Methane emissions resulting from the release of methane trapped in coal beds can have a significant impact on the life cycle greenhouse gas (GHG) emissions associated with coal production. These emissions vary dramatically by coal rank, specific seam, and seam depth and thickness. This is particularly true of underground mines, where 50 of the nation’s 600 active underground mines are responsible for 98 % of all methane emissions. Various methods can be utilized to mitigate methane emissions, although at present these technologies have only seen limited deployment domestically due to lack of clear incentives or other barriers such as unclear ownership of rights to the gas, proximity of methane to market or a lack of desire to invest in new processes. Despite these factors, coal mine methane (CMM) recovery and use continues to grow, with over 46 billion cubic feet (Bcf) recovered domestically in 2006 – a 10 % increase from 2003. The U.S. Department of Environmental Protection (EPA) reports that of the 50 mines identified as potential candidates for CMM recovery (CMMR), 14 mines have implemented recovery strategies. It is expected that deployment will increase dramatically for gassy mines in the event that carbon regulation is passed, due to the potential cost associated with emissions: methane emissions would incur a cost 25 times higher than carbon emissions based on their increased global warming potential (GWP). This paper explores methane content and emissions associated with mining Illinois Basin coals such as Illinois No. 6. Illinois Basin bituminous coals tend to have a higher gas content than other bituminous coals, but the range of values is quite large, with methane contents as low as 10 standard cubic feet per ton of coal (scf CH4/ton) and as high as 250 scf CH4/ton being reported. As the methane content of the coal does not account for methane which has desorbed into the surrounding rock strata, specific methane emissions resulting from mining this coal will be even higher, with a 50 % increase in emissions expected
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