Coalbed methane

G. S. Penny and M. W. Conway. Coordinated studies in support of hydraulic fracturing of coalbed methane final report (July 1990-May 1995). Gas Res Inst Rep GRI-95/0283, Gas Res Inst, September 1995. 

C02 in gaseous form is injected into the coalbed, 300 to 600 metre depth, and adsorbed on the matrix pores, releasing the existing CH4 in the same (two molecules of C02 adsorbed by each CH4 molecule that travels). This has led to the possibility of storing C02 in coal seams, while CH4 recovered is valued. This technique is called enhanced coalbed methane production (ECBM). 

OzgenKaracan C. and Okandan E. Assessment of energetic heterogenitiesof coals for gas adsorption and its effect on mixture predictions for coalbed methane studies. 2000 Fuel 79(15) 1963-1974. 

PagnierH.J.M., et al. C02-sequestration in the Netherlands inventory of the potential for the combination of subsurface carbon dioxide disposal with enhanced coalbed methane production. In Proceedings of Fifth International Conference on Greenhouse Gas Control Technologies, CSIRO Publishing, Collingwood, Australia. 2001 555-560. 

Comparison of C02-N2-enhanced coalbed methane recovery and CO2 storage for low- high-rank coals, Alberta, Canada and Shanxi, China... 

Mavor, M.J., Gunter, W.D., Robinson, J.R. 2004. Alberta multi-well micro-pilot testing for CBM properties, enhanced coalbed methane recovery and C02 storage potential. Paper SPE 90256, presented at SPE Annual Technical Conference and Exhibition, Houston, Texas. 

Wong, S., Law, D., Deng, X., Robinson, J. et al. 2007. Enhanced coalbed methane and C02 storage in anthracitic coals Micro-pilot test at South Qinshui, Shanxi, China. International Journal of Greenhouse Gas Control, 1, No. 2, 215-222. 

Development of Advanced Reservoir Characterisation and Simulation Tools for Improved Coalbed Methane Recovery. Led by Imperial College of Science Technology and Medicine, the main objective of this project is to develop technology and tools to more accurately assess the potential for improved methane recovery and COj sequestration by investigating the basic scientific phenomena of COj coal injection and retention. The researchers primary objective is to achieve a more comprehensive understanding of the fundamental mechanisms of water and CO2-CH4 adsorption/desorption, diffusion/counter diffusion, and 2-phase flow under simulated reservoir conditions (stress, pore pressure, and temperature). The results of these studies will then be applied to design of a CO2-ICBM recovery and COj sequestration simulator for the European industry. 

Enhanced Coalbed Methane Production and Sequestration ofC02 in Unmineable Coal Seams. This project aims to demonstrate the use of "slant-hole" drilling to degasify unmineable coal seams. Upon drainage of 50-60% of the CBM, CO2 will be injected into some of the slant-hole wells to enhance CBM production. 

Clarke, L. B. 1996. Environmental aspects of coalbed methane production, with emphasis on water treatment and disposal. Transactions of the Institution of Mining and Metallurgy, (Section A), 105, A105-A113. 

McBeth, I., Reddy, K.J. and Skinner, Q.D. (2003) Chemistry of trace elements in coalbed methane product water. Water Research, 37(4), 884-90. 

Coalbed Methane (CBM) A natural methane gas that is found in coal seams, while traditional natural gas deposits are trapped in porous rock formations. A small amount of CBM is already produced successfully in the Rocky Mountain region of the U.S. 

Methane A colorless, odorless, flammable hydrocarbon gas (CH4) the major component of natural gas. It is also an important source of hydrogen in various industrial processes. Also, see Coalbed Methane (CBN). ... 

Natural Gas Exploration Production Coalbed Methane Development Power Generation Gathering Pipelines... 

