Controlling Parameters During Continuum Flow in Shale-Gas Production: A Fracture/Matrix-Modeling Approach
- Dhruvit S. Berawala (University of Stavanger) | Pål Ø. Andersen (University of Stavanger) | Jann R. Ursin (University of Stavanger (ret.))
- Document ID
- Society of Petroleum Engineers
- SPE Journal
- Publication Date
- June 2019
- Document Type
- Journal Paper
- 1,378 - 1,394
- 2019.Society of Petroleum Engineers
- shale gas production, production mechanisms, fracture-matrix modelling, adsorption, dimensionless numbers
- 20 in the last 30 days
- 42 since 2007
- Show more detail
- View rights & permissions
|SPE Member Price:||USD 10.00|
|SPE Non-Member Price:||USD 30.00|
The purpose of this paper is to investigate the main controlling factors during a continuum-flow regime in shale-gas production in the context where well-induced fractures, extending from the well perforations, improve reservoir conductivity and performance. A mathematical 1D+1D model is presented that involves a high-permeability fracture extending from a well perforation through symmetrically surrounding shale matrix with low permeability. Gas in the matrix occurs in the form of adsorbed material attached to kerogen (modeled by a Langmuir isotherm) and as free gas in the nanopores. The pressure gradient toward the fracture and well perforation causes the free gas to flow. With pressure depletion, gas desorbs out of the kerogen into the pore space and then flows to the fracture. When the pressure has stabilized, desorption and production stop.
The production of shale gas and mass distributions indicate the efficiency of species transfer between fracture and matrix. We show that the behavior can be scaled and described according to the magnitude of two characteristic dimensionless numbers: the ratio of diffusion time scales in shale and fracture, a, and the pore-volume (PV) ratio between the shale and fracture domains, ß. Fracture/matrix properties are varied systematically to understand the role of fracture/matrix interaction during production. Further, the role of fracture geometry (varying width) is investigated. Input parameters from experimental and field data in the literature are applied.
The product aß expresses how much time it takes to diffuse the gas in place through the fracture to the well compared with the time it takes to diffuse that gas from the matrix to the fracture. For aß << 1, the residence time in the fracture is of negligible importance, and fracture properties such as shape, width, and permeability can be ignored. However, if aß ≈ 1, the residence time in the fracture becomes important, and variations in all those properties have significant effects on the solution.
The model allows for intuitive interpretation of the complex shale-gas-production system. Furthermore, the current model creates a base that can easily incorporate nonlinear-flow mechanisms and geomechanical effects that are not readily found in standard commercial software, and further be extended to field-scale application.
|File Size||1001 KB||Number of Pages||17|
Alexander, T., Baihly, J., Boyer, C. et al. 2011. Shale Gas Revolution. Oilfield Rev. 23 (3): 40–55.
Andersen, P. Ø. and Evje, S. 2016. A Model for Reactive Flow in Fractured Porous Media. Chem Eng Sci 145 (12 May): 196–213. https://doi.org/10.1016/j.ces.2016.02.008.
Andersen, P. Ø., Evje, S., and Kleppe, H. 2014. A Model for Spontaneous Imbibition as a Mechanism for Oil Recovery in Fractured Reservoirs. Transp Porous Media 101 (2): 299–331. https://doi.org/10.1007/s11242-013-0246-7.
Andersen, P. Ø., Evje, S., Kleppe, H. et al. 2015. A Model for Wettability Alteration in Fractured Reservoirs. SPE J. 20 (6): 1261–1275. SPE-174555-PA. https://doi.org/10.2118/174555-PA.
Arogundade, O. and Sohrabi, M. 2012. A Review of Recent Developments and Challenges in Shale Gas Recovery. Presented at the SPE Saudi Arabia Section Technical Symposium and Exhibition, Al-Khobar, Saudi Arabia, 8–11 April. SPE-160869-MS. https://doi.org/10.2118/160869-MS.
Berawala, D. S., Ursin, J. R., and Slijepcevic, O. 2017. Sphere in Cube Grid Approach to Modelling of Shale Gas Production Using Non-Linear Flow Mechanisms. ICJEE 11 (9): 889–898.
Beskok, A. and Karniadakis, G. E. 1999. Report: A Model for Flows in Channels, Pipes, and Ducts at Micro and Nano Scales. Nanosc Microsc Therm 3 (1): 43–77. https://doi.org/10.1080/108939599199864.
Bird, R. B. 2002. Transport Phenomena. Appl. Mach. Rev. 55 (1): R1–R4. https://doi.org/10.1115/1.1424298.
Blasingame, T. A. 2008. The Characteristic Flow Behavior of Low-Permeability Reservoir Systems. Presented at the SPE Unconventional Reservoirs Conference, Keystone, Colorado, 10–12 February. SPE-114168-MS. https://doi.org/10.2118/114168-MS.
Carman, P. C. 1937. Fluid Flow Through Granular Beds. Trans. Inst. Chem. Eng. 15: 150–166.
Cipolla, C. L., Lolon, E. P., Erdle, J. C. et al. 2010. Reservoir Modeling in Shale-Gas Reservoirs. SPE Res Eval & Eng 13 (4): 638–653. SPE-125530-PA. https://doi.org/10.2118/125530-PA.
Civan, F. 2010. Effective Correlation of Apparent Gas Permeability in Tight Porous Media. Transp Porous Media 82 (2): 375–384. https://doi.org/10.1007/s11242-009-9432-z.
