Lessons Learned From Using Viscoelastic Surfactants in Well Stimulation
- Hisham A. Nasr-El-Din (Saudi Aramco) | Mathew M. Samuel (Schlumberger)
- Document ID
- Society of Petroleum Engineers
- SPE Production & Operations
- Publication Date
- February 2007
- Document Type
- Journal Paper
- 112 - 120
- 2007. Society of Petroleum Engineers
- 5.1.1 Exploration, Development, Structural Geology, 2.5.2 Fracturing Materials (Fluids, Proppant), 2.2.3 Fluid Loss Control, 1.10 Drilling Equipment, 3.3.1 Production Logging, 5.2 Reservoir Fluid Dynamics, 5.8.7 Carbonate Reservoir, 4.2.3 Materials and Corrosion, 4.1.2 Separation and Treating, 1.8 Formation Damage, 1.6 Drilling Operations, 3.2.4 Acidising, 3 Production and Well Operations, 4.3.4 Scale
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Viscoelastic surfactant systems are used in the industry for several applications. Initially, the application was focused on low-friction and solids-suspension (fracturing and CT-cleanout) characteristics of the fluid. In the last 4 years, the application of viscoelastic surfactants was extended to acid-based systems for carbonate stimulation. These surfactants have the ability to significantly increase the apparent viscosity and elastic properties of the treating fluids. This is because of the ability of surfactant monomers to associate and form rod-shaped micellar structures under certain conditions.
Viscoelastic surfactant-based acid systems have been used in Saudi Arabian fields in matrix acid stimulation, and in leakoff control acids during acid-fracturing treatments. These surfactants were used to provide diversion during acidizing of vertical, long horizontal, and multilateral wells. They were used in sour environments where hydrogen sulfide levels reached nearly 10 mol%. They were also utilized in gas wells to reduce acid leakoff, and create deep fractures in dolomitic carbonate reservoirs (250 to 275°F). In addition, they were successfully employed to stimulate seawater injectors and disposal wells where the bottomhole temperature was in the range of 100 to 150°F.
More than 250 wells (oil, gas, water injectors, and disposal wells) were treated with viscoelastic surfactant-based acid systems. The acid was placed either by bullheading, by using coiled tubing with or without a tractor. In some cases, these treatments included stages of emulsified or regular acids. All these wells responded positively to the treatment. There were no operational problems encountered during pumping these acids even when low-permeability reservoirs were treated. Because these acid systems do not contain polymers, there was no need to flow back water injectors. The spent acid in oil and gas wells was lifted from the treated wells in a very short period of time. Finally, wells treated with surfactant-based acid systems showed sustained performance for longer times than those treated with other acid systems.
Matrix acidizing and fracturing treatments have been used to enhance the performance of oil, gas, and water wells for several decades. Water-soluble and acid-soluble polymers have been used in these treatments to increase the viscosity of the treatment fluids and hence enhance diversion during matrix acidizing treatments. High-viscosity fluids are needed during acid-fracturing treatments to reduce leakoff rate during acid injection into the fracture.
Various chemicals were developed to enhance acid diversion by increasing the viscosity of the injected acid. Depending on the viscosifiying agent, these systems can be divided into two main categories: polymer-based and surfactant-based.
Acid-soluble polymers have been used to increase the viscosity of HCl, and to improve its performance (Pabley et al. 1982; Crowe et al. 1989). As the viscosity of the acid increases, the rate of acid spending decreases and, as a result, deeper acid penetration can be achieved (Deysarkar et al. 1984).
The addition of uncross-linked polymers to HCl improved acid penetration; however, acid placement did not significantly improve (Yeager and Shuchart 1997). Crosslinked acids were introduced in the mid 70's as was cited by Metcalf et al. (2000). These acids have much higher viscosity than regular acids or acids containing uncrosslinked polymers. Two types of crosslinked acids are available. The first type consists of a polymer, a crosslinker, and other acid additives (Saxon et al. 2000). The acid in this case is crosslinked on the surface and reaches the formation already crosslinked. The second type of crosslinked acid consists of a polymer, a crosslinker, a buffer, a breaker, and other acid additives (e.g., corrosion inhibitors and surfactants). The acid in this case reaches the formation uncrosslinked, and the crosslinking reaction occurs in the formation (Taylor and Nasr-El-Din 2003).
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Al-Ghamdi, A.H., Nasr-El-Din, H.A., Al-Qahtani, A.A., andSamuel, M. 2004. Impact of Acid Additives on the Rheological Properties ofViscoelastic Surfactants and Their Influence on FieldApplication. Paper SPE 89418 presented at the SPE/DOE Symposium onImproved Oil Recovery, Tulsa,17-21 April. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=89418-MS.
Al-Muhareb M.A., Nasr-El-Din, H.A.,Samuel, E., Marcinew, R.P., and Samuel, M. 2003. Acid Fracturing of Power WaterInjectors: A New Field Application Using Polymer-Free Fluids. Paper SPE82210 presented at the SPE European Formation Damage Conference, The Hague,13-14 May. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=82210-MS.
