bluuebunny/crossref_metadata_2025_split huggingface dataset:
Finite Elements With Characteristics for Two-Component Incompressible Miscible Displacement
Authors: Russell Thomas Fletcher 
Published: December 2007

ABSTRACT
An efficient method for modeling convection-dominated flows is presented and applied to miscible displacement in a porous medium. The method uses characteristics to model convection and finite elements for diffusion and dispersion, thereby treating each physical process with a well-suited numerical scheme. A finite difference analogue can also be formulated.
Numerical results are given that show that the method can simulate adverse mobility ratio displacements accurately without suffering from grid orientation, numerical dispersion, or overshoot. The use of characteristics allows time steps to be an order of magnitude larger than in previously proposed methods, with a corresponding increase in efficiency. Unlike many procedures utilizing characteristics, this method is easily applied in two or three dimensions.
Simulations of Chemical Flooding—Comparison with Experimental Data
Authors: Carney Bruce , Finlayson Bruce A. 
Published: December 2007

ABSTRACT
A compositional simulator is used to model chemical flooding. Computed results are compared to laboratory studies available in the literature. Special representations were devised to model the surface tension and phase behavior of Types II(-) and III on ternary diagrams. Continuous core-flood experiments of Healy, Reed and Carpenter8 were modeled. Results from models with high dispersion levels compare favorably to the data for cumulative recovery and fractional flow of oil with several different injection compositions. Core-flood experiments of Willhite, Green, Okoye and Looney9 have been simulated for situations involving a slug injection of microemulsion. Results obtained for models with high dispersion levels compare favorably with experimental data for cumulative recovery and fractional flow of oil. Surfactant and alcohol concentration profiles are not well modeled because the ternary phase diagram is not appropriate to this system.
The model parameters were then changed to allow a sensitivity analysis. For parameters representative of these laboratory studies the results are not strongly dependent on the dispersion level. Standard data was used for relative permeability, and the detrapping parameters can be changed to simulate other cases or to improve the comparison with experiment.
Reservoir Simulation and the In-house Vector Processor: Experience for the First Year
Authors: Killough J. E. , Levesque J. M. 
Published: December 2007

ABSTRACT
Over the past year, ARCO Oil and Gas Company has had the first large scale in-house vector processor (the CRAY-1S) in the oil industry. During that time, a considerable effort has been spent on conversion of reservoir simulator codes to perform efficiently in a vector processor environment. The following paper describes some of the more important aspects of these experiences during the past year. The vector strongly implicit procedure algorithm is presented along with timing comparisons. A unique method for vectorization of a compositional reservoir simulation model is also presented. The paper discusses difficulties with the IBM/CRAY interface and how these were overcome. Finally, a method is described for utilizing the capabilities of the CRAY-1S I/O processor for problems that are not contained in memory.
The Kuparuk River Field: A Regression Approach to Pseudo-Relative Permeabilities
Authors: Johnson J. B. , Nanney Michael M. , Killough John E. , Lin Y. T. 
Published: December 2007

ABSTRACT
The Kuparuk River field located about twenty-five miles west of the Prudhoe Bay Unit, North Slope Alaska, represents a large accumulation of oil spread over a wide areal extent. The large areal extent of the reservoir presented a major difficulty for full scale reservoir simulation of this field especially under waterflood conditions. To overcome this difficulty a regression approach was used to match finely-gridded, three-dimensional waterflood models with coarse-grid models. Matches were obtained by varying in an optimal manner the pseudo-relative permeability relationship and the interblock weighting of relative permeabilities. It was found that for both the waterflood case and the reinjected gas displacement case excellent matches of the finely gridded model results could be obtained with an extremely coarse-gridded model. Matches were obtained automatically using a non-linear regression approach in a relatively small amount of computer time. In addition, sensitivity analysis showed that the pseudo-relative permeabilities thus generated were insensitive to reasonable variations in waterflood rate and to timing of waterflood initiation. With this technique it was possible to construct a fieldwide model for facilities planning and to study the effect of facilities on ultimate recovery from the reservoir.
An Analysis of the Estimation of Reservoir Properties from Waterflooding Data
Authors: Watson A. T. , Gavalas G. R. , Seinfeld J. H. 
Published: December 2007

