AWWA JAW49878

This study developed a way to rapidly and effectively evaluate the remaining life of a granular activated carbon (GAC) bed used to mitigate taste and odor episodes. The maximum attenuation of a 2-methylisoborneol (MIB) episode, a representative taste and odor compound, can rapidly be determined using laboratory-scale columns packed with partially spent GAC taken from full-scale operating adsorbers. These laboratory-scale columns closely simulated the performance of pilot-scale columns. The percent of a transient MIB load removed by GAC did not depend on the influent MIB concentration but did depend on the amount of natural organic matter adsorbed on the GAC surface. This approach can be used to determine GAC's potential percentage removal of taste- and odor-causing compounds as a function of GAC service time. It allows GAC to be tested to estimate its readiness for summer taste and odor episodes. Adsorption alone in GAC adsorbers that used < 10 min of empty bed contact time was insufficient to fully protect against typical MIB episodes. Includes 37 references, tables, figures.