Analysis of Nitrogen Stimulation Technique in Shallow Coalbed-Methane Formations
- Antonin Settari (Taurus Reservoir Solutions) | Robert C. Bachman (Taurus Reservoir Solutions) | Paul Bothwell (Energy Resources Conservation Board of Alberta)
- Document ID
- Society of Petroleum Engineers
- SPE Production & Operations
- Publication Date
- May 2012
- Document Type
- Journal Paper
- 185 - 194
- 2012. Society of Petroleum Engineers
- 5.8.3 Coal Seam Gas, 4.8 Facilities and Construction Project Management, 5.3.4 Integration of geomechanics in models, 5.6.3 Pressure Transient Testing
- Facilities and Construction Project Management
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Nitrogen (N2) stimulation has become the preferred technique for stimulation of coal seams in the Horseshoe Canyon play in Alberta. It consists of stimulating each seam by pumping at very high rates for short time (2-4 minutes). Because the coal is producible at shallow depths, the Energy Resource Conservation Board (ERCB) has been developing and updating regulatory guidelines that aim to protect the freshwater supply.
This study was undertaken to improve the understanding of the process and provide recommendations on the regulatory guidelines for shallow depth (less than 200 m). The study was provided with extensive data from the industry (more than 20,000 fractures in more than 2,000 wells) and has carried out several types of analyses to estimate fracture orientation and dimensions and their dependence on N2-injection rate and duration and on reservoir parameters. This included statistical analysis of large amounts of surface pressure data, pressure-transient analysis (PTA) of downhole pressure data, analysis of fracture-mapping data, and conceptual simulations of the injection process using coupled reservoir and geomechanical models. Coupled geomechanical modeling provided a realistic physical model of the process (in comparison with conventional models). Stress dependence of coal permeability and permeability anisotropy were shown to be the controlling mechanisms. This model was then used to investigate height-growth mechanisms.
After considering the results of the analysis, its limitations, uncertainties in geological description of the coal and shale sequences, available case histories, and other factors, recommendations were made for modifications, resulting in the revised ERCB Directive 27, Shallow Fracturing Operations--Restricted Operations, released 14 August 2009.
|File Size||2 MB||Number of Pages||10|
Bagheri, M.A. and Settari, A. 2008. Modeling of Geomechanics in NaturallyFractured Reservoirs. SPE Res Eval & Eng 11 (1):108-118. SPE-93083-PA. http://dx.doi.org/10.2118/93083-PA.
Economides, M.J. and Martin, T. ed. 2007. Modern Fracturing--EnhancingNatural Gas Production. Houston: Energy Tribune Publishing.
Economides, M.J. and Nolte, K.G. 2000. Reservoir Stimulation, thirdedition. New York City: John Wiley & Sons.
Enever, J.R.E. and Henning, A. 1997. The relationship between permeabilityand effective stress for Australian coals and its implications with respect tocoalbed methane exploration and reservoir modelling. Paper presented at theInternational Coalbed Symposium, Tuscaloosa, Alabama, USA, 12-16 May.
ERCB. 2009. Directive 027: Shallow Fracturing Operations--RestrictedOperations, revised edition. Technical directive, Energy Resources ConservationBoard, Calgary, Alberta (14 August 2009). http://www.ercb.ca/docs/documents/directives/Directive027.pdf.
Foo, D. and Weaver, V. 2007. Paramount Chain CBM Project: Case Studyof Shallow Operations. Technical presentation, Petroleum Technology AllianceCanada (PTAC), Calgary.
GEOSIM User Manual. 2009. Calgary, Alberta: Taurus Reservoir SolutionsLtd.
Gidley, J.L., Holditch, S.A., Nierode, D.E., and Veatch, R.W. Jr. 1989.Recent Advances in Hydraulic Fracturing, No. 12. Richardson, Texas, USA:Monograph Series, SPE.
Gu, F. 2009. Simulation of CO2 Sequestration and Enhanced Coalbed MethaneRecovery with Reservoir and Geomechanical Coupling. Department of Civil andEnvironmental Engineering, University of Alberta, Calgary.