ABSTRACT
The estimation of porosity, absolute permeability and relative permeabilities from pressure drop and production data is considered for water-oil flow in a linear reservoir. We examine some of the related fundamental questions associated with this history matching problem, namely which of the above properties can be estimated, in principle, from pressure data, water-oil ratio data, or both, and how accurately can they be estimated. Analytical expressions derived by extension of Welge's method to heterogeneous reservoirs are used to study the estimation of porosity and absolute permeability distributions. A sensitivity analysis and an error covariance analysis are employed to study the feasibility and accuracy of estimating relative permeability parameters.
Effects of Diagenesis on Pore Texture and Petrophysical Properties of Sandstone Reservoir and Its Geological Significance
Authors: Guohua Zhu 
Published: December 2007

ABSTRACT
This paper deals with diagenesis of Yan-10 Sandstones, Yanan Series, jurassic—the main producing horizons in an exploratory area in Shan-Gan-Ning Basin. The effects of diagenesis on pore texture and petrophysical properties of sandstone, its effects on forming trapping conditions for oil pools, the genesis of low permeability zone near the oil-water boundary, as well as secondary pores together with authigenic clay minerals of sandstone are presented. Furthermore, the paper describes briefly Yan-10 sandstones in some other areas.
Bottom Hole Assembly Problems Solved by Beam-Column Theory
Authors: Jiazhi Bai 
Published: December 2007

ABSTRACT
The bending portion of a multiple-stabilizer bottom hole assembly can be considered as a string of several simply-supported beams loaded by axial compressive forces together with transverse ones. By the beam-column theory, a system of "equations of three moments" can be obtained. The essential aim to design a bottom hole assembly with special requirements is to produce a desirable reactive side force on the bit from the formation. While there are numerous parameters that would influence the value of this force, the effect of each of them can be evaluated from the position it occupies in those equations. This paper is particularly focused on the analysis of pendulum assemblies with two stabilizers and affirms their obvious advantages over those with only one stabilizer or no stabilizer.
Practice and Viewpoint on Regional Cathodic Protection in the Guanghua Oil Field
Authors: Yinglong Zhao 
Published: December 2007

ABSTRACT
The control of corrosion on pipeline network for gathering and transporting and on casings of oil and water well is a matter of primary importance to the prolongation of their service life, the cutting down of their operattion costs, the reduction of energy loss and the improvement of the level of management. From seven years field experiments in cathodic protection on a regional scale in the Guanghua oil field, this paper attempts to give a review of the experiences in respect to: the necessity of joint protection of pipeline network and casings, the method of measuring and ¼ayβ of eliminating interferences, the rational layout of anodic groundbeds and distribution of protection current the method of monitoring the state of casing protection and the technological and economic problems involved.
An Improved Technique For Predicting The Severity Of Calcium Carbonate
Authors: Valone Frederick William , Skillern Kenneth Richard 
Published: December 2007

ABSTRACT
A new approach for computing calcite scaling tendencies is described. Computed values are obtained by exactly solving the chemical equilibria expressions for calcite precipitation. To date, extremely accurate predictions of calcite scale deposition in oilfield systems have been made based on this computed scaling value.
Performance Comparisons for Reservoir Simulation Problems on Three Supercomputers
Authors: Stanat Patricia L. , Nolen James S. 
Published: December 2007

