1887

Abstract

Summary

Al-Shaheen Field, offshore Qatar, is responsible for 45% of Qatar's crude oil production. Kharaib,the most prolific reservoir of Al-Shaheen Field, is an oil wet tight carbonate. Even after an extensive water-flooding for several years, there is substantial amounts of oil left behind owing to the highly oil-wet nature of the reservoir. Wettability altering surfactant offers a very promising EOR technique with ability of releasing the residual oil from tight oil wet pores. Three successful short surfactant injection trials have led to comprehensive planning for conducting a long term surfactant injection pilot to evaluate incremental oil gain.

The pilot planning consists of three-tier approach; additional laboratory experiments, reservoir modelling and field implementation. Laboratory experiments were performed to establish surfactant formulation's stability and adsorption in presence of reservoir fluids and rock. Core floods were performed to estimate incremental recovery with different surfactant slug sizes and concentration. Core flooding results were history matched to obtain necessary parameters for field scale modelling. The candidate location was selected considering reservoir properties, operational constraints and implementation feasibility.

The unique ability of this surfactant is to alter reservoir surface wettability with low adsorption on the rock surface and negligible change in interfacial tension. Core flood experiments showed significant oil recovery and field trials showed injectivity improvements which were indication of the wettability alteration to more water wet state. A long term pilot is planned to establish the surfactant EOR potential in Al-Shaheen reservoirs. Several evaluation options for the success of this pilot such as single well tracer test, inter-well tracer test, micro-pilot tests, time lapse saturation logging, and observation wells have been assessed. Reservoir modelling, logistical considerations, field applicability, drilling schedule and cost implications have been considered for determining the most optimum solution to help de-risk field scale implementation. This paper presents a phased approach to scale up an EOR project in a highly complex offshore carbonate field.

A novel EOR implementation approach called S3IP (Surfactant Induced Improvement in Injectivity and Productivity) is applied which results in incremental recovery and injectivity improvement with single EOR agent. The phased approach taken, from screening the surfactants to short term injectivity trials and then continuing to a long term pilot, is unique for the offshore field and the current oil price condition. This pilot will demonstrate the ability to deliver and inject large quantity of surfactant in challenging offshore environment and to exhibit incremental recovery potential of field scale implementation.

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/content/papers/10.3997/2214-4609.201900069
2019-04-08
2024-04-26
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References

