Changes in microbial community structure correlate with stressed operating conditions during start-up of a field-scale denitrifying fluidized bed reactor

Journal Article · Mon May 01 00:00:00 EDT 2006 · Applied Microbiology and Biotechnology

DOI:https://doi.org/10.1007/s00253-005-0189-1· OSTI ID:986456

Hwang, Chaichi ^[1]; Wu, Wei-min ^[2]; Gentry, Terry ^[3]; Carroll, Sue L ^[4]; Schadt, Christopher Warren ^[4]; Watson, David B ^[4]; Jardine, Philip M ^[4]; Zhou, Jizhong ^[5]; Hickey, Robert ^[4]; Criddle, Craig ^[2]; Fields, Matthew Wayne ^[1]

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1. Miami University, Oxford, OH
2. Stanford University
3. Texas A&M University
4. ORNL
5. University of Oklahoma, Norman

High levels of nitrate are present in groundwater migrating from the former waste disposal ponds at the Y-12 National Security Complex in Oak Ridge, TN. A field-scale denitrifying fluidized bed reactor (FBR) was designed, constructed, and operated with ethanol as an electron donor for the removal of nitrate. After inoculation, biofilms developed on the granular activated carbon particles. Changes in the bacterial community of the FBR were evaluated with clone libraries (n=500 partial sequences) of the small-subunit rRNA gene for samples taken over a 4-month start-up period. Early phases of start-up operation were characterized by a period of selection, followed by low diversity and predominance by Azoarcus-like sequences. Possible explanations were high pH and nutrient limitations. After amelioration of these conditions, diversification increased rapidly, with the appearance of Dechloromonas, Pseudomonas, and Hydrogenophaga sequences. Changes in NO{sub 3}, SO{sub 4}, and pH also likely contributed to shifts in community composition. The detection of sulfate-reducing-bacteria-like sequences closely related to Desulfovibrio and Desulfuromonas in the FBR have important implications for downstream applications at the field site.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 986456
• Journal Information: Applied Microbiology and Biotechnology, Vol. 71, Issue 5; ISSN 0175-7598
• Country of Publication: United States
• Language: English

Related Subjects

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEFENSE
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE
ACTIVATED CARBON
BINDING ENERGY
DESULFOVIBRIO
DETECTION
DIVERSIFICATION
ELECTRONS
ETHANOL
FLUIDIZED BED REACTORS
GENES
INOCULATION
NATIONAL SECURITY
NITRATES
NUTRIENTS
PONDS
PSEUDOMONAS
REMOVAL
START-UP
VALENCE
WASTE DISPOSAL