Activated Carbons as Adsorbents of Bacteria

The establishment of bacteria in carbon beds during the water treatment can have both beneficial and harmful effects. Thus, as a beneficial effect, it has been proposed that in the biological activated carbon (BAC) process, carbon bed life can be prolonged by converting a portion of the recalcitrant organics to biodegradable organics by preozonation. The microorganisms attached to the GAC then convert the biodegradable portion to biomass, carbon dioxide, and waste products before that material can occupy adsorption sites on the GAC. The harmful effect of the bacterial colonization of GAC in the beds is the increase of the number of bacteria entering the distribution system. Thus, some investigators have reported the release of substantial numbers of coliforms in water treated with GAC.