Highlighted Research Projects
Comprehensive Investigation of Factors Enhancing Microbially Generated Coal Bed Methane
Vast reserves of coal in the United States represent a very large source of energy. However, coal mining is environmentally disruptive and hazardous to human health; moreover, coal-fired power plants emit combustion byproducts such as soot, mercury and sulfates that are of environmental concern. In addition, burning coal releases substantially more CO2, a global warming gas, to the atmosphere than natural gas relative to the amount of energy generated. If coal can be transformed to methane in situ via microbial activity, then a substantial clean burning energy reserve could be made available with a relatively minor environmental impact.
Research has shown that microorganisms are capable of converting coal to methane, though at widely different rates under controlled laboratory conditions. Indeed, much of currently produced coalbed methane (CBM) is of biological origin (e.g., Powder River Basin, Wy.).
The methane is produced by methanogenesis, a process in which microorganisms (methanogens) convert substrates such as acetate or CO2 and hydrogen into methane. However, the methanogens are unable to directly utilize coal as a substrate. Before methanogenesis, a consortium of “hydrolytic” microorganisms convert the coal into soluble organic molecules, after which another group of microorganisms called “fermenters” convert the soluble organic matter into low molecular weight molecules such as acetate that can be utilized by the methanogens. Beyond this broad generalization, the processes leading to methanogenesis in coal are not well understood.
Simplified schematic illustrating the methanogenic degradation of organic matter. Circled numbers indicate the metabolic group of microbes involved in the particular stage of degradation. 1: initial hydrolysis of polymeric carbon; 2: fermentation of monomers to low molecular weight compounds; 3: aceticlastic methanogenesis and 4: CO2-reducing methanogenesis from fermentation intermediates.
This on-going research project is a systematic investigation of different components of biogenic methane production to better understand how the process could be enhanced and accelerated. Specifically, we are examining the efficacy of adding nutrients needed by the organisms to the coal and chemical pre-treatment of the coal to release soluble organic matter to feed methanogenesis. Additionally, we will characterize and monitor the microbial populations and their response to these manipulations using DNA cloning and sequencing, quantitative polymerase chain reaction (qPCR), phospholipid fatty acid (PLFA) and phosphoether lipid (PEL) analysis. We also seek to characterize the biochemical pathways involved in the conversion of coal to methane to gain an understanding of the relevant processes, the rate limiting steps and the interactions within microbial communities. Specific metabolites involved in the conversion of coal to methane will be identified using gas chromatography-mass spectrometry (GC-MS) and/or liquid chromatography- electrospray ionization-mass spectrometry (LC-EIS-MS). An improved understanding of the overall process will allow us to optimally stimulate the conversion of coal to methane.
Objectives
- Identify chemical constituents of coal that are bioconverted
- Identify organisms associated with biogas generation from coal
- Characterize the influence of culture growth amendments and conditions on biogas generation
- Determine impacts of coal pre-treatment on levels of biogas precursor compounds, microbial communities, and ultimate methane generation
- Determine the rate limiting step(s) of microbial methane generation from coal
- Capture chemical and microbial dynamics observed in a computer model, to allow comparisons of different incubation scenarios
The Team
A multi-disciplinary and multi-institutional team has been assembled to pursue this research.
Colorado School of Mines (CSM)Dr. Junko Munakata-Marr, Lead PI & microbial community structure by DNA analysis (http://ese.mines.edu/people/faculty/munakata.html)
Lisa Gallagher, Ph.D. candidate; microbial community structure by DNA analysis
Dr. Kevin Mandernack, PI; microbial community structure by phospholipid analysis (http://chemistry.mines.edu/faculty_bio_mandernack.shtml)
Andy Glossner, Ph.D. candidate; microbial community structure by phospholipid analysis
Dr. Linda Figuroa, PI; Modeling (http://ese.mines.edu/people/faculty/figueroa.html)
Dr. Lee Landkamer, PI; Project Management
United States Geological Survey (USGS)
Dr. Steve Harris, PI; Characterization of biodegradable components of coal and nutrient optimization
University of Wyoming (UW)
Dr. David Bagley, PI; optimization and characterization of microbial processes (http://wwweng.uwyo.edu/civil/faculty/bagley.html)
Yiping Lui, Ph.D. candidate; optimization and characterization of microbial processes
Dr. Michael Urynowicz, PI; coal pre-treatment (http://wwweng.uwyo.edu/civil/faculty/urynowicz.html)
Zaixing Huang, Ph.D. candidate; coal pre-treatment
Dr. Franco Basile, PI; characterization of soluble coal components and metabolites (http://uwacadweb.uwyo.edu/BASILERESEARCHMS/FBasile%20CV.htm)
Wesley Rodgers, Ph.D. candidate; characterization of soluble coal components and metabolites
Contact Information
Lee Landkamer: llandkam@mines.edu
Junko Munakata-Marr: 303-273-3421 or junko@mines.edu
