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Transport in Porous Media

, Volume 124, Issue 1, pp 73–90 | Cite as

A Novel Method for Gas–Water Relative Permeability Measurement of Coal Using NMR Relaxation

  • Xiaoxiao Sun
  • Yanbin Yao
  • Nino Ripepi
  • Dameng Liu
Article
  • 196 Downloads

Abstract

Using the conventional volumetric method in unsteady-state relative permeability measurements for unconventional gas reservoirs, such as coal and gas shale, is a significant challenge because the movable water volume in coal or shale is too small to be detected. Moreover, the dead volume in the measurement system adds extra inaccuracy to the displaced water determination. In this study, a low-field nuclear magnetic resonance (NMR) spectrometer was introduced into a custom-built relative permeability measurement apparatus, and a new method was developed to accurately quantify the displaced water, avoiding the drawback of the dead volume. The changes of water in the coal matrix and cleats were monitored during the unsteady-state displacement experiments. Relative permeability curves for two Chinese anthracite and bituminous coals were obtained, matching the existing research results from the Chinese coalbed methane area. Moreover, the influences of confining pressure on the shape of the relative permeability curve were evaluated. Although uncertainties and limits exist, the NMR-based method is a practical and applicable method to evaluate the gas/water relative permeability of ultra-low permeability rocks.

Keywords

Coalbed methane Relative permeability Unconventional gas reservoir NMR 

List of symbols

A

Amplitude index

Aad

Air-dry-based ash yield

Fcad

Air-dry-based fixed carbon content

fw

Fractional flow of water in outlet stream

I

Volume percentages of inertinite in coal maceral composition

Ir

Relative injectivity

krg

Relative permeability of gas

krw

Relative permeability of water

L

Volume percentages of liptinite in coal maceral composition

Mad

Air-dry-based moisture content

MM

Volume percentage of minerals on a dry basis

Np

Cumulative water produced

P1,2,3

Peaks in T2 distribution spectra

Pinlet

Inlet gas pressure

Poutlet

Outlet gas pressure

qt

Total flow rate or gas injection rate

Ro

Mean maximum vitrinite reflectance in oil

S/V

Surface-to-volume ratio

Sg2

Outlet gas saturation

Sgcross

Gas saturation at crossing points

Sgi

Initial gas saturation

Swr

Irreducible water saturation

T0

Total amplitude of T2 at the initial displacement time

T2

Proton NMR transverse relaxation time

Tt

Total amplitude of T2 at different displacement times

V

Volume percentages of vitrinite in coal maceral composition

Wi

Cumulative gas injected

Greek symbols

P

Pressure difference

Wig

Injection gas volume under inlet gas pressure at a given interval value

ρ2

Surface relaxivity

μg

Gas viscosities

μw

Water viscosities

Subscripts

B

Bulk relaxation

S

Surface relaxation

Notes

Acknowledgements

We acknowledge financial support from the National Natural Science Foundation of China (41472137), the National Major Research Program for Science and Technology of China (2016ZX05043-001), the Fundamental Research Funds for the Central Universities (2652016124) and China Scholarship Council (201606400013).

Compliance with Ethical Standards

Conflict of interest

The authors declare that they have no conflict of interest.

Data Availability

The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.

