1887

Abstract

Summary

In the West Salym field, a mature waterflood is ongoing with increasing water cuts and declining oil production. To counter the decline a tertiary oil recovery technique called Alkaline-Surfactant-Polymer (ASP) flooding was selected. According to earlier studies the potential incremental oil recovery factor due to ASP injection is 15–20% of the ASP-targeted field STOIIP. An injection/production pilot to demonstrate the oil recovery potential of ASP technology and to obtain information for decisions on the subsequent commercial ASP projects was started in February 2016. ASP injection started in July 2016. The pilot area was developed with a 5-spot well pattern: 4 injectors connect to a single producer through the 15–20 m thick sandstone formation with permeabilities varying from 10 to 100 mD. Because of the short inter-well distance matrix conditions were required for the injection. This requirement in combination with the relatively low permeability of the reservoir rock resulted in the recognition that loss of injectivity is a major risk for the project.

This paper focuses on de-risking polymer injectivity for both the ASP and polymer chase injection. We discuss the selection of the polymer type, molecular weight and concentration, specification of the water quality and chemical preparation procedures that are all important to minimize the risk of injectivity decline. Additional experimental work that was performed to qualify filtration of the polymer solution using a very small filter sizes is described. During long term injection experiments in both representative outcrop and reservoir material continuous pressure increase indicating permeability loss was initially observed. In investigating possible causes and feasible mitigations for the loss of injectivity different scenarios were tested. Both pre-shearing the polymer, pre-filtering the solution and different ways of preparing were tried and resulted in better results. A step change was made when dissolving the polymer in higher pH solution resulting in filtration ratios close to 1 and good injectivity in representative core material. Furthermore, in close collaboration with the polymer vendor, ways were found to improve the polymer quality in the manufacturing process in order to meet our strict specifications. Finally the laboratory results and field observations during ASP and subsequent polymer chase injection will be presented.

The results of this work could be used to define the polymer specifications for ASP and polymer flooding in the reservoir with permeability range (from 10 to 100 mD) that is considered at the border of the typical screening criteria for the polymer application. Due to large amount of such reservoirs a successful mitigation for polymer injectivity could have significant impact on the application of polymer flood in the oil industry.

Loading

Article metrics loading...

/content/papers/10.3997/2214-4609.201700241
2017-04-24
2024-04-24
Loading full text...

Full text loading...