Al-Mutawa, M., Al-Anzi, E., Jemmali, M.,Chang, F., Samuel, E., and Samuel, M. 2005. Zero-Damaging Stimulation andDiversion Fluid: Field Cases From the Carbonate Formations in North Kuwait.SPEPF 20 (2): 94-105. SPE-80225-PA. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=80225-PA.
Bartko, K.M., Nasr-El-Din, H.A., Rahim,Z., and Al-Muntasheri, G.A. 2003. Acid Fracturing of a Carbonate GasReservoir: The Impact of Acid Type and Lithology on Fracture Half Length andWidth. Paper SPE 84130 presented at the SPE Annual Conference andExhibition, Denver, 5-8 October. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=84130-MS.
Bhalla, K. 1995. Coiled Tubing Extended ReachTechnology. Paper SPE 30404 presented at the SPE Offshore EuropeConference, Aberdeen, Scotland, 5-8 September. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=30404-MS.
Card, R.J. et al. 1999. Methods forLimiting the Inflow of Formation Water and for Stimulating SubterraneanFormations.U.S. Patent No. 5,979,557.
Chang, F.F., Thomas, R.L., and Fu, D.K.1998. A New Material and NovelTechnique for Matrix Stimulation in High-Water-Cut Oil Wells. Paper SPE39592 presented at the SPE Formation Damage Control Conference, Lafayette,Louisiana, 18-19 February. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=39592-MS.
Chang, F.F., Love, T., Affeld, C.J.,Blevins, J.B. III, Thomas, R.L., and Fu, D.K. 1999. Case Study of a Novel Acid-DiversionTechnique in Carbonate Reservoirs. Paper SPE 56529 presented at the SPEAnnual Technical Conference and Exhibition, Houston, 3-6 October. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=56529-MS.
Chang, F., Qu, Q., and Frenier, W. 2001a.A Novel Self-Diverting-AcidDeveloped for Matrix Stimulation of Carbonate Reservoirs. Paper SPE65033 presented at the SPE International Symposium on Oilfield Chemistry,Houston, 13-16 February. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=65033-MS.
Chang, F.F., Acock, A.M., Geoghagan, A.,and Huckabee, T. 2001b. Experiencein Acid Diversion in High-Permeability Deepwater Formations Using ViscoelasticSurfactant. Paper SPE 68919 presented at the SPE European FormationDamage Conference, The Hague, 21-22 May. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=68919-MS.
Crowe, C.W., Hutchinson, B.H., andTrittipo, B.L. 1989. Fluid-LossControl: The Key to Successful Acid Fracturing. SPEPE 4 (3):215-220; Trans., AIME, 287. SPE-16883-PA. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=16883-PA.
Deysarkar, A.K., Dawson, J.C., Sedillo,L.P., and Knoll-Davis, S. 1984. Crosslinked Acid Gel. J. Canadian PetroleumTechnology 24: 26.
Fu, D. and Chang, F. 2005. Compositionsand Methods for Treating a Subterranean Formation. U.S. Patent No. 6,929,070 B2(16 August 2005).
Gdanski, R. 2005. Recent Advances in CarbonateStimulation. Paper IPTC 10693 presented at the SPE International PetroleumConference, Doha, Qatar, 21-23 November.
Haukvik, J. 1994. Development of DownHole Tractors for Coiled Tubing and Wirelines. Paper presented at the SPEEuropean Coiled Tubing Roundtable, Aberdeen, 18-19 October.
Lynn, J.D. and Nasr-El-Din, H.A. 2001. A Core-Based Comparison of theReaction Characteristics of Emulsified and In-Situ Gelled Acids in Low-Permeability, High-Temperature, Gas-Bearing Carbonates. Paper SPE65386 presented at the SPE International Symposium on Oilfield Chemistry,Houston, 13-16 February. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=65386-MS.
Metcalf, S., Lopez, H., Hoff, C., andWoo, G. 2000. Gas Production FromLow-Permeability Carbonates Enhanced Through Usage of a New Acid PolymerSystem. Paper SPE 59756 presented at the SPE/CERI Gas Technology Symposium,Calgary, 3-5 April. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=59756-MS.
Mohamed, S.K., Nasr-El-Din, H.A., andAl-Furaidan, Y.A. 1999. AcidStimulation of Power Water Injectors and Saltwater Disposal Wells in aCarbonate Reservoir in Saudi Arabia: Laboratory Testing and Field Results.Paper SPE 56533 presented at the SPE Annual Technical Conference andExhibition, Houston, 3-6 October. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=56533-MS.
Mohamed, S., Nasr-El-Din, H.A., Dossary,K., McClelland, K., and Samuel, M. 2002. Enhancement of Stimulation Treatmentof Water Injection Wells Using a New Polymer-Free Diversion System. PaperSPE 78588 presented at the SPE International Symposium on Formation DamageControl, Abu Dhabi International Petroleum Exhibition and Conference, AbuDhabi, 13-16 October. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=78588-MS.
Nasr-El-Din, H.A. and Al-Humaidan, A.Y.2001. Iron Sulfide Scale:Formation, Removal and Mitigation. Paper SPE 68315 presented at the SPEInternational Symposium on Oilfield Scale, Aberdeen, 30-31 January. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=68315-MS.
