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A fast method for evaluating a simplified hot dry rock heat flow problem

Description: I present optimizations to the computation of Elsworth's single zone, hot dry rock thermal recovery model. These enhancements lead to as much as a 6-fold increase in computational speed. The greatest time savings derive from an efficient evaluation of the model's thermal response due to a step in heat flux, which is required for solution of the more general problem via Duhamel's Principle. Further enhancements come from taking advantage of the special structure of the model's finite difference equation. Reductions in execution speed were sought in order to facilitate the model's implementation on AT-class microcomputers. The PC-based application requires multiple evaluations of the model. Typical execution times on a 33 MHz 80386 microcomputer for 128 time steps were 7 seconds, as compared with 25-42 seconds for the non-optimized approach, and for 512 time steps were 28 and 100-168 seconds, respectively; the timing of the non-optimized method depended upon particulars of the dimensionless variables.
Date: January 1, 1992
Creator: Adair, R.G.
Partner: UNT Libraries Government Documents Department

Reactivation of an idle lease to increase heavy oil recovery through application of conventional steam drive technology in a low dip slope and basin reservoir in the Midway-Sunset Field, San Jaoquin Basin, California

Description: This project reactivates ARCO`s idle Pru Fee lease in the Midway- Sunset field, California and conducts a continuous steamflood enhanced oil recovery demonstration aided by an integration of modern reservoir characterization and simulation methods. Cyclic steaming is being used to reestablish baseline production within the reservoir characterization phase of the project. During the demonstration phase scheduled to begin in January 1997, a continuous steamflood enhanced oil recovery will be initiated to test the incremental value of this method as an alternative to cyclic steaming. Other economically marginal Class III reservoirs having similar producibility problems will benefit from insight gained in this project. The objectives of the project are: (1) to return the shut-in portion of the reservoir to optimal commercial production; (2) to accurately describe the reservoir and recovery process; and (3) to convey the details of this activity to the domestic petroleum industry, especially to other producers in California, through an aggressive technology transfer program. One of the main objectives of Budget Period I was to return the Pru Fee property to economic production and establish a baseline productivity with cyclic steaming. By the end of the second quarter 1996, all Pru producers except well 101 had been cyclic steamed two times. Each steam cycle was around 10,000 barrels of steam (BS) per well. No mechanical problems were found in the existing old wellbores. Conclusion is after several years of being shut-in, the existing producers on the Pru lease are in reasonable mechanical condition, and can therefore be utilized as viable producers in whatever development plan we determine is optimum. Production response to cyclic steam is very encouraging in the new producer, however productivity in the old producers appears to be limited in comparison.
Date: November 1, 1996
Creator: Schamel, S.
Partner: UNT Libraries Government Documents Department

Non-Adiabatic Effects on Combustion Front Propagation in Porous Media: Multiplicity of Steady States

Description: The sustained propagation of combustion fronts in porous media is a necessary condition for the success of an in situ combustion project for oil recovery. Compared to other recovery methods, in situ combustion involves the added complexity of exothermic reactions and temperature-dependent chemical kinetics. In the presence of heat losses, the possibility of ignition and extinction (quenching) exists. In this report, we address the properties of combustion fronts propagating at a constant velocity in the presence of heat losses.
Date: March 11, 2002
Creator: Akkutlu, I. Yucel & Yortsos, Yanis C.
Partner: UNT Libraries Government Documents Department

Thermal recovery of the NIF amplifiers

Description: With approximately 99% of the electrical energy supplied to the National Ignition Facility (NIF) appearing as heat in the amplifiers, thermal recovery of the NIF system is a major consideration in the design process. The NIF shot rate is one shot every 8 hours, with a goal of 4 hours between shots. This necessitates that thermal recovery take place in no more than 7 hours, with a goal of 3 hours for the accelerated shot rate. Residual optical distortions, which restrict the shot rate, are grouped into two discrete categories: (1) distortions associated with residual temperature gradients in the laser slabs, and (2) distortions associated with buoyantly driven convective currents in the amplifier cavity and beam-tube regions. Thermal recovery of the amplifiers is achieved by cooling the flashlamps and blastshields with a turbulent gas flow. The cooled blastshields then serve as a cold boundary to radiatively extract the residual heat deposited in the slabs and edge claddings. Advanced concepts, such as the use of slightly chilled gas to accelerate some aspects of recovery, are addressed. To quantify recovery rates of the amplifiers, experiments and numerical models are used to measure and calculate the temperatures and optical distortions in NIF-like amplifier elements. The calculation results are benchmarked against AMLAB temperature measurements, thus allowing a quantitative prediction of NIF thermal recovery. These results indicate that the NIF requirement of 7 hour thermal recovery can be achieved with chilled temperature cooling gas.
Date: June 30, 1998
Creator: Beullier, J; Bicrel,; Erlandson, A; London, R; Manes, K; Marshall, C et al.
Partner: UNT Libraries Government Documents Department

