Developments in Natural Gas Supply and Transportation: Coal Bed Methane E.J. Anthony CanmetEnergy, NRCan, Ottawa, June 2009
Future Energy Supplies Currently uncertainty about future energy prices Price spikes are expected Also, uncertainty about reliable energy supplies Predictions abound about potential long-term availability of oil, gas and coal Nuclear is unlikely to substitute for fossil fuels, even if public resistance to building new plants can be overcome Time scale and capital cost for significant nuclear plant construction remain problematic
Coal has Issues Georgia State Court blocks a $2 billion coal-fired power plant on the basis of CO 2 emissions, citing an April 2007 Supreme Court finding that EPA has the authority to regulate GHGs Environmental activists say the Georgia ruling should influence all future permits for coal plants: Thanks to this decision, coal plants across the country will be forced to live up to their clean-coal rhetoric Bruce Niles, Sierra Club
Canada continues to use natural gas faster than it replenishes its reserves Demand expected to increase due to need in oil sands upgrading New sources are needed! Future of Natural Gas
The Case for Methane Methane is the best fuel for power generation New sources of gaseous fuel or methane are strongly needed Alternatives are being explored Three important contenders are underground gasification gas hydrates, and coal bed methane
Coal Bed Methane Coal bed methane is being explored worldwide, notably in the US, Canada, Australia and China Canada's CBM now contributes > 20 Mm 3 per day to national production, and is forecast to increase to 85 Mm 3 per day by 2024. CBM resources currently amount to about 19.8 trillion m 3, with 5 to 20% recoverable using conventional technology Comparisons CBM accounts for ~7% of total natural gas production in the United States Established conventional gas reserves estimated in January 2008 as 1.64 trillion m 3 (Oil and Gas Journal)
Canadian Coal Bed Methane Map
Canadian CBM First Canadian commercial CBM production in 2003 in the Horseshoe Canyon formation in Alberta, World s largest deposit of dry coal, meaning little water is produced with the natural gas. Water handling costs are low and natural gas is produced soon after well completion. More typically, CBM formations contain large amounts of water and coals must be dewatered to maximize gas production.
Location Reserve Horseshoe Canyon 1.04 Pembina (including Ardley) Mannville 4.76 Alberta/BC Foothills (Gates/Mist Mtn) Coal Bed Methane Trillion m 3 0.84 3.7 Alberta s Western Canadian Sedimentary Basin is underlain by numerous, stacked coal seams permeated with methane They contain twice the amount of gas as all of the CBM basins in the continental United States combined
Location of Probable Primary CBM Potential Economically Recoverable CBM Reserves in Canada (trillion cubic metres) Alberta Energy and Utilities Board (2004) estimated the greatest reserves were to be found in Alberta, followed by British Columbia and Nova Scotia An excellent summary on coal and CBM for 22 countries can be found in the methane to markets reports see bibliography Alberta (3.68) British Columbia (2.55) Nova Scotia (1.42)
Enhanced Extraction of CBM (1) Unfortunately, Canadian development has been restricted due to the relatively low permeability of Alberta coals Nitrogen fracturing treatments can stimulate natural fractures in the coals without damaging the fragile, dry coal formations The alternative method is to fracture (fracing) the seams using liquids or proprietary agents, improvements of up to 35% production have been claimed
Enhanced Extraction of CBM (2) Enhanced CBM would significantly improve recovery while sequestering CO 2, and does not require very pure CO 2 (flue gas will do) This process works by displacing sorbed CH 4 molecules with CO 2 molecules on the coal s carbon (~ 1:10 to 1:1 ratio depending on coal rank)
Enhanced Extraction of CBM (3) The optimum mix of N 2 and CO 2 in the injection gas depends on the technical and commercial requirements of the process If CO 2 storage/volume is the main consideration, the injection gas should be 100% CO 2 If rapid maximization of hydrocarbon gas recovery is the goal the injected gas should be 100% N 2 Generally high-rank coals are more favourable for CO 2 storage because methane displacement efficiency increases with rank, and the permeability is less affected by the swelling of the coal
Canadian CO 2 Storage Possibilities and Capacity Unmineable Coal Beds: 2 billions tonnes Depleted Oil & Gas Reservoirs: 3.7 billion tonnes Deep Saline Formations: more than 100 billion tonnes With proper geologic selection and project management, 99% of injected CO 2 will likely be retained for 1000 years (IPCC Special Report on CCS, 2005)
GHG Emission Sources/Sedimentary Basins in Canada Ideal geology in Western Canada for underground storage of CO 2 More than 50% of More than 50% of Canada s CO 2 emissions, many of them large point sources, are in close proximity to these storage locations
CANMET CO 2 Storage R&D 1. Developing monitoring, measurement and verification (MMV): CO 2 storage tool and protocols Monitoring of CO 2 storage in various geological formations 2. Assessing storage integrity Assessing the containment and potential for leakage of stored CO 2 in deep saline aquifers and depleted hydrocarbon reservoirs, and applying them to a Canadian case study 3. Characterization of and capacity estimates for saline aquifers Develop methodologies for estimating storage capacity in aquifers 4. Effects of impurities in the CO 2 stream on surface capture and transport facilities, and subsurface environments
Canadian Storage Projects - Overview Commercial Weyburn-Midale (EnCana-Apache) EOR (IEA GHG Weyburn CO 2 Monitoring and Storage Project) Vikor project, Joffre (Penn West Energy) - EOR Pilot Pembina - Cardium (PennWest Energy) EOR Swan Hills (Devon Energy) EOR Enchant (Penn West) - EOR Zama (Apache) Acid gas injection CSEMP CO 2 Sequestration and Enhanced Methane Production (Suncor, Enerplus Resources) -ECBM Big Fenn ECBM Acid Gas Injection Approximately 50 sites in AB and BC Storage sites in depleted fields and saline aquifers Approximately 1.5Mt have been stored so far
