Droplet shear in oil/water emulsion produced by centrifugal pump and gear pump

Droplet shear in oil/water emulsion produced by centrifugal pump and gear pump

Hussain H. Al-Kayiem Jaseer E. Hamza Sundus S. Al-Azawiey

Mechanical Engineering Department, Universiti Teknologi PETRONAS, Perak, Malaysia

Department of Electro-Mechanics, University of Technology, Baghdad, Iraq

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Before being fed into the separators, a pump is often used to maintain adequate flowing pressure of oil/ water emulsion in a production conduit, especially in a depleted or matured reservoir. Droplet shearing and size reduction due to the pump highly affect the separation performance. This paper aims to present an experimental investigation on the shearing of oil droplets in an oil/water production fluid passing through a high rpm single-stage centrifugal pump (C-pump) and a lower rpm gear pump. A cross polarizer microscope has achieved sample analyses. The experiments have been carried out at various water/oil ratios, from 70/30 to 90/10, with two different temperatures of 50 oC and 80 oC. Further, the viscosities of the fluid sample from both pump outlets are correlated with the water cuts. The results are presented in a graphical format showing the droplet size distributions of different cases from the two tested pump types. There is a general trend of higher shear intensity and smaller mean oil droplets with the C-pump than the gear pump. Water cut and the temperature seem to have a small effect on the shear- ing of the droplets. Further, the viscosity correlation for the fluid collected from two pump outlets at different temperatures and water cuts shows a slight decrease in viscosity with the shear rate. However, it is highly affected by the water cut and temperature.


Droplet shear, emulsion, oil/water separation, produced water, water cut, water/oil emulsion


[1] Shi, S. Y. & Xu, J. Y., Flow field of continuous phase in a vane-type pipe oil–water separator. Experimental Thermal and Fluid Science, 60, pp. 208–212, 2015. https://doi.org/10.1016/j.expthermflusci.2014.09.011

[2] Liu, C., Li, M., Han, R., Li, J. & Liu, C., Rheology of water-in-oil emulsions with different drop sizes. Journal of Dispersion Science and Technology, 37(3), pp. 333–344, 2016. https://doi.org/10.1080/01932691.2015.1010729

[3] Van Campen, L., Mudde, R.F., Slot, J. & Hoeijmakers, H., A numerical and experimental survey of a liquid-liquid axial cyclone. International Journal of Chemical Reactor Engineering, 10(1), 2012. https://doi.org/10.1515/1542-6580.3003

[4] Delfos, R., Murphya, S., Stanbridge, D., Oluji, Z. & Jansen, P. J., A design tool for optimizing axial liquid–liquid hydrocyclones. Minerals Engineering, 17(5), pp. 721–731, 2004. https://doi.org/10.1016/j.mineng.2004.01.012

[5] Kitoh, O., Experimental study of turbulent swirling flow in a straight pipe. Journal of Fluid Mechanics, 225, pp. 445–479, 1991. https://doi.org/10.1017/S0022112091002124

[6] Dohnal, M. & Hájek, J., Computational analysis of swirling pipe flow. Chemical Engineering Transaction, 52, pp. 757–762, 2016. https://doi.org/10.3303/CET1652127

[7] Husveg, T., Operational control of deoiling hydrocyclones and cyclones for petroleum flow control: Trygve Husveg, University of Stavanger, 2007. https://books.google.com.my/books?id=YD%5C_sOwAACAAJ

[8] Dirkzwager, M., A new axial cyclone design for fluid-fluid separation, TU Delft, Delft University of Technology, 1996.

[9] Dalmazzone, C., Génération mécanique des émulsions. Oil & Gas Science and Technology, 55(3), pp. 281–305, 2000. https://doi.org/10.2516/OGST:2000020

[10] Vikan, A. M. H., A study of the effect of pumps and desanding cyclones on oil droplets in produced water, University of Stavanger, Norway, 2011. http://hdl.handle.net/11250/182495

[11] Arnold, K. & Stewart, M. I., eds., Surface Production Operations - Design of Oil Handling Systems and Facilities, 2nd ed., Gulf Professional Publishing, 2008. https://doi.org/10.1016/B978-088415821-9/50001-4

[12] Flanigan, D. A., Stolhand, J. E., Shimoda, E. & Skilbeck, F., Use of low-shear pumps and hydrocyclones for improved performance in the clean-up of low-pressure water. SPE Production Engineering, 7(3), pp. 295–300. 1992. https://doi.org/10.2118/19743-PA

