Experimental Investigation of Crude-Oil Emulsion Stability: Effect of Oil and Brine Compositions, Asphaltene, Wax, Toluene Insolubles, Temperature, Shear Stress, and Water Cut
- Takaaki Uetani (INPEX Corporation) | Jyunichi Kai (Nippon Kaiji Kentei Kyokai) | Tomoko Hitomi (Nippon Kaiji Kentei Kyokai) | Hitoshi Seino (Nippon Kaiji Kentei Kyokai) | Kiyomasa Shimbori (Nippon Kaiji Kentei Kyokai) | Hideharu Yonebayashi (INPEX Corporation)
- Document ID
- Society of Petroleum Engineers
- SPE Production & Operations
- Publication Date
- May 2020
- Document Type
- Journal Paper
- 320 - 334
- 2020.Society of Petroleum Engineers
- wax, toluene-insoluble, temperature/shear/water, asphaltene, emulsion stability
- 12 in the last 30 days
- 72 since 2007
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An onshore oil well in Japan, referred to as Well M-1 in this paper, experienced a serious emulsion problem soon after the introduction of artificial lift using a hydraulic jet pump. Even though the problem was resolved after switching to a new demulsifier, it is possible that the operator could experience another emulsion problem as the production condition changes in the future and accordingly, the new demulsifier becomes less effective. Therefore, a laboratory case study was conducted to understand not only the cause of the emulsion problem encountered, but also the relative magnitude of several factors affecting emulsion stability. Knowing the conditions that lead to the emulsion problem helps in understanding how to remove the emulsion and in designing intervention treatments to restore long-term well productivity.
At first, the oil and brine samples from Well M-1 were mixed and agitated to form emulsion, and subsequently emulsion stability was evaluated. Subsequently, the mixing conditions were altered to investigate the individual impact on the emulsion stability: (1a) replace Well M-1 oil with another field’s oil, (1b) replace Well M-1 brine with another field’s brine, (2) change concentrations of asphaltene, (3) change concentrations of wax, (4) change concentrations of toluene insolubles, (5) vary temperature between 20 and 70°C, (6) vary shear stress (rotational speed between 3,500 and 15,000 rev/min), and (7) vary water cut between zero and 100%.
The result of the emulsion stability in every test was different. All the above factors showed some impact on emulsion stability, except for brine composition and toluene insolubles, which had little impact on emulsion stability in this study. Operationally speaking, because it was found that the emulsion was stabilized by multiple factors, multiple preventative approaches are required to sustain stable production, free of emulsion.
|File Size||4 MB||Number of Pages||15|
Abdel-Raouf, M. 2012. Factors Affecting the Stability of Crude Oil Emulsions. In Crude Oil Emulsions—Composition Stability and Characterization. Chap. 10. Rijeka, Croatia: Intech.
Al-Sahhaf, T., Elsharkawy, A., and Fahim, M. 2008. Stability of Water-in-Crude Oil Emulsions: Effect of Oil Aromaticity, Resins to Asphaltene Ratio, and pH of Water. Pet Sci Technol 26: 2009–2022. https://doi.org/10.1080/10916460701428904.
ASTM D5186-91, Standard Test Method for Determination of Aromatic Content of Diesel Fuels by Supercritical Fluid Chromatography. 1991. West Conshohocken, Pennsylvania, USA: ASTM International.
ASTM D6560-17, Standard Test Method for Determination of Asphaltenes (Heptane Insolubles) in Crude Petroleum and Petroleum Products. 2017. West Conshohocken, Pennsylvania, USA: ASTM International.
ASTM D893-14, Standard Test Method for Insolubles in Used Lubricating Oils. 2014. West Conshohocken, Pennsylvania, USA: ASTM International.
Davies, G. A., Nilsen, F. P., and Gramme, P. E. 1996. The Formation of Stable Dispersions of Crude Oil and Produced Water: The Influence of Oil Type, Wax and Asphaltene Content. Paper presented at the SPE Annual Technical Conference and Exhibition, Denver, Colorado, USA, 6–9 October. SPE-36587-MS. https://doi.org/10.2118/36587-MS.
