A Comprehensive Model of High-Rate Matrix-Acid Stimulation for Long Horizontal Wells in Carbonate Reservoirs: Part II--Wellbore/Reservoir Coupled-Flow Modeling and Field Application
- Kenji Furui (ConocoPhillips) | Robert C. Burton (ConocoPhillips) | David W. Burkhead (ConocoPhillips) | Nabeel A. Abdelmalek (ConocoPhillips) | Alfred D. Hill (Texas A&M University) | Ding Zhu (Texas A&M University) | Manabu Nozaki (Texas A&M University)
- Document ID
- Society of Petroleum Engineers
- SPE Journal
- Publication Date
- March 2012
- Document Type
- Journal Paper
- 280 - 291
- 2012. Society of Petroleum Engineers
- 4.1.2 Separation and Treating, 5.8.7 Carbonate Reservoir, 3.2.4 Acidising, 5.1.5 Geologic Modeling, 2.2.2 Perforating
- wormhole, skin factor, wellbore-reservoir coupled flow model, matrix acidizing, production and operations
- 6 in the last 30 days
- 1,211 since 2007
- Show more detail
- View rights & permissions
|SPE Member Price:||USD 10.00|
|SPE Non-Member Price:||USD 30.00|
Successful acid stimulation of long-horizontal-well intervals in carbonate reservoirs requires effective acid distribution along the entire reservoir length. Such treatments also require large volumes of acid and seawater/brine injection at sufficiently high injection rates to drive the acid wormholes deep into the reservoir. Under these flowing conditions, significantly large tubing friction loss is anticipated unless optimal friction reducer performance in the tubing is maintained throughout the pumping operation. Because prediction of wormhole penetration and corresponding skin factor depends on analysis of downhole-injection pressures at the reservoir face, it is crucial to properly account for these hydrostatic and friction changes prior to evaluation of wormhole length and skin factor.
In this study, an integrated flow model has been developed to predict the wellbore-pressure profile and wormhole distribution by tracking the movement of the acid in the wellbore and the formation. The wellbore-flow model is based on steady-state, 1D, pressure-based nodal method. The segmented wellbore in the reservoir interval is then coupled with analytical transient reservoir-flow models. The wormhole propagation in the formation is calculated based on the modified Buijse-Glasbergen correlation and upscaling model developed in our earlier work. The resultant wormholing skin factor is calculated by simulating and updating the changing well injectivity along the entire injection interval at every timestep. The model developed in this work is applicable for both fully completed wells (i.e., radial flow) and selectively completed perforation-cluster wells (i.e., spherical flow) typically employed in carbonate reservoirs.
Analysis of injection rates and pressures during acid treatment provides engineers with a way to determine the varying injectivity and tubing friction as stimulation proceeds. The model presented here can be used as a forward model for analyzing real-time treatment rate and pressure histories and can also be used to review past treatments to improve future treatment designs. Using actual field-stimulation data, we also discuss key elements to successful stimulation planning and the diagnosis of matrix-acid treatments to achieve effective wormhole coverage for horizontal completions in carbonate formations.
|File Size||2 MB||Number of Pages||12|
Barree, R.D., Barree, V.L., and Craig, D.P. 2007. HolisticFracture Diagnostics. Paper SPE 107877 presented at the Rocky Mountain Oil andGas Technology Symposium, Denver, 16-18 April. http://dx.doi.org/10.2118/107877-MS.
Brigham, W.E., Peden, J.M., Ng, K.F., and O'Neill, N. 1980. TheAnalysis of Spherical Flow With Wellbore Storage. Paper SPE 9294 presented atthe SPE Annual Technical Conference and Exhibition, Dallas, 21-24 September. http://dx.doi.org/10.2118/9294-MS.
Crump, J.B. and Conway, M.W. 1988. Effects of Perforation-EntryFriction on Bottomhole Treating Analysis. J Pet Technol 40(8): 1041-1048. SPE-15474-PA. http://dx.doi.org/10.2118/15474-PA.
Eckerfield, L.D., Zhu, D., Hill, D.A, Robert, J.A., and Bartko,K.M. 2000. Fluid Placement Model for Horizontal-Well Stimulation. SPE Drill& Compl 15 (3): 185-190. SPE-65408-PA. http://dx.doi.org/10.2118/65408-PA.
Furui, K., Burton, R.C., Burkhead, D.W., Abdelmalek, N.A.,Hill, A.D., Zhu, D., and Nozaki, M. 2010. A Comprehensive Model of High-RateMatrix Acid Stimulation for Long Horizontal Wells in Carbonate Reservoirs.Paper SPE 134265 presented at the SPE Annual Technical Conference andExhibition, Florence, Italy, 19-22 September. http://dx.doi.org/10.2118/134265-MS.
Furui, K., Zhu, D., and Hill, A.D. 2003. A Rigorous FormationDamage Skin Factor and Reservoir Inflow Model for a Horizontal Well. SPE ResEng 18 (3): 151-157. SPE-84964-PA. http://dx.doi.org/10.2118/84964-PA.
Furui, K., Zhu, D., and Hill, A.D. 2005. A ComprehensiveSkin-Factor Model of Horizontal-Well Completion Performance. SPE Prod &Fac 20 (3): 207-220. SPE-84401-PA. http://dx.doi.org/10.2118/84401-PA.
Furui, K., Zhu, D., and Hill, A.D. 2008. A New Skin FactorModel for Perforated Horizontal Wells. SPE Drill & Compl 23 (3): 205-215. SPE-77363-PA. http://dx.doi.org/10.2118/77363-PA.
Greyvenstein, G.P. and Laurie, D.P. 1994. A segregated CFD approach to pipenetwork analysis. Int. J. Num. Meth. Eng. 37 (21):3685-3705. http://dx.doi.org/10.1002/nme.1620372107.
Joseph, J.A. and Koederitz, L.F. 1985. Unsteady-State SphericalFlow with Storage and Skin. SPE J. 25 (6): 804-822.SPE-12950-PA. http://dx.doi.org/10.2118/12950-PA.
Lee, J.W., Rollins, J.B., and Spivey, J.P. 2003. PressureTransient Testing. Textbook Series, SPE, Richardson, Texas 9:225.
Mishra, V., Zhu, D., Hill, A.D., and Furui, K. 2007. AnAcid-Placement Model for Long Horizontal Wells in Carbonate Reservoirs. PaperSPE 107780 presented at the European Formation Damage Conference, Scheveningen,The Netherlands, 30 May-1 June. http://dx.doi.org/10.2118/107780-MS.
Pretorius, J.J., Malan, A.G., and Visser, J.A. 2008. A flow networkformulation for compressible and incompressible flow. International Journalof Numerical Methods for Heat & Fluid Flow 18 (2):185-201. http://dx.doi.org/10.1108/09615530810846338.
Raghavan, R. and Clark, K.K. 1975. Vertical Permeability fromLimited Entry Flow Tests in Thick Formations. SPE J. 15(1): 65-73. SPE-4556-PA. http://dx.doi.org/10.2118/4556-PA.
Rodriguez-Nieto, R. and Carter, R.D. 1972. UnsteadyThree-Dimensional Gas Flow in Thick Reservoirs. Paper SPE 4266 available fromSPE, Richardson, Texas.
White, F.M. 1986. Fluid Mechanics, second edition. NewYork: McGraw-Hill Higher Education.