A new methodology is presented to simulate WAG injection scenarios. In addition to properly model three-phase flow, the concept of directional and cyclic hysteresis is modelled to capture the underlying physics. Laboratory measured data is used to validate the proposed methodology.

The approach in this paper is based on updating parameters of WAG hysteresis model during the course of cyclic injection to adequately model the key physical mechanisms in WAG injection tests. For this study, we used ‘Modified Stone 1’ model for calculating three-phase relative permeability (kr) data from measured two-phase kr. We used Land’s parameter (C) and the reduction exponent (alpha) for gas secondary drainage relative permeability as the variable parameters in WAG hysteresis model for matching the coreflood production and pressure data.

Results of this study showed that, by applying the proposed methodology for simulating WAG coreflood experiments at different wettability conditions, better match to the experimental data can be achieved. In this paper, we highlight the shortcomings of the current capability of numerical simulators for simulating WAG injection. Some areas of improvement to the current WAG hysteresis model is introduced and a new methodology is proposed to improve the performance of current simulation procedures for WAG injection scenarios.


Article metrics loading...

Loading full text...

Full text loading...


  1. British Petroleum
    , 2016. BP energy outlook 2016. British Petroleum, 53(9), p. 98.
    [Google Scholar]
  2. Kelkar, M.
    , 2011. Increasing Recovery Factors: A Necessity. President Alain Labastie, 2(1).
    [Google Scholar]
  3. Blunt, M.
    1999, An Empirical Model for Three-Phase Relative Permeability. SPE Annual Technical Conference and Exhibition (1999).
    [Google Scholar]
  4. Shahrokhi, O., Fatemi, M. & Sohrabi, M.
    , 2014. Assessment of Three Phase Relative Permeability and Hysteresis Models for Simulation of Water-Alternating-Gas (WAG) Injection in Water-wet and Mixed-wet Systems. SPE Improved Oil Recovery Symposium, p.1–20.
    [Google Scholar]
  5. Fatemi, M., Shahrokhi, O. & Sohrabi, M.
    , 2015. Experimental Investigation of Oil Recovery from Carbonate Reservoir Rocks Under Oil-Wet Condition: Waterflood, Gas Injection, SWAG and WAG injections. The Abu Dhabi International Petroleum Exhibition and Conference (2015)
    [Google Scholar]
  6. API
    , 2005. Summary of Carbon Dioxide Enhanced Oil Recovery (CO2 EOR). API.
    [Google Scholar]
  7. Christensen, J.R., Larsen, M. & Nicolaisen, H.
    , 2000. Compositional Simulation of Water-Alternating-Gas Processes. SPE Annual Technical Conference and Exhibition (2000).
    [Google Scholar]
  8. Stone, H.L.
    , 1970. Probability Model for Estimating Three-Phase Relative Permeability. J. Pet Tech, 22, p.214–218. SPE-2116-PA.
    [Google Scholar]
  9. Hustad, O. S. and Holt, T.
    “Gravity Stable Displacement of Oil by Hydrocarbon Gas After Waterflooding,” paper SPE 24116, presented at the SPE/DOE Eighth Symposium on Enhanced Oil Recovery, Tulsa, Oklahoma, USA (April 22–24 1992).
    [Google Scholar]
  10. Element, D.J. et al.
    , 2003. Assessment of Three-Phase Relative Permeability Models Using Laboratory Hysteresis Data. Proceedings - SPE International Improved Oil Recovery Conference in Asia Pacific, p.403–410.
    [Google Scholar]
  11. Sohrabi, M., Tehrani, D.H. & Al-Abri, M.
    (2007). Performance of Near-Miscible Gas and SWAG Injection in a Mixed-Wet Core. Paper presented at the International Symposium of the Society of Core Analysts, Calgary, Canada.
    [Google Scholar]
  12. Sohrabi, M., & Fatemi, S. M.
    (2012). Experimental Investigation of Oil Recovery by Different Injection Scenarios under Low Oil/Gas IFT and Mixed-Wet Condition: Water-Flood, Gas Injection, WAG and SWAG Injection.
    [Google Scholar]
  13. Jahanbakhsh, A. et al.
    , 2016. A Comparative Study of the Effect of Gas/Oil IFT Variation on Two- and Three-Phase Relative permeability and the Performance of WAG Injection at Laboratory Scale. SPE Improved Oil Recovery Conference, (2016).
    [Google Scholar]
  14. Shahverdi, H., Sohrabi, M. & Fatemi, S.M.
    , 2013. Relative Permeability Characterization for Water-Alternating-Gas (WAG) Injection in Oil Reservoirs. SPE Offshore Europe Oil and Gas Conference and Exhibition, (2005), p.1–10.
    [Google Scholar]
  15. Mahzari, P., and Sohrabi, M.
    , 2016. SPE-183321-MS. An Improved Approach for Estimation of Flow and Hysteresis Parameters Applicable to WAG Experiments. , (i), p.1–20.
    [Google Scholar]

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error