Simultaneous Acid Diversion and Water Control in Carbonate Reservoirs: A Case History From Saudi Arabia
- Ali A. Al-Taq (Saudi Aramco) | Hisham A. Nasr-El-Din (Texas A&M University) | Jimmy K. Beresky (Saudi Aramco) | Khalid M. Al-Naimi (Saudi Aramco) | Leopoldo Sierra (Halliburton) | Larry S. Eoff (Halliburton Energy Services Group)
- Document ID
- Society of Petroleum Engineers
- SPE Reservoir Evaluation & Engineering
- Publication Date
- October 2008
- Document Type
- Journal Paper
- 882 - 891
- 2008. Society of Petroleum Engineers
- 1.6.9 Coring, Fishing, 1.11 Drilling Fluids and Materials, 1.8 Formation Damage, 5.8.1 Tight Gas, 3.2.4 Acidising, 5.8.7 Carbonate Reservoir, 5.6.4 Drillstem/Well Testing, 5.4.7 Chemical Flooding Methods (e.g., Polymer, Solvent, Nitrogen, Immiscible CO2, Surfactant, Vapex), 1.14 Casing and Cementing, 2.5.2 Fracturing Materials (Fluids, Proppant), 5.1 Reservoir Characterisation, 4.2.3 Materials and Corrosion, 5.2.1 Phase Behavior and PVT Measurements, 1.10 Drilling Equipment, 3 Production and Well Operations, 2.2.2 Perforating, 3.3.1 Production Logging, 4.1.5 Processing Equipment, 4.1.2 Separation and Treating
- 1 in the last 30 days
- 1,635 since 2007
- Show more detail
- View rights & permissions
|SPE Member Price:||USD 12.00|
|SPE Non-Member Price:||USD 35.00|
Matrix acidizing and water control are usually addressed as two separate issues. Associative polymers can be used to simultaneously achieve effective acidizing and water control during a single treatment. A polymer-based treatment was applied in an offshore, perforated vertical well with two sets of perforations in a carbonate reservoir in Saudi Arabia. The acid treatment was needed to restore the productivity of the upper set of perforations and reduce water production from the lower set of perforations.
Experimental studies were carried out to investigate the potential use of associative polymers to control water mobility and act as an acid diverter. Coreflood experiments were conducted on reservoir cores at downhole conditions (temperature of 200°F and pressure of 3,500 psi). Extensive laboratory testing showed that associative polymers had no significant effect on the relative permeability to oil. However, the relative permeability to water was significantly reduced.
This paper presents a case history where an associative polymer was applied during matrix acid treatment of a damaged well. The treatment included two stages of associative polymer solutions and 20 wt% HCl with additives. Post-stimulation treatment production data showed that oil rate increased 11.18-fold, whereas water rate decreased 1.7-fold, resulting in a reduction in the water cut from 75 to 14 vol%.
The production logging tool (PLT) results indicated that the associative polymer was effective in diverting the acid into the oil producing zone. The upper set of perforations was producing most of the fluid, which further confirmed that the associative polymer significantly reduced water production from the lower zone.
Matrix acidizing and water control are two important treatments conducted to enhance well performance. These treatments are commonly addressed as two separate issues. Associative polymers can be used to simultaneously achieve effective acidizing and water control utilizing a single treatment (Eoff et al. 2005).
Acid diversion is an important issue contributing to the success of any matrix acid stimulation treatment. For this reason, extensive laboratory studies and field applications have been performed on several acid diverting agents as reported in the literature. Among the techniques that have been applied to improve acid coverage are: mechanical (packers, ball sealers, and particulate diverting agents) and chemicals (foam, polymers, and in-situ-gelled fluids). More recently, viscoelastic surfactants have been used extensively for diversion during matrix acid treatments, and have shown a tendency to reduce water production as reported by Nasr-El-Din et al. (2006).
Relative permeability modifiers, commonly used for water control, can also be utilized for acid diversion. They can act simultaneously to enhance diversion during matrix acid treatments and impair water mobility. Eoff et al. (2005) presented laboratory and field tests, which showed that associative polymers could provide both goals in sandstone reservoirs. However, a few studies considered application of associative polymers to divert and control water production in carbonate formations. Therefore, the objectives of the present study are to: (1) assess the effectiveness of associative polymers in reducing brine permeability in carbonate cores, (2) design a polymer-based treatment to control water and divert acid in matrix treatments, and (3) evaluate the use of associative polymers based on field application.
