The Experts below are selected from a list of 39 Experts worldwide ranked by ideXlab platform
Malcolm Greaves - One of the best experts on this subject based on the ideXlab platform.
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effect of pre ignition heating cycle method air injection flux and reservoir viscosity on the thai heavy oil recovery process
Journal of Petroleum Science and Engineering, 2018Co-Authors: Malcolm Greaves, Sean P. RigbyAbstract:Abstract Heavy oil and bitumen reserves can potentially bridge the gap in world energy demand during the transition between conventional hydrocarbon fuels and sustainable energy sources, while the latter are developed. However, the development of efficient extraction methods with low emissions is necessary. The in-situ combustion process, toe-to-heel air injection (THAI), is such a method, but some issues remain in improving its performance. In this paper, the performance of the THAI process has been investigated at the laboratory scale using a validated simulation model. We have studied the effect of pre-ignition heating cycle (PIHC) method, reservoir oil viscosity, and air injection flux, on the stability and operability of the THAI process. It was found that the use of steam, instead of electrical heaters, for the PIHC resulted in an increase in oil recovery. However, use of steam also caused a reduction in oxygen utilisation. The use of a horizontal injector (HI) well, in combination with the steaming during the PIHC, causes some of the oxygen to bypass the combustion front during the early stage of air injection. It is concluded that steaming using a Staggered Line Drive, or 2VIHP well arrangement, is recommended to be used at the field scale. It was also found that THAI operates more stably for higher viscosity oil, albeit at higher operating cost, due to increased cumulative air-oil ratio (CAOR), compared to for a low oil viscosity reservoir. In contrast to previous suppositions, it has been found that oil recovery increases non-Linearly with an increase in air flux, which needs to be taken into account on scale-up.
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in situ upgrading of athabasca tar sand bitumen using thai
Chemical Engineering Research & Design, 2006Co-Authors: T X Xia, Malcolm GreavesAbstract:Downhole upgrading of virgin Athabasca Tar Sand bitumen has been investigated in a series of 3-D experiments using THAI—‘Toe-to-Heel Air Injection’. The THAI process uses combinations of vertical injection wells and horizontal producer wells, arranged in a direct, or Staggered Line Drive. 3-D experiments were performed to investigate THAI as a primary recovery method, and also as a secondary recovery method. The latter followed a prior THSF—‘Toe-to-Heel Steam Flood’. Oil recovery efficiencies for THAI, using primary and secondary operation modes, were respectively, 80% and 67% OOIP. The THSF recovery was much lower, only 23% OOIP, owing to the low steam temperature in the sandpack. Downhole upgrading of the Athabasca Tar Sand bitumen was very significant, with the API gravity of the produced oil increasing by an average of 8° API, compared to the original bitumen. The produced oil viscosity was also dramatically reduced, to less than 200 mPa s, with a minimum value of 50 mPa s. SARA analysis was used to assess the quality of the produced oil. The original bitumen contained only 15.5% saturates, but the amount in the produced oil was increased to 72%. The high oil recovery factor and partial in situ upgrading achieved by the THAI process could therefore have important economic implications for the future of heavy oil and bitumen production. The first field pilot of the THAI process is scheduled to take place at Christina Lake, Alberta, Canada, in 2006.
T X Xia - One of the best experts on this subject based on the ideXlab platform.
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in situ upgrading of athabasca tar sand bitumen using thai
Chemical Engineering Research & Design, 2006Co-Authors: T X Xia, Malcolm GreavesAbstract:Downhole upgrading of virgin Athabasca Tar Sand bitumen has been investigated in a series of 3-D experiments using THAI—‘Toe-to-Heel Air Injection’. The THAI process uses combinations of vertical injection wells and horizontal producer wells, arranged in a direct, or Staggered Line Drive. 3-D experiments were performed to investigate THAI as a primary recovery method, and also as a secondary recovery method. The latter followed a prior THSF—‘Toe-to-Heel Steam Flood’. Oil recovery efficiencies for THAI, using primary and secondary operation modes, were respectively, 80% and 67% OOIP. The THSF recovery was much lower, only 23% OOIP, owing to the low steam temperature in the sandpack. Downhole upgrading of the Athabasca Tar Sand bitumen was very significant, with the API gravity of the produced oil increasing by an average of 8° API, compared to the original bitumen. The produced oil viscosity was also dramatically reduced, to less than 200 mPa s, with a minimum value of 50 mPa s. SARA analysis was used to assess the quality of the produced oil. The original bitumen contained only 15.5% saturates, but the amount in the produced oil was increased to 72%. The high oil recovery factor and partial in situ upgrading achieved by the THAI process could therefore have important economic implications for the future of heavy oil and bitumen production. The first field pilot of the THAI process is scheduled to take place at Christina Lake, Alberta, Canada, in 2006.
