Investigation of Droplet Size Produced in Two-Phase Gravity Separators

Authors: Kul Pun, F. A. Hamad, T. Ahmed, J. O. Ugwu, J. Eyers, G. Lawson, P. A. Russell

Abstract:

Determining droplet size and distribution is essential when determining the separation efficiency of a two/three-phase separator. This paper investigates the effect of liquid flow and oil pad thickness on the droplet size at the lab scale. The findings show that increasing the inlet flow rates of the oil and water results in size reduction of the droplets and increasing the thickness of the oil pad increases the size of the droplets. The data were fitted with a simple Gaussian model, and the parameters of mean, standard deviation, and amplitude were determined. Trends have been obtained for the fitted parameters as a function of the Reynolds number, which suggest a way forward to better predict the starting parameters for population models when simulating separation using CFD packages. The key parameter to predict to fix the position of the Gaussian distribution was found to be the mean droplet size.

Keywords: Two-phase separator, average bubble droplet, bubble size distribution, liquid-liquid phase.

References:

[1] Asselt, H. van (2021) Breaking a Taboo: Fossil Fuels at COP26, Breaking a Taboo: Fossil Fuels at COP26 – EJIL: Talk! www.ejiltalk.org. Available at: https://www.ejiltalk.org/breaking-a-taboo-fossil-fuels-at-cop26/ (Accessed: April 5, 2022)
[2] Short-Term Energy Outlook. (2022) Washington, D.C: Energy Information Administration, Office of Energy Markets and End Use, U.S. Dept. of Energy. Available at: https://www.eia.gov/outlooks/steo/report/global_oil.php (Accessed: April 6, 2022)
[3] Wood, L. (2018) Global Three-phase Separator Market in the Oil and Gas Industry 2018-2022 - ResearchAndMarkets.com Available at: https://www.businesswire.com/news/home/20180807005429/en/Global-Three-phase-Separator-Market-in-the-Oil-and-Gas-Industry-2018-2022-ResearchAndMarkets.com (Accessed: April 5, 2022).
[4] Ahmed, T. G. (2021) Optimisation of three-phase separator design through computational fluid dynamics simulation and experimental investigation. Teesside University.
[5] Monnery, W. and Svrcek, W. (1994) 'Successfully Specify Three-Phase Separators', Chemical Engineering Progress, 90(9), pp. 29–40
[6] Stewart, M. and Arnold, K.E (2008). Surface Production Operations. Volume 1, Design of Oil Handling Systems and Facilities.
[7] Yeoh, G. H. and Tu, J. (2014) Multiphase Flow Analysis Using Population Balance Modeling, Multiphase Flow Analysis Using Population Balance Modeling. doi: 10.1016/c2011-0-05568-0.
[8] Ahmed, T., Hamad, F. and Russell, P. A. (2017) 'The use of CFD simulations to compare and evaluate different sizing algorithms for three-phase separators', OTC Brasil 2017, pp. 1051–1066. DOI: 10.4043/28066-ms.
[9] Kharoua, N., Khezzar, L. and Saadawi, H. (2012) 'Using CFD to model the performance of retrofit production separators in Abu Dhabi', Society of Petroleum Engineers - Abu Dhabi International Petroleum Exhibition and Conference 2012, ADIPEC 2012 - Sustainable Energy Growth: People, Responsibility, and Innovation, 3, pp. 1776-1784. doi: 10.2118/161521-ms.
[10] Wright, c. c. & Douglas, D. w., 1966. The disposal of APA oil field wastewater. American petroleum institute
[11] Hopper, w. b. & jacobs, l., 1996. Handbook of Separation Techniques for Chemical Engineers. 3 ed. s.l.:s.n.
[12] Pourahmadi Laleh, A., 2010. CFD simulation of multiphase separators, Calgary: University of Calgary-doctoral thesis.
[13] Walas, M. & Stanley, 1990. Chemical Process, Equipment Selection and Design. USA: USA inc.
[14] Oshinowo, L. M. and Vilagines, R. D. (2020) 'Modeling of oil-water separation efficiency in three-phase separators: Effect of emulsion rheology and droplet size distribution', Chemical Engineering Research and Design, 159, pp. 278–290. DOI: 10.1016/j.cherd.2020.02.022
[15] Song, J. H. et al. (2010) 'Three-phases separator sizing using drop size distribution', Proceedings of the Annual Offshore Technology Conference, 2(May), pp. 1011–1023. DOI: 10.4043/20558-ms.
[16] Zhai, L. S. et al. (2017) 'Measurement of droplet sizes in bubbly oil-in-water flows using a fluid-sampling device', Measurement: Journal of the International Measurement Confederation, 102, pp. 296–308. doi: 10.1016/j.measurement.2017.01.055.
[17] Rishi Kumari and Narinder Rana (2015) 'Particle Size and Shape Analysis using ImageJ with Customised Tools for Segmentation of Particles', International Journal of Engineering Research and, V4(11), pp. 247–250. DOI: 10.17577/ijertv4is110211.
[18] Laupsien, D., Le Men, C., Cockx, A. and Liné, A., 2019. Image processing for bubble morphology characteristics in diluted bubble swarms. Physics of Fluids, 31(5), p.053306.doi: 10.1063/1.5088945
[19] Liang, Y., Zhao, S., Jiang, X., Jia, X. & Li, W. 2013, "Numerical simulation on flow field of oilfield three-phase separator", Journal of Applied Mathematics, vol. 2013.
[20] Wilson, D.A., Pun, K., Ganesan, P.B. and Hamad, F. (2021b) 'Geometrical optimisation of a venturi-type microbubble generator using CFD simulation and experimental measurements', Designs, 5(1), pp. 1-18. doi: 10.3390/designs5010004
[21] Lappalainen, T. and Lehmonen, J. (2012) 'Determinations of bubble size distribution of foam-fibre mixture using circular hough transform', Nordic Pulp and Paper Research Journal, 27(5), pp. 930–939. doi: 10.3183/NPPRJ-2012-27-05-p930-939
[22] Guo, F., Yang, Y., Chen, B. and Guo, L. (2010) 'A novel multi-scale edge detection technique based on wavelet analysis with application in multiphase flows', Powder Technology, 202(1-3), pp. 171-177