Enhanced coal-bed methane

To estimate the large-scale storage capacity of 45 important coal basins during Enhanced Coal Bed Methane Recovery (ECBM) in China, Li et al. used an equation which can be modified to a simpler form without considering the different coal bed basins [63, 79]. 

PhungQ.H., Kyuro S., et al. Numerical simulation of C02 enhanced coal bed methane recovery for a Vietnamese coal seam. 2010 Journal of Novel Carbon Resource Science 2 1-7. 

Displacing the methane tied up in deep unmineable coal adds another small carbon sink to the portfolio of options and this process is called enhanced coal bed methane recovery. When injected into a coal bed, C02 can replace adsorbed methane. By doing so, coal beds can serve as a C02 reservoir and a source for methane production (Parson and Keith, 1998). This method is attractive in the sense that most of the injected C02 will be immobilized by either physical or chemical adsorption on the coal surface. 

Storage in coal seams Storage in salt caverns Storage in abandoned mines Enhanced coal-bed methane production Storage in unminable coal seams... 

ECBM EGR EIA EOR EPR Enhanced coal-bed methane Enhanced gas recovery Energy Information Administration (US DOE) Enhanced oil recovery European Pressurised Water Reactor Evolutionary Power Reactor... 

Carbon Sequestration Study on the potential of COj storage in the "Kempen "-Flanders a study on the influence of super critical COj on reservoir rocks and participation to the European project RECOPOLforthe enhanced coal bed methane extraction. 

Figure 3.4 Options for the geological storage of carbon dioxide. 1. Deep unused saline formations (aquifers). 2. Use of carbon dioxide for enhanced oil recovery. 3. Depleted oil and gas reservoirs. 4. Deep unmineable coal seams. 5. Use of carbon dioxide in enhanced coal-bed methane recovery. 6. Other suggested options (e.g., salt caverns, basalts, oil/gas shales, disused mines)." (Courtesy of Intergovernmental Panel on Climate Change).

Injecting carbon dioxide into deep, unmineable coal seams where it is adsorbed to displace methane (effectively natural gas) is another potential use or disposal strategy. Currently, the economics of enhanced coal bed methane extraction are not as favorable as enhanced oil recovery, but the potential is large. 

Gale, J. Freund, P. 2001. Coal-bed methane enhancement with C02 sequestration worldwide potential, Environmental Geosciences, 8, 210—217. 

Other potential uses For example, applications as a solvent in separations and reactions, expanding markets for chemicals from carbon dioxide, enhanced recovery of oil, natural gas, and coal bed methane. 

The greater the amount of carbon dioxide injected, the more will return to the surface with the methane. This creates the need for a gas-separation plant of the type shown in Figure 3.2. The removal of carbon dioxide from oil is much simpler than from methane, which is why enhanced oil recovery is practised more widely than enhanced gas recovery. With an extensive coal seam, it will be necessary to drill injection and extraction wells every few hundred metres or so. These, together with the associated gas compressors, distribution pipes and pumps, access roads, etc., will turn a rural landscape into an industrial site. When the operational/safety issues and the extent of industrialization become fully appreciated, not to mention the impact on the ecological habitat, there may well be local opposition to the recovery of coal-bed methane - with or without carbon dioxide injection and storage. 

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