A New Comprehensive Model for Predicting Liquid Loading in Gas Wells
- Shu Luo (University of Tulsa) | Mohan Kelkar (University of Tulsa) | Eduardo Pereyra (University of Tulsa) | Cem Sarica (University of Tulsa)
- Document ID
- Society of Petroleum Engineers
- SPE Production & Operations
- Publication Date
- November 2014
- Document Type
- Journal Paper
- 337 - 349
- 2014.Society of Petroleum Engineers
- liquid loading, film thickness, deviated well, gas well
- 5 in the last 30 days
- 896 since 2007
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Liquid loading, which can lead to rapid gas-rate decline and can even cease gas production, is a common phenomenon found in most mature gas wells. An accurate prediction of the inception of liquid loading is of great interest to operators, for the reason that remedial measures can be applied in a timely manner to prevent such conditions from being realized, thereby extending the production life of a gas well. However, the mechanism that is responsible for liquid loading still remains controversial. In the literature, at least three different definitions of liquid loading exist. The first definition is based on the intersection of inflow and outflow curves, the second definition is based on the reversal of entrained liquid droplets, and the third definition is based on the reversal of liquid film. These definitions yield different results when predicting the inception of liquid loading. In this paper, a new definition of liquid loading is introduced. This new definition is based on the relative contributions of gravity and residual pressure drop, and it is validated by its agreement with air/water experimental data. A new comprehensive model is developed that is based on the Barnea (1986, 1987) model. For vertical wells, the new model can better predict the inception of liquid loading than the widely used Turner et al. (1969) equation. For deviated wells, it is observed in the field and in laboratories that liquid loading starts much earlier than in vertical wells, and most liquid-loading equations are not appropriate for deviated wells. The new model takes into account the nonuniform film thickness around the circumferential position of the pipe, and, thus, it improves the prediction of liquid loading in deviated wells. The new model is validated through the use of field data in the literature and experimental data obtained at the University of Tulsa. In addition to the literature data, a new set of field data is reported and used to validate the new model, which shows a significant improvement over the droplet model as well as other film models.
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Andritsos, N. and Hanratty, T.J. 1987. Influence of interfacial waves in stratified gas-liquid flows. AIChE J. 33 (3): 444–454. http://dx.doi.org/10.1002/aic.690330310.
Alamu, M.B. 2012. Gas-Well Liquid Loading Probed With Advanced Instrumentation. SPE J. 17 (1): 251 - 270. SPE-153724-PA. http://dx.doi.org/10.2118/153724-PA.
Barnea, D. 1986. Transition from annular flow and from dispersed bubble flow—unified models for the whole range of pipe inclinations. Int. J. Multiphase Flow 12 (5): 733-744. http://dx.doi.org/10.1016/0301-9322(86)90048-0.
Barnea, D. 1987. A unified model for predicting flow-pattern transitions for the whole range of pipe inclinations. Int. J. Multiphase Flow 13 (1): 1-12. http://dx.doi.org/10.1016/0301-9322(87)90002-4.
Belfroid, S.P.C., Schiferli, W., Alberts, G.J.N. et al. 2008. Prediction Onset and Dynamic Behaviour of Liquid Loading Gas Wells. Presented at the SPE Annual Technical Conference and Exhibition, Denver, 21–24 September. SPE-115567-MS. http://dx.doi.org/10.2118/115567-MS.
Chupin, G., Hu, B., Haugset, T. et al. 2007. Integrated Wellbore/Reservoir Model Predicts Flow Transients in Liquid-Loaded Gas Wells. Presented at the SPE Annual Technical Conference and Exhibition, Anaheim, California, USA, 11-14 November. SPE-110461-MS. http://dx.doi.org/10.2118/110461-MS.
Coleman, S.B., Clay, H.B., McCurdy, D.G. et al. 1991a. A New look at predicting gas-well load-up. J Pet Technol 43 (3): 329-333. SPE-20280-PA. http://dx.doi.org/10.2118/20280-PA.
Coleman, S.B., Clay, H.B., McCurdy, D.G. et al. 1991b. Understanding gas-well load-up behavior. J Pet Technol 43 (3): 334-338. SPE-20281-PA. http://dx.doi.org/10.2118/20281-PA.
Dousi, N., Veeken, C., and Currie, P.K. 2006. Numerical and Analytical Modelling of the Gas Well Liquid Loading Process. SPE Prod & Oper 21 (4): 475-482. SPE-95282-PA. http://dx.doi.org/10.2118/95282-PA.
Duggan, J. 1961. Estimating Flow Rates Required To Keep Gas Wells Unloaded. J Pet Technol 13 (12): 1173-1176. SPE-32-PA. http://dx.doi.org/10.2118/32-PA.