[13] Nocente, A., Separation Friendly Produced Water Pumps, Doctoral thesis, NTNU, 263, 2016. http://hdl.handle.net/11250/2414453

[14] Svarovsky, L. & Thew, M., Hydrocyclones: Analysis and Applications, Springer Science & Business Media, 1992. https://books.google.com.my/books?id=dK%5C_qpSA-74IC

[15] AlShammari, A., Centrifugal Pump Shear Effects on Oil Continuous and Water Continuous Dispersed Flow, University of Tulsa, 2013. https://books.google.com.my/books?id=x9MIngEACAJ

[16] Walsh, J. M., The Savvy Separator Series: Part 5. The effect of shear on produced water treatment. Oil and Gas Facilities, 5(1), pp. 16–23, 2016. https://doi.org/10.2118/0216-0016-OGF

[17] Zhang, M., Wang, S., Mohan, R.S., Shoham, O. & Gao, H., Shear effects of gear pump on oil-water flow. SPE Latin American and Caribbean Petroleum Engineering Conference, Quito, Ecuador, November 2015. https://doi.org/10.2118/177206-MS

[18] Farah, M. A., Oliveira, R. C., Caldas, J. N., & Rajagopal, K., Viscosity of water-in-oil emulsions: Variation with temperature and water volume fraction. Journal of Petroleum Science and Engineering, 48(3–4), pp. 169–184, 2005. https://doi.org/10.1016/j.petrol.2005.06.014

[19] Zhang, M., Dabirian, R., Mohan, R. S., & Shoham, O., Effect of shear and water cut on phase inversion and droplet size distribution in oil–water flow. ASME, Journal of Energy Resources Technology, 141(3), p. 032905, 2019. https://doi.org/10.1115/1.4041661

[20] Van der Zande, M. J. & van den Broek, W., Break- up of oil droplets in the production system. Proc. ASME, Sources of Energy Technology Conference and Exhibition, Houston, 2–4 February, ETCE98-4744. 1998.

[21] Jiang, M. & Zhao, L., Pressure and separation performance of oil/water hydrocyclones. Production and Operations Symposium, Society of Petroleum Engineers, January 2007. https://doi.org/10.2118/106547-M

[22] Shad, S., Salarieh, M., Maini, B. & Gates, I. D., The velocity and shape of convected elongated liquid drops in narrow gaps. Journal of Petroleum Science and Engineering, 72(1–2), pp. 67–77, 2010. : https://doi.org/10.1016/j.petrol.2010.03.005

[23] Meldrum, N., Hydrocyclones: A solution to produced water treatment. SPE Production & Operations, 3(4), pp. 669–676, 1988. https://doi.org/10.2118/16642-PA

[24] Braginsky, L. M. & Belevitskaya, M. A., Kinetics of droplets breakup in agitated vessels. Liquid–Liquid Systems, ed. N.N. Krilov, Nova Science, Commack, New York, 1996.

[25] Anisa, A. I. & Nour, A. H., Effect of viscosity and droplet diameter on water-in-oil (w/o) emulsions: An experimental study. Journal of World Academy of Science Engineering and Technology, 38, pp. 692, 694, 2010.

[26] Floury, J., Desrumaux, A. & Lardieres, J., Effect of high-pressure homogenization on droplet size distributions and rheological properties of model oil-in-water emulsions. Innovative Food Science & Emerging Technologies, 1(2), pp. 127–134. 2000. https://doi.org/10.1016/S1466-8564(00)00012-6

[27] McClements, D., Emulsions: Principles, Practice and Techniques, CRC Press, Boca Raton, 2005. https://doi.org/10.1201/9781420039436

[28] Traynor, M., Burke, R., Frias, J.M., Gaston, E. & Barry-Ryan, C., Formation and stability of an oil in water emulsion containing lecithin, xanthan gum and sunflower oil. International Food Research Journal, 20(5), pp. 2173–2181, 2013.

[29] Tcholakova, S., Denkov, D., Ivanov, I. & Campbell, B., Coalescence stability of emulsions containing globular milk proteins. Advances in Colloid and Interface Science, 123–126, pp. 259–293, 2006. https://doi.org/10.1016/j.cis.2006.05.021

[30] Dłużewska, E., Stobiecka, A. & Maszewska, M., Effect of oil phase concentration on rheological. Acta Science Poland Technology Alimentarius, 5, pp. 147–156. 2006.