Civan, F., Rai, C. S., and Sondergeld, C. H. 2011. Shale-Gas Permeability and Diffusivity Inferred by Improved Formulation of Relevant Retention and Transport Mechanisms. Transp Porous Media 86 (3): 925–944. https://doi.org/10.1007/s11242-010-9665-x.
Du, C. M., Zhang, X., Zhan, L. et al. 2010. Modeling Hydraulic Fracturing Induced Fracture Networks in Shale Gas Reservoirs as a Dual Porosity System. Presented at the InternationalOil and Gas Conference and Exhibition in China, Beijing, 8–10 June. SPE-132180-MS. https://doi.org/10.2118/132180-MS.
Hill, D. G. and Nelson, C. 2000. Gas Productive Fractured Shales: An Overview and Update. Gas Tips 6 (2): 4–13.
Ho, C. K. and Webb, S. W. eds. 2006. Gas Transport in Porous Media, Vol. 20. Dordrecht, The Netherlands: Springer Netherlands.
Hoteit, H. and Firoozabadi, A. 2008. An Efficient Numerical Model for Incompressible Two-Phase Flow in Fractured Media. Adv Water Resour 31 (6): 891–905. https://doi.org/10.1016/j.advwatres.2008.02.004.
Javadpour, F. 2009. Nanopores and Apparent Permeability of Gas Flow in Mudrocks (Shales and Siltstone). J Can Pet Technol 48 (8): 16–21. PETSOC-09-08-16-DA. https://doi.org/10.2118/09-08-16-DA.
Javadpour, F., Fisher, D., and Unsworth, M. 2007. Nanoscale Gas Flow in Shale Gas Sediments. J Can Pet Technol 46 (10): 55–61. PETSOC-07-10-06. https://doi.org/10.2118/07-10-06.
Karimi-Fard, M., Durlofsky, L. J., and Aziz, K. 2003. An Efficient Discrete Fracture Model Applicable for General Purpose Reservoir Simulators. Presented at the SPE Reservoir Simulation Symposium, Houston, 3–5 February. SPE-79699-MS. https://doi.org/10.2118/79699-MS.
Klinkenberg, L. J. 1941. The Permeability of Porous Media to Liquids and Gases. API-41-200.
Knudsen, M. 1909. Die Gesetze der Molekularströmung und der inneren Reibungsströmung der Gase durch Röhren (The Laws of Molecular and Viscous Flow of Gases Through Tubes). Annals of Physics 333 (1): 75–130. https://doi.org/10.1002/andp.19093330106.
LeVeque, R. J. 2002. Finite Volume Methods for Hyperbolic Problems, Vol. 31. Cambridge, UK: Cambridge University Press.
Mainguy, M. and Ulm, F. J. 2001. Coupled Diffusion-Dissolution Around a Fracture Channel: The Solute Congestion Phenomenon. Transp Porous Media 45 (3): 479–495. https://doi.org/10.1023/A:1012096014084.
Martin, J. P., Hill, D. G., Lombardi, T. E. et al. 2010. A Primer on New York’s Gas Shales. Proc., Fieldtrip Guidebook for the 80th Annual Meeting of the New York State Geological Association, Lake George, New York, 24–26 September, A1–A32.
MATLAB is a registered trademark of The MathWorks, Inc., Natick, Massachusetts.
Moridis, G. J., Blasingame, T. A., and Freeman, C. M. 2010. Analysis of Mechanisms of Flow in Fractured Tight-Gas and Shale-Gas Reservoirs. Presented at the SPE Latin American and Caribbean Petroleum Engineering Conference, Lima, Peru, 1–3 December. SPE-139250-MS. https://doi.org/10.2118/139250-MS.
Samandarli, O., Al Ahmadi, H. A., and Wattenbarger, R. A. 2011. A New Method for History Matching and Forecasting Shale Gas Reservoir Production Performance With a Dual Porosity Model. Presented at the North American Unconventional Gas Conference and Exhibition, The Woodlands, Texas, 14–16 June. SPE-144335-MS. https://doi.org/10.2118/144335-MS.
Schlumberger-GeoQuest. 2009. Eclipse Reservoir Simulator, Technical Description.
Strang, G. 1968. On the Construction and Comparison of Difference Schemes. SIAM Journal on Numerical Analysis 5 (3): 506–517. https://doi.org/10.1137/0705041.
Tecklenburg, J., Neuweiler, I., Dentz, M. et al. 2013. A Non-Local Two-Phase Flow Model for Immiscible Displacement in Highly Heterogeneous Porous Media and its Parametrization. Adv Water Resour 62C (December): 475–487. https://doi.org/10.1016/j.advwatres.2013.05.012.
van Golf-Racht, T. D. 1982. Fundamentals of Fractured Reservoir Engineering, Vol. 12, first edition. Amsterdam: Elsevier Science.
Warren, J. E. and Root, P. J. 1963. The Behavior of Naturally Fractured Reservoirs. SPE J. 3 (3): 245–255. SPE-426-PA. https://doi.org/10.2118/426-PA.
Yao, J., Sun, H., Fan, D. Y. et al. 2013. Numerical Simulation of Gas Transport Mechanisms in Tight Shale Gas Reservoirs. Pet Sci 10 (4): 528–537. https://doi.org/10.1007/s12182-013-0304-3.
Yu, W., Sepehrnoori, K., and Patzek, T. W. 2016. Modeling Gas Adsorption in Marcellus Shale With Langmuir and BET Isotherms. SPE J. 21 (2): 589–600. SPE-170801-PA. https://doi.org/10.2118/170801-PA.