Sweep-Improvement Options for the Daqing Oil Field
- Authors
- Dongmei Wang (Daqing Research Institute) | Peihui Han (PetroChina Co. Ltd.) | Zhenbo Shao (PetroChina Co. Ltd.) | Weihong Hou (Daqing Oilfield Company Ltd.) | Randall S. Seright (New Mexico Tech)
- DOI
- https://doi.org/10.2118/99441-PA
- Document ID
- SPE-99441-PA
- Publisher
- Society of Petroleum Engineers
- Source
- SPE Reservoir Evaluation & Engineering
- Volume
- 11
- Issue
- 01
- Publication Date
- February 2008
- Document Type
- Journal Paper
- Pages
- 18 - 26
- Language
- English
- ISSN
- 1094-6470
- Copyright
- 2008. Society of Petroleum Engineers
- Disciplines
- 4.3.4 Scale, 5.2.1 Phase Behavior and PVT Measurements, 4.1.2 Separation and Treating, 5.4.10 Microbial Methods, 5.7.2 Recovery Factors, 5.4.1 Waterflooding, 5.4 Enhanced Recovery, 5.4.7 Chemical Flooding Methods (e.g., Polymer, Solvent, Nitrogen, Immiscible CO2, Surfactant, Vapex), 5.1 Reservoir Characterisation, 5.3.4 Reduction of Residual Oil Saturation, 2.5.2 Fracturing Materials (Fluids, Proppant), 5.6.5 Tracers, 5.1.2 Faults and Fracture Characterisation
- Downloads
- 5 in the last 30 days
- 1,887 since 2007
- Show more detail
- View rights & permissions
SPE Member Price: | USD 12.00 |
SPE Non-Member Price: | USD 35.00 |
Summary
This paper investigates the potential of various approaches for improving sweep in parts of the Daqing oil field that have been enhanced-oil-recovery (EOR) targets. Our studies indicated that the polymer flood should have provided excellent sweep throughout the vast majority of the patterns under consideration. However, because alkaline/surfactant/polymer (ASP) flooding is being considered to increase recovery efficiency from the Daqing oil field, mobility control and sweep improvement will be especially important and challenging during implementation of any future ASP process.
Fractures were present in a number of Daqing wells (both injectors and producers). Because the fractures were narrow and far from the wellbore, severe channeling did not occur. On the contrary, fractures near the wellbore aided reservoir sweep. Near-wellbore fractures increased the injectivity index substantially during the injection of polymer solutions and increased oil-productivity index in the production wells. These observations may be valuable during implementation of future floods where very-low-mobility chemical (i.e., ASP) banks must be injected to maintain mobility control.
Several modes of polymer degradation were considered, with mechanical (shear) degradation being of greatest concern. Appropriate use of near-wellbore fractures may mitigate mechanical degradation effectively, as well as improving injectivity.
Several new polymers show potential for cost-effective improvements at Daqing. Increased polymer concentration was also considered. A number of other approaches are (or have been) under investigation, including colloidal dispersion gels, foams, ASP foams, steam, microbes, and polymer solutions prepared with reduced salinity.
Introduction
Laboratory research began in the 1960s, investigating the potential of EOR processes in the Daqing oil field. The use of polymer flooding was identified as a key method to improve areal and vertical sweep efficiency, as well as providing mobility control (Wang 1995). Consequently, the world's largest polymer flood was implemented at Daqing, beginning in 1996 (Wankui et al. 2000, Wang et al. 2002). By 2004, 22.7% of total production from the Daqing oil field was attributed to polymer flooding. Polymer flooding should boost the ultimate recovery for the field to more than 50% of original oil in place (OOIP), which is 10% OOIP more than from waterflooding.
ASP flooding also has experienced extensive laboratory testing in China. The ASP technique was gradually perfected for application at Daqing and has been pilot tested on a large scale (Wang et al. 1999; Jirui et al. 2001; Wang 2003). Results from two typical pilot tests in the south and north parts of the Daqing field revealed incremental-oil-recovery values as high as 20% OOIP. By the end of 2003, the Center Xinger pilot site showed a definitive increase in oil production and decrease in water cut. In the east area of this site (the largest portion included within the ASP pattern area), the predicted EOR was approximately 18% OOIP more than from waterflooding.
Although field tests of polymer and ASP flooding have been very successful at Daqing, concerns about sweep efficiency persist—particularly the possibility of channeling expensive chemical formulations through the reservoir. Therefore, the sweep efficiency at Daqing is receiving intense scrutiny, and possibilities for improvement are being considered. In this paper, we examine the nature of reservoir sweep in parts of the Daqing oil field that have been EOR targets. We investigate the potential of various approaches for improving sweep. Our objective is to establish better options in the future for improving sweep in the main producing zone.
