Activated CarbonWhat is it? Activated carbon filters can be made up of coconut husks, peanut shells, coal, or other materials. Think of an activated carbon filter as a sponge on steroids; it filters out particles too large to fit through the gaps, and it attracts organic contaminants that are responsible for taste, odor, and color problems and binds them through adsorption to the block of carbon.
Adsorption? Adsorption is an increase in accumulation of contaminant on a surface, and activated carbon has an incredible amount of surface area. During the manufacturing process, millions of pores are created on the surface of activated carbon, creating a surface area of over 60 football fields in every pound of AC! That entire surface is constantly attracting and binding harmful chemicals, removing them from the water stream.
Where does activated carbon fit in? Activated carbon (AC) filtering is an important step in the water purification process. After water has passed through a physical screening device, it flows through either granules (GAC) or a solid block (SBAC) of activated carbon.
What’s the difference between GAC and SBAC? Granules (GAC) are cheaper, but can harbor more places for bacteria. Solid blocks are more expensive, and provide more surface area combined with a longer contact time than granules. Because blocks tend to have a finer filter, they can clog up more easily.
Why does Exup use it? Activated carbon is an excellent water purifier that works well, relatively cheaply, and without any special electrical power needs. It is easy to maintain and fairly durable. Large activated carbon filters can last 2 or 3 years before they need to be replaced.
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