skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

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

Abstract

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.

Authors:
 [1];  [2];  [3];  [4];  [4];  [4];  [4];  [5];  [4];  [2];  [1]
  1. Miami University, Oxford, OH
  2. Stanford University
  3. Texas A&M University
  4. ORNL
  5. University of Oklahoma, Norman
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
986456
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Microbiology and Biotechnology; Journal Volume: 71; Journal Issue: 5
Country of Publication:
United States
Language:
English
Subject:
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

Citation Formats

Hwang, Chaichi, Wu, Wei-min, Gentry, Terry, Carroll, Sue L, Schadt, Christopher Warren, Watson, David B, Jardine, Philip M, Zhou, Jizhong, Hickey, Robert, Criddle, Craig, and Fields, Matthew Wayne. Changes in microbial community structure correlate with stressed operating conditions during start-up of a field-scale denitrifying fluidized bed reactor. United States: N. p., 2006. Web. doi:10.1007/s00253-005-0189-1.
Hwang, Chaichi, Wu, Wei-min, Gentry, Terry, Carroll, Sue L, Schadt, Christopher Warren, Watson, David B, Jardine, Philip M, Zhou, Jizhong, Hickey, Robert, Criddle, Craig, & Fields, Matthew Wayne. Changes in microbial community structure correlate with stressed operating conditions during start-up of a field-scale denitrifying fluidized bed reactor. United States. doi:10.1007/s00253-005-0189-1.
Hwang, Chaichi, Wu, Wei-min, Gentry, Terry, Carroll, Sue L, Schadt, Christopher Warren, Watson, David B, Jardine, Philip M, Zhou, Jizhong, Hickey, Robert, Criddle, Craig, and Fields, Matthew Wayne. Mon . "Changes in microbial community structure correlate with stressed operating conditions during start-up of a field-scale denitrifying fluidized bed reactor". United States. doi:10.1007/s00253-005-0189-1.
@article{osti_986456,
title = {Changes in microbial community structure correlate with stressed operating conditions during start-up of a field-scale denitrifying fluidized bed reactor},
author = {Hwang, Chaichi and Wu, Wei-min and Gentry, Terry and Carroll, Sue L and Schadt, Christopher Warren and Watson, David B and Jardine, Philip M and Zhou, Jizhong and Hickey, Robert and Criddle, Craig and Fields, Matthew Wayne},
abstractNote = {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.},
doi = {10.1007/s00253-005-0189-1},
journal = {Applied Microbiology and Biotechnology},
number = 5,
volume = 71,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2006},
month = {Mon May 01 00:00:00 EDT 2006}
}
  • 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, followedmore » 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.« less
  • High levels of nitrate are present in groundwater migratingfrom the former waste disposal ponds at the Y-12 National SecurityComplex in Oak Ridge, TN. A field-scale denitrifying fluidized bedreactor (FBR) was designed, constructed, and operated with ethanol as anelectron donor for the removal of nitrate. After inoculation, biofilmsdeveloped on the granular activated carbon particles. Changes in thebacterial community of the FBR were evaluated with clone libraries (n=500partial sequences) of the small-subunit rRNA gene for samples taken overa 4-month start-up period. Early phases of start-up operationwerecharacterized by a period of selection, followed by low diversity andpredominance by Azoarcus-like sequences. Possible explanations weremore » highpH and nutrient limitations. After amelioration of these conditions,diversification increased rapidly, with the appearance of Dechloromonas,Pseudomonas, and Hydrogenophaga sequences. Changes in NO3, SO4, and pHalso likely contributed to shifts in community composition. The detectionof sulfate-reducing-bacteria-like sequences closely related toDesulfovibrio and Desulfuromonas in the FBR have important implicationsfor downstream applications at the field site.« less
  • Biofiltration has been used for two decades to remove odors and various volatile organic and inorganic compounds in contaminated off-gas streams. Although biofiltration is widely practiced, there have been few studies of the bacteria responsible for the removal of air contaminants in biofilters. In this study, molecular techniques were used to identify bacteria in a laboratory-scale ammonia biofilter. Both 16S rRNA and ammonia monooxygenase (amoA) genes were used to characterize the heterotrophic and ammonia-oxidizing bacteria collected from the biofilter during a 102-day experiment. The overall diversity of the heterotrophic microbial population appeared to decrease by 38% at the end ofmore » the experiment. The community structure of the heterotrophic population also shifted from predominantly members of two subdivisions of the Proteobacteria (the beta and gamma subdivisions) to members of one subdivision (the gamma subdivision). An overall decrease in the diversity of ammonia monooxygenase genes was not observed. However, a shift from groups dominated by organisms containing Nitrosomonas-like and Nitrosospira-like amoA genes to groups dominated by organisms containing only Nitrosospira-like amoA genes was observed. In addition, a new amoA gene was discovered. This new gene is the first freshwater amoA gene that is closely affiliated with Nitrosococcus oceanus and the particulate methane monooxygenase gene from the methane oxidizers belonging to the gamma subdivision of the Proteobacteria.« less
  • Hot gas desulfurization with regenerable metal oxide sorbents is an essential part of the simplified integrated gasification combined cycle process which is currently being demonstrated at commercial scale. As part of a sulfur removal process development, Carbona Corporation is developing fluidized-bed reactor models for scale-up. In the first part of this work, the parameters for a uniform conversion model were determined to describe the conversion rate of ZnS regeneration with oxygen. A method using the uniform conversion model for fluidized-bed application is presented in this paper. The apparent activation energy for the global reaction rate constant obtained from pilot-scale fluidized-bedmore » tests is 200--210 kJ/mol. When using these reaction rate constants as inputs of a sensitivity analysis for a large-scale reactor model, in comparison with the rate constants reported earlier, some differences can be observed. The significance of the differences are discussed. It is stated that any zinc sulfate formed in fluidized-bed regeneration at temperatures 500--600 C will decompose, forming SO{sub 2}, at the actual regeneration temperatures of the bed (725--800 C) due to negligible O{sub 2} partial pressure.« less