models, the most practical sizes for filters used for city and well water.
CuZn uses dedusted, acid washed granular coconut shell activated carbon, which comes from coconut shell that has undergone a steam activation process to create its activated carbon form. During activation, it creates millions of pores at the surface of the carbon thus increasing the total surface area. Coconut shell carbon is rated by the iondine level which measures how well it absorbs contaminants, ranging from a low of 400 to a high of 1200. CuZn's acid washed coconut shell activated carbon is rated at 1100.
Coconut shell carbon has mainly micro-pores to meso-pores and due to its unique distribution of pore diameter, coconut shell activated carbon is very popular in the gas phase purification and potable water purification industries. Coconut shell carbon has a superior level of hardness that makes it cleaner than most other carbons and gives it longer life expectancy. This, combined with its high activity level, makes coconut shell carbon well suited for use in any kind of carbon-based filtration system.
Activated carbon filters remove/reduce many volatile organic chemicals (VOC), pesticides and herbicides, as well as chlorine, benzene, trihalomethane (THM) compounds, radon, solvents and hundreds of other man-made chemicals found in tap water.
Carbon filters are NOT generally successful at removing dissolved inorganic contaminants or metals such as minerals/salts (hardness or scale-causing contaminants), antimony, arsenic, asbestos, barium, beryllium, cadmium, chromium, copper, fluoride, mercury, nickel, nitrates/nitrites, selenium, sulfate, thallium and certain radio nuclides. That's why CuZn includes their patented FilterFoam KDF filtration media in most of their models.
The combination of copper and zinc is patented under the trade name KDF. KDF55, in water treatment systems, removes chlorine, some iron, lead, bacteria, some hydrogen sulfide, and hundreds of other problem contaminants from the water supply. It also reduces scale and hardness. KDF85 in water treatment systems removes chloramines, heavy metals, iron and hydrogen sulfide.
The EPA has certified KDF as a pesticidal device because of KDF's ability to control bacteria, algae, fungus, mold and legionella through the natural redox process without the release of harmful ions. KDF has also been certified by the New Jersey EPA as Best Available Technology for mercury removal from contaminated wells and other water. KDF media is recyclable, non-hazardous material. It remains active longer than other media -- i.e., carbon -- and can be effectively backwashed to further increase media life.
Works Alone or in Combination
Copper-zinc can be used alone or in concert with traditional treatment processes (such as carbon and reverse osmosis) for a synergistic blend of media. Copper-zinc assists traditional treatment by extending the life of carbon or reverse osmosis membranes, by maintaining a bacteriostatic environment inside the filter, and by leaving a residual of copper and zinc hydroxides in the treated water to discourage bacterial growth.
Lasts Longer than Carbon
With a life span of 10 to 20 times that of carbon, copper-zinc is the most efficient, longest lasting and lowest maintenance filtration media on the market. It removes the weak link in most water treatment systems: the monitoring and maintenance and component replacement required by these systems.
CuZn Water's patented FilterFoam KDF copper-zinc disks have several advantages over granular KDF. Their disks eliminate the need for backwashing, conserve water, eliminate the need for cartridges and plastic waste, and are even recyclable, and reduce compaction. When granulated KDF media compacts, it can harden at the bottom of the tank, becoming impossible to remove, meaning the tank will need to be replaced. CuZn's KDF FilterFoam disk are easier to use, maintain and refill than cartridge systems, plus they offer greater surface area for better performance.
Filters by Catalytic Action
CuZn media functions by catalytic action, using the age-old redox (reduction-oxidation) principle of dissimilar metals. Water containing dissolved oxygen, minerals and organic materials enters a bed of the copper-zinc alloy, with the copper becoming the cathode and the zinc becoming the anode. The space between each granule of alloy in the media bed becomes an electrolytic cell. The water and contaminants act as electrolytes. As contaminants and oxygen pass through, a reaction takes place, causing zinc hydroxides and copper hydroxides to form in controlled amounts. These controlled releases of copper and zinc oxides (chelatable by the body) are carried into the filtered water and provide hostile conditions for algae, fungus, and bacteria growth.
Eliminates Hard Crystalline Scale
Within a water system, calcium and magnesium can adhere to plumbing and water appliances by forming crystalline scale structures. These become hard, interfere with heat transfer and eventually cause loss of water flow and pressure. Copper-zinc reshapes these hardness ions so they cannot adhere to each other or to the inside of plumbing. Instead the calcium and magnesium ions remain soluble in the water, thus reducing scale while adding life to the water. 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.
NOTE: 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.
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. KDF85 is best for hydrogen sulfide.
(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 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 water. 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.
Water filtration technology has reached the point where using a combination of treatment methods allows a system approach to water quality problems and provides better water quality. Many CuZn systems use carbon filtration in concert with copper-zinc filtration to treat water with high levels of organic contaminants which carbon is excellent at removing. Because the carbon is not removing chlorine (the copper-zinc does this before the water reaches the carbon) and because the copper-zinc provides a bacteriostatic environment, carbon's life is greatly increased. (Bacterial fouling of the carbon media is a serious problem in carbon-only water filtration and requires frequent media replacement.)
CuZn Water Filtration Systems, Inc. has specialized in this approach since its start in 1987 by combining the most advanced copper-zinc technology with traditional filtration methods to solve a broad spectrum of water problems.
CuZn Water Filters are made in the U.S.A. and are Duty FREE to Canada.
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