Biological Fluidized Bed Reactor Technology: The Optimal Approach for Treatment of Perchlorate Contaminated Groundwater or Drinking Water

The perchlorate anion has been detected in the drinking water of millions of people living in the U.S. often at concentrations above the level safe for human consumption. Ex-situ biotreatment has been utilized for perchlorate reduction at concentrations even below 100 ug/l. The principal objectives of this paper were to compare various bioreactor configurations in the treatment of low strength perchlorate contaminated aqueous streams, and to discuss the results of a demonstration project in which the fluidized bed reactor (FBR) configuration was applied for treatment of a source of drinking water contaminated with perchlorate and nitrate in the City of Rialto, CA. The granular activated carbon (GAC) or sand media based FBR and GAC, sand or plastic media based packed bed reactors (PBRs) have been the reactor configurations most widely applied for perchlorate treatment. Commercial scale cost information presented implies no significant economic advantage for the PBR relative to the FBR configuration. The results from the City of Rialto demonstration project confirmed the theoretical expectation that the GAC media based FBR technology was capable of reducing the perchlorate and nitrate to the concentration levels necessary to meet the State of California drinking water standards. The success of the demonstration project led to design of a full scale FBR system.