References

  1. API-RP-63
    [1990] Recommended practices for evaluation of polymers used in enhanced oil recovery. American Petroleum Institute.
    [Google Scholar]
  2. Barnes, J.R. van Batenburg, D.W. Faber, M.J. van Rijn, C.H.T. Geib, S. van Kuijk, S.R.
    [2015] Quality assurance and controls of surfactants for field scale EOR pilot projects. Paper SPE177613 presented at the Abu Dhabi International Petroleum Exhibition and Conference, Abu Dhabi, UAE, 9–12 November.
    [Google Scholar]
  3. Barnes, J.R. Perez Regalado, D. Doll, M.J. King, T.E. Pretzer, L.E. Semple, T.C.
    [2016] Essentials of upscaling surfactants for EOR field projects. Paper SPE179573 presented at the SPE Improved Oil Recovery Conference, Tulsa, Oklahoma, USA, 11–13 April.
    [Google Scholar]
  4. Buijse, M.A. Prelicz, R.M. Barnes, J.R. Cosmo, C.
    [2010] Application of internal olefin sulfonates and other surfactants to EOR. Part 2: The design and execution of an ASP field test. Paper SPE129769 presented at the SPE Improved Oil Recovery Symposium, Tulsa, Oklahoma, USA, 24–28 April.
    [Google Scholar]
  5. Chapman, E.J. Mercer, D. Jerauld, G. Shields, R. Sorbie, K. Mogford, D. Cable, A.
    [2015] Polymer flooding for EOR in the Schiehallion field – Porous flow rheological studies of high molecular weight polymers. Paper presented at the 18th European Symposium on Improved Oil Recovery, Dresden, Germany, 14–16 April.
    [Google Scholar]
  6. Dann, M.W. Burnett, D.B. Hall, L.M.
    [1982] Polymer performance in low permeability reservoirs. Paper SPE10615 presented at the SPE 6th International Symposium on Oilfield and Geothermal Chemistry, Dallas, Texas, USA, 25–27 January.
    [Google Scholar]
  7. Dwarakanath, V. Dean, R.M. Slaughter, W. Alexis, D. Espinosa, D. Kim, D.H. Lee, V. Malik, T. Winslow, G. Jackson, A.C. Thach, S.
    [2016] Permeability reduction due to use of liquid polymers and development of remediation options. Paper SPE179657 presented at the SPE Improved Oil Recovery Conference, Tulsa, Oklahoma, USA, 11–13 April.
    [Google Scholar]
  8. Farajzadeh, R. Lotfollahi, M. Bedrikovetsky, P.
    [2015] Simultaneous sorption and mechanical entrapment during polymer flow through porous media. Paper SPE175380 presented at the SPE Kuwait Oil & Gas Show and Conference, Mishref, Kuwait, 11–14 October.
    [Google Scholar]
  9. Glasbergen, G. Karpan, V.M. Shuster, M.M. Wever, D.
    [2016] Polymer-containing oil recovery formulation. Shell Internationale Research Maatschappij B.V., WO2016/139302 A1.
    [Google Scholar]
  10. Glasbergen, G. Wever, D. Keijzer, E. Farajzadeh, R.
    [2015] Injectivity loss in polymer floods: causes, preventions and mitigations. Paper SPE175383 presented at the SPE Kuwait Oil & Gas Show and Conference, Mishref, Kuwait, 11–14 October.
    [Google Scholar]
  11. Hall, H.N.
    [1963] How to analyze waterflood injection well performance. World Oil, 128–130.
    [Google Scholar]
  12. Handa, R. Yoshida, N. Hosoda, J. Furuno, A.
    [1980] Modification of acrylamide polymers. Nitto chemical industry, US 4,313,863.
    [Google Scholar]
  13. Hirasaki, G.J. Pope, G.A.
    [1974] Analysis of factors influencing mobility and adsorption in the flow of polymer solution through porous media. SPE Journal, 14, 337–346.
    [Google Scholar]
  14. Jouenne, S. Klimenko, A. Levitt, D.
    [2016] Tradeoffs between emulsion and powder polymers for EOR. Paper SPE179631 presented at the SPE Improved Oil Recovery Conference, Tulsa, Oklahoma, USA, 11–13 April.
    [Google Scholar]
  15. Karpan, V.M. Volokitin, Y.I. Shuster, M.Y. Tigchelaar, W. Chmuzh, I.V. Koltsov, I.N. Tkachev, I.V. van Batenburg, D.W. Faber, M.J. Skripkin, A.
    [2014] West Salym ASP pilot: Project front-end engineering. Paper SPE169157 presented at the SPE Improved Oil Recovery Symposium, Tulsa, Oklahoma, USA, 12–16 April.
    [Google Scholar]
  16. Levitt, D.B.
    [2009] The optimal use of enhanced oil recovery polymers under hostile conditions. PhD dissertation.
    [Google Scholar]
  17. Lotfollahi, M. Farajzadeh, R. Delshad, M. Al-Abri, K. Wassing, B.M. Mjeni, R. Awan, K. Bedrikovetsky, P.
    [2015] Mechanistic simulation of polymer injectivity in field tests. Paper SPE174665 presented at the SPE Enhanced Oil Recovery Conference, Kuala Lumpur, Malaysia, 11–13 August.
    [Google Scholar]
  18. Niall, M. O’Connor, D.
    [1969] Polyacrylamide gels containing latent thermal degradation inhibitor. American Cyanamid Company, US 3,622,533.
    [Google Scholar]
  19. Southwick, J.G. Karpan, V.M. van den Pol, E. Shuster, M.M. Glasbergen, G. van Rijn, C.H.T. Wever, D. Li, L.
    [2016] Polymer-containing oil recovery formulation. Shell Internationale Research Maatschappij B.V., WO2016/139298 A1.
    [Google Scholar]
  20. Ottani, H. Furuno, A. Ohshima, I.
    [1977] Method for reducing the adhesiveness of hydrogel-like polymer by adding polyethylene glycol. Nitto chemical industry, US 4,134,871.
    [Google Scholar]
  21. Teletzke, G.F. Wattenbarger, R.C. Wilkinson, J.R.
    [2010] Enhanced oil recovery pilot testing best practices. SPE Reservoir Evaluation & Engineering, 13, 143–154.
    [Google Scholar]
  22. Thomas, A.
    [2016] Polymer Flooding. In: Zeron, L.R. (Ed.) Chemical Enhanced Oil Recovery (CEOR), a Practical Overview. 55–100.
    [Google Scholar]
  23. Thomas, A. Gaillard, N. Favero, C.
    [2013] Some key features to consider when studying acrylamide-based polymers for chemical enhanced oil recovery. Oil & Gas Science and Technology - Rev. IFP Energies nouvelles, 67(6), 887–902.
    [Google Scholar]
  24. Van der Heyden, F.H.J. Mikhaylenko, E. de Reus, A.J. van Batenburg, D.W. Karpan, V.M. Volokitin, Y.
    [2017] Injectivity experiences and its surveillance in the West Salym ASP pilot. Paper Th B07 presented at the 19th European Symposium on Improved Oil Recovery, Stavanger, Norway, 24–27 April.
    [Google Scholar]
http://instance.metastore.ingenta.com/content/papers/10.3997/2214-4609.201700241
Loading
/content/papers/10.3997/2214-4609.201700241
Loading

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