Study of Enhanced-Oil-Recovery Mechanism of Alkali/Surfactant/Polymer Flooding in Porous Media From Experiments
- Pingping Shen (Res. Inst. Petr. E&D, PetroChina) | Jialu Wang (Res. Inst. Petr. E&D, PetroChina) | Shiyi Yuan (PetroChina) | Taixian Zhong (PetroChina) | Xu Jia (Res. Inst. Petr. E&D, PetroChina)
- Document ID
- Society of Petroleum Engineers
- SPE Journal
- Publication Date
- June 2009
- Document Type
- Journal Paper
- 237 - 244
- 2009. Society of Petroleum Engineers
- 4.3.4 Scale, 4.1.2 Separation and Treating, 5.3.2 Multiphase Flow, 5.4.7 Chemical Flooding Methods (e.g., Polymer, Solvent, Nitrogen, Immiscible CO2, Surfactant, Vapex), 2.4.3 Sand/Solids Control, 5.3.1 Flow in Porous Media, 5.7.2 Recovery Factors, 5.4.1 Waterflooding, 2.5.2 Fracturing Materials (Fluids, Proppant), 4.1.5 Processing Equipment, 1.2.3 Rock properties
- 7 in the last 30 days
- 3,309 since 2007
- Show more detail
- View rights & permissions
|SPE Member Price:||USD 5.00|
|SPE Non-Member Price:||USD 35.00|
The fluid-flow mechanism of enhanced oil recovery (EOR) in porous media by alkali/surfactant/polymer (ASP) flooding is investigated by measuring the production performance, pressure, and saturation distributions through the installed differential-pressure transducers and saturation-measurement probes in a physical model of a vertical heterogeneous reservoir. The fluid-flow variation in the reservoir is one of the main mechanisms of EOR of ASP flooding, and the nonlinear coupling and interaction between pressure and saturation fields results in the fluid-flow variation in the reservoir. In the vertical heterogeneous reservoir, the ASP agents flow initially in the high-permeability layer. Later, the flow direction changes toward the low- and middle-permeability layers because the resistance in the high-permeability layer increases on physical and chemical reactions such as adsorption, retention, and emulsion. ASP flooding displaces not only the residual oil in the high-permeability layer but also the remaining oil in the low- and middle-permeability layers by increasing both swept volume and displacement efficiency.
Currently, most oil fields in China are in the later production period and the water cut increases rapidly, even to more than 80%. Waterflooding no longer meets the demands of oilfield production. Thus, it is inevitable that a new technology will replace waterflooding. The new technique of ASP flooding has been developed on the basis of alkali-, surfactant-, and polymer-flooding research in the late 1980s. ASP flooding uses the benefits of the three flooding methods simultaneously, and oil recovery is greatly enhanced by decreasing interfacial tension (IFT), increasing the capillary number, enhancing microscopic displacing efficiency, improving the mobility ratio, and increasing macroscopic sweeping efficiency (Shen and Yu 2002; Wang et al. 2000; Wang et al. 2002; Sui et al. 2000).
Recently, much intensive research has been done on ASP flooding both in China and worldwide, achieving some important accomplishments that lay a solid foundation for the extension of this technique to practical application in oil fields (Baviere et al. 1995; Thomas 2005; Yang et al. 2003; Li et al. 2003). In previous work, the ASP-flooding mechanism was studied visually by using a microscopic-scale model and double-pane glass models with sand (Liu et al. 2003; Zhang 1991). In these experiments, the water-viscosity finger, the residual-oil distribution after waterflooding, and the oil bank formed by microscopic emulsion flooding were observed. In Tong et al. (1998) and Guo (1990), deformation, threading, emulsion (oil/water), and strapping were observed as the main mechanisms of ASP flooding in a water-wetting reservoir, while the interface-producing emulsion (oil/water), bridging between inner pore and outer pore, is the main mechanism of ASP flooding in an oil-wetting reservoir. For a vertical heterogeneous reservoir, ASP flooding increases displacement efficiency by displacing residual oil through decreased IFT, simultaneously improving sweep efficiency by extending the swept area in both vertical and horizontal directions. Some physical and chemical phenomena, such as emulsion, scale deposition, and chromatographic separation, occur during ASP flooding (Arihara et al. 1999; Guo 1999). Because ASP flooding in porous media involves many complicated physicochemical properties, many oil-recovery mechanisms still need to be investigated.