ABSTRACT
Recent decisions by several of the major oil companies to acquire vector processing computers indicate the growing acceptance of these machines in exploration and production applications. While seismic processing has probably provided the primary justification for these acquisitions, suitability for numerical reservoir simulation should be considered in evaluating such hardware.
This paper extends the results presented in a previous paper by comparing the performance of the CYBER 203, CYBER 205, and CRAY-1 S computers when running a three-dimensional, three-phase reservoir simulator.(1) Each of three different problems were run on the 203 and 205, and all three machines were used to solve one problem.
As might be expected, the results show that the improvement obtained from one computer to the next is somewhat problem dependent. The parameters affecting the differences include the vector length and the amount of scalar code executed relative to vector code. In the three cases, the CYBER 205 demonstrated run times of 2.3 to 3.4 times faster than the CYBER 203. The CYBER 205 was found to be 1.6 times faster than the CRAY-1 S in the case where all three machines were tested.
Seismic Imaging in Enhanced Recovery
Authors: Nur Amos M. 
Published: December 2007

ABSTRACT
Laboratory measurements of seismic velocities and attenuation in fluid saturated rock samples strongly suggest that detectable changes in these properties are anticipated upon steam flooding of heavy oil reservoirs, or during other EOR operations. Such changes could be monitored with seismic array of receivers and transmitters situated around the region of enhanced recovery. The array will yield seismic wave travel times and amplitudes and their temporal and spatial changes. Inverting these measured values, it is possible to determine the distribution of velocities and Q within the reservoir. These distributions can uniquely be interpreted in terms of the distribution of a steam phase in the reservoir, using laboratory determined seismic response of reservoir rock samples.
Laboratory Investigation of the Oxygen Combustion Process for Heavy Oil Recovery
Authors: Moss Jon T. , Cady Gilbert V. 
Published: December 2007

Abstract
The laboratory investigations were conducted using core material and produced oil from a typical Alberta heavy oil reservoir. The experiments produced oil from a typical Alberta heavy oil reservoir. The experiments established combustion characteristics using air and the CTD process for thermal oil recovery. Both the combustion and CTD tests indicated the oil's favorable response to thermal recovery. The results of laboratory studies using oxygen and oxygen with water injection have indicated that the enriched air process, as Ramey suggested almost thirty years ago, is not only viable as an oil recovery method, but the process is also highly desirable.

Introduction
The in-situ combustion process has been thoroughly described in the literature over the last three decades. Early investigators used various methods for control of the combustion process. Sinclair's early field experiments in Kansas and Oklahoma advocated use of the heat wave process to control combustion variables. Volumes of air, gas and recycled gas were used to propagate a flame front through the reservoir. Worthington and the Forrest Oil Company used gas, air and steam in their 1953 field test in Illinois. Air was injected in the forward combustion process developed by Magnolia and General Petroleum in early field tests in Oklahoma and California. From these diverse, yet similar, pilot projects, Ramey suggested several alternate operational schemes for in-situ combustion. One of these proposals was to inject air enriched with oxygen.
Distinct improvement in combustion techniques came in the early 1960's when Tejas Engineers pilot tested the Combination Thermal Drive (CTD) process using air-water injection and AMOCO developed the COFCAW process. process using air-water injection and AMOCO developed the COFCAW process. To further enhance combustion drive, Dome Petroleum Limited initiated reservoir and laboratory studies to determine the process variables using oxygen as the injected gas. Several laboratory combustion tube experiments have been made using air, air and water, oxygen and oxygen-water injection.
A Practical Iterative Scheme for Coupling Geomechanics With Reservoir Simulation
Authors: Samier Pierre , de Gennaro Sergio 
Published: December 2007

