Demonstration of a Full-Scale Fluidized Bed Bioreactor for the Treatment of Perchlorate at Low Concentrations in Groundwater
ER-200543
Objective
Biological treatment of perchlorate
The objective of this project is to demonstrate the efficacy of a fluidized bed bioreactor (FBR) system for the treatment of low concentrations of perchlorate in groundwater. Biological treatment is considered one of the most promising technologies for the remediation of perchlorate-contaminated water. For this demonstration, a critical issue in applying such a biological treatment technology is qualifying the system's robustness in operating effectively under various loading conditions. The project will focus on how low perchlorate concentrations, self-seeding of the reactor, and short-term interruptions in system operation affect performance. Such effects have not been evaluated with any of the other FBR systems currently in operation. This study also will evaluate operation of the FBR treatment system in conjunction with additional downstream equipment that will result in production of potable water. Such a remediation system will provide a low-cost alternative for the treatment of perchlorate-contaminated drinking water aquifers.
Technology Description
Theoretical biological treatment process within the FBR.
A fluidized bed bioreactor is a fixed-film reactor in which the biological media is suspended or fluidized within the reactor vessel by the upward flow of water through the system. Typically, sand or granular activated carbon is used in these systems for microbial growth attachment. Because the media particles are small and suspended, they present a large surface area for microbial growth and promote a biomass density that is often several times that of other bioreactor designs under similar loading conditions. An electron donor (i.e., acetic acid) is provided to the FBR where, under anoxic conditions, it is used in the denitrification/perchlorate-reduction process. The byproducts of the process are nitrogen gas, chloride ions, carbon dioxide, heat generation, and additional biomass. The effluent water from the FBR then passes through an aerator, multimedia filter, and liquid granular activated carbon, resulting in the production of potable water.
Benefits
Typically, for drinking water applications, existing perchlorate removal technologies utilize the principle of simple phase transfer of the contaminant from the water to the solid phase. This requires additional treatment of perchlorate in the solid phase. In contrast, the FBR technology completely destroys the nitrate and perchlorate in the influent water. The complete destruction of the nitrate and perchlorate ions ensures that they will no longer be environmental hazards for future generations. In addition, costs for the FBR treatment train have been shown to be up to 60% less expensive than current state-of-the-art treatment technologies. It is expected that this demonstration will corroborate such findings regarding the economic benefits of this technology to the Department of Defense. (Anticipated Project Completion - 2013)
Project Documents
Points of Contact
Principal Investigator
Dr. Todd Webster
Envirogen Technologies Inc.
Phone: 619-887-2587 (Phone/Fax) x(619) 887-1385 (Cell)
Fax: 619-887-2587 (Phone/Fax)
Project Documents
Document Types
- Fact Sheet - Brief project summary with links to related documents and points of contact.
- Final Report - Comprehensive report for every completed SERDP and ESTCP project that contains all technical results.
- Cost & Performance Report - Overview of ESTCP demonstration activities, results, and conclusions, standardized to facilitate implementation decisions.
- Technical Report - Additional interim reports, laboratory reports, demonstration reports, and technology survey reports.
- Guidance - Instructional information on technical topics such as protocols and user’s guides.
- Workshop Report - Summary of workshop discussion and findings.
- Multimedia - On demand videos, animations, and webcasts highlighting featured initiatives or technologies.
- Model/Software - Computer programs and applications available for download.
- Database - Digitally organized collection of data available to search and access.