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Ron C. K. Wong - One of the best experts on this subject based on the ideXlab platform.
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Surface Heave Induced by Steam Stimulation in Oil Sand Reservoirs
Journal of Canadian Petroleum Technology, 2008Co-Authors: Ron C. K. Wong, J. LauAbstract:Steam stimulation is one of the viable methods to extract heavy Oil from Oil Sand reservoirs in Alberta. In this thermal process, steam is injected into the Oil Sand reservoir. The Oil Sand fort}nation+@& to an increase in pore pressure and thermal heating. This expansion results in an upward movement of the overburden, and thus, heaving of the free ground surface. This paper proposes an analytical method to estimate the surface heave induced by steam injection. The method was used to investigate the surface heave profiles under horizontal well injection. It was found that the surface heave profile is governed by the mass and heat transfer and distribution within the Oil Sand reservoir. The effect of the increase in pore pressure (or decrease in net overburden stress) on the surface heave is also compared to that due to the thermal expansion of the Oil Sand. The paper also discusses the limitations on the use of surface heave monuments and tiltmeters in monitoring the thermal recovery process.
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Strain-induced anisotropy in fabric and hydraulic parameters of Oil Sand in triaxial compression
Canadian Geotechnical Journal, 2003Co-Authors: Ron C. K. WongAbstract:Dense locked Athabasca Oil Sand specimens were tested in drained triaxial compression with lubricated ends at confining pressures of 5750 kPa. Computer tomography and scanning electron microscopy imaging techniques were used to examine the microstructural features (interlocked structure, grain fabric, and rearrangement inside and outside shear bands) of the intact and sheared specimens. The average hydraulic radii and tortuosity along three principal directions were also measured using thin section imaging and electrical resistivity measurement methods. It was found that changes in fabric and hydraulic parameters of Oil Sand in triaxial compression are highly inter-related. Intrinsic and induced anisotropies in permeability were observed.Key words: Oil Sand, fabric, strain induced anisotropy, permeability, tortuosity, dilatancy.
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A Study of Flow Tortuosity in Locked Oil Sand
Canadian International Petroleum Conference, 2002Co-Authors: Ron C. K. Wong, R. MovassaghAbstract:Tortuosity factor exerts a major influence on fluid flow in porous medium. However, this factor is very difficult to quantify from experimental measuremehts, particularly in deformable medium. It is commonly treated as an empirical or curve-fitting parameter in determination of permeability. This study attempts to use the electrical resistivity measurement method as an analytical tool to study how changes in grain fabric affect changes in tortuosity. The first phase of the study concentrates on development of a framework on the flow tortuosity behaviour observed in idealized granular assemblies of regular packings with uniform spheres subjected to various types of grain fabric alteration, such as matrix dilation and grain rearrangement (rolling and overriding). Then, the framework is extended to interpret data measured in real random systems of intact and sheared Oil Sand specimens. It was found that the locked structure in intact Oil Sand specimens produce relatively high tortuosity factors as compared to those in the idealized packings. Shear deformation disrupts this intrinsic structure reducing the tortuosity factor to about one-fifth of the initial value. This peculiar behaviour implies that the permeability of Oil Sand is very sensitive to shear deformation or grain fabric alteration.
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Behaviour of water-jet mined caverns in Oil Sand and shale
Canadian Geotechnical Journal, 1996Co-Authors: Ron C. K. WongAbstract:Cavern of up to 10 m in diameter were mined in Oil Sand and shale formations at depths of 500 m in Cold Lake, Alberta. The cavens were subjected to high-pressure water jetting, pumping bitumenSand slurry to the surface, cyclic water pressurization and depressurization, and gas exsolution. Roof and wall shapes were monitored by sonar logs. Numerical models are proposed to explain the roof and wall sloughing mechanisms in Oil Sand and shale. Key words: Oil Sand, shale, cavern, water jetting, collapse mechanism.
R.c.k. Wong - One of the best experts on this subject based on the ideXlab platform.
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strain dependent creep behavior of athabasca Oil Sand in triaxial compression
International Journal of Geomechanics, 2017Co-Authors: Zhechao Wang, R.c.k. WongAbstract:AbstractOil Sand is a dense granular material with interlocking fabric. As a strain-softening material, Oil Sand exhibits a more complex creep behavior than that of strain-hardening geomaterials. The creep behavior of Oil Sand could be excessive and detrimental to surface and subsurface facilities in the long term. This paper describes a study on creep behavior of Oil Sands. A series of triaxial compression creep tests were performed on Oil Sand to investigate its creep behavior at different stress and strain levels. The creep behavior of Oil Sand is dependent not only on both time and stress but also on initial inelastic strain, and it is influenced by the growth of shear bands. A strain-dependent creep model was proposed to describe the prepeak creep behavior of the Oil Sand. With this model, the dependence of creep rate of Oil Sands on time, stress, and strain is taken into consideration properly. It was argued that the change in the microstructure of Oil Sand could be uniquely represented by the inela...
