bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Investigation of the Recovery of the Bradford Crude by Steam Injection
Authors: Ozen A.S. , Ali S.M. Farouq 
Published: December 2007

Laboratory tests indicate that steam injected at relatively low pressures is effective in recovering oil from previously waterflooded porous media. They also indicate that the relative effect of an increase in temperature on oil recovery is much more pronounced at higher than at lower temperatures.

Introduction
In spite of the recently growing interest in continuous steam injection as an oil recovery technique, very few laboratory investigations of steam drive or steamflooding have been reported. The pioneering work of Willman et al. provided much useful information on the mechanism of a steamflood. More recently, Baker 2 has described results of similar studies conducted in a laminar flow model. While actual field tests will decide the effectiveness of a steamflood in a given area, laboratory studies, nevertheless, provide information that can be used to calculate the maximum oil recovery obtainable under a given set of conditions.
The present investigation was designed basically to obtain information on the response of a fight crude oil (Bradford crude, 450 API gravity) to a steamflood in a previously waterflooded reservoir. (Many reservoirs in the Appalachian area are in this category, and could possibly give a third yield of oil by a steamflood.) Moreover, an attempt was made to ascertain the role of heat losses in laboratory studies of steam injection. Few previously published works have considered this effect.
Steamflooding has been tested in the Appalachian oil fields. In spite of the several early failures, attributed to poor engineering and a lack of basic information on the crude oils involved, steamflooding has been successful in recovering large quantities of oil, as evidenced by steamfloods currently in progress. The results of the present investigation support this view.

Experimental Apparatus
A schematic diagram of the experimental apparatus used in this study - for the case of the consolidated core, Core No. 1 (see Table 1 ) -is shown in Fig. 1. The core was mounted in a Viton rubber sleeve, the ends of which were clamped to steel end plates provided with suitable connections and O-ring seals. The whole assembly was placed within a high- pressure casing, containing a nonvolatile oil. It was possible to heat the oil - and hence the core assembly - to any desired temperature by means of thermostatically controlled circular heater segments mounted on the outside of the casing. The oil within the casing could be kept at a constant pressure, regardless of the temperature, by means of a pressure regulator pressurized by a hydraulic accumulator and a pressure switch. If the casing pressure should increase above the preset pressure, the regulator could allow some of the oil to leak out of the casing. On the other hand, if the casing pressure should decrease below the set point, the pressure switch could turn on a pump, which would pump oil into the casing until the desired pressure was attained.
Simpler experimental set-ups were employed for Cores 2 and 3.
JPT
P. 692ˆ
Oil Recovery by Gravity Drainage Into Horizontal Wells Compared With Recovery From Vertical Wells
Authors: Dykstra Herman , Dickinson Wade 
Published: December 2007

SummaryGravity drainage is a significant factor in many EOR projects, particularly those involving steam stimulation and extended recovery from depleted reservoirs. This paper compares the effect of dip, reservoir thickness, oil mobility, and well spacing on production from horizontal vs. vertical wells. Total production from vertical and horizontal wells as a function of time also is compared. The basic physical concept involved in this study is the constriction coefficient. For a horizontal well, the constriction coefficient is larger than that for a vertical well at the start of drainage but that difference decreases with time.
Analytical and Numerical Solution of Oil Recovery From Fractured Reservoirs With Empirical Transfer Functions
Authors: Kazemi Hossein , Gilman J. R. , Elsharkawy A. M. 
Published: December 2007

Summary
An analytical and a numerical solution to Buckley-Leverett flow in a ID fractured porous rock is given. An empirical matrix/fracture transfer function was used. The numerical solution is fast and is adaptable to 3D field problems. The limitations of empirical transfer functions are discussed.
A Computer Technique for Analyzing Pumping Well Performance
Authors: Patton L. Douglas 
Published: December 2007

Abstract
A computerized analytical technique for investigating sucker rod pumping well performance develops load-position values (dynagraphs) at the pump, at desired points in the rod string and at the polished rod through use of a mathematical model of the sucker rod installation. Using the load-position diagrams of the pump, junction points and polished rod, quantitative deductions may be made regarding the mechanical condition and performance of the down-hole equipment (rod string, pump, tubing anchor, etc.) and the physical properties of the well itself (pump submergence, gas interference, fluid pound, etc.). Analysis of subsurface dynagraphs from several cave histories is discussed.

