Journal Home > Volume 3 , Issue 2
Advances in Geo-Energy Research 2019, 3(2): 165-174 https://doi.org/10.26804/ager.2019.02.06
Original Article | Open Access | Issue | Published: 08 March 2019

Experimental and numerical simulation of water adsorption and diffusion in shale gas reservoir rocks

Show Author's Information Weijun Shen1 ( ),  Xizhe Li2,  Abdullah Cihan3,  Xiaobing Lu1,  Xiaohua Liu2
Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, P. R. China
PetroChina Research Institute of Petroleum Exploration and Development, Beijing 100083, P. R. China
Energy Geosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
Keywords:
water retention, capillary condensation, Shale gas, GAB model, water adsorption and diffusion
Cite this article:
Shen W, Li X, Cihan A, et al. Experimental and numerical simulation of water adsorption and diffusion in shale gas reservoir rocks. Advances in Geo-Energy Research, 2019, 3(2): 165-174. https://doi.org/10.26804/ager.2019.02.06
Download citation
EndNote(RIS)
BibTeX

765

Views

96

Downloads

Citations

52

Crossref

0

WoS

63

Scopus

N/A

CSCD

Abstract Full text About this article

Despite the success of deep horizontal drilling and hydraulic fracturing in yielding large production increases from unconventional shale gas reservoirs, uncertainties associated with basic transport processes require understanding in order to improve efficiency and minimize environmental impacts. The hydraulic fracturing process introduces large volumes of water into shale gas reservoirs, most of which remains unrecoverable and interferes with gas production. In this study, the water adsorption and diffusion measurements of the Longmaxi Formation shale were conducted at 30 ℃ and 50 ℃ for relative humidities from 11.1% to 97.0%. Based on the experiment, a computational model based on the Maxwell-Stefan diffusion equation was constructed to analyze water adsorption and diffusion in shale rocks, and the Guggenheim-Anderson-de Boer (GAB) isotherm for gas adsorption was included in the model. The results show that water adsorption isotherms of shales belong to type Ⅱ curve, including the monolayer, multilayer adsorption and capillary condensation, and the GAB model can be used to describe the water adsorption process in shale rocks. With the increasing of relative pressure, the water adsorption of shale increases, and the organic carbon content and temperature strengthen the water adsorption in shale. The capillary pressure can reach the order of several hundreds of MPa after the hydraulic fracturing process, and it results in a large amount of fracturing fluid retained in shale gas reservoirs. Furthermore, the simulation of water adsorption and diffusion in shale rocks is less than the experimental value, which further indicates that capillary condensation occurs in shale rocks.


menu
Abstract
Full text
Outline
About this article

Experimental and numerical simulation of water adsorption and diffusion in shale gas reservoir rocks

Show Author's information Weijun Shen1 ( ), Xizhe Li2, Abdullah Cihan3, Xiaobing Lu1, Xiaohua Liu2
Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, P. R. China
PetroChina Research Institute of Petroleum Exploration and Development, Beijing 100083, P. R. China
Energy Geosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA

Abstract

Despite the success of deep horizontal drilling and hydraulic fracturing in yielding large production increases from unconventional shale gas reservoirs, uncertainties associated with basic transport processes require understanding in order to improve efficiency and minimize environmental impacts. The hydraulic fracturing process introduces large volumes of water into shale gas reservoirs, most of which remains unrecoverable and interferes with gas production. In this study, the water adsorption and diffusion measurements of the Longmaxi Formation shale were conducted at 30 ℃ and 50 ℃ for relative humidities from 11.1% to 97.0%. Based on the experiment, a computational model based on the Maxwell-Stefan diffusion equation was constructed to analyze water adsorption and diffusion in shale rocks, and the Guggenheim-Anderson-de Boer (GAB) isotherm for gas adsorption was included in the model. The results show that water adsorption isotherms of shales belong to type Ⅱ curve, including the monolayer, multilayer adsorption and capillary condensation, and the GAB model can be used to describe the water adsorption process in shale rocks. With the increasing of relative pressure, the water adsorption of shale increases, and the organic carbon content and temperature strengthen the water adsorption in shale. The capillary pressure can reach the order of several hundreds of MPa after the hydraulic fracturing process, and it results in a large amount of fracturing fluid retained in shale gas reservoirs. Furthermore, the simulation of water adsorption and diffusion in shale rocks is less than the experimental value, which further indicates that capillary condensation occurs in shale rocks.