A Numerical Analysis of the Single-Well Steam Assisted Gravity Drainage (SW-SAGD) Process, SUPRI TR-124

Description: Results from this study include cumulative recoveries, temperature distributions, and production rates. It was found that cyclic steaming of the reservoir offers the most favorable option for heating the near-wellbore area to create conditions that improve initial SAGD response. More favorable reservoir conditions such as low viscosity, thick oil zones, and solution gas, improved reservoir response. Under unfavorable conditions, response was limited.
Date: July 23, 2001
Creator: Elliot, K.T. & Kovscek, A.R.
Partner: UNT Libraries Government Documents Department

Venezuela-MEM/USA-DOE Fossil Energy Report IV-11: Supporting technology for enhanced oil recovery - EOR thermal processes

Description: This report contains the results of efforts under the six tasks of the Tenth Amendment anti Extension of Annex IV, Enhanced Oil Recovery Thermal Processes of the Venezuela/USA Energy Agreement. This report is presented in sections (for each of the six Tasks) and each section contains one or more reports that were prepared to describe the results of the effort under each of the Tasks. A statement of each Task, taken from the Agreement Between Project Managers, is presented on the first page of each section. The Tasks are numbered 68 through 73. The first through tenth report on research performed under Annex IV Venezuela MEM/USA-DOE Fossil Energy Report Number IV-1, IV-2, IV-3, IV-4, IV-5, IV-6, IV-7, IV-8, IV-9, IV-10 contain the results of the first 67 Tasks. These reports are dated April 1983, August 1984, March 1986, July 1987, November 1988, December 1989, October 1991, February 1993, March 1995, and December 1997, respectively.
Date: April 6, 2000
Creator: Venezuela
Partner: UNT Libraries Government Documents Department

Strategies for gas production from hydrate accumulations under various geologic conditions

Description: In this paper we classify hydrate deposits in three classes according to their geologic and reservoir conditions, and discuss the corresponding production strategies. Simple depressurization appears promising in Class 1 hydrates, but its appeal decreases in Class 2 and Class 3 hydrates. The most promising production strategy in Class 2 hydrates involves combinations of depressurization and thermal stimulation, and is clearly enhanced by multi-well production-injection systems. The effectiveness of simple depressurization in Class 3 hydrates is limited, and thermal stimulation (alone or in combination with depressurization) through single well systems seems to be the strategy of choice in such deposits.
Date: April 29, 2003
Creator: Moridis, G. & Collett, T.
Partner: UNT Libraries Government Documents Department

Reactivation of an Idle Lease to Increase Heavy Oil Recovery through Application of Conventional Steam Drive Technology in a Low-Dip Slope and Reservoir in the Midway-Sunset Field, San Jaoquin Basin, California, Class III

Description: The objective of the project is not just to commercially produce oil from the Pru Fee property, but rather to test which operational strategies best optimize total oil recovery at economically acceptable rates of production volumes and costs.
Date: February 21, 2002
Creator: Schamel, Steven; Deo, Milind & Deets, Mike
Partner: UNT Libraries Government Documents Department

Transport and Phase Equilibria Properties for Steam Flooding of Heavy Oils

Description: The objectives of this research included experimental determination and rigorous modeling and computation of phase equilibrium diagrams, volumetric, and transport properties of hydrocarbon/CO2/water mixtures at pressures and temperatures typical of steam injection processes for thermal recovery of heavy oils.
Date: November 20, 2002
Creator: Gabitto, Jorge & Barrufet, Maria
Partner: UNT Libraries Government Documents Department

Experimental and Theoretical Determination of Heavy Oil Viscosity Under Reservoir Conditions

Description: The main objective of this research was to propose a simple procedure to predict heavy oil viscosity at reservoir conditions as a function of easily determined physical properties. This procedure will avoid costly experimental testing and reduce uncertainty in designing thermal recovery processes.
Date: March 11, 2002
Creator: Gabitto, Jorge & Barrufet, Maria
Partner: UNT Libraries Government Documents Department