Pyrak-Nolte, L.J. and Haley, G.M. (1993) Effective cleat porosity and cleat geometry from Wood s metal Porosimetry. Proceedings of the 1993 International Coalbed Methane Symposium, University of Alabama/Tuscaloosa, May 17-21, 639-647... 

INCLUDING C02 SEQUESTRATION AND COALBED METHANE RECOVERY ECONOMICS, C02 EMISSIONS, AND ENERGY BALANCE... 

Wyodak coal from Wyoming was selected as a suitable low-rank Western coal for this study. It is inexpensive to produce and is available in an abundant supply. Additionally, the regulations in Wyoming permit the extraction of coalbed methane, making it attractive for C02 sequestration and coalbed methane recovery. Coal would be mined from this region gasified to produce hydrogen then the C02-rich off gas would be injected into unmineable coal beds. 

In order to compare the economics as well as the overall C02 emissions from each schematic studied in this joint venture, a reference case was analyzed. The reference case included only the process steps associated with coal gasification, shift, and hydrogen purification, but none of the steps associated with C02 sequestration or coalbed methane recovery. Three other process schemes were examined in this study and compared to the reference case. Figure 1 depicts simplified process flow diagrams for the reference case and the other three schemes (note the overall heat integration for each scheme is not shown). The top portion of the figure shows the process steps that are the same for each scheme up to hydrogen purification, while the operations inside the dashed boxes represent the steps that differ between the four cases. 

Case Coal rate (as received) (kg/hr) Coalbed methane (kg/hr) h2 production (kg/hr) Electricity requirement (MW) Energy ratio... 

To adequately determine the overall effect of C02 for each option studied, the C02 balance must incorporate C02 emissions in addition to those emitted from the process itself. For example, each case produces electricity, except for the maximum hydrogen production case (Case 3), and for these cases (Cases 1, 2, and 4) a C02 emissions credit must be taken for displacing electricity from the grid. Because the maximum hydrogen production case (Case 3) requires some grid electricity, the system must be debited (rather than credited) with C02 emissions equivalent to the plant s net electricity requirement. Additionally, for the two options that recover coalbed methane (Case 3 and 4), each of those systems must be credited... 

North American Coalbed Methane Resource Map, gti e p Services, Des Plaines, IL 60018. 

Gurba L. W. and Weber C. R. (2001) Effects of igneous intrusions on coalbed methane potential, Gunnedah Basin, Australia. Int. J. Coal Geol. 46, 113—131. 

ICF Resources (1990) The United States coalbed methane resource. Quart. Rev. Methane Coal Seams Technol. 7, 10-28. 

Kuuskraa V. A., Kelafant J., and Kuuskraa J. A. (1997) A critical look at the geologic and reservoir controls on producing Appalachian Basin coalbed methane. AAPG Eastern Section and the Society for Organic Petrology Joint Meeting. Abstracts, AAPG Bulletin. 81, 1556. 

Levine J. R. (1987) Influence of coal composition on the generation and retention of coalbed natural gas. Proceed. 1987 Coalbed Methane Symp. 15—18. 

Levine J. R. (1991) The impact of oil formed during coalification on generation and storage of natural gas in coalbed reservoir systems. Proc. 1991 Coalbed Methane Symp. 307-315. 

Pashin, J. C., 1994, Coal-body geometry and synsedimentary detachment folding in Oak Grove coalbed methane field. Black Warrior Basin, Alabama AAPG Bulletin, v. 78, no. 

Stratigraphy and structure of coalbed methane reservoirs in the United States An overview International Journal of Coal Geology, v. 35, p. 1-4. 

Pashin, J. C., Carrol, R. E., Hatch, J. R., and Goldhaber, M. B., 1999, Mechanical and thermal control of dealing and shearing in coal Examples from the Alabama coalbed methane fields, USA in Mastalerz, M., Glikson, M., and Golding, S. D., eds.. Coalbed Methane Scientific, Environmental, and Economic Evaluation Dordrecht, Kluwer Academic Publishers, p. 305-328. 

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