Fossil Fuel Bioprocessing projects
Distribution & Diversity of Metabolic Processes in Subsurface Microbial Communities Integrated with Reservoir Environmental Conditions and Geological History: A Universal Template for MEHR
It may be possible to increase the amount of oil that can be extracted from subsurface oil field reservoirs using microbial metabolisms. This project is determining the distribution, frequency, and expression of genes in subsurface microbial communities in order to infer the unique metabolic processes inherent to this environment. Findings will be integrated with reservoir environmental conditions and geological history to establish a universal template for developing Microbially Enhanced Hydrocarbon Recovery (MEHR) strategies in oil and gas reservoirs, oil shales, tar sands, and coal beds under a range of subsurface temperature and pressure conditions.
A first-generation GeoBioCell microfluidic device was designed, constructed and applied to MEHR experimentation. Direct observation and spectroscopic analyses were conducted of fluids (water, hydrocarbons, gases), minerals (calcite, aragonite, silicates), and microbes (microbes in pore water or biofilms). The first round of GeoBioCell experimentation focused on determining the role of bacteria in rock pore space CaCO3 precipitation. Initial experiments utilized cultures of the bacterium Psuedomonas stutzeri that were injected into the two inlet ports of the GeoBioCell with solutions of 1.5 mM acetate and 1 mM NO3. Once a healthy biofilm was established and sustained along a central mixing line, 10 mM CaCl2 was added in both inlet solutions to drive CaCO3 precipitation. Multiphoton confocal microscopy and Raman confocal imaging microscopy were used to analyze the biofilm growth and carbonate crystal precipitation. Inoculation with three different types of microbial cell samples (live active, live inactive and dead) resulted in enhanced growth of CaCO3 mineral precipitation. This suggests that cell membrane-bound biomolecules and extra polymeric substances (EPS) concentrations in the microbial mat biomass may explain the observed increase in CaCO3 precipitation rate with increasing biomass.
In addition, fresh cryogenically drilled BP cores from the Athabasca River region of northern Alberta, Canada, were sampled in March 2012. Cryogenic drilling (conducted at approximately -20 to -30oC) substitutes liquid nitrogen-cooled air and gas for drilling muds, thus dramatically reducing contamination during drilling. This simultaneously preserves indigenous subsurface microbes inhabiting the reservoir for both enrichment culturing and molecular analyses. A pilot set of three 10 cm-long bitumen and heavy oil impregnated frozen half cores from the Devonian Grosmont Carbonate were collected, which are stored in -80oC anaerobic freezers at Illinois and are ready for analysis. In addition, 15 cryogenic core samples from the overlying bitumen-saturated Cretaceous Ft. McMurray sandstone were similarly sampled and are stored at Illinois. Multiple microbial cultures have been successfully extracted and cultivated from these samples and will be used in future GeoBioCell experimentation.
Fouke’s lab completed field analyses and sample collection at two strategic sites, the Athabascan Tar Sands of northern Alberta, Canada and the Milne Point fields in Prudhoe Bay, Alaska. They initiated design and construction of a high-throughput micromodel experimental test bed, called the GeoBioCell (GBC). The GBC will be used to quantitatively determine how candidate microbes can be used to degrade oil and control host rock porosity and permeability.
Environmental metagenomics coupled with newly developed subsurface sampling probes have provided a first glimpse of the resident native microbes inhabiting deeply buried saline sandstone reservoirs that are important for carbon sequestration, gas storage and hydrocarbon exploration. A low-diversity indigenous microbial community, dominated by the proteobacterium Halomonas sulfidaeris, inhabits warm saline formation waters at a burial depth of ~1.8 km within Cambrian-age Mt. Simon Sandstone, a regionally distributed, highly porous and permeable reservoir in the midcontinent Illinois Basin. It appears that H. sulfidaeris-dominated communities are capable of iron, methane, nitrogen and aromatic hydrocarbon metabolisms.
Published in 2012
Detection and Preliminary Characterization of Active Iron-Reducing Bacterial Populations in Deeply Buried (1.7-2.0 KM) Saline Sandstone Reservoirs of the Illinois Basin, Y. Dong, R. Sanford, I. Cann, R. Mackie, R. Locke, B. W. Fouke, Midcontinent USA, American Society of Microbiology, 2012 General Meeting, San Francisco, CA.