Keywords: water retention, capillary condensation, Shale gas, GAB model, water adsorption and diffusion

References(40)

Adamson, A.W., Gast, A.P. Physical Chemistry of Surfaces. New York, USA, John Wiley & Sons, 1967.

Ai-Awad, M.N.J., Smart, B.G.D. Characterization of shale-drilling fluid interaction mechanisms related to wellbore instability. J. King Saud Univ. Eng. Sci. 1996, 8(2): 187-214.
DOI Google Scholar

Anderson, R.B. Modifications of the Brunauer, Emmett, and Teller equation. J. Am. Chem. Soc. 1946, 68(4): 686-691.
DOI Google Scholar

Boer, J.H. The Dynamic Character of Adsorption. Oxford, UK, Clarendon Press, 1953.
Chang, M., Zhou, J., Chenevert, M.E., et al. The impact of shale preservation on the petrophysical properties of organic-rich shales. Paper SPE166419 Presented at SPE Annual Technical Conference and Exhibition, New Orleans, Louisiana, 30 September-2 October, 2013.

Chenevert, M.E. Shale control with balanced-activity oil-continuous muds. J. Pet. Technol. 1970, 22(10): 1309-1316.
DOI Google Scholar
Chenevert, M.E., Pernot, V. Control of shale swelling pressures using inhibitive water-base muds. Paper SPE49263 Presented at SPE Annual Technical Conference and Exhibition, New Orleans, Louisiana, 27-30 September, 1998.https://doi.org/10.2118/49263-MS
DOI

Cheng, Y. Impact of water dynamics in fractures on the performance of hydraulically fractured wells in gas shale reservoirs. J. Can. Pet. Technol. 2012, 51(2): 143-151.
DOI Google Scholar
COMSOL. Sweden, COMSOL Inc., 2015.

Dehghanpour, H., Lan, Q., Saeed, Y., et al. Spontaneous imbibition of brine and oil in gas shales: Effect of water adsorption and resulting microfractures. Energy Fuels 2013, 27(6): 3039-3049.
DOI Google Scholar

Foo, K.Y., Hameed, B.H. Insights into the modeling of adsorption isotherm systems. Chem. Eng. J. 2010, 156(1): 2-10.
DOI Google Scholar

Frenkel, J. Kinetic Theory of Liquids. Oxford, UK, Oxford University Press, 1946.

Gao, S., Hu, Z., Guo, W., et al. Water absorption characteristics of gas shale and the fracturing fluid flowback capacity. Natural Gas Industry 2013, 33(12): 71-76. (in Chinese)
Google Scholar

Ge, H., Yang, L., Shen, Y., et al. Experimental investigation of shale imbibition capacity and the factors influencing loss of hydraulic fracturing fluids. Pet. Sci. 2015, 12(4): 636-650.
DOI Google Scholar

Genuchten, M.T.V. A closed-form equation for predicting the hydraulic conductivity of unsaturated soils. Soil Sci. Soc. Am. J. 1980, 44(5): 892-898.
DOI Google Scholar

Greenspan, L. Humidity fixed-points of binary saturated aqueous solutions. J. Res. Nat. Bur. Stand. Sect. A 1977, 81(1): 89-96.
DOI Google Scholar

Guggenheim, E.A. Application of Statistical Mechanics. Oxford, UK, Clarendon Press, 1966.

Halsey, G.D.J. Physical adsorption on non-uniform surfaces. J. Chem. Phys. 1948, 16(10): 931-937.
DOI Google Scholar

Hill, T.L. Advances in catalysis. J. Chem. Phys. 1949, 17: 580-668.
Google Scholar
International Energy Agency. World Energy Outlook 2018. Paris, IEA/OECD, 2018.
King, G.E. Thirty years of gas shale fracturing: What have we learned? Paper SPE 133456 Presented at SPE Annual Technical Conference and Exhibition, Florence, Italy, 19-22 September, 2010.https://doi.org/10.2118/133456-MS
DOI

Li, J., Li, X., Wu, K., et al. Thickness and stability of water film confined inside nanoslits and nanocapillaries of shale and clay. Int. J. Coal Geol. 2017, 179: 253-268.
DOI Google Scholar

Li, Q., Xing, H., Liu, J., et al. A review on hydraulic fracturing of unconventional reservoir. Petroleum 2015, 1(1): 8-15.
DOI Google Scholar

