Oil/Water Pipe-Flow Dispersions: From Traditional Flow Loops to Real Industrial-Transport Conditions
- Andrea Shmueli (SINTEF Industry) | Tor Erling Unander (SINTEF Industry) | Heiner Schümann (SINTEF Industry)
- Document ID
- Society of Petroleum Engineers
- SPE Production & Operations
- Publication Date
- February 2019
- Document Type
- Journal Paper
- 260 - 269
- 2019.Society of Petroleum Engineers
- pressure drop, Emulsions, Dispersions, real fluid systems, Subsea processing
- 4 in the last 30 days
- 107 since 2007
- Show more detail
- View rights & permissions
|SPE Member Price:||USD 12.00|
|SPE Non-Member Price:||USD 35.00|
In this paper we present a study on oil/water pipe-flow dispersions. There are two main objectives of this work: The first objective is to gain more knowledge on the behavior of oil/water dispersions in pipe flow; the second objective is to validate a new methodology to characterize dispersion properties at realistic industrial conditions. The characteristics of oil/water flows such as the development of the phase-fraction profiles, droplet-chord lengths, and pressure gradient were studied in a 0.069-m-diameter and 50-m-length horizontal pipe at the Multiphase Flow Laboratory of SINTEF in Norway. The fluid system consisted of a model oil (Exxsol® D80) with and without surfactants, and tap water. A comparison of the experiments with and without a mixing valve was performed. The experiments were conducted at different superficial liquid velocities (Usl) and five different water-cut (WC) values (with WC defined as the ratio of the water superficial velocity to the liquid superficial velocity).
In addition, experiments on a wheel-shaped flow loop were conducted at selected conditions. The wheel mimics realistic pipe-flow conditions for the oil/water dispersions. This methodology allows us to identify flow-developing time scales and long-term behavior, which cannot be studied in a shorter test section. Furthermore, it is possible to have an indication of the viscosity increment when dispersions form.
The results from the pipe-flow experiments show that the effective viscosity of the mixed flow increases by the dispersion formation promoted by the valve. As a result, the pressure gradient in the downstream pipe increases dramatically compared with the same conditions without premixing. For the studied cases, the surfactant concentration did not have any significant effect on the pressure drop in the pipe. However, differences in the phase-fraction profiles were observed, especially with respect to flow development along the pipe. A possible explanation is that the effective viscosity of the created dispersion is not high enough to produce an increase in the pressure drop. Flow development along the pipeline (oil/water separation) is observed only for selected cases without surfactant. For the rest of the experiments, especially with surfactant, the test section was not long enough to observe flow development. With the wheel, it is simple and fast to study both the formation and the stability of dispersions with real fluids at realistic conditions. There are indications that the energy-dissipation rate could be used as a scaling parameter between pipe-flow experiments and the wheel experiments. Wheel experiments can be used cost-efficiently to investigate dispersion characteristics and long-term flow development, which cannot be observed in traditional pipe-flow loops because of their restrictions.
|File Size||1 MB||Number of Pages||10|
Angeli, P. 1996. Liquid-Liquid Dispersed Flows in Horizontal Pipes. PhD thesis, University of London (January 1996).
Boxall, J. A., Koh, C. A., Sloan, E. D. et al. 2010. Measurement and Calibration of Droplet Size Distributions in Water-in-Oil Emulsions by Particle Video Microscope and a Focused Beam Reflectance Method. Industrial & Engineering Chemistry Research 49 (3): 1412–1418. https://doi.org/10.1021/ie901228e.
Elseth, G. 2001. An Experimental Study of Oil/Water Flow in Horizontal Pipes. PhD thesis, Telemark University College, Porsgrunn, Norway (June 2001).
Exxsol is a registered trademark of ExxonMobil Corporation, Irving, Texas.
Kumara, W. A. S., Halvorsen, B. M., and Melaaen, M. C. 2009. Pressure Drop, Flow Pattern and Local Water Volume Fraction Measurements of Oil- Water Flow in Pipes. Measurement Science and Technology 20 (11): 1–18.
Lovick, J. and Angeli, P. 2004. Experimental Studies on the Dual Flow Pattern in Oil-Water Flows. International Journal of Multiphase Flow 30 (2): 139–157. https://doi.org/10.1016/j.ijmultiphaseflow.2003.11.011.
Nädler, M. and Mewes, D. 1997. Flow-Induced Emulsification in the Flow of Two Immiscible Liquids in Horizontal Pipes. International Journal of Multiphase Flow 23 (1): 55–68. https://doi.org/10.1016/S0301-9322(96)00055-9.
Pal, R. and Rhodes, E. 1989. Viscosity/Concentration Relationships for Emulsions. Journal of Rheology 33 (7): 1021–1045. https://doi.org/10.1122/1.550044.
Schümann, H. 2016. Experimental Investigation of Transitional Oil-Water Pipe Flow. PhD thesis, Norwegian University of Science and Technology, Trondheim, Norway.
Schümann, H., Tutkun, M., Yang, Z. et al. 2016a. Experimental Study of Dispersed Oil-Water Flow in a Horizontal Pipe With Enhanced Inlet Mixing, Part 1: Flow Patterns, Phase Distributions, and Pressure Gradients. Journal of Petroleum Science and Engineering 145: 742–752. https://doi.org/10.1016/j.petrol.2016.06.005.
Schümann, H., Chandra, P., and Nydal, O. J. 2016b. Oil-Water Pipe Flow Development After a Valve. Presented at the 9th International Conference on Multiphase Flow, Firenze, Italy, 22–27 May.
Schümann, H. F. M. 2017. The Wheel Flow Loop: A Novel Way to Study Dispersions, ed. SINTEF. Poster presentation given at Tekna: Oil Field Chemistry Symposium, Geilo, Norway, 26–29 March.
Span is a registered trademark of Croda International PLC, Great Britain.
Valle, A. 2000. Three-Phase Gas-Oil-Water Pipe Flow. PhD thesis, Imperial College of Science, Technology, and Medicine, London.
Yang, Z. 2014. A Study of Viscous Oil and Water Pipe Flow. Presented at the 9th North American Conference on Multiphase Technology, Banff, Canada, 11–13 June. BHR-2014-E1.