Variations of Gas/Condensate Relative Permeability With Production Rate at Near-Wellbore Conditions: A General Correlation
- Mahmoud Jamiolahmady (Heriot-Watt University) | Ali Danesh (Heriot-Watt University) | D.H. Tehrani (Heriot-Watt University) | Mehran Sohrabi (Heriot-Watt University)
- Document ID
- Society of Petroleum Engineers
- SPE Reservoir Evaluation & Engineering
- Publication Date
- December 2006
- Document Type
- Journal Paper
- 688 - 697
- 2006. Society of Petroleum Engineers
- 3.2.3 Hydraulic Fracturing Design, Implementation and Optimisation, 5.2 Reservoir Fluid Dynamics, 5.6.4 Drillstem/Well Testing, 5.4.2 Gas Injection Methods, 5.3.1 Flow in Porous Media, 2.2.2 Perforating, 5.4 Enhanced Recovery, 5.2.1 Phase Behavior and PVT Measurements, 5.8.8 Gas-condensate reservoirs, 4.3.4 Scale, 1.2.3 Rock properties, 5.5.8 History Matching, 5.5 Reservoir Simulation, 1.6.9 Coring, Fishing, 4.1.5 Processing Equipment, 4.6 Natural Gas, 4.1.2 Separation and Treating
- 3 in the last 30 days
- 1,318 since 2007
- Show more detail
- View rights & permissions
|SPE Member Price:||USD 5.00|
|SPE Non-Member Price:||USD 35.00|
It has been demonstrated, first by this laboratory and subsequently by other researchers, that the gas and condensate relative permeability can increase significantly by increasing rate, contrary to the common understanding. There are now a number of correlations in the literature and commercial reservoir simulators accounting for the positive effect of coupling and the negative effect of inertia at near-wellbore conditions. The available functional forms estimate the two effects separately and include a number of parameters, which should be determined with measurements at high-velocity conditions. Measurements of gas/condensate relative permeability at simulated near-wellbore conditions are very demanding and expensive.
Recent experimental findings in this laboratory indicate that measured gas/condensate relative permeability values on cores with different characteristics become more similar if expressed in terms of fractional flow instead of the commonly used saturation. This would lower the number of rock curves required in reservoir studies. Hence, we have used a large data bank of gas/condensate relative permeability measurements to develop a general correlation accounting for the combined effect of coupling and inertia as a function of fractional flow. The parameters of the new correlation are either universal, applicable to all types of rocks, or can be determined from commonly measured petrophysical data. The developed correlation has been evaluated by comparing its prediction with the gas/condensate relative permeability values measured at near-wellbore conditions on reservoir rocks not used in its development. The results are quite satisfactory, confirming that the correlation can provide reliable information on variations of relative permeability at near-wellbore conditions with no requirement for expensive measurements.
The process of condensation around the wellbore in a gas/condensate reservoir, when the pressure falls below the dewpoint, creates a region in which both gas and condensate phases flow. The flow behavior in this region is controlled by the viscous, capillary, and inertial forces. This, along with the presence of condensate in all the pores, dictates a flow mechanism that is different from that of gas/oil and gas/condensate in the bulk of the reservoir (Danesh et al. 1989). Accurate determination of gas/condensate relative permeability (kr ) values, which is very important in well-deliverability estimates, is a major challenge and requires an approach different from that for conventional gas/oil systems.
It has been widely accepted that relative permeability (kr ) values at low values of interfacial tension (IFT) are strong functions of IFT as well as fluid saturation (Bardon and Longeron 1980; Asar and Handy 1988; Haniff and Ali 1990; Munkerud 1995). Danesh et al. (1994) were first to report the improvement of the relative permeability of condensing systems owing to an increase in velocity as well as that caused by a reduction in IFT. This flow behavior, referred to as the positive coupling effect, was subsequently confirmed experimentally by other investigators (Henderson et al. 1995, 1996; Ali et al. 1997; Blom et al. 1997). Jamiolahmady et al. (2000) were first to study the positive coupling effect mechanistically capturing the competition of viscous and capillary forces at the pore level, where there is simultaneous flow of the two phases with intermittent opening and closure of the gas passage by condensate. Jamiolahmady et al. (2003) developed a steady-dynamic network model capturing this flow behavior and predicted some kr values, which were quantitatively comparable with the experimentally measured values.
