Deep Coal Energy Jack Hamilton, Ph.D. Jack Adams, Ph.D. John McLennan, Ph.D. Mike Free, Ph.D. Mike Nelson, Ph.D.
Dec 19, 2015
Deep Coal Energy
Jack Hamilton, Ph.D.Jack Adams, Ph.D. John McLennan, Ph.D. Mike Free, Ph.D. Mike Nelson, Ph.D.
The objective of this research is to achieve a methodology that can recover energy from carbon resources that are otherwise unrecoverable using conventional techniques, primarily by using microbe consortia to produce methane – the cleanest variety of fossil fuel.
The first target for evaluation is existing coal-bed methane production that is in decline, because of accessibility and the existing infrastructure.
Ultimately, a carbon-neutral power generation scenario may be feasible.
From: U.S. EnergyInformation Agency2005
In billion short tons
In Billion Short Tons
Energy / Emissions
Fuel TypeApproximate Energy (KBTU/Kg)
Approximate CO2 Emissions (Kg/MBTU)
Wood (50% C) 14 88Coal (poor) (50 -80% C) 14 102Coal (premium)(86 - 96% C - C135H96O9NS) 26 92Ethanol (C2H5OH) 28* 51*Petroleum(C5H12 to C36H74)
43 71 gasoline73 diesel
Methane (CH4) 51 52Hydrogen 133 None(*) It takes ~44 KBTU of energy to produce a kilogram of EtOH from corn!
Coal Bed Methane
Methane occurs in most coals, but water permeates coal beds, and its pressure traps methane within the coal. To produce methane from coal beds, water must be drawn off first, lowering the pressure so methane can flow out of the coal and to the well bore.
The coal acts as both the source of the gas and the storage reservoir
CO2 is preferentially adsorbed on fracturesurfaces and displacesmethane from those surfaces
Coal Bed Methane
CBM existing today was formed millions of years ago in an environment that does not exist in the CBM deposits today
If only 1/100th of 1% of US coal reserves were converted into methane by microbes, and captured above ground, gas resources would increase by 23 Tcf, or approximately 16% of current US reserves (Scott, 1994)
An infrastructure of ~30,000 CBM wells currently exist to take advantage of this technology – some of these wells are nearing methane depletion
THE GOAL To initiate or enhance methane production by introducing a mixture of
nutrients, non-pathogenic bacteria and Archaea that work together to break down the organic carbon structure in coal and produce methane
Microbes
Microorganisms are the earliest forms of life on earth; occupy almost every conceivable ecological niche -- even the harshest, most extreme, and toxic environments -- about 1 billion live in a single teaspoon of moist soil
Methanogens
Strict anaerobes
They produce large quantities of methane as a byproduct of their metabolism
They are members of the domain Archaea
Form mutualistic relationships with other microbes allows them to exist in a wide variety of environments
Structure of Coal
Coal is a mixture of compounds, its chemical formula is approximated by C135H96O9NS. This means that by mass, carbon accounts for almost 85% of coal.
GEOPOLYMERS IN COAL,OIL SHALE, TAR SANDS,
AND HEAVY OILS VARIOUS HUMIC ACIDS & OTHERCOLLOIDAL POLYMERS
Microbial Methane Production
FATTY ACIDS, SUGARS, AMINO ACIDS,
HydrolyticFermentativeBacteria
HydrolyticFermentativeBacteria
Syntrophic FermentativeAcetogenicBacteria CH4 + HCO3
-MethanogenicBacteria
CH4 + 2H2O
SEQUESTRATION OF CO2
NH3, H2S, CO2, H+, ACETATE +
MethanogenicBacteriaH+
Methanogenesis
Methane production depends on: Site environment, microbes present, and nutrient components available
MICROBES
METHANE
SUBSTRATES
Microbes & Nutrient Components
Correct ratios of C:N:P:S:Other minerals:Vitamins
Proper nutrient component composition
Optimized non-pathogenic microbial populations
Site chemistry adjustments
(CF
/TO
N)
Overall Objective
Commercialize microbial enhanced coal bed methane production by increasing the understanding of the process, optimizing production, facilitating both above ground and in-situ application, and partnering with industry for large-scale implementations
Goals
Perform small (~1/2 ton) pilot-scale testing with different coal types to optimize microbes and nutrients-environment ▪ Understand factors affecting enhanced microbial CBM production ▪ Examine CO2 addition
Establish a partnership with industry to conduct a commercial-scale pilot test of the enhanced microbial CBM technology ▪ Conduct on-site methane production testing to optimize process
Initiate a full-scale model production facility and market the proven technology within two years
Goals
Test established delivery methods - hydraulic fracturing and/or remote mining to achieve adequate reactive surface area
Examine potential environmental risks
Acquire data to assess potential for carbon-neutral power generation
Initiate a full-scale in situ model production facility and market the technology
Examine the potential for integrating on-site power generation
Why this Approach will be Successful?
The multidisciplinary team understands the complexities of this project based on prior success at a large scale in other related in-situ and industrial microbial systems
This approach addresses the important challenges that are likely to facilitate a transition from small-scale testing to large-scale commercialization
Demonstrated successful approach at bench scale and are ready to move to small-scale pilot tests
Success demonstrated in other full-scale bioreactor and in situ microbial transformations
CH4 RECOVERYGEOPOLYMERS IN
COAL, OIL SHALE, OIL SANDS, AND HEAVY
OILS
HydrolyticFermentativeBacteria/Archaea
H2O - FATTY ACIDS,SUGARS, AMINO ACIDS,
NH3, H2S, CO2, ACETATE, H+MethanogenicBacteria/Archaea
Fracture Solution / Microbe /Nutrient / CO2 re-injection
Conversion of Injected CO2 to Methane
CO2
CH4
Storage
BiogenicMethane
REDUCED CARBON EMISSION COAL ENERGY