Abstract
The use of reservoir simulation coupled with geomechanics to model physical phenomena such as compaction, subsidence, induced fracturing, enhancement of natural fractures and/or fault activation, SAGD recovery etc.., has been increasing. Among different methods investigated by researchers. The iterative explicit method appears to be the preferred method for field-scale simulation.
This method is a loose coupled approach between a reservoir and a geomechanical simulator. At user-defined steps, the fluid pressures are transmitted to the geomechanical tool which computes the actual stresses and reports the modifications of porosities and permeabilities back to the reservoir simulator. In the classical iterative scheme, at each stress equilibration step, the reservoir simulation needs to be restarted from the previous converged step. This scheme can be difficult to implement within an industrial IT environment.
This paper presents a new iterative scheme which allows:
any reservoir simulator, to be coupled with any nonlinear FEM package for the stress analysis without any limitation on the functionality of either simulator.
The convergence of this new scheme is discussed and results are presented for three cases described below.
The first case is a validation case used by other SPE papers. The second case is a synthetic model of a highly compacting reservoir sensitive to water saturation. The third one is a full field reservoir model. Faults are modeled inside the reservoir CPG grid and also inside the geomechanical mesh using specific cohesive elements.
In all cases, convergence is achieved in a few iterations and results are comparable to those obtained with previously tested methods. The feasibility of the proposed coupling approach using industrial software is proved. Another advantage compared to the standard iterative scheme is the ability to compare production profiles over the complete time history at the end of each geomechanical iteration. The reservoir engineer evaluates the coupling effects and ends the iterative process when production curves variations between two iterations are no longer significant.
Performance of DOE's Micellar-Polymer Project in Northwest Oklahoma
Authors: Thomas Rex D. , Spence Kenneth L. , Burtch Fred W. , Lorenz Philip B. 
Published: December 2007

Abstract
DOE's Bartlesville Energy Technology Center has completed a micellar-polymer flood in the Delaware-Childers Field in NE Oklahoma. The producing horizon was the oil-wet Bartlesville sandstone, at a depth of 620 to 700 ft., which has a net pay thickness of 52 ft, an average permeability of 100 md, and an average porosity of 21 percent. Estimated oil saturation was 32 to 36 percent of 33° API gravity oil. Injection of the approximately 0.1 PV of micellar fluid was started April 28, 1976, following five months of brine preflush. Micellar injection was completed and polymer injection started October 5, 1976. Injection of the approximately 0.4 PV of polymer was completed in August 1979 and fresh water injection started. Pressure and flow for the injection-wells were monitored instrumentally. Spot checks for the quality of injected and produced fluids were made by chemical analysis. The project was not technically or economically a success, but did provide much information that is proving useful in other similar projects. A small amount of tertiary oil was produced by the micellar-polymer system.
A Numerical Model of the Non-Isothermal Flow of Carbon Dioxide in Wellbores
Authors: Cranshaw Mark B. , Bolling John D. 
Published: December 2007

ABSTRACT
A numerical model of non-isothermal flow in pure carbon dioxide production or injection wells was developed. The model includes single or two-phase flow, heat transfer between the wellbore and its surroundings, and an accurate representation of the thermophysical properties of carbon dioxide, even near its critical point. Model predictions matched pressures measured during a field production test to within 30 psi and temperatures to within 3°F for flow rates between 4 and 22 MMscf/D. Sensitivities to wellhead conditions and flow rate for a pure carbon dioxide injector were examined with the model. Explanations of behavior during production and injection should improve our understanding of the use of carbon dioxide in the oil field.
Operational Experiences of a Downhole Steam Generator
Authors: Marshall Billy W. 
Published: December 2007

ABSTRACT
The U. S. Department of Energy has supported the development of downhole steam generators for enhanced oil recovery as a part of Project DEEP STEAM. A final step in the development program was to deploy a downhole steam generator (DHSG) in the field to demonstrate its reliable operation and to evaluate the effect of the combined steam/exhaust products effluent on the reservoir. Sandia National Laboratories entered Into an agreement with the City of Long Beach to place two direct contact, high pressure combustors in the Wilmington Field in Long Beach, California. These units, one downhole and the other on the surface, have now been operated for a few months and gas communication with the production wells established. The operational experiences of this field experiment are discussed.
Downhole Steam Generator — Field Tests
Authors: Eson Rod L. 
Published: December 2007