|File Size||1 MB||Number of Pages||10|
Ali, J.K., McGauley, P.J., and Wilson,C.J. 1997. The Effects ofHigh-Velocity Flow and PVT Changes Near the Wellbore on Condensate WellPerformance. Paper SPE 38923 presented at the SPE Annual TechnicalConference and Exhibition, San Antonio, Texas, 5-8 October. DOI:10.2118/38923-MS.
Al-Kharusi, S.B. 2000. Relativepermeability of gas-condensate near wellbore, and gas-condensate-water in bulkof reservoir. PhD thesis, Heriot-Watt U., Edinburgh, U.K.
App, J.F. and Mohanty, M. 2002. Gas andcondensate relative permeability at near critical conditions: capillary andReynolds number dependence. J. Pet. Sci. Eng. 36 (1-2): 111-126.DOI: http://dx.doi.org/10.1016/S0920-4105(02)00269-3.
Asar, H. and Handy, L.L. 1988. Influence of Interfacial Tension onGas/Oil Relative Permeability in a Gas-Condensate System. SPERE3 (1): 257-264. SPE-11740-PA. DOI: 10.2118/11740-PA.
Bardon, C. and Longeron, D.G. 1980. Influence of Very Low InterfacialTension on Relative Permeability. SPEJ 20 (5): 391-401.SPE-7609-PA. DOI: 10.2118/7609-PA.
Blom, S.M.P. and Hagoort, J. 1998a. The Combined Effect of Near-CriticalRelative Permeability and Non-Darcy Flow on Well Impairment by Condensate DropOut. SPEREE 1 (5): 421-429. SPE-51367-PA. DOI:10.2118/51367-PA.
Blom, S.M.P. and Hagoort, J. 1998b. How To Include the Capillary Numberin Gas Condensate Relative Permeability Functions? Paper SPE 49268 preparedfor presentation at the SPE Annual Technical Conference and Exhibition, NewOrleans, 27-30 September. DOI: 10.2118/49268-MS.
Blom, S.M.P., Hagoort, J., and Soetekouw,D.P.N. 1997. Relative Permeabilityat Near-Critical Conditions. Paper SPE 38935 presented at the SPE AnnualTechnical Conference and Exhibition, San Antonio, Texas, 5-8 October. DOI:10.2118/38935-MS.
Coles, M.E. and Hartman, K.J. 1998. Non-Darcy Measurements in Dry Coreand the Effect of Immobile Liquid. Paper SPE 39977 presented at the SPE GasTechnology Symposium, Calgary, 15-18 March.
Dacun L. and Engler, T.W. 2001. Literature Review on Correlations ofthe Non-Darcy Coefficient. Paper SPE 70015 presented at the SPE PermianBasin Oil and Gas Recovery Conference, Midland, Texas, 15-17 May. DOI:10.2118/70015-MS.
Danesh, A., Khazam, M., Henderson, G.D.,Tehrani, D.H., and Peden, J.M. 1994. Gas Condensate Recovery Studies. Paperpresented at the DTI Improved Oil Recovery and Research Dissemination Seminar,London, June.
Danesh, A., Krinis, A., Henderson, G.D.,and Peden, J.M. 1989. Visual Investigation of the Retrograde Phenomena and GasCondensate Flow in Porous Media. Paper presented at the 5th European EORSymposium, Budapest, Hungary, 25-27 April.
Danesh, A., Tehrani, D.H., Henderson,G.D., Jamiolahmady, M., Ataei, R., and Ireland, S. 2002. Gas CondensateRecovery Studies. Paper presented at the DTI Improved Oil Recovery and ResearchDissemination Seminar, London, 25 June.
ECLIPSE Reference Manuals, 2002.Technical Description, Chapters 6-10, Version 2002A. Abingdon, U.K.:Schlumberger.