File Size | 2 MB | Number of Pages | 9 |
References
Chang, H.L. et al. 2006. Successful Field Pilot of In-DepthColloidal Dispersion Gel (CDG) Technology in Daqing Oil Field.SPEREE 9 (5): 664-673. SPE-89460-PA. DOI: 10.2118/89460-PA.
Cheng, J., Wang, D., Sui, X., Zeng, H., and Bai, W. 2006. Combining Small Well Spacing WithPolymer Flooding To Improve Oil Recovery of Marginal Reservoirs. Paper SPE96946 presented at the SPE Improved Oil Recovery Symposium, Tulsa, 22-26 April.DOI: 10.2118/96946-MS.
Crawford, F.B. and Collins, R.E. 1954. Estimated Effect of VerticalFractures on Secondary Recovery. Trans., AIME 201: 192-196.
Dyes, A.B., Kemp, C.E., and Caudle, B.H. 1958. Effect of Fractures onSweep-Out Pattern. Trans., AIME 213: 245-249.
Jirui, H., Zhongchun, Z., Xiang'an, Y., and Huifen, X. 2001. Study of the Effect of ASP SolutionViscoelasticity on Displacement Efficiency. Paper SPE 71492 presented atthe SPE Annual Technical Conference and Exhibition, New Orleans, 30 September-3October. DOI: 10.2118/71492-MS.
Knight, B.L. 1973. ReservoirStability of Polymer Solutions. JPT 25 (5): 618-626;Trans., SPE, 255. SPE-4167-PA. DOI: 10.2118/4167-PA.
Li, H., and Luo, P. 2001. Oil Displacement Evaluation of AqueousHydrophobically Associative Polymer Solution on Dykstra Parsons Cores forDaqing EOR. Oilfield Chemistry 18 (4): 338-341.
Luo, J., Pu, R., Wang, P., Bai, F., and Zhang, Y. 2002. PerformanceProperties of Salt Tolerant Polymer KYPAM for EOR. Oilfield Chemistry19 (1): 64-67.
Maitin, B.K. 1992. PerformanceAnalysis of Several Polyacrylamide Floods in North German Oil Fields. PaperSPE 24118 presented at the SPE/DOE Symposium on Enhanced Oil Recovery, Tulsa,22-24 April. DOI: 10.2118/24118-MS.
Moradi-Araghi, A. and Doe, P.H. 1984. Hydrolysis and Precipitation ofPolyacrylamides in Hard Brines at Elevated Temperatures. Paper SPE 13033presented at the SPE Annual Technical Conference and Exhibition, 16-19September, Houston. DOI: 10.2118/13033-MS.
Morris, C.W. and Jackson, K.M. 1978. Mechanical Degradation ofPolyacrylamide Solutions in Porous Media. Paper SPE 7064 presented at theSPE Symposium on Improved Methods of Oil Recovery, Tulsa, 16-17 April. DOI:10.2118/7064-MS.
Ryles, R.G. 1988. ChemicalStability Limits of Water-Soluble Polymers Used in Oil Recovery Processes.SPERE 3 (1): 23-34. SPE-13585-PA. DOI: 10.2118/13585-PA.
Seright, R.S. 1983. The Effectsof Mechanical Degradation and Viscoelastic Behavior on Injectivity ofPolyacrylamide Solutions. SPEJ 23 (3): 475-485. SPE-9297-PA.DOI: 10.2118/9297-PA.
Seright, R.S. 1988. Placementof Gels To Modify Injection Profiles. Paper SPE 17332 presented at the SPEEnhanced Oil Recovery Symposium, Tulsa, 16-21 April. DOI:10.2118/17332-MS.
Seright, R.S. 2005. Aperture-Tolerant, Chemical-Based Methods to ReduceChanneling. Annual Technical Progress Report, Contract No. DE-FC26-04NT15519,Washington, DC: US DOE, September.
Seright, R.S. 2007. Are Colloidal Dispersion Gels Really a ViableTechnology? And Designing Gel Treatments. http://baervan.nmt.edu/randy/.
Seright, R.S., Han, P., and Wang, D. 2006. Current Colloidal Dispersion GelsAre Not Superior to Polymer Flooding. Petroleum Geology & OilfieldDevelopment in Daqing 5 (5): 71-80.
Seright, R.S., Lane, R.H., and Sydansk, R.D. 2003. A Strategy for Attacking Excess WaterProduction. SPEPF 18 (3): 158-169. SPE-84966-PA. DOI:10.2118/84966-PA.
