Unlike sand filters, which remove mainly metals by their action, activated carbon filters are primarily used to remove chlorine (Cl), phenol (Ar-OH) and other organic compounds from treatment water, and are therefore also called dechlorinators. By removing these compounds, the treated water is characterized by a lack of unpleasant odor and taste, and acquires more desirable properties.

The activated carbon filtration process is important for industrial water treatment because raw water mainly contains large amounts of the above compounds and residual chlorine, and such a chemical composition is unfavorable for further processing within ion exchangers and reverse osmosis devices.