Haniff, M.S. and Ali, J.K. 1990. Relative Permeability and Low TensionFluid Flow in Gas Condensate Systems. Paper SPE 20917 presented at the SPEEuropean Petroleum Conference, The Hague, 21-24 October. DOI:10.2118/20917-MS.
Henderson, G.D., Danesh, A., Al-Kharousi,B., and Tehrani, D.H. 2000a. Generating reliable gas condensate relativepermeability data used to develop a correlation with capillary number. J.Pet. Sci. Eng. 25 (1-2): 79-91. DOI: http://dx.doi.org/10.1016/S0920-4105(00)00004-8.
Henderson, G.D., Danesh, A., Tehrani,D.H., and Al-Kharusi, B. 2000b. The Relative Significance of PositiveCoupling and Inertial Effects on Gas Condensate Relative Permeabilities at HighVelocity. Paper SPE 62933 presented at the SPE Annual Technical Conferenceand Exhibition, Dallas, 1-4 October. DOI: 10.2118/62933-MS.
Henderson, G.D., Danesh, A., and Tehrani,D.H. 2001. Effect of positive rate sensitivity and inertia on gas condensaterelative permeability at high velocity. Petroleum Geoscience 7(1): 45-50.
Henderson, G.D., Danesh, A., Tehrani,D.H., and Peden, J.M. 1995. The effect of velocity and interfacial tension onthe relative permeability of gas condensate fluids in the wellbore region.Paper presented at the 8th European IOR Symposium, Vienna, Austria, 15-17May.
Henderson, G.D., Danesh, A., Tehrani,D.H., Al-Shaldi, S., and Peden, J.M. 1996. Measurement and Correlation of GasCondensate Relative Permeability by the Steady-State Method. SPEJ1 (2): 191-201. SPE-31065-PA. DOI: 10.2118/31065-PA.
Jamiolahmady, M., Danesh, A., Tehrani,D.H., and Duncan, D.B. 2000. A mechanistic model of gas-condensate flow inpores. Transport in Porous Media 41 (1): 17-46. DOI: http://dx.doi.org/10.1023/A:1006645515791.
Jamiolahmady, M., Danesh, A., Tehrani,D.H., and Duncan, D.B. 2003. Positive Effect of Flow Velocity on Gas-CondensateRelative Permeability: Network Modelling and Comparison With ExperimentalResults. Transport in Porous Media 52 (2): 159-183. DOI: http://dx.doi.org/10.1023/A:1023529300395.
Mott, R., Cable, A., and Spearing, M.2000. Measurements and Simulationof Inertial and High Capillary Number Flow Phenomena in Gas-Condensate RelativePermeability. Paper SPE 62932 presented at the SPE Annual TechnicalConference and Exhibition, Dallas, 1-4 October. DOI:10.2118/62932-MS.
Munkerud, P.K. 1995. The effect ofinterfacial tension and spreading on relative permeability in gas condensatesystems. Paper presented at the 8th European IOR Symposium, Vienna, Austria,15-17 May.
Narayanaswamy, G., Sharma, M.M., andPope, G.A. 1999. Effect ofHeterogenity on the Non-Darcy Flow Coefficient. SPEREE 2 (3):296-302. SPE-56881-PA. DOI: 10.2118/56881-PA.
Pope, G.A., Wu, W., Narayanaswamy, G.,Delshad, M., Sharma, M., and Wang, P. 1998. Modeling Relative PermeabilityEffects in Gas-Condensate Reservoirs. Paper SPE 49266 prepared forpresentation at the SPE Annual Technical Conference and Exhibition, NewOrleans, 27-30 September. DOI: 10.2118/49266-MS.
VIP Technical Reference Manuals. 2002.Executive Technical Reference, Chapter 35, 495-507, Version 2003.R4. Houston:Landmark Graphics Corp.
Whitson, C.H., Fevang, O., and Sævareid,A. 1999. Gas Condensate RelativePermeability for Well Calculations. Paper SPE 56476 presented at the SPEAnnual Technical Conference and Exhibition, Houston, 3-6 October. DOI:10.2118/56476-MS.