Shi, C., Du, Q., Zhu, L., et al. 2006. Research on Remaining OilDistribution and Further Development Methods for Different Kinds of Oil Layersin Daqing Oilfield at High-Water-Cut Stage. Paper SPE 101034 presented atthe SPE Asia Pacific Oil and Gas Conference and Exhibition, Adelaide,Australia, 11-13 September. DOI: 10.2118/101034-MS.
Shupe, R.D. 1981. ChemicalStability of Polyacrylamide Polymers. JPT 33 (8): 1513-1529.SPE-9299-PA. DOI: 10.2118/9299-PA.
Sorbie, K.S. and Seright, R.S. 1992. Gel Placement in HeterogeneousSystems With Crossflow. Paper SPE 24192 presented at the SPE/DOE EnhancedOil Recovery Symposium, Tulsa, 22-24 April. DOI: 10.2118/24192-MS.
Trantham, J.C., Threlkeld, C.B., and Patternson, H.L. 1980. Reservoir Description for aSurfactant/Polymer Pilot in a Fractured, Oil-Wet Reservoir—North Burbank UnitTract 97. JPT 32 (9): 1647-1656. SPE-8432-PA. DOI:10.2118/8432-PA.
Wang, D. 2003. Evaluation of Numerical Simulation Matching Study on the ASPField Tests in Daqing. International Symposium on Petroleum High EfficiencyExploit of Oil and Gas, Beijing, 29 September-1 October.
Wang, D. et al. 2001b. Successful Field Test of the FirstUltra-Low Interfacial Tension Foam Flood. Paper SPE 72147 presented at theSPE Asia Pacific Improved Oil Recovery Conference, Kuala Lumpur, 6-9 October.DOI: 10.2118/72147-MS.
Wang, D., Cheng, J., Junzheng, W., and Yan, W. 2002. Producing by Polymer Flooding MoreThan 300 Million Barrels of Oil, What Experiences Have Been Learnt? PaperSPE 77872 presented at the SPE Asia Pacific Oil and Gas Conference andExhibition, Melbourne, Australia, 8-10 October. DOI: 10.2118/77872-MS.
Wang, D., Cheng, J., Wu, J., et al. 1999. Summary of ASP Pilots in Daqing OilField. Paper SPE 57288 presented at the SPE Asia Pacific Improved OilRecovery Conference, Kuala Lumpur, 25-26 October. DOI: 10.2118/57288-MS.
Wang, D., Han, P., Shao, Z., Chen, J., and Seright, R.S. 2006. Sweep Improvement Options for theDaqing Oil Field. Paper SPE 99441 presented at the SPE/DOE Symposium onImproved Oil Recovery, Tulsa, 22-26 April. DOI: 10.2118/99441-MS.
Wang, D., Huifen, X., Zhongchun, L., and Qingyan, Y. 2001a. Study of the Mechanism of PolymerSolution With Visco-Elastic Behavior Increasing Microscopic Oil DisplacementEfficiency and the Forming of Steady "Oil Thread" Flow Channels. Paper SPE68723 presented at the SPE Asia Pacific Oil and Gas Conference and Exhibition,Jakarta, 17-19 April. DOI: 10.2118/68723-MS.
Wang, Y. and Luo, J. 2003. KYPAM Salt-Resistant Comb-Shape PolymerApplication in Oil Field. Chemical Industry and Engineering Progress22 (5): 509-511.
Wang, Z. 1995. Enhanced Oil Recovery Techniques and TheirApplication. Shanghai, China: Shanghai Transportation University.
Wankui, G. et al. 2000. Commercial Pilot Test of PolymerFlooding in Daqing Oil Field. Paper SPE 59275 presented at the SPE/DOESymposium on Enhanced Oil Recovery, Tulsa, 3-6 April. DOI:10.2118/59275-MS.
Wankui, G. et al. 2006. Microbe-Enhanced Oil RecoveryTechnology Obtains Huge Success in Low-Permeability Reservoirs in DaqingOilfield. Paper SPE 104281 presented at the SPE Eastern Regional Meeting,Canton, Ohio, 11-13 October. DOI: 10.2118/104281-MS.
Yang, F. et al. 2004. High Concentration Polymer Flooding Is Successful.Paper SPE 88454 presented at the SPE Asia Pacific Oil and Gas Conference andExhibition, Perth, Australia, 18-20 October. DOI: 10.2118/88454-MS.
Zhang, G. and Seright, R.S. 2007. Conformance and Mobility Control:Foams vs. Polymers. Paper SPE 105907 presented at the SPE InternationalSymposium on Oilfield Chemistry, Houston, 28 February- 2 March. DOI:10.2118/105907-MS.
Zhang, J. 1995. The EOR Technology. Beijing: Petroleum IndustryPublishing Company of China.