Muhammad Rabiu Ado - One of the best experts on this subject based on the ideXlab platform.
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simulation study on the effect of reservoir bottom water on the performance of the thai in situ combustion technology for heavy oil tar sand upgrading and recovery
SN Applied Sciences, 2020Co-Authors: Muhammad Rabiu AdoAbstract:Some of the bitumen/tar sand/heavy oil reservoirs are underlain by bottom water (BW) layer, which often severely affects the performance of thermal EOR (enhanced oil recovery) processes. The effect of bottom water on the performance of the toe-to-heel air injection (THAI) in-situ combustion (ISC) process is investigated through reservoir simulation using CMG STARS simulator. The current study has shown that there is a limit to BW thickness above which the performance of the THAI process is affected even though the combustion front propagated stably. It is found that the thickness of the ‘‘basal gas layer’’ (BGL) depends on how further down into the BW zone the horizontal producer (HP) well is located. From this study, it is found that the critical BW thickness, when the THAI process is implemented in any heavy oil BW reservoir with the wells arranged in an SLD (Staggered Line Drive) pattern, should lie in the range of 50% OL (oil layer) < BW (bottom water) < 100% OL (oil layer). A comparative study between the active and non-active aquifers models shows that the same cumulative volume of water is produced and that over the 715 days of the process, only negligible amount of oil is produced from BWN (i.e. static aquifer model). It is found that in neither of the models does oxygen bypass the combustion front and as in the previous studies, both fronts are restricted to the upper part of the reservoir, within the oil zone. Therefore, it follows that even in the presence of active aquifer (i.e. BWA model), the THAI process still operates stably in terms of combustion front propagation and sustenance. For the combustion initiated at the oil–water (O–W) interface, it is found that controlled gravity override resulted in a high rate of advancement of combustion front at the top of the reservoir. The combustion is observed to not propagate along the BGL, rather, it propagates as though it is initiated at the top of the reservoir. It is shown that the BGL is only formed during the early period of air injection as the combustion gases could not reach the HP well without displacing the water to create initial gas flow pathway into the HP well. It is also observed that initiating the combustion at the oil–water interface results in a massively improved oil recovery rates, most especially when implemented in the DLD (direct Line Drive) pattern.
Robert A Hogarth - One of the best experts on this subject based on the ideXlab platform.
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simulation of the habanero enhanced geothermal system egs australia
2015Co-Authors: Ella Maria Llanos, Sadiq J. Zarrouk, Robert A HogarthAbstract:A TOUGH2 reservoir model has been developed for the Habanero EGS, located in the Cooper Basin. The reservoir, interpreted to be the sub-horizontal Habanero fault, was defined by the extent of the stimulated seismic cloud. A 1D natural state model was used first to calibrate the rock properties: specific heat capacity, thermal conductivity, heat generation and the heat flux at the base of the model. The temperature distribution was matched against measured down-hole data from well Habanero 1. A 3D model was then developed with 9 horizontal layers and aligned along an impermeable eastern boundary fault. Gravity potentially plays an important role so the model was tilted to the west-south-west. Since the fine 72,000 cell model only extends to 20 km 2 whilst the reservoir rock (Innamincka Granite) extends to over ~1,000 km 2 , Dirichlet boundary condition (large block volumes) was used for the sides with closed boundaries at the top and bottom. These large cells simulate the extension of the reservoir beyond the limited dimensions of the basic model. The permeability of the stimulated and mud damaged zones was calibrated using stable closed-loop (doublet) production and injection history data. The porosity was calibrated by simulating the two tracer tests carried out at Habanero. In preparing future production forecasts, three different well layouts were considered: Staggered Line Drive; inverted 4spot and regular 5-spot. For each scenario, closed-loop circulation was modelled for a production period of 20 years. For a largerscale development plan, recommendations to provide the best outcome, balancing short-term temperature against long-term extensibility are presented.