References

  1. Alexis, D.A., Karpyn, Z.T., Ertekin, T., Crandall, D.: Fracture permeability and relative permeability of coal and their dependence on stress conditions. J. Unconv. Oil Gas Res. 10, 1–10 (2015)CrossRefGoogle Scholar
  2. Brooks, R.H., Corey, A.T.: Properties of porous media affecting fluid flow. J. Irrig. Drain. Div. 6, 61–88 (1966)Google Scholar
  3. Cai, Y., Liu, D., Pan, Z., Che, Y., Liu, Z.: Investigating the effects of seepage-pores and fractures on coal permeability by fractal analysis. Transp. Porous Med. 111, 479–497 (2016)CrossRefGoogle Scholar
  4. Chen, D., Pan, Z., Liu, J., Connell, L.D.: An improved relative permeability model for coal reservoirs. Int. J. Coal Geol. 109–110, 45–57 (2013)CrossRefGoogle Scholar
  5. Chen, D., Shi, J., Durucan, S., Korre, A.: Gas and water relative permeability in different coals model match and new insights. Int. J. Coal Geol. 122, 37–49 (2014)CrossRefGoogle Scholar
  6. Clarkson, C.R., Jordan, C.L., Gierhart, R.R., Seidle, J.P.: Production data analysis of CBM wells. In: Rocky Mountain Oil and Gas Technology Symposium, Society of Petroleum Engineers (2007)Google Scholar
  7. Coates, G.R., Xiao, L.Z., Prammer, M.G.: NMR Logging Principles and Applications. Gulf Publishing Company, Houston (1999)Google Scholar
  8. Conway, M.J., Mavor, M.J., Saulsberry, J., Barree, R.B., Schraufnagel, R.A.: Multi-phase flow properties for coalbed methane wells: a laboratory and field study. In: Low Permeability Reservoirs Symposium, Society of Petroleum Engineers (1995)Google Scholar
  9. Durucan, S., Ahsan, M., Shi, J.Q.: Two phase relative permeabilities for gas and water in selected European coals. Fuel 134, 226–236 (2014)CrossRefGoogle Scholar
  10. Firoozabadi, A., Aziz, K.: Relative permeabilities from centrifuge data. J. Can. Pet. Technol. 30, 2–4 (1988)Google Scholar
  11. Gash, B.W.: Measurement of “rock properties” in coal for coalbed methane production. In: SPE Annual Technical Conference and Exhibition, Society of Petroleum Engineers (1991)Google Scholar
  12. Guo, R., Kantzas, A.: Assessing the water uptake of Alberta coal and the impact of CO2 injection with low-field NMR. J. Can. Pet. Technol. 48, 40–46 (2009)CrossRefGoogle Scholar
  13. Ham, Y.S., Kantzas, A.: Measurement of relative permeability of coal: approaches and limitations. In: CIPC/SPE Gas Technology Symposium 2008 Joint Conference, Society of Petroleum Engineers (2008)Google Scholar
  14. Ham, Y.S., Kantzas, A.: Relative permeability of coal to gas (helium, methane, and carbon dioxide) and water-result and experimental limitations. In: Canadian Unconventional Resources Conference, Society of Petroleum Engineers (2011)Google Scholar
  15. Ham, Y.S., Kantzas, A.: Measurement of relative permeability of coal to gas and water. In: SPE Unconventional Resources Conference and Exhibition-Asia Pacific, Society of Petroleum Engineers (2013)Google Scholar
  16. Honarpour, M., Mahmood, S.M.: Relative-permeability measurements: an overview. J. Pet. Technol. 40, 963–966 (1988)CrossRefGoogle Scholar
  17. Howard, J.J., Kenyon, W.E., Straley, C.: Proton-magnetic resonance and pore-size variations in reservoir sandstones. SPE Form. Eval. 8, 194–200 (1993)CrossRefGoogle Scholar
  18. Johnson, E.F., Bossler, D.P., Naumann, V.O.: Calculation of relative permeability from displacement experiments. Trans. AIME 216, 370–372 (1959)Google Scholar
  19. Kamath, J., de Zabala, E.F., Boyer, R.E.: Water/oil relative permeability endpoints of intermediate wet low permeability rocks. SPE Form. Eval. 10, 26–28 (1993)Google Scholar
  20. Kenyon, W.E., Day, P.I., Straley, C., Willemsen, J.F.: A three part study of NMR longitudinal relaxation properties of water-saturated sandstones. SPE Form. Eval. 3, 622–636 (1988)CrossRefGoogle Scholar
  21. Li, K.: More general capillary pressure and relative permeability models from fractal geometry. J. Contam. Hydrol. 111, 13–24 (2010)CrossRefGoogle Scholar
  22. Liu, H.H., Rutqvist, J.: A new coal-permeability model: internal swelling stress and fracture–matrix interaction. Transp. Porous Med. 82, 157–171 (2010)CrossRefGoogle Scholar
  23. Liu, S., Harpalani, S., Pillalamarry, M.: Laboratory measurement and modeling of coal permeability with continued methane production. Part 2. Modeling results. Fuel 94, 117–124 (2012)CrossRefGoogle Scholar