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Shaft resistance of bored cast-in-place concrete piles in Oil Sand - Case study
Geomechanics and Engineering, 2013Co-Authors: L. Barr, R.c.k. WongAbstract:Pile load tests using Osterberg cells (O-cell) were conducted on cast-in-place concrete piles founded in Oil Sand fill and in situ Oil Sand at an industrial plant site in Fort McMurray, Alberta, Canada. Interpreted pile test results show that very high pile shaft resistance (with the Bjerrum-Burland or Beta coefficient of 2.5-4.5) against Oil Sand could be mobilized at small relative displacements of 2-3% of shaft diameter. Finite element simulations based on linear elastic and elasto-plastic models for Oil Sand materials were used to analyze the pile load test measurements. Two constitutive models yield comparable top-down load versus pile head displacement curves, but very different behaviour in mobilization of pile shaft and end bearing resistances. The elasto-plastic model produces more consistent matching in both pile shaft and end bearing resistances whereas the linear elastic under- and over-predicts the shaft and end bearing resistances, respectively. The mobilization of high shaft resistance in Oil Sand under pile load is attributed to the very dense and interlocked structure of Oil Sand which results in high matrix stiffness, high friction angle, and high shear dilation.
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Surface Heave Induced by Steam Stimulation in Oil Sand Reservoirs
Journal of Canadian Petroleum Technology, 2008Co-Authors: R.c.k. Wong, J. LauAbstract:Abstract Steam stimulation is one of the viable methods to extract heavy Oil from Oil Sand reservoirs in Alberta. In this thermal process, steam is injected into the Oil Sand reservoir. The Oil Sand formation expands due to an increase in pore pressure and thermal heating. This expansion results in an upward movement of the overburden, and thus, heaving of the free ground surface. This paper proposes an analytical method to estimate the surface heave induced by steam injection. The method was used to investigate the surface heave profiles under horizontal well injection. It was found that the surface heave profile is governed by the mass and heat transfer and distribution within the Oil Sand reservoir. The effect of the increase in pore pressure (or decrease in net overburden stress) on the surface heave is also compared to that due to the thermal expansion of the Oil Sand. The paper also discusses the limitations on the use of surface heave monuments and tiltmeters in monitoring the thermal recovery process. Introduction Thermal recovery processes such as cyclic steam stimulation (CSS) and steam assisted gravity drainage (SAGD) involve large volume fluid and steam injection into Oil Sand reservoirs. Steam injection produces a dilatation of the Oil Sand reservoir due to an increase in pore pressure and temperature of the reservoir. The overburden containing the reservoir responds to the steam injection by upward heaving of the free ground surface. Surface heave of up to 20 cm has been recorded(1). The profile of the surface heave reflects the distribution of the injected steam within the Oil Sand formation. Monitoring the surface heave evolution during the steaming operation may be used as an inverse method of monitoring the steam injection operation. This paper presents an analytical method to determine the surface heave profile induced by steam stimulation for a horizontal well. Parametric studies were conducted to investigate the important factors contributing to the surface heave profile. Problem Statement This study considers a steam stimulation operation using a horizontal well. Steam is injected into a horizontal well installed within an Oil Sand formation of finite thickness (Figure 1). Since the overburden serves as a competent hydraulic barrier to the fluid upward migration, it is assumed that the injected steam is contained within the Oil Sand reservoir, which results in an expansion of the reservoir. Thus, steam injection using a horizontal well can be treated as a two-dimensional plane strain problem. Figure 1 illustrates the problem statement. The objective of the exercise is to determine the surface heave profile as a function of the amount of steam injected into the horizontal well. Methodology Steam stimulation is a complex thermal hydraulic mechanical multiphase flow process. Determination of injected fluid distribution within the reservoir is not trivial. Since the shale overburden serves as a competent hydraulic barrier to the fluid upward migration, the geomechanical responses in the overburden are governed by the expansion pattern of the Oil Sand reservoir due to steam stimulation.