Makhanov, K., Habibi, A., Dehghanpour, H., et al. Liquid uptake of gas shales: A workflow to estimate water loss during shut-in periods after fracturing operations. J. Unconv. Oil Gas Res. 2014, 7: 22-32.
DOI Google Scholar
Odusina, E.O., Sondergeld, C.H., Rai, C.S. An NMR study of shale wettability. Paper SPE 147371 Presented at SPE Canadian Unconventional Resources Conference, Calgary, Alberta, Canada, 15-17 November, 2011.https://doi.org/10.2118/147371-MS
DOI

Prost, R., Benchara, A., Huard, E. State and location of water adsorbed on clay minerals: Consequences of the hydration and swelling-shrinkage phenomena. Clays Clay Miner. 1998, 46 (2): 117-131.
DOI Google Scholar

Qi, R., Ning, Z., Wang, Q., et al. Sorption measurements of moistureequilibrated shale with the consideration of water vapor pressure. Sci. Sin. 2018, 48(5): 524-536.
DOI Google Scholar

Shang, S., Horne, R.N., Jr, H.J.R. Water vapor adsorption on geothermal reservoir rocks. Geothermics 1995, 24(4): 523-540.
DOI Google Scholar

Shen, W., Li, X., Lu, X., et al. Experimental study and isotherm models of water vapor adsorption in shale rocks. J. Nat. Gas Sci. Eng. 2018, 52: 484-491.
DOI Google Scholar

Shen, W., Li, X., Xu, Y., et al. Gas flow behavior of nanoscale pores in shale gas reservoirs. Energies 2017, 10(6): 1-12.
DOI Google Scholar

Shen, W., Xu, Y., Li, X., et al. Numerical simulation of gas and water flow mechanism in hydraulically fractured shale gas reservoirs. J. Nat. Gas Sci. Eng. 2016, 35: 726-735.
DOI Google Scholar

Shen, W., Zheng, L., Oldenburg, C.M., et al. Methane diffusion and adsorption in shale rocks: A numerical study using the dusty gas model in Tough2/EOS7C-ECBM. Transp. Porous Media 2018, 123(3): 521-531.
DOI Google Scholar

Shen, Y., Ge, H., Su, S., et al. Imbibition characteristic of shale gas formation and water-block removal capability. Sci. Sin-Phys. Mech. Astron. 2017, 47: 114609.
DOI Google Scholar
Tandanand, S. Moisture adsorption rate and strength degradation of Illinois shales. Paper ARMA-85-0591-1 Presented at The 26th U.S. Symposium on Rock Mechanics (USRMS), Rapid City, South Dakota, 26-28 June, 1985.

Tien, C. Adsorption Calculations and Modeling. Boston, USA, Butterworth-Heinemann, 1994.
DOI

Tokunaga, T.K., Shen, W., Wan, J., et al. Water saturation relations and their diffusion-limited equilibration in gas shale: Implications for gas flow in unconventional reservoirs. Water Resour. Res. 2017, 53(11): 9757-9770.
DOI Google Scholar

Wei, M., Duan, Y., Fang, Q., et al. Mechanism model for shale gas transport considering diffusion, adsorption/desorption and Darcy flow. J. Cent. South Univ. 2013, 20(7): 1928-1937.
DOI Google Scholar

Wei, M., Duan, Y., Fang, Q., et al. Production decline analysis for a multi-fractured horizontal well considering elliptical reservoir stimulated volumes in shale gas reservoirs. J. Geophys. Eng. 2016, 13(3): 354-365.
DOI Google Scholar

Wu, Q., Bai, B., Ma, Y., et al. Optic imaging of two-phase-flow behavior in 1D nanoscale channels. SPE J. 2014, 19(5): 793-802.
DOI Google Scholar

Xu, J., Guo, C., Wei, M., et al. Production performance analysis for composite shale gas reservoir considering multiple transport mechanisms. J. Nat. Gas Sci. Eng. 2015, 26: 382-395.
DOI Google Scholar
Publication history
Copyright
Acknowledgements
Rights and permissions

Publication history

Received: 14 February 2019
Revised: 27 February 2019
Accepted: 04 March 2019
Published: 08 March 2019
Issue date: June 2019

Copyright

© The Author(s) 2019

Acknowledgements

This work was supported by the National Natural Science Foundation of China (NO. 11802312 and NO. U1762216), and by Open Fund (PLN201810) of State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation (Southwest Petroleum University). We also thank the support from the Youth Foundation of Key Laboratory for Mechanics in Fluid Solid Coupling Systems, Chinese Academy of Sciences.

Rights and permissions

This article is distributed under the terms and conditions of the Creative Commons Attribution (CC BY-NC-ND) license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Return