AWWA JAW56620

This study investigated removal of five haloacetic acids (HAA5) (monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid, and dibromoacetic acid) in biologically active carbon (BAC) columns. An acclimated granular activated carbon (GAC), or BAC, column effectively removed four of the HAA5 that had been spiked in the influent at 50 ug/L each. Only trichloroacetic acid, detected at 10 ug/L in the effluents, was not completely removed. After the biological activity on acclimated GAC was eliminated by autoclaving, the HAA removal efficiency was significantly reduced. In another experiment, the removal of HAAs in a new GAC column was continuously monitored for 76 days. The new GAC effectively removed HAAs. HAA removal at the beginning of this experiment was from carbon adsorption, whereas biodegradation was the HAA removal mechanism later in the experiment. The results of this study are significant to the water industry - removal of HAAs using BAC may provide a new technology for control of disinfection byproducts. Includes 22 references, figures.