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A Study of Flow Tortuosity in Locked Oil Sand
Journal of Canadian Petroleum Technology, 2004Co-Authors: R.c.k. Wong, R. MovssaghAbstract:Abstract Tortuosity factor exerts a major influence on fluid flow in porous medium. However, this factor is very difficult to quantify from experimental measurements, particularly in deformable medium. It is commonly treated as an empirical or curve-fitting parameter in determination of permeability. This study attempts to use the electrical resistivity measurement method as an analytical tool to study how changes in grain fabric affect changes in tortuosity. The first phase of the study concentrates on development of a framework on the flow tortuosity behaviour observed in idealized granular assemblies of regular packings with uniform spheres subjected to various types of grain fabric alteration, such as matrix dilation and grain rearrangement (rolling and overriding). Then, the framework is extended to interpret data measured in real random systems of intact and sheared Oil Sand specimens. It was found that the locked structure in intact Oil Sand specimens produce relatively high tortuosity factors as compared to those in the idealized packings. Shear deformation disrupts this intrinsic structure reducing the tortuosity factor to about one-fifth of the initial value. This peculiar behaviour implies that the permeability of Oil Sand is very sensitive to shear deformation or grain fabric alteration. Introduction The Athabasca Oil Sand deposit in northern Alberta, Canada, contains 200 billion m3 of bitumen in place(1). Oil Sand is a very dense granular material with interlocked fabric(2, 3). The main mineral composition is dominated by quartz. Its in situ porosity varies from 30 to 35%, whereas its maximum porosity can be as high as 45 to 47%. Viscous bitumen filling the intergranular spaces does not affect the geotechnical properties of the material. Steam stimulation is one of the viable methods used to extract bitumen from the Oil Sand ore. Large volumes of steam of a high pressures (up to 10 MPa) and at elevated temperatures (up to 300 ° C) are injected into Oil Sand reservoirs. Because Oil Sands are dense uncemented Sands, the resulting deformation induced during the recovery processes could cause significant changes in its hydraulic properties. The understanding of its hydraulic properties due to shear deformation is important for the design of the steam stimulation recovery processes. Wong et al.(3) conducted pulse-decay tests to determine changes in absolute and effective permeabilities (to water) of Oil Sand under conventional triaxial compression. Touhidi-Baghini(4) sed the constant flow rate method to quantify changes in absolute permeability of locked Sands specimens under triaxial compressions along various stress paths. They observed that volumetric dilation in triaxial compression could be as high as up to 10% and the permeability could be increased by five to six times even though localized multiple shear bands were developed in the specimens. In these conventional permeability tests, the measured hydraulic properties are average responses of the test specimens subject to test boundary conditions, and are significantly influenced by the formation of localized shear bands. They are no longer unique, and become dependent on specimen dimension and test conditions.
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The hydraulic and mechanical response of an Oil Sand fracture under a varying confining pressure
Canadian Geotechnical Journal, 1999Co-Authors: D. A. Walters, R.c.k. WongAbstract:An experimental study was conducted to investigate the effect of the variable-aperture system of an Oil Sand fracture on its hydraulic and mechanical response to an increasing confining pressure. The Oil Sand fracture was induced in core samples along the axis of the sample using the Brazilian tensile test. A computer-assisted tomography (CT) scanning analysis was performed to determine the initial fracture geometry and monitor the closure process. The fracture was shown to be a variable-aperture system, with surface roughness and tortuosity playing an increasing role as the fracture closed under pressure. Flow tests revealed a nonlinear behaviour, deviating from the cubic law, and indicated the roughness effects of a natural Oil Sand fracture are significant. The mechanical response was similar to that of the hydraulic behaviour, indicating the strong relationship between the two. The nature of the uncemented Oil Sand was shown to strongly affect the strength of the fracture contacts and, therefore, the ...
J. Lau - One of the best experts on this subject based on the ideXlab platform.
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Surface Heave Induced by Steam Stimulation in Oil Sand Reservoirs
Journal of Canadian Petroleum Technology, 2008Co-Authors: Ron C. K. Wong, J. LauAbstract:Steam stimulation is one of the viable methods to extract heavy Oil from Oil Sand reservoirs in Alberta. In this thermal process, steam is injected into the Oil Sand reservoir. The Oil Sand fort}nation+@& to an increase in pore pressure and thermal heating. This expansion results in an upward movement of the overburden, and thus, heaving of the free ground surface. This paper proposes an analytical method to estimate the surface heave induced by steam injection. The method was used to investigate the surface heave profiles under horizontal well injection. It was found that the surface heave profile is governed by the mass and heat transfer and distribution within the Oil Sand reservoir. The effect of the increase in pore pressure (or decrease in net overburden stress) on the surface heave is also compared to that due to the thermal expansion of the Oil Sand. The paper also discusses the limitations on the use of surface heave monuments and tiltmeters in monitoring the thermal recovery process.