  1. Pal, M, Gilani, S.F., Tarasaulia, G. and Germeia, G.
    Offshore Surfactant Injectivity Trials: From Core to Successful Field Trials in the Al-Shahen Field, 2018, SPE-190373, SPE EOR Conference at OGWA, Muscat, Oman, 26–28th March 2018.
    [Google Scholar]
  2. Abdallah, W., Buckley, J.S., Carnegie, A., Edwards, J., Herold, B., Fordham, E., Graue, A., Habashy, T., Seleznev, N., Signer, C., Hussain, H., Montaron, B., Ziauddin, M.
    2007. Fundamentals of Wettability. Oilfield Review19(2): 44–61.
    [Google Scholar]
  3. Bennetzen, M.V., Mogensen, K., Frank, S. and Mohanty, K.
    2014. January. Dilute Surfactant Flooding Studies in a Low-Permeability Oil-Wet Middle East Carbonate. In IPTC 2014: International Petroleum Technology Conference.
    [Google Scholar]
  4. Acevedo-Velez, C., Mukherjee, J., Yu, W., Mounzer, H., Buckner, W., Falcone-Potts, S., & Hernandez, M.
    2014. Chemical Solutions for Improved Waterflooding in Carbonate Reservoirs. Society of Petroleum Engineers. https://doi.org/10.2118/171954-MS
    [Google Scholar]
  5. Gupta, R., Mohan, K., & Mohanty, K. K.
    2009. Surfactant Screening for Wettability Alteration in Oil-Wet Fractured Carbonates. Society of Petroleum Engineers. https://doi.org/10.2118/124822-MS
    [Google Scholar]
  6. Hirasaki, G., & Zhang, D. L.
    2004. Surface Chemistry of Oil Recovery From Fractured, Oil-Wet, Carbonate Formations. Society of Petroleum Engineers. https://doi.org/10.2118/88365-PA
    [Google Scholar]
  7. Jadhunandan, P.P., Morrow, N.R.
    1991. Spontaneous Imbibition of Water by Crude Oil/Brine/Rock Systems. In Situ15 (4): 319–345.
    [Google Scholar]
  8. Matero, A.
    (2001). Hydrotropes. In Holmberg, K. (Ed.), Handbook of Applied Surface and Colloidal Chemistry (407–420). England: John Wiley & Sons, Ltd.
    [Google Scholar]
  9. Mohan, K., Gupta, R. Mohanty, K.K.
    2011. Wettability Altering Secondary Oil Recovery in Carbonate Rocks. Energy & Fuels25 (9): 3966–3963.
    [Google Scholar]
  10. Morrow, N. R.
    1990. Wettability and Its Effect on Oil Recovery. Journal of Petroleum Technology42 (12): 1476–1484.
    [Google Scholar]
  11. Patil, P. D., Rohilla, N., KatiyarA., Yu, W., FalconeS., NelsonC., RozowskiP.
    2018a. Surfactant based EOR for tight oil reservoirs through wettability alteration: novel surfactant flrmulations and their efficacy to induce spontaneous imbibition. SPE190397-MS
    [Google Scholar]
  12. 2018b. Surfactant based EOR for tight oil unconventional reservoirs through wettability alteration: novel surfactant flrmulations and their efficacy to induce spontaneous imbibition. UDTeC 2896289
    [Google Scholar]
  13. Rohilla, N. and Hirasaki, G.J.
    2011. Pore structure of vuggy carbonates and rate dependent displacement in carbonate rocks. SCA2011-21.
    [Google Scholar]
  14. Rohilla, N., Ravikiran, R., Carlisle, C.T., Jones, N., Davis, M.B. and Finch, K.B.
    2016. Design of a Robust ASP Formulation for Clay Rich and Moderate Permeability Sandstone Reservoir: From Laboratory to Single Well Chemical Tracer Test in the Field. In SPE Improved Oil Recovery Conference. Society of Petroleum Engineers. https://doi.org/10.2118/179678-MS
    [Google Scholar]
  15. Seethepalli, A., Adibhatla, B., Mohanty, K.K.
    2004. Physicochemical Interactions During Surfactant Flooding of Fractured Carbonate Reservoirs. SPE Journal9 (4): 411–418. https://doi.org/10.2118/89423-PA
    [Google Scholar]
  16. Schick, M.J.
    (Ed.). Nonionic Surfactants Physical Chemistry. Marcel Dekker, New York (1987), p.p. 150–157
    [Google Scholar]
  17. Sharma, G., Mohanty, K.
    2013. Wettability Alteration in High-Temperature and High-Salinity Carbonate Reservoirs. SPE Journal18 (4): 646–655. https://doi.org/10.2118/147306-MS
    [Google Scholar]
  18. Sheng, J.J.
    2013. Review of Surfactant Enhanced Oil Recovery in Carbonate Reservoirs. Advances in Petroleum 0Exploration and Development6 (1): 1–10.
    [Google Scholar]
  19. Standness, D.C., Austad, T.
    2000. Wettability Alteration in Chalk 2. Mechanism for Wettability Alteration from Oil-Wet to Water-Wet Using Surfactants. Journal of Petroleum Science and Engineering28, 123–143.
    [Google Scholar]
  20. 2003. Nontoxic Low-cost Amines as Wettability Alteration Chemicals in Carbonates. Journal of Petroleum Science and Engineering39, 431–446.
    [Google Scholar]
  21. 2003. Wettability Alteration in Carbonates: Interaction between Cationic Surfactant and Carboxylates as a Key Factor in Wettability Alteration from Oil-Wet to Water-wet Conditions. Colloids and Surfaces A: Physicochemical and Engineering Aspects216, 243–259.
    [Google Scholar]
  22. Standness, D.C., Nogaret, L.A.D, Chen, H-L., Austad, T.
    2002. An Evaluation of Spontaneous Imbibition of Water into Oil-Wet Carbonate Reservoir Cores Using a Nonionic and a Cationic Surfactant. Energy & Fuels16 (6): 1557–1564.
    [Google Scholar]
  23. Xie, X., Weiss, W.W., Tong, Z., Morrow, N.R.
    2005. Improved Oil Recovery From Carbonate Reservoirs by Chemical Stimulation. SPE Journal10 (3): 276–285. https://doi.org/10.2118/89424-PA
    [Google Scholar]
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