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numerical model of the habanero geothermal reservoir australia
Geothermics, 2015Co-Authors: Ella Maria Llanos, Sadiq J. Zarrouk, Robert A HogarthAbstract:Abstract A TOUGH2 reservoir model has been developed for the Habanero enhanced geothermal system (EGS), located in the Cooper Basin, Australia. The reservoir, interpreted to be the sub-horizontal Habanero fault, was defined by the extent of the stimulated seismic cloud. A 1D natural state model was used first to calibrate the rock thermal properties, heat generation and the heat flux at the base of the model. The temperature distribution was matched against measured down-hole data from well Habanero 1. A 3D model was then developed with 9 horizontal layers and aligned along an impermeable eastern boundary fault. Gravity potentially plays an important role so the model was tilted to the west-south-west. Since the fine 72,000 cell model only extends to 20 km2 whilst the reservoir rock (Innamincka Granite) extends to over ∼1000 km2, Dirichlet boundary condition (large block volumes) was used for the sides with closed boundaries at the top and bottom. These large cells simulate the extension of the reservoir beyond the limited dimensions of the basic model. The permeability of the stimulated and mud damaged zones was calibrated using stable closed-loop (doublet) production and injection history data. The porosity was calibrated by simulating the two tracer tests carried out at Habanero. In preparing future production forecasts, four different well layouts were considered: Staggered Line Drive (SLD); inverted 4-spot, regular 5-spot and east-west SLD. For each scenario, closed-loop circulation at 25, 35 and 45 kg/s per well was modeled for a production period of 20 years. The well patterns were stretched to about the maximum well separation available within the existing seismic cloud, as well as hypothetical seismic clouds. For a larger-scale development plan the best outcome was chosen by balancing short-term temperature against long-term extensibility. The results within the existing seismic cloud indicate the 4-spot layout as the most optimum. The best temperature performance is obtained from an extended seismic cloud when using an east-west SLD.
Ella Maria Llanos - One of the best experts on this subject based on the ideXlab platform.
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simulation of the habanero enhanced geothermal system egs australia
2015Co-Authors: Ella Maria Llanos, Sadiq J. Zarrouk, Robert A HogarthAbstract:A TOUGH2 reservoir model has been developed for the Habanero EGS, located in the Cooper Basin. The reservoir, interpreted to be the sub-horizontal Habanero fault, was defined by the extent of the stimulated seismic cloud. A 1D natural state model was used first to calibrate the rock properties: specific heat capacity, thermal conductivity, heat generation and the heat flux at the base of the model. The temperature distribution was matched against measured down-hole data from well Habanero 1. A 3D model was then developed with 9 horizontal layers and aligned along an impermeable eastern boundary fault. Gravity potentially plays an important role so the model was tilted to the west-south-west. Since the fine 72,000 cell model only extends to 20 km 2 whilst the reservoir rock (Innamincka Granite) extends to over ~1,000 km 2 , Dirichlet boundary condition (large block volumes) was used for the sides with closed boundaries at the top and bottom. These large cells simulate the extension of the reservoir beyond the limited dimensions of the basic model. The permeability of the stimulated and mud damaged zones was calibrated using stable closed-loop (doublet) production and injection history data. The porosity was calibrated by simulating the two tracer tests carried out at Habanero. In preparing future production forecasts, three different well layouts were considered: Staggered Line Drive; inverted 4spot and regular 5-spot. For each scenario, closed-loop circulation was modelled for a production period of 20 years. For a largerscale development plan, recommendations to provide the best outcome, balancing short-term temperature against long-term extensibility are presented.
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numerical model of the habanero geothermal reservoir australia
Geothermics, 2015Co-Authors: Ella Maria Llanos, Sadiq J. Zarrouk, Robert A HogarthAbstract:Abstract A TOUGH2 reservoir model has been developed for the Habanero enhanced geothermal system (EGS), located in the Cooper Basin, Australia. The reservoir, interpreted to be the sub-horizontal Habanero fault, was defined by the extent of the stimulated seismic cloud. A 1D natural state model was used first to calibrate the rock thermal properties, heat generation and the heat flux at the base of the model. The temperature distribution was matched against measured down-hole data from well Habanero 1. A 3D model was then developed with 9 horizontal layers and aligned along an impermeable eastern boundary fault. Gravity potentially plays an important role so the model was tilted to the west-south-west. Since the fine 72,000 cell model only extends to 20 km2 whilst the reservoir rock (Innamincka Granite) extends to over ∼1000 km2, Dirichlet boundary condition (large block volumes) was used for the sides with closed boundaries at the top and bottom. These large cells simulate the extension of the reservoir beyond the limited dimensions of the basic model. The permeability of the stimulated and mud damaged zones was calibrated using stable closed-loop (doublet) production and injection history data. The porosity was calibrated by simulating the two tracer tests carried out at Habanero. In preparing future production forecasts, four different well layouts were considered: Staggered Line Drive (SLD); inverted 4-spot, regular 5-spot and east-west SLD. For each scenario, closed-loop circulation at 25, 35 and 45 kg/s per well was modeled for a production period of 20 years. The well patterns were stretched to about the maximum well separation available within the existing seismic cloud, as well as hypothetical seismic clouds. For a larger-scale development plan the best outcome was chosen by balancing short-term temperature against long-term extensibility. The results within the existing seismic cloud indicate the 4-spot layout as the most optimum. The best temperature performance is obtained from an extended seismic cloud when using an east-west SLD.