Hannan, S.S. and Nzekwu, B.I. 1992. AOSTRA Mini-Frac Manual, Series#13. Calgary: Alberta Oil Sands Technology & Research Authority.
Hoch, O.F. 2005. The Dry Coal Anomaly--The Horseshoe Canyon Formation ofAlberta, Canada. Paper SPE 95872 presented at the SPE Annual TechnicalConference and Exhibition, Dallas, 9-12 October. http://dx.doi.org/10.2118/95872-MS.
Law, D.H.-S., van der Meer, L.G.H., and Gunter, W.D. 2002. NumericalSimulator Comparison Study for Enhanced Coalbed Methane Recovery Processes,Part I: Pure Carbon Dioxide Injection. Paper SPE 75669 presented at the SPE GasTechnology Symposium, Calgary, 30 April-2 May. http://dx.doi.org/10.2118/75669-MS.
Nassir, M., Settari, A., and Wan, R.G. 2010. Modeling Shear DominatedHydraulic Fracturing as a coupled fluid-solid interaction. Paper SPE 131736presented at the International Oil and Gas Conference and Exhibition in China,Beijing, 8-10 June. http://dx.doi.org/10.2118/131736-MS.
Palmer, I. and Mansoori, J. 1996. How Permeability Depends on Stress andPore Pressure in Coalbeds: A New Model. Paper SPE 36737 presented at the SPEAnnual Technical Conference and Exhibition, Denver, 6-9 October. http://dx.doi.org/10.2118/36737-MS.
Rieb, B.A. and Leshchyshyn, T.T. 2005. The Production Success of ProppantStimulation on Horseshoe Canyon Coalbed Methane and Sandstone Commingled Wells.Paper SPE 96864 presented at the SPE Annual Technical Conference, Dallas, 9-12October. http://dx.doi.org/10.2118/96864-MS.
Settari, A. and Walters, D.A. 2001. Advances in Coupled Geomechanical andReservoir Modeling With Applications to Reservoir Compaction. SPE J.6 (3): 334-342. SPE-51927-PA. http://dx.doi.org/10.2118/51927-MS.
Settari, A., Sullivan, R.B., and Bachman, R.C. 2002. The Modeling ofthe Effect of Water Blockage and Geomechanics in Waterfrac. Paper SPE 77600presented at the SPE Annual Technical Conference and Exhibition, San Antonio,Texas, USA, 29 September-2 October. http://dx.doi.org/10.2118/77600-MS.
Settari, A., Sullivan, R.B., Rother, R.J., and Skinner, T.K. 2009.Comprehensive coupled modeling analysis of stimulations and post-fracproductivity - case study of a tight gas field in Wyoming. Paper SPE 119394presented at the SPE Hydraulic Fracturing Technology Conference, The Woodlands,Texas, USA, 19-21 January. http://dx.doi.org/10.2118/119394-MS.
Settari, A., Warren, G.M., Jacquemont, J., Bieniawski, P., and Dussaud, M. 1999. Brine Disposal Into a Tight Stress-Sensitive Formation atFracturing Conditions: Design and Field Experience. SPE Res Eval &Eng 2 (2): 186-195. SPE 56001. http://dx.doi.org/10.2118/56001-PA.
Settari, A.T., Bachman, R.C., and D.A.Walters. 2005. How ToApproximate Effects of Geomechanics in Conventional Reservoir Simulation. PaperSPE 97155 presented at the SPE Annual Technical Conference and Exhibition,Dallas, 9-12 October. http://dx.doi.org/10.2118/97155-MS.
Shi, J.-Q. and Durucan, S. 2005. Gas Storage and Flow in Coalbed Reservoirs:Implementation of a Bidisperse Pore Model for Gas Diffusion in Coal Matrix.SPE Res Eval & Eng 8 (2): 169-175. SPE-84342-PA. http://dx.doi.org/10.2118/84342-PA.
Taurus Reservoir Solutions Ltd. 2008. Shallow Nitrogen Fracturing Dimensionsand Groundwater Protection: Evaluation of the ERCB Directive 27. Final Report,Alberta Energy Resources Conservation Board, Calgary (8 October 2008).