ABSTRACT
Excessive air pollution and heat losses up to 32% in the surface lines and out the stacks of conventional generators are reasons why conventional steam generation is inefficient. These problems are addressed and overcome through the use of a direct-fired Downhole Steam Generator (DSG). By carrying out the combustion process at high pressure, and then adding water, a mixture of carbon dioxide, nitrogen and steam is discharged directly into the heavy oil reservoir. This paper documents a series of field tests of a direct-fired DSG showing its ability to produce and inject high quality steam into heavy oil reservoirs without the need for expensive stack scrubbers to remove sulfur dioxide (SO2), as well as sophisticated nitrogen oxides (NOX) control techniques. Results from the 6 in. diameter, 6 ft long, 7.1 MMBtu/hr DSG showed that corrosion can be controlled and production can be improved dramatically in actual field tests in California heavy oil reservoirs.
Some speculation was given to the positive effects from the injection of the combustion products with the steam. Field tests indicate that in at least one case, a 639 ft deep, 11° API gravity well with low reservoir pressures (100 psi) flowed after injection of only 1,393 barrels of steam along with the combustion gases of the direct-fired Downhole Steam Generator.
This field development of the direct-fired DSG not only has shown that it can be an effective Enhanced Oil Recovery (EOR) technique in existing heavy oil reservoirs, but also provides a feasible means of recovery for the 5-7 billion barrels of heavy oil known to exist in the United States below 2,500 ft.
Design Considerations of a Tension Leg Platform
Authors: Ghosh Susobhan , Chou Frank S. , Huang Edward W. 
Published: December 2007

ABSTRACT
The offshore industry is presently reviewing the design and installation of various concepts for deepwater platforms. The concept most favored is probably that of the Tension Leg Platform (TLP). The design of a TLP has many challenging and intriging aspects, some of which are unique to itself. TLP'S are relatively new to the offshore industry, thus there are no standard design guides. In the years to come, as the industry learns more about the behavior of TLP'S; the design methods are expected to improve accordingly. A TLP design includes the design of the vessel, tether system, processing equipment and hardware e.g., well head system, drilling systems, tether handling equipment etc. This paper summarizes the authors' experience dealing with various challenging engineering problems in TLP design, and outlines the important design considerations which a designer is expected to encounter designing a TLP. A brief review of analytical tools and how they are applied in the design of a TLP are included in the paper. No attempt has been made to cover aspects related to hardware design.
Improved Liner Cementing Techniques for Alaska's Prudhoe Bay Field
Authors: Kolthoff Karl W. , Scales Glyn H. 
Published: December 2007

ABSTRACT
This paper describes the current equipment and techniques used to reciprocate and cement liners in Alaska's Prudhoe Bay Field. Liner reciprocation was started in Prudhoe Bay by BP Alaska, Inc., using hydraulic-set hangers during 1976. Liner reciprocation was initially developed to improve mud displacement thereby improving cement bonding in high-angle wells. To date, more than 210 deviated wells have been successfully completed using the methods described in this paper.
Typical Prudhoe Bay Unit wells are completed with approximately 1,500 ft of 7 in. 29#/ft L-80 liner hung across 8-1/2 in. open hole at 10,800 ft MD in hole angles up to 67 degrees. Liners are routinely reciprocated while conditioning mud and while circulating and displacing cement slurries. The cement is preceded with a chemical or water pre-flush, and the entire slurry is displaced at turbulent flow rates. The hanger is hydraulically set with a liner wiper plug. Current technology includes the use of the latest recirculating cementing unit as well as liner hanger equipment designed for compactness, low-flow restriction, and high-load capacity.
Reciprocating liners in the Prudhoe Bay Unit has resulted in a significant drop in the number of squeeze cement jobs of the liner and/or liner lap. Success has been verified by lap in-flow testing, low-water production rates, and a good cement bonding at the critical oil/ water and gas/oil contacts.
A New Low-Cost Permafrost Cementing System
Authors: Benge O. G. , Jones R. R. , Dresher T. D. , Dolan R. T. 
Published: December 2007

ABSTRACT
Extensive research has resulted in the development and subsequent field application of a new extended cement system for use in permafrost cementing projects. The use of this extended system instead of more expensive specialized cement systems leads to a reduction in overall permafrost cementing costs.
This paper reviews the design requirements for permafrost cementing. It also provides laboratory data and reviews the methods which have met those requirements.
Results of actual field application of the newly designed cement system and comparison with another specialized extended system are also presented.