  24. Nourbakhsh, A.: Determination of capillary pressure, relative permeability and pores size distribution characteristics of coal from Sydney basin-Canada. M.S. thesis, Dalhousie University (2012)Google Scholar
  25. Perera, M.S.A., Ranjith, P.G., Choi, S.K., Airey, D.: The effects of sub-critical and super-critical carbon dioxide adsorption-induced coal matrix swelling on the permeability of naturally fractured black coal. Energy 36, 6442–6450 (2011)CrossRefGoogle Scholar
  26. Puri, R., Evanoff, J.C., Brugler, M.L.: Measurement of coal cleat porosity and relative permeability characteristics. In: SPE Gas Technology Symposium, Society of Petroleum Engineers (1991)Google Scholar
  27. Rapoport, L.A., Laeas, W.J.: Relative permeability to liquid in liquid–gas systems. Trans. AIME 192, 83–89 (1951)Google Scholar
  28. Reznik, A.A., Dabbous, M.K., Fulton, P.F., Taber, J.J.: Air–water relative permeability studies of Pittsburgh and Pocahontas coals. SPE J. 14, 556–562 (1974)CrossRefGoogle Scholar
  29. Schafer, P.S., Schraufnagel, R.A. (eds.): A guide to coalbed methane: the success of coalbed methane. Gas research institute report GRI-94/0397, Chicago (1996)Google Scholar
  30. Shen, J., Qin, Y., Wang, G.X., Fu, X., Wei, C., Lei, B.: Relative permeability of gas and water for different rank coals. Int. J. Coal Geol. 86, 266–275 (2011)CrossRefGoogle Scholar
  31. Shi, J.Q., Durucan, S.: Gas storage and flow in coalbed reservoirs: implementation of a bidisperse pore model for gas diffusion in a coal matrix. SPE Reserv. Eval. Eng. 8, 169–175 (2005)CrossRefGoogle Scholar
  32. Sun, X., Yao, Y., Liu, D., Elsworth, D., Pan, Z.: Interactions and exchange of CO2 and H2O in coals: an investigation by low-field NMR relaxation. Sci. Rep. 6, 19919 (2016)CrossRefGoogle Scholar
  33. SY/T 5843: Gas–water relative permeability measurement. Standardization Administration of Oil and Gas Industry of the People’s Republic of China (1997) (in Chinese)Google Scholar
  34. SY/T 6385: The porosity and permeability measurement of core in net confining stress. Standardization Administration of Oil and Gas Industry of the People’s Republic of China (1999) (in Chinese)Google Scholar
  35. Welge, H.J.: A simplified method for computing oil recovery by gas or water drive. Trans. AIME 195, 99–108 (1952)Google Scholar
  36. Wildenschild, D., Armstrong, R.T., Herring, A.L., Young, I.M., Carey, J.W.: Exploring capillary trapping efficiency as a function of interfacial tension, viscosity, and flow rate. Energy Procedia 4, 4945–4952 (2011)CrossRefGoogle Scholar
  37. Yao, Y., Liu, D.: Comparison of low-field NMR and mercury intrusion porosimetry in characterizing pore size distributions of coals. Fuel 95, 152–158 (2012)CrossRefGoogle Scholar
  38. Yao, Y., Liu, D., Che, Y., Tang, D., Tang, S., Huang, W.: Petrophysical characterization of coals by low-field nuclear magnetic resonance (NMR). Fuel 89, 1371–1380 (2010a)CrossRefGoogle Scholar
  39. Yao, Y., Liu, D., Cai, Y., Li, J.: Advanced characterization of pores and fractures in coals by nuclear magnetic resonance and X-ray computed tomography. Earth Sci. 53, 854–862 (2010b)Google Scholar
  40. Yao, Y., Liu, D., Liu, J., Xie, S.: Assessing the water migration and permeability of large intact bituminous and anthracite coals using NMR relaxation spectrometry. Transp. Porous Med. 107, 527–542 (2015)CrossRefGoogle Scholar
  41. Zhang, H., He, S., Jiao, C., Luan, G., Mo, S., Guo, X.: Determination of dynamic relative permeability in ultra-low permeability sandstones via X-ray CT technique. J. Pet. Explor. Prod. Technol. 4, 443–455 (2014)CrossRefGoogle Scholar
  42. Zhang, J., Feng, Q., Zhang, X., Wen, S., Zhai, Y.: Relative permeability of coal: a review. Transp. Porous Med. 106, 563–594 (2015)CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media B.V., part of Springer Nature 2018

Authors and Affiliations

  1. 1.School of Energy ResourceChina University of GeosciencesBeijingPeople’s Republic of China
  2. 2.Coal Reservoir Laboratory of National Engineering Research Center of CBM Development and UtilizationChina University of GeosciencesBeijingPeople’s Republic of China
  3. 3.Beijing Key Laboratory of Unconventional Natural Gas Geological Evaluation and Development EngineeringChina University of GeosciencesBeijingPeople’s Republic of China
  4. 4.Department of Mining and Minerals EngineeringVirginia Polytechnic Institute and State UniversityBlacksburgUSA

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