This paper presents laboratory data that support the use of this new technology in carbonate reservoirs. It will also give for the first time field results on the application of associative polymers in a carbonate reservoir in Saudi Arabia. Field data were in good agreement with laboratory results.
|File Size||3 MB||Number of Pages||10|
Audibert-Hayet, A., Rousseau, L., McGregor, W.M., and Nicora, L.F. 1999. Novel Hydrophobically ModifiedNatural Polymers for Non-Damaging Fluids. Paper SPE 56965 presented at theOffshore Europe Oil and Gas Exhibition and Conference, Aberdeen, 7-10September. DOI: 10.2118/56965-MS.
Chauveteau, G., Denys, K., and Zaitoun, A. 2002. New Insight on Polymer AdsorptionUnder High Flow Rates. Paper SPE 75183 presented at the SPE/DOE ImprovedOil Recovery Symposium, Tulsa, 13-17 April. DOI: 10.2118/75183-MS.
Dalrymple, E.D., Eoff, L., Reddy, B.R., Botermans, C.W., Brown, D., andBrown, S. 2000. Studies of aRelative Permeability Modifier Treatment Performed Using Multitap FlowCells. Paper SPE 59346 presented at the SPE/DOE Improved Oil RecoverySymposium, Tulsa, 3-5 April. DOI: 10.2118/59346-MS.
Eoff, L., Dalrymple, D., and Reddy, B.R. 2005. Development of Associative PolymerTechnology for Acid Diversion in Sandstone and Carbonate Lithology.SPEPF 20 (3): 250-256. SPE-89413-PA. DOI: 10.2118/89413-PA.
Eoff, L., Dalrymple, D., Reddy, B.R., Morgan, J., and Frampton, H. 2003. Development of a HydrophobicallyModified Water-Soluble Polymer as Selective Bullhead System forWater-Production Problems. Paper SPE 80206 presented at the InternationalSymposium on Oilfield Chemistry, Houston, 5-7 February. DOI:10.2118/80206-MS.
Glass, J.E. ed. 1996. Hydrophilic Polymers: Performance withEnvironmental Acceptance, 248. Washington, DC: Advances in ChemistrySeries, American Chemical Society.
Lijian, D. and Biao, W. 1995. Hydrophobically AssociatingTerpolymer and its Complex With a Stabilizer in Brine for Enhanced OilRecovery. Paper SPE 29007 presented at the SPE International Symposium onOilfield Chemistry, San Antonio, Texas, USA, 14-17 February. DOI:10.2118/29007-MS.
McCormick, C.L., Bock, J., and Schulz, D.N. 1989. Encyclopedia of PolymerScience and Engineering, Volume 17, second edition, ed. Mark, H.F.,Bikales, N.M., Overberger, C.G., Menges, G.T., and Kroschwitz, J.I., 730. NewYork: Wiley-Interscience.
Nasr-El-Din, H.A., Al-Habib, N.S., Al-Mumen, A.A., Jemmali, M., and Samuel,M. 2006. A New EffectiveStimulation Treatment for Long Horizontal Wells Drilled in CarbonateReservoirs. SPEPO 21 (3): 330-338. SPE-86516-PA. DOI:10.2118/86516-PA.
Nasr-El-Din, H.A., Al-Mutairi, S.H., and Al-Driweesh, S.M. 2002. Lessons Learned From Acid PickleTreatments of Deep/Sour Gas Wells. Paper SPE 73706 presented at theInternational Symposium and Exhibition on Formation Damage Control, Lafayette,Louisiana, USA, 20-21 February. DOI: 10.2118/73706-MS.
Taylor, K.C. and Nasr-El-Din, H.A. 1998. Water-solublehydrophobically associating polymers for improved oil recovery: A literaturereview. J. Pet. Sci. Eng. 19 (3-4): 265-280.DOI:10.1016/S0920-4105(97)00048-X.
Volpert, E., Selb, J., and Candau, F. 1998. Adsorption of hydrophobicallyassociating polyacrylamides on clay. Langmuir 14 (7):1870-1879. DOI:10.1021/la970358h.
Zaitoun, A. and Chauveteau, G. 1998. Effect of Pore Structure and ResidualOil on Polymer Bridging Adsorption. Paper SPE 39674 presented at theSPE/DOE Improved Oil Recovery Symposium, Tulsa, 19-22 April. DOI:10.2118/39674-MS.