Transport and Phase Equilibria Properties for Steam Flooding of Heavy Oils

Description: The objectives of this research included experimental determination and rigorous modeling and computation of phase equilibrium diagrams, volumetric, and transport properties of hydrocarbon/CO2/water mixtures at pressures and temperatures typical of steam injection processes for thermal recovery of heavy oils.
Date: November 20, 2002
Creator: Gabitto, Jorge & Barufet, Maria
Partner: UNT Libraries Government Documents Department

Investigation of Multiscale and Multiphase Flow, Transport and Reaction in Heavy Oil Recovery Processes

Description: The emphasis of this work was on investigating the mechanisms and factors that control the recovery of heavy oil with the objective to improve recovery efficiencies. For this purpose the interaction of flow transport and reaction at various scales from the pore network to the field scales were studied. Particular mechanisms to be investigated included the onset of gas flow in foamy oil production and in in-situ steam drive, gravity drainage in steam processes, the development of sustained combustion fronts and the propagation of foams in porous media. Analytical, computational and experimental methods were utilized to advance the state of the art in heavy oil recovery. Successful completion of this research was expected to lead to improvements in the Recovery efficiency of various heavy oil processes.
Date: March 11, 2002
Creator: Yorstos, Yanis C.
Partner: UNT Libraries Government Documents Department

Modification of reservoir chemical and physical factors in steamfloods to increase heavy oil recovery

Description: Thermal methods, and particularly steam injection, are currently recognized as the most promising for the efficient recovery of heavy oil. Despite significant progress, however, important technical issues remain open. Specifically, still inadequate is our knowledge of the complex interaction between porous media and the various fluids of thermal recovery (steam, water, heavy oil, gases, and chemicals). While, the interplay of heat transfer and fluid flow with pore- and macro-scale heterogeneity is largely unexplored. The objectives of this contract are to continue previous work and to carry out new fundamental studies in the following areas of interest to thermal recovery: displacement and flow properties of fluids involving phase change (condensation-evaporation) in porous media; flow properties of mobility control fluids (such as foam); and the effect of reservoir heterogeneity on thermal recovery. The specific projects are motivated by and address the need to improve heavy oil recovery from typical reservoirs as well as less conventional fractured reservoirs producing from vertical or horizontal wells. During this quarter work continued on: development of relative permeabilities during steam injection; optimization of recovery processes in heterogeneous reservoirs by using optimal control methods; and behavior of non-Newtonian fluid flow and on foam displacements in porous media.
Date: December 31, 1996
Partner: UNT Libraries Government Documents Department

Modification of reservoir chemical and physical factors in steamfloods to increase heavy oil recovery

Description: Thermal methods, and particularly steam injection, are currently recognized as the most promising for the efficient recovery of heavy oil. Despite significant progress, however, important technical issues remain open. Specifically, still inadequate is our knowledge of the complex interaction between porous media and the various fluids of thermal recovery (steam, water, heavy oil, gases, and chemicals). While, the interplay of heat transfer and fluid flow with pore- and macro-scale heterogeneity is largely unexplored. The objectives of this contract are to continue previous work and to carry out new fundamental studies in the following areas of interest to thermal recovery: displacement and flow properties of fluids involving phase change (condensation-evaporation) in porous media; flow properties of mobility control fluids (such as foam); and the effect of reservoir heterogeneity on thermal recovery. The specific projects are motivated by and address the need to improve heavy oil recovery from typical reservoirs as well as less conventional fractured reservoirs producing from vertical or horizontal wells. During this past quarter, work continued on: the development of relative permeabilities during steam displacement; the optimization of recovery processes in heterogeneous reservoirs by using optical control methods; and in the area of chemical additives, work continued on the behavior of non-Newtonian fluid flow and on foam displacements in porous media.
Date: December 31, 1996
Creator: Yortsos, Y.C.
Partner: UNT Libraries Government Documents Department

Increasing heavy oil reserves in the Wilmington Oil Field through advanced reservoir characterization and thermal production technologies. Annual report, March 30, 1995--March 31, 1996

Description: The objective of this project is to increase heavy oil reserves in a portion of the Wilmington Oil Field, near Long Beach, California, by implementing advanced reservoir characterization and thermal production technologies. Based on the knowledge and experience gained with this project, these technologies are intended to be extended to other sections of the Wilmington Oil Field, and, through technology transfer, will be available to increase heavy oil reserves in other slope and basin clastic (SBC) reservoirs. The project involves implementing thermal recovery in the southern half of the Fault Block II-A Tar zone. The existing steamflood in Fault Block II-A has been relatively inefficient due to several producibility problems which are common in SBC reservoirs. Inadequate characterization of the heterogeneous turbidite sands, high permeability thief zones, low gravity oil, and nonuniform distribution of remaining oil have all contributed to poor sweep efficiency, high steam-oil ratios, and early steam breakthrough. Operational problems related to steam breakthrough, high reservoir pressure, and unconsolidated formation sands have caused premature well and downhole equipment failures. In aggregate, these reservoir and operational constraints have resulted in increased operating costs and decreased recoverable reserves. A suite of advanced reservoir characterization and thermal production technologies are being applied during the project to improve oil recovery efficiency and reduce operating costs.
Date: September 1, 1997
Partner: UNT Libraries Government Documents Department