Nasr-El-Din, H.A., Taylor, K.C., andAl-Hajji, H.H. 2002a. Propagationof Crosslinkers Used in In-Situ Gelled Acids in Carbonate Reservoirs. PaperSPE 75257 presented at the SPE/DOE Improved Oil Recovery Symposium, Tulsa,13-17 April. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=75257-MS.
Nasr-El-Din, H.A., Al-Mutairi, S.H.,Al-Jari, M., Metcalf, A.S., and Walters, W. 2002b. Stimulation of a Deep Sour GasReservoir Using Gelled Acid. Paper SPE 75501 presented at the SPE GasTechnology Symposium, 30 April-2 May. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=75501-MS.
Nasr-El-Din, H.A., Al-Humaidan, A.Y.,Fadhel, B.A., Frenier, W.W., and Hill, D.G. 2002c. Investigation of Sulfide Scavengersin Well-Acidizing Fluids. SPEPF 17 (4): 229-235.SPE-80289-PA. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=80289-PA.
Nasr-El-Din H.A., Al-Driweesh, S.,Al-Muntasheri, G.A., Marcinew, R., Daniels, J., and Samuel, M. 2003a. Acid Fracturing HP/HT Gas Wells Usinga Novel Surfactant-Based Fluid System. Paper SPE 84516 presented at the SPEAnnual Technical Conference and Exhibition, Denver, 5-8 October. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=84516-MS.
Nasr-El-Din H.A., Samuel, E., and Samuel,M. 2003b. Application of a NewClass of Surfactants in Stimulation Treatments. Paper SPE 84898 presentedat the SPE International Improved Oil Recovery Conference, Kuala Lumpur, 20-21October. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=84898-MS.
Nasr-El-Din, H.A., Al-Mohammed, A.M.,Al-Shurei, A.A., Merwat, N.K., Erbil, M.M., and Samuel, M. 2004a. Matrix Stimulation of Water DisposalWells Using a Viscoelastic-Surfactant-Based Acid. Paper SPE 88588 presentedat the SPE Asia Pacific Oil and Gas Conference and Exhibition, Perth,Australia, 18-20 October. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=88588-MS.
Nasr-El-Din, H.A., Al-Habib, N.S.,Jemmali, M., Lahmadi, A., and Samuel, M. 2004b. A Novel Technique To AcidizeHorizontal Wells With Extended Reach. Paper SPE 90385 presented at the SPEAnnual Technical Conference and Exhibition, Houston, 26-29 September. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=90385-MS.
Nasr-El-Din, H.A. et al. 2006a. Acid Fracturing of Deep Gas WellsUsing a Surfactant-Based Acid: Long-Term Effects on Gas Production Rate.Paper SPE 102469 presented at the SPE Annual Technical Conference andExhibition, San Antonio, Texas, 24-27 September. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=102469-MS.
Nasr-El-Din, H.A., Al-Habib N.S.,Al-Mumen, A.A., Jemmali, M., and Samuel, M. 2006b. A New Effective Stimulation TreatmentMethodology for Long Horizontal Wells Using Viscoelastic-Surfactant TreatmentFluid. Paper SPE 86516 submitted to SPEPO (in process).
Pabley, A.S., Ewing, B.C., and Callaway,R.E. 1982. Performance ofCrosslinked Hydrochloric Acid in the Rocky Mountain Region. Paper SPE 10877presented at the SPE Rocky Mountain Regional Meeting, Billings, Montana, 19-21May. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=10877-MS.
Samuel, M. 2001. Methods of FracturingSubterranean Formations. U.S. Patent No. 6,306,800.
Samuel, M. 2003. Cleaner Wells ProduceBetter Results. Lyle, D. (ed.). Hart's E&P 40-43.
Samuel, M. and Sandhu, W. 2004.Non-Damaging Self-Diverting Acid Stimulations Revive an Egyptian Oil Field.World Oil 225 (2): 88-91
Saxon, A., Chariag, B., and Abdel Rahman,M.R. 2000. An Effective MatrixDiversion Technique for Carbonate Reservoirs. SPEDC 15(1): 57-62. SPE-62173-PA. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=62173-PA.
Taylor, K.C. and Nasr-El-Din, H.A 2002.Coreflood Evaluation of In-SituGelled Acids. Paper SPE 73707 presented at the SPE International Symposiumand Exhibition on Formation Damage Control, Lafayette, Louisiana, 20-21February. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=73707-MS.
Taylor, K.C. and Nasr-El-Din, H.A. 2003.Laboratory Evaluation of In-SituGelled Acids for Carbonate Reservoirs. SPEJ 8 (4): 426-434.SPE-71694 -PA. DOI:http://www.spe.org/elibrary/servlet/spepreview?id=71694-PA.
Vinod, P.S., Chang, F., and Samuel, M.1997. U.S. Patent No. 5,979,557 (9 November 1997).
Yeager, V. and Shuchart, C. 1997. In SituGels Improve Formation Acidizing. Oil & Gas J.95:70.