Furuichi, N., Uetani, T., Yorozu, H. et al. 2016. Achieving 50% Plus Oil Production in Asphaltene-Stabilized Emulsion Problematic Field Under Artificial Lift Operation. Paper presented at the Abu Dhabi International Petroleum Exhibition and Conference, Abu Dhabi, UAE, 7–10 November. SPE-182979-MS. https://doi.org/10.2118/182979-MS.
Gafonova, O. V. and Yarranton, H. W. 2001. The Stabilization of Water-in-Hydrocarbon Emulsions by Asphaltenes and Resins. J Colloid Interface Sci 241: 469–478. https://doi.org/10.1006/jcis.2001.7731.
Hatzlavramidis, D. T. 1991. Modeling and Design of Jet Pumps. SPE Res Eng 6 (4): 413–419. SPE-19713-PA. https://doi.org/10.2118/19713-PA.
JIS K2249, Crude Petroleum and Petroleum Products—Determination of Density. 2016. Tokyo, Japan: Japanese Industrial Standards Committee.
JIS K2275, Crude Petroleum and Petroleum Products—Determination of Water. 2015. Tokyo, Japan: Japanese Industrial Standards Committee.
JIS K2601, Testing Methods for Crude Petroleum. 2016. Tokyo, Japan: Japanese Industrial Standards Committee.
JIS K2501, Petroleum Products and Lubricants—Determination of Neutralization Number. 2017. Tokyo, Japan: Japanese Industrial Standards Committee.
Kilpatrick, P. 2012. Water-in-Crude Oil Emulsion Stabilization: Review and Unanswered Questions. Energy & Fuels 26 (7): 4017–4026. https://doi.org/10.1021/ef3003262.
Kokal, S. 2006. Crude Oil Emulsions. In Petroleum Engineering Handbook, Vol. 1, Chap. 12. Richardson, Texas, USA: Society of Petroleum Engineers.
Kokal, S. and Al-Juraid, J. 1998. Reducing Emulsion Problems by Controlling Asphaltene Solubility and Precipitation. Paper presented at the SPE Annual Technical Conference and Exhibition, New Orleans, Louisiana, USA, 27–30 September. SPE-48995-MS. https://doi.org/10.2118/48995-MS.
Kokal, S. and Al-Juraid, J. 1999. Quantification of Various Factors Affecting Emulsion Stability: Watercut, Temperature, Shear, Asphaltene Content, Demulsifier Dosage and Mixing Different Crudes. Paper presented at the SPE Annual Technical Conference and Exhibition, Houston, Texas, USA, 3–6 October. SPE-56641-MS. https://doi.org/10.2118/56641-MS.
Petroleum Extension Service. 1990. Treating Oilfield Emulsions, fourth edition. Austin, Texas, USA: The University of Texas at Austin.
PetroWiki. 2019. Stability of Oil Emulsions, https://petrowiki.org/Stability_of_oil_emulsions (accessed 7 June 2019).
Schramm, L. 1992. Emulsions—Fundamentals and Applications in the Petroleum Industry, Vol. 231. Washington, DC, USA: Advances in Chemistry Series, American Chemical Society.
Sjoblom, J., Hemmingsen, P., and Kallevik, H. 2010. Asphaltenes, Heavy Oils, and Petroleomics, Chap. 21. New York, New York, USA: Springer.
Smith, H. and Arnold, K. 1987. Crude Oil Emulsions. In Petroleum Engineering Handbook, Chap. 21. Richardson, Texas, USA: Society of Petroleum Engineers.
Strassner, J. E. 1968. Effect of pH on Interfacial Films and Stability of Crude Oil-Water Emulsions. J Pet Technol 20 (3): 303–312. SPE-1939-PA. https://doi.org/10.2118/1939-PA.
Uetani, T., Furuichi, N., Yorozu, H. et al. 2018. Regaining Oil Production by Overcoming Emulsion Problems After Artificial Lift Installation. SPE Prod & Oper 33 (2): 300–312. SPE-182411-PA. https://doi.org/10.2118/182411-PA.
Walsh, J. M. 2016. The Savvy Separator Series: Part 5. The Effect of Shear on Produced Water Treatment. Oil and Gas Fac 5 (1): 16–23. SPE-0216-0016-OGF. https://doi.org/10.2118/0216-0016-OGF.
Woelflin, W. 1942. The Viscosity of Crude-Oil Emulsions. Paper presented at the Drilling and Production Practice, New York, New York, USA, 1 January. API-42-148.