Project Overview CSEMP CO 2 Sequestration and Enhanced Methane Production Pilot Extended pilot to test coal seam response to CO 2 injection, determine CO 2 storage parameters, evaluate ECBM production potential and establish storage, monitoring and verification parameters Determine baseline production of CBM from coals at the pilot location Store CO 2 within coal strata and measure storage effects in the coal Determine the effect of CO 2 injection and storage on CBM production Assess economics of the collection of CO 2 and injection into coals as a longterm storage method for GHG emissions reduction Monitor and trace the path of CO 2 movement by geochemical and geophysical methods; tiltmeter array installed Initiated in late-2001, site near Red Deer discounted due to low permeability, new one is in Pembina field in Ardley Coal
Project Area Located in the Pembina field in west- central Alberta The zone of interest is the Lower Ardleycoal at depths of greater than 400 mkb Thickness of 10m
Results of Tests Successful completion of micro-pilot test -met all technical objectives 192 tonnes of CO 2 was injected CO 2 soak for 30 days Injectivity decreased during injection but permeability rebounded after an extended production period of 1 month Production for 60 days measuring gas composition, pressures and flow rates History matching indicates a significant methane production enhancement compared to primary production Substantial CO 2 storage in the coal seam is feasible in a multi-well project
Looking Forward It is proposed to test ECBM (Enhanced Coal Bed Methane) technology with CO 2 storage on a low rank (lignite) coal resource in the Xinjiang province of China. There are significant low rank coal deposits in both China and Canada CanmetEnergy proposal submission to Asia Pacific Partnership: Carbon Capture and Storage Program, for funding (March 2008). Alberta Research Council is working with Petromin (a Canadian company) and PetroChina, China United Coalbed Methane Company Ltd. to pursue a multi-well ECBM pilot that builds from the CIDA-China project.
New ECBM Test Sites in China New Site Shanxi Province Xingjiang Province Qinshui Basin Low Rank Coal Low Gas Content New Site
Environmental Issues (Water) Typically, CBM formations contain large amounts of water and coals must be dewatered to maximize gas production This water must be disposed of, and may contain This water must be disposed of, and may contain high Na levels; this is of considerable interest in some states such as Wyoming and Montana for development of the Powder River Basin CBM resource
Environmental Issues (Water) Governor Vetoes HB 575 Coal Bed Methane Water Welfare April 29, 2009 in 2009 Legislative Session, Brian Schweitzer, Economy & Business, Energy, Environment, Montana, Water Quality Montana Governor Brian Schweitzer (D) told Gasification News that the coal industry should view the CO 2 challenge as a phenomenal opportunity and to stop denying the problem. As the governor of the U.S. state that has the most coal, Schweitzer gives this advice to the coal industry: If we in the coal business say that [those who believe CO 2 causes global warming] are crazy, and you dig in and plan to do nothing about the carbon in coal, then you should learn a whole lot about nukes, because that will be taking over the electrical generation portfolio of the United States. You ought to get used to seeing wind turbines in your front yard. Gasification News, October 2007
Environmental Issues Rural landowners are focused on two main issues: Protecting their shallow aquifers and water wells from damage during drilling and completion operations. Reducing environmental footprint from CBM development --including well density, road access, cumulative impacts and noise emitted from compressors.
Environmental Issues A Horror Story A family receives $13,000 for access to the field to allow drilling for gas Suddenly, the well goes bad, the animals refuse to drink the water, and sinks and toilets are as clean as if a strong cleaner had been used. Showering produces intense pain in the eyes. William Marsden (author and journalist) in Oil Sands, Stupid to the Last Drop, Knoff Canada, 2007
Other Reasons for Assessing Methane Emissions from Mines Fugitive methane, emitted from coal mines worldwide represents ~8% of the world s anthropogenic methane emissions or ~17% of total anthropogenic greenhouse gases Su et al., PECS, 2005 A similar type of problem exists with coal fires; Dr. Prakash estimates that putting out Chinese coal fires alone would cut CO 2 emissions equivalent to the volume produced by all US automobiles in a year or 2-3% of world s annual CO 2 production A. Prakash, University of Alaska, Fairbanks
Conclusions Coal Bed Methane is a resource which Canada and other countries will need in future While considerable extraction is already occurring, enhanced coal bed methane technology is needed to fully exploit the resources Ideally, this can also be combined with CO 2 storage and sequestration However, it will be essential to minimize environmental problems associated with the extraction of this valuable resource
Acknowledgments Mr. David Ryan, Program Co-ordinator CO 2 CCS Program, CanmetENERGY, Ottawa (email: dryan@nrcan.gc.ca) Dr. William Gunter, PrincipalConsultant. Alberta Research Council (email: gunter@arc.ab.ca) The author would also like to thank Professor Prakash for permission to quote from his web site and Mr. William Marsden to paraphrase the section of his book dealing with CBM.
Bibliography http://www.canadianenergyadvantage.com/natural-gas-coalbedmethane.php http://waterquality.montana.edu/docs/methane/cbmfaq.pdf http://www.methanetomarkets.org/resources/coalmines/overview.htm Gasification News, Vol. 10, no. 16, October 2007 (Interview by Suzanne McElligott). Su, S., et al., An Assessment of Mine Methane Mitigation and Utilization Technologies, Progress in Energy and Combustion Science, 31, 123-170, 2005. http://www.gi.alaska.edu/~prakash/coalfires/global_distribution.html William Marsden, Stupid to the Last Drop How Alberta is Bringing Environmental Armageddon to Canada (And Doesn t Seem to Care), pp. 199-212, Knoff Canada, 2007.