Fore, L.B., Beus, S.G., and Bauer, R.C. 2000. Interfacial friction in gas–liquid annular flow: analogies to full and transition roughness. Int. J. Multiphase Flow 26 (11): 1755-1769. http://dx.doi.org/10.1016/S0301-9322(99)00114-7.
Geraci, G., Azzopardi, B.J., and van Maanen, H.R.E. 2007. Effect of inclination on circumferential film thickness variation in annular gas/liquid flow. Chem. Eng. Sci. 62 (11): 3032-3042. http://dx.doi.org/10.1016/j.ces.2007.02.044.
Guo, B., Ghalambor, A., and Xu, C. 2006. A Systematic Approach to Predicting Liquid Loading in Gas Wells. SPE Prod & Oper 21 (1): 81 - 88. SPE-94081-PA. http://dx.doi.org/10.2118/94081-PA.
Henstock, W.H. and Hanratty, T.J. 1976. The interfacial drag and the height of the wall layer in annular flows. AIChE J. 22 (6): 990-1000. http://dx.doi.org/10.1002/aic.690220607.
Hewitt, G.F., Jayanti, S., and Hope, C.B. 1990. Structure of thin liquid films in gas-liquid horizontal flow. Int. J. Multiphase Flow 16 (6): 951-957. http://dx.doi.org/10.1016/0301-9322(90)90100-W.
Paz, R.J. and Shoham, O. 1999. Film-Thickness Distribution for Annular Flow in Directional Wells: Horizontal to Vertical. SPE J. 4 (2): 83 - 91. SPE-56233-PA. http://dx.doi.org/10.2118/56233-PA.
Sarica, C., Yuan, G., Sutton, R.P. et al. 2013. An Experimental Study on Liquid Loading of Vertical and Deviated Gas Wells. Presented at the SPE Production and Operations Symposium, Oklahoma City, Oklahoma, USA, 23-26 March. SPE-164516-MS. http://dx.doi.org/10.2118/164516-MS.
Skopich, A. 2012. Experimental Study of Surfactant Effect on Liquid Loading in 2-in and 4-in Diameter Vertical Pipes. MSE thesis, University of Tulsa, Tulsa, Oklahoma.
Sutton, R., Cox, S., Lea, J. et al. 2010. Guidelines for the proper application of critical velocity calculations. SPE Prod & Oper 25 (2): 182-194. SPE-120625-PA. http://dx.doi.org/10.2118/120625-PA.
Turner, R.G., Hubbard, M.G., and Dukler, A.E. 1969. Analysis and Prediction of Minimum Flowrate for the Continuous Removal of Liquids from Gas Wells. J Pet Technol 21 (11): 1475–1482. SPE-2198-PA. http://dx.doi.org/10.2118/2198-PA.
van ’t Westende, J.M.C., Kemp, H.K., Belt, R.J. et al. 2007. On the role of droplets in cocurrent annular and churn-annular pipe flow. Int. J. Multiphase Flow 33 (6): 595–615. http://dx.doi.org/10.1016/j.ijmultiphaseflow.2006.12.006.
van ’t Westende, J.M.C. 2008. Droplets in annular-dispersed gas-liquid pipe-flows. PhD thesis, Delft Technical University, Delft, The Netherlands.
Veeken, K., Hu, B., and Schiferli, W. 2010. Gas-Well Liquid-Loading-Field-Data Analysis and Multiphase-Flow Modeling. SPE Prod & Oper 25 (3): 275-284. SPE-123657-PA. http://dx.doi.org/10.2118/123657-PA.
Wallis, G.B. 1969. One Dimensional Two-Phase Flow, Vol 1. New York: McGraw-Hill.
Whalley, P.B. and Hewitt, G.F. 1978. The Correlation of Liquid Entrainment Fraction and Entrainment Rate in Annular Two-Phase Flow. Harwell, Oxfordshire: UKAEA Atomic Energy Research Establishment.
Yuan, G. 2011. Liquid loading problems of natural gas wells. MS thesis, University of Tulsa, Tulsa, Oklahoma.
Zabaras, G., Dukler, A.E., and Moalem-Maron, D. 1986. Vertical upward cocurrent gas-liquid annular flow. AIChE J. 32 (5): 829-843. http://dx.doi.org/10.1002/aic.690320513.
Zhang, H.-Q., Wang, Q., Sarica, C. et al. 2003a. Unified Model for Gas-Liquid Pipe Flow via Slug Dynamics—Part 1: Model Development. J. Energy Resour. Technol. 125 (4): 266-273. http://dx.doi.org/10.1115/1.1615246.
Zhang, H.-Q., Wang, Q., Sarica, C. et al. 2003b. Unified Model for Gas-Liquid Pipe Flow via Slug Dynamics—Part 2: Model Validation. J. Energy Resour. Technol. 125 (4): 274-283. http://dx.doi.org/10.1115/1.1615618.