Increasing heavy oil reserves in the Wilmington oil field through advanced reservoir characterization and thermal production technologies. Quarterly report, July 1 - September 30, 1996

Description: The project involves improving thermal recovery techniques in a slope and basin clastic (SBC) reservoir in the Wilmington field, Los Angeles Co., Calif. using advanced reservoir characterization and thermal production technologies. This is the sixth quarterly technical progress report for the project. Through September 1996, the project continues to make good progress but is slightly behind schedule. Estimated costs are on budget for the work performed to date. Technical achievements accomplished during the quarter include placing the first two horizontal wells on production following cyclic steam stimulation, completing several draft technical reports and preparing presentations on the deterministic geologic model, steam channel crossing and horizontal well drilling for technical transfer. Cyclic steam injection into the first two horizontal wells was completed in June 1996 and initial oil production from the project began the same month. Work has commenced on the stochastic geologic and reservoir simulation models. High temperature core work and reservoir tracer work will commence in the First Quarter 1997.
Date: December 1, 1996
Creator: Hara, S.
Partner: UNT Libraries Government Documents Department

Modification of chemical and physical factors in steamflood to increase heavy oil recovery

Description: This report covers the work performed in the various physicochemical factors for the improvement of oil recovery efficiency. In this context the following general areas were studied: (1) The understanding of vapor-liquid flows in porous media, including processes in steam injection; (2) The effect of reservoir heterogeneity in a variety of foams, from pore scale to macroscopic scale; (3) The flow properties of additives for improvement of recovery efficiency, particularly foams and other non-Newtonian fluids; and (4) The development of optimization methods to maximize various measures of oil recovery.
Date: January 19, 2000
Creator: Yortsos, Yanis C.
Partner: UNT Libraries Government Documents Department

Heavy and Thermal Oil Recovery Production Mechanisms, SUPRI TR-127

Description: The program spans a spectrum of topics and is divided into five categories: (i) multiphase flow and rock properties, (ii) hot fluid injection, (iii) primary heavy-oil production, (iv) reservoir definition, and (v) in-situ combustion.
Date: September 7, 2001
Creator: Kovscek, Anthony R.; Brigham, William E. & Castanier, Louis M.
Partner: UNT Libraries Government Documents Department

Increasing heavy oil reservers in the Wilmington oil Field through advanced reservoir characterization and thermal production technologies, technical progress report, October 1, 1996--December 31, 1996

Description: The project involves improving thermal recovery techniques in a slope and basin clastic (SBC) reservoir in the Wilmington field, Los Angeles Co., Calif. using advanced reservoir characterization and thermal production technologies. The existing steamflood in the Tar zone of Fault Block (FB) 11-A has been relatively inefficient because of several producibility problems which are common in SBC reservoirs. Inadequate characterization of the heterogeneous turbidite sands, high permeability thief zones, low gravity oil, and nonuniform distribution of remaining oil have all contributed to poor sweep efficiency, high steam-oil ratios, and early steam breakthrough. Operational problems related to steam breakthrough, high reservoir pressure, and unconsolidated formation sands have caused premature well and downhole equipment failures. In aggregate, these reservoir and operational constraints have resulted in increased operating costs and decreased recoverable reserves. The advanced technologies to be applied include: (1) Develop three-dimensional (3-D) deterministic and stochastic geologic models. (2) Develop 3-D deterministic and stochastic thermal reservoir simulation models to aid in reservoir management and subsequent development work. (3) Develop computerized 3-D visualizations of the geologic and reservoir simulation models to aid in analysis. (4) Perform detailed study on the geochemical interactions between the steam and the formation rock and fluids. (5) Pilot steam injection and production via four new horizontal wells (2 producers and 2 injectors). (6) Hot water alternating steam (WAS) drive pilot in the existing steam drive area to improve thermal efficiency. (7) Installing a 2100 foot insulated, subsurface harbor channel crossing to supply steam to an island location. (8) Test a novel alkaline steam completion technique to control well sanding problems and fluid entry profiles. (9) Advanced reservoir management through computer-aided access to production and geologic data to integrate reservoir characterization, engineering, monitoring, and evaluation.
Date: May 11, 1997
Creator: Hara, S.
Partner: UNT Libraries Government Documents Department

