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The Effects of Carbon Filters on Water

All carbon filters use activated carbon, usually derived from charcoal. The term "activated" means that the carbon has been pulverized, oxygenated and otherwise processed to maximize surface area, pores and absorption. The terms activated carbon and activated charcoal are synonymous. There are several types of activated carbon filters, including granular, powdered, extruded, polymer-coated and impregnated.

  1. PAC

    • The type of carbon filter used in water treatment is powdered carbon and is referred to as PAC, or powdered activated charcoal. Granules are no larger than 1.0 millimeter, with diameters averaging between .15mm and .25mm. As an illustration of the increased surface area carbon has when activated, ten grams of PAC have a surface area the size of a football field.

    Effects on Water

    • Carbon, one of the elements in the Periodic Table of Elements, is known as the organic compound, because it is basic to living organisms. The field of study known as organic chemistry is essentially the study of the properties of carbon. One of those properties is that organic matter chemically attaches to carbon atoms when it comes in contact with them. Thanks to the massive surface area and billions of pores available in activated carbon, passing water through activated carbon filters removes organic material, such as feces, urine, food particles, earth, bacteria and viruses. Carbon also absorbs chlorine.

    What Carbon Does Not Remove

    • Carbon has no filtering attraction for many chemicals, including nitrates and sodium. For this reason, carbon filtering of water on an industrial scale is only one element in a comprehensive water filtration system. Carbon filters used to treat tap water primarily remove chlorine used in the water purification process. Carbon filters used to treat well water primarily remove organic material, including bacteria. Carbon filters used as part of an industrial water treatment regime are used as one layer in multi-layered filters.

    Maintenance

    • Carbon removes impurities from water by chemically bonding with the impurity. As available attachment sites become filled, carbon filters become less efficient. For this reason, it is important that they be replaced on a regular basis.

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