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Surface Heave Induced by Steam Stimulation in Oil Sand Reservoirs
Journal of Canadian Petroleum Technology, 2008Co-Authors: R.c.k. Wong, J. LauAbstract:Abstract Steam stimulation is one of the viable methods to extract heavy Oil from Oil Sand reservoirs in Alberta. In this thermal process, steam is injected into the Oil Sand reservoir. The Oil Sand formation expands due to an increase in pore pressure and thermal heating. This expansion results in an upward movement of the overburden, and thus, heaving of the free ground surface. This paper proposes an analytical method to estimate the surface heave induced by steam injection. The method was used to investigate the surface heave profiles under horizontal well injection. It was found that the surface heave profile is governed by the mass and heat transfer and distribution within the Oil Sand reservoir. The effect of the increase in pore pressure (or decrease in net overburden stress) on the surface heave is also compared to that due to the thermal expansion of the Oil Sand. The paper also discusses the limitations on the use of surface heave monuments and tiltmeters in monitoring the thermal recovery process. Introduction Thermal recovery processes such as cyclic steam stimulation (CSS) and steam assisted gravity drainage (SAGD) involve large volume fluid and steam injection into Oil Sand reservoirs. Steam injection produces a dilatation of the Oil Sand reservoir due to an increase in pore pressure and temperature of the reservoir. The overburden containing the reservoir responds to the steam injection by upward heaving of the free ground surface. Surface heave of up to 20 cm has been recorded(1). The profile of the surface heave reflects the distribution of the injected steam within the Oil Sand formation. Monitoring the surface heave evolution during the steaming operation may be used as an inverse method of monitoring the steam injection operation. This paper presents an analytical method to determine the surface heave profile induced by steam stimulation for a horizontal well. Parametric studies were conducted to investigate the important factors contributing to the surface heave profile. Problem Statement This study considers a steam stimulation operation using a horizontal well. Steam is injected into a horizontal well installed within an Oil Sand formation of finite thickness (Figure 1). Since the overburden serves as a competent hydraulic barrier to the fluid upward migration, it is assumed that the injected steam is contained within the Oil Sand reservoir, which results in an expansion of the reservoir. Thus, steam injection using a horizontal well can be treated as a two-dimensional plane strain problem. Figure 1 illustrates the problem statement. The objective of the exercise is to determine the surface heave profile as a function of the amount of steam injected into the horizontal well. Methodology Steam stimulation is a complex thermal hydraulic mechanical multiphase flow process. Determination of injected fluid distribution within the reservoir is not trivial. Since the shale overburden serves as a competent hydraulic barrier to the fluid upward migration, the geomechanical responses in the overburden are governed by the expansion pattern of the Oil Sand reservoir due to steam stimulation.
Zhou Yan - One of the best experts on this subject based on the ideXlab platform.
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Experimental study on separation of flotation technology of Oil Sand
The Chemical Engineer, 2014Co-Authors: Zhou YanAbstract:With the increasing depletion of conventional energy sources, the separation technology of Oil Sand is attracting attention by the majority of researchers. The flotation technology is applied in separating the hydra type Oil Sand in Inner Mongolia. The results showed that the optimum conditions of flotation technology of Oil Sands are respectively concentration of NaOH 0.5%, temperature 50℃, Sand ratio 1.5, and the flotation efficiency can reach 98.1023%.
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Experimental study on separating agents of Oil Sand
The Chemical Engineer, 2013Co-Authors: Zhou YanAbstract:With the rising of the international Oil prices, the separation technology of the Oil Sand has aroused the attention of the majority of scholars. Oil Sand is a kind of non conventional energy, In this thesis, the study on separating agents of Oil Sand has been accomplished. The Oil Sand coming from Inner Mongolia is the type of moisture. It gives the self-made FLJ can enhance 3.37 percentage points of the washing Oil ratio. There is 3% volume shale Oil in the self-made FLJ. The bOiling point of shale Oil lower than 350℃.
Ki Bong Lee - One of the best experts on this subject based on the ideXlab platform.
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Kinetic study on the nonisothermal pyrolysis of Oil Sand bitumen and its maltene and asphaltene fractions
Journal of Analytical and Applied Pyrolysis, 2017Co-Authors: Sangcheol Shin, Eun Hee Kwon, Nam Sun Nho, Ki Bong LeeAbstract:Abstract Pyrolysis is an important conversion process which can produce high value-added light Oils from unconventional Oils such as Oil Sand bitumen and extra heavy Oil, thus it is important to understand the characteristics and kinetics of pyrolysis for unconventional Oils. In this study, the nonisothermal pyrolysis of Athabasca Oil Sand bitumen and its maltene and asphaltene fractions was analyzed using a thermogravimetric analyzer, and activation energies for pyrolysis were determined by the model-free isoconversional Friedman analysis. The analysis suggests that the pyrolysis of Oil Sand bitumen consists of reactions for volatilization of maltene fraction and cracking of maltene and asphaltene fractions. The pyrolysis behavior of Oil Sand bitumen was well described based on the kinetic parameters estimated by the distributed activation energy model for maltene and asphaltene fractions, which is beneficial to effective utilization and development of pyrolysis processes of Oil Sand bitumen.
