Field evaluation of a granular activated carbon fluid‐bed bioreactor for treatment of chlorobenzene in groundwater

摘要

AbstractAlthough granular activated carbon (GAC), fluidizedbed bioreactors have been used for treatment of groundwater containing readily biodegradable organic compounds, there is only limited experience with treatment of chlorinated organics found at many industrial sites. This paper describes a field evaluation of a GAC fluid‐bed bioreactor operated at various chlorobenzene concentrations and organic loading rates over a 7‐ month period. Microorganisms used to seed the bioreactor were provided by activated sludge from the site, as well as indigenous chlorobenzene‐degrading bacteria present in the groundwater. Removal efficiencies exceeding 99.99% were achieved at organic loading rates between 6 and 10 pounds of total oxygen demand (lb TOD) per 25 cubic feet per day. Influent chlorobenzene concentrations ranging from 100 to 170 ppm were consistently reduced to below the detection limit of 10 ppb. Economic evaluation indicates that groundwater treatment costs for the bioreactor were lower than other conventional technol