Research on oil recovery mechanisms in heavy oil reservoirs

Description: The research described here was directed toward improved understanding of thermal and heavy-oil production mechanisms and is categorized into: (1) flow and rock properties, (2) in-situ combustion, (3) additives to improve mobility control, (4) reservoir definition, and (5) support services. The scope of activities extended over a three-year period. Significant work was accomplished in the area of flow properties of steam, water, and oil in consolidated and unconsolidated porous media, transport in fractured porous media, foam generation and flow in homogeneous and heterogeneous porous media, the effects of displacement pattern geometry and mobility ratio on oil recovery, and analytical representation of water influx.
Date: March 16, 2000
Creator: Kovscek, Anthony R. & Brigham, William E., Castanier, Louis M.
Partner: UNT Libraries Government Documents Department

Transport and Phase Equilibria Properties for Steam Flooding of Heavy Oils

Description: The objectives of this research included experimental determination and rigorous modeling and computation of phase equilibria, volumetric, and transport properties of hydrocarbon/CO2/water mixtures at pressures and temperatures typical of steam injection processes for thermal recovery of heavy oils.
Date: December 18, 2001
Creator: Gabitto, Jorge & Barrufet, Maria
Partner: UNT Libraries Government Documents Department

Modeling Permeability Alteration in Diatomite Reservoirs During Steam Drive, SUPRI TR-113

Description: There is an estimated 10 billion barrels of original oil in place (OOIP) in diatomaceous reservoirs in Kern County, California. These reservoirs have low permeability ranging from 0.1 to 10 mD. Injection pressure controlled steam drive has been found to be an effective way to recover oil from these reservoir. However, steam drive in these reservoirs has its own complications. The rock matrix is primarily silica (SiO2). It is a known fact that silica is soluble in hot water and its solubility varies with temperature and pH. Due to this fact, the rock matrix in diatomite may dissolve into the aqueous phase as the temperature at a location increases or it may precipitate from the aqueous phase onto the rock grains as the temperature decreases. Thus, during steam drive silica redistribution will occur in the reservoir along with oil recovery. This silica redistribution causes the permeability and porosity of the reservoir to change. Understanding and quantifying these silica redistribution effects on the reservoir permeability might prove to be a key aspect of designing a steam drive project in these formations.
Date: August 9, 1999
Creator: Bhat, Suniti Kumar & Kovscek, Anthony R.
Partner: UNT Libraries Government Documents Department

Class III Mid-Term Project, "Increasing Heavy Oil Reserves in the Wilmington Oil Field Through Advanced Reservoir Characterization and Thermal Production Technologies"

Description: The overall objective of this project was to increase heavy oil reserves in slope and basin clastic (SBC) reservoirs through the application of advanced reservoir characterization and thermal production technologies. The project involved improving thermal recovery techniques in the Tar Zone of Fault Blocks II-A and V (Tar II-A and Tar V) of the Wilmington Field in Los Angeles County, near Long Beach, California. A primary objective has been to transfer technology that can be applied in other heavy oil formations of the Wilmington Field and other SBC reservoirs, including those under waterflood. The first budget period addressed several producibility problems in the Tar II-A and Tar V thermal recovery operations that are common in SBC reservoirs. A few of the advanced technologies developed include a three-dimensional (3-D) deterministic geologic model, a 3-D deterministic thermal reservoir simulation model to aid in reservoir management and subsequent post-steamflood development work, and a detailed study on the geochemical interactions between the steam and the formation rocks and fluids. State of the art operational work included drilling and performing a pilot steam injection and production project via four new horizontal wells (2 producers and 2 injectors), implementing a hot water alternating steam (WAS) drive pilot in the existing steamflood area to improve thermal efficiency, installing a 2400-foot insulated, subsurface harbor channel crossing to supply steam to an island location, testing a novel alkaline steam completion technique to control well sanding problems, and starting on an advanced reservoir management system through computer-aided access to production and geologic data to integrate reservoir characterization, engineering, monitoring, and evaluation. The second budget period phase (BP2) continued to implement state-of-the-art operational work to optimize thermal recovery processes, improve well drilling and completion practices, and evaluate the geomechanical characteristics of the producing formations. The objectives were to further improve reservoir ...
Date: March 31, 2007
Creator: Hara, Scott
Partner: UNT Libraries Government Documents Department