Most research has been performed on the microscopic displacement mechanism of ASP flooding, while the fluid-flow mechanism in porous media at the macroscopic scale lacks sufficient study. In this paper, a vertical-heterogeneous-reservoir model is established, and differential-pressure transducers and saturation-measuring probes are installed. The fluid-flow mechanism of increasing both macroscopic sweep efficiency and microscopic displacement efficiency is studied by measuring the production performance and the variation of pressure and saturation distributions in the ASP-flooding experiment. An experimental database of ASP flooding also is set up and provides an experimental base for numerical simulation.
|File Size||1 MB||Number of Pages||8|
Arihara, N., Yoneyama, T., Akita, Y., and XiangGuo, L. 1999. Oil Recovery Mechanisms ofAlkali-Surfactant-Polymer Flooding. Paper SPE 54330 presented at the SPEAsia Pacific Oil and Gas Conference and Exhibition, Jakarta, 20-22 April. doi:10.2118/54330-MS.
Baviere, M., Glenat, P., Plazanet, V., and Labrid, J. 1995. Improved EOR by Use of Chemicals inCombination. SPE Res Eng 10 (3): 187-193. SPE-27821-PA.doi: 10.2118/27821-PA.
Guo, S. 1990. Physical Chemical Fluid Flow in Porous Media: MicroscopicMechanism. Beijing: Science Press.
Guo, W. 1999. Status and development direction of tertiary oil recoverytechnique in Daqing Oilfield. Petroleum Geology and Production of DaqingOilfield 18 (3): 24-26.
Li, H., Liao, G., Han, H., et al. 2003. Alkaline/Surfactant/Polymer(ASP)Commercial Flooding Test in Central Xing 2 Area of Daqing Oilfield. PaperSPE 84896 presented at the SPE International Improved Oil Recovery Conferencein Asia Pacific, Kuala Lumpur, 20-21 October. doi: 10.2118/84896-MS.
Liu, W., Li, L., Tong, Z., et al.. 2003. Microscopic Permeability Mechanismof ASP Flooding of Daqing Oilfield. Transactions of Chongqing University(Natural Science) 23 (1): 119-121.
Shen, P., and Yu, J., 2002. Fundamental research on enhanced oil recoveryin large scale. Beijing: Petroleum Industry Publication Company.
Shen, P., Wang, J., et al. 2002. Research of physical modeling andsimilarity theory of complex displacing system. Summary report of nationalfundamental key research project.
Sui, J., Yang, C.-Z., Yang, Z.-Y., et al. 2000. Surfactant-Alkaline-Polymer FloodingPilot Project in Non-Acidic Paraffin Oil Field in Daqing. Paper SPE 64509presented at the SPE Asia Pacific Oil and Gas Conference and Exhibition,Brisbane, Australia, 16-18 October. doi: 10.2118/64509-MS.
Thomas, S. 2005. Chemical EOR: The Past--Does It Have a Future? Paper SPE 108828presented as an SPE Distinguished Lecture, 2005-06.
Tong, Z., Yang, C., Wu, G., Yuan, H., Yu, L., and Tian, G. 1998. A Study of Microscopic FloodingMechanism of Surfacant/Alkali/Polymer. Paper SPE 39662 presented at theSPE/DOE Improved Oil Recovery Symposium, Tulsa, 19-22 April. doi:10.2118/39662-MS.
Wang, D., Cheng. J., Li, Q., Jiang, Y., Sun, Y., and He, Y., 2000. Experience of IOR Practices fromLarge-Scale Implementation in Layered Sandstones. Paper SPE 64287 presentedat the SPE Asia Pacific Oil and Gas Conference and Exhibition, Brisbane,Australia, 16-18 October. doi: 10.2118/64287-MS.
Wang, D., Sun, Y., Wang, Y., and Tang, X. 2002. Producing More Than 75% of Daqing OilField's Production by IOR, What Experiences Have Been Learnt? Paper SPE77871 presented at the SPE Asia Pacific Oil and Gas Conference and Exhibition,Melbourne, Australia, 8-10 October. doi: 10.2118/77871-MS.
Wang, J., and Shen, P. Saturation measuring method and measuring probe.China Patent No. ZL 01123944.1.
Yang, X.M., Liao, G., Han, P., Yang, Z., and Yao, Y. 2003. An Extended Field Test Study onAlkaline-Surfactant-Polymer Flooding in Beiyiduanxi of Daqing Oilfield.Paper SPE 80532 presented at the SPE Asia Pacific Oil and Gas Conference andExhibition, Jakarta, 9-11 September. doi: 10.2118/80532-MS.
Zhang Jingcun. 1991. Study of enhanced oil recovery. Beijing:Petroleum Industry Publication Company.