It is estimated that only 5% of Alberta’s CBM reserves are recoverable (Rieb, 2006). A variety of techniques such as horizontal drilling and new fracturing methods have allowed greater recoveries of the methane gas. Alberta Innovates – Technology Futures (formerly the Alberta Research Council) is developing a biotechnology that stimulates and enhances biogenic methane production coal seams. Biogenic methane production is believed to have occurred in the geological past, and is believed to be still occurring in deep, subsurface coal seams albeit at extremely slow rates. It is postulated that the native microorganisms are nutrient limited and, based on laboratory evidence, by adding an organic, nitrogen-rich nutrient, the methane production rate can be increased up to 30-fold over non-amended cutlures. The microbial diversity of Alberta coal seams has begun to be mapped out using state-of-the-art genomic sequencing techniques. It appears the geophysical environment has a strong influence on the types of microbes present as the microbial populations from deeper, more saline Mannville coals are significantly different than the microbes detected in Horseshoe Canyon coals. The microbial population changes upon addition of a nutrient, with shifts occurring in the types of fermenting organisms and methanogenic species. Low molecular weight monocarboxylic acids were observed to be produced and then consumed over the incubation period. These methanogenic precursor substrates accumulated in cultures with only nutrient and no coal. Much lower methane production occurred in these cultures suggesting an unbalanced nutritional state, whereas those cultures with un-limiting carbon from coal and nitrogen source from the nutrient generated large amounts of methane. The effects of surface area, bioavailability of coal moieties and coal porosity and permeability on biogenic methane production are under investigation. Results will aid in the design and deployment of an effective enhanced biogenic methane coal bed field trial.

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