Carbon Filter Media Tanks

Carbon Filter Media Tanks Carbon filters are used to remove organics (as TOC) and free chlorine from RO feed water. Bituminous carbon is used for industrial RO pretreatment applications. Organics are adsorbed on carbon particles for removal from water. Removal of chlorine involves an oxidation/reduction reaction with the carbon particles, where a transfer of electrons occurs from the activated carbon to the chlorine (the carbon acts as a reducing agent). Design fl ow rates should be 1 GPM/ft3 for TOC removal and 2 GPM/ft3 for chlorine removal when used for RO pretreatment. The expected TOC removal efficiency ranges from 25% to 80%, depending on the nature of the organics. Chlorine can be removed to less than 0.05 ppm. Activated carbon can also be used to remove chloramines in the same manner as chlorine, however, the contact time must be greater than for chlorine removal. For a 12 × 40 mesh carbon, contact times up to 30 min are required. Catalytic activated carbon can also be used to reduce the contact time for chloramine removal.