Introduction
Production men have recognized for years that a more complete knowledge of rod pumping performance would suggest means of lowering lifting costs, making more appropriate installation designs and increasing the proportion of oil economically recoverable by rod pumping.
It was this need for knowledge that led to intensive studies from 1927 to 1943. During those years the polished rod dynamometer (1927), the bottom-hole pressure bomb (1929), the pump dynagraph (1936) and the sonic fluid-level sounder (1936) were developed. During that time many engineers used those tools to develop the theories on which our present knowledge of sucker rod pumping is based.
Contributions made since 1943, in an effort to correlate data obtained from the various instruments, are mostly elaborations and refinements of the basic principles established during the preceding period. A notable exception is the Gibbs-Neely mathematical technique that analyzes pumping well performance with a digital computer. In effect, the technique yields all the information derived from these mechanical devices but has the added advantage of requiring only one series of measurements taken and recorded at the polished rod.
Experimental Investigation of Hydrate Formation and Dissociation in Consolidated Porous Media
Authors: Youslf M. H. , Sloan E. D. 
Published: December 2007

Summary
This paper describes the first uniform formation of natural gas hydrates in Berea sandstone cores by use of a flow system. The hydrate formation was monitored by pressure drop and changes in electric resistance along three cores of three different permeabilities. Formation procedures, such as annealing to ensure uniformity, and the effects of surfaces on equilibria are discussed. Hydrates were dissociated through depressurization, as is done for gas recovery from the Messoyakha hydrate reservoir in the USSR. During the dissociation, two types of rate behavior were observed as functions of the displacement of the dissociation pressure from the equilibrium value. Conclusions and implications for the production of natural gases from hydrate deposits are discussed.
Deploying Mainframe Technical Applications on the PC
Authors: Glynn C. J. 
Published: December 2007

Summary
Numerous engineering applications on the corporate mainframe network running VM/CMS have been redesigned and deployed on PC’s running DOS. The majority of these applications apply to operations engineering and include calculating fluid properties, multiphase flow pressure drops, and optimum designs for both downhole and surface equipment. The redesign effort focused on the user interface with only minor changes being made to the calculation routines. The PC version of the applications execute faster, at a lower cost per execution, and require less support and training than the corresponding mainframe version.
PC and Mainframe Computer-Graphics Techniques Applied to Volumetric Evaluation of a Mature Oil Field
Authors: Newell K. David , Schoeling Lanny G. , Wong Jan-Chung 
Published: December 2007

Summary
Mapping and volumetric analysis of large reservoirs are important steps in evaluating mature oil fields for secondary and tertiary development. This paper describes how a research group mapped and conducted an extensive volumetric analysis on the Zenith pool, a large, mature oil field in central Kansas, with a Data General MV20000 minicomputer with Surface III™ mapping software and a PC with Surfer™ and spreadsheet software.
A step-by-step procedure was developed to generate structure, isopach, and porosity maps for the five main reservoirs in the field. Lotus 123™ spreadsheets were developed to compile locations, formation tops, and other critical data for more than 500 wells. These data were sent to the minicomputer to generate contour maps depicting structure, isopachs, and porosities with output directed to an electrostatic color plotter. Grid-to-grid manipulation and cross multiplication of these contour maps allowed construction of a porosity-foot map for each reservoir. The final contour maps incorporated the effects of oil/water contact (OWC) with a porosity cutoff determined from porosity/permeability crossplots. Integration of the porosity-foot maps facilitated volumetric and spatial comparison with historic production data.
PC-derived crossplots were used to determine distribution and ranges of data that were in turn depicted as color-coded ranges on maps. Oil production and oil recovery per quarter section, initial production potential, and completion date for each well were mapped with this technique.
The main advantages of the mainframe were computational speed and high-quality graphics. However, complementary analysis with PC-based contour-mapping software provided similar results and served as an independent check for each mapping step.
PDC-Bit Performance Under Simulated Borehole Conditions
Authors: Andersen E. E. , Azar J. J. 
Published: December 2007

SummaryLaboratory drilling tests were used to investigate the effects of pressure on polycrystalline-diamond-compact (PDC) drill-bit performance. Catoosa shale core samples were drilled with PDC and roller-cone bits at up to 1, 750-psi confining pressure. All tests were conducted in a controlled environment with a full-scale laboratory drilling system. Test results indicate, that under similar operating conditions, increases in confining pressure reduce PDC-bit performance as much as or more than conventional-rock-bit performance. Specific energy calculations indicate that a combination of rock strength, chip hold-down, and bit balling may have reduced performance. Quantifying the degree to which pressure reduces PDC-bit performance will help researchers interpret test results and improve bit designs and will help drilling engineers run PDC bits more effectively in the field.
Inhibition of Gas Hydrates in Water-Based Drilling Muds
Authors: Kotkoskie T. S. , Al-Ubaidi Basil , Wildeman T. R. , Sloan E. D. 
Published: December 2007

Summary
A series of thermodynamic experiments were run on 16 simulated drilling muds and associated test fluids to improve the understanding of the equilibrium conditions for hydrate formation in water-based drilling fluids. Results indicated that, to a first approximation, the salt and glycerol contents of water in mud dominated hydrate formation. Other mud additives, such as bentonite, barite, and polymers, collectively promoted hydrate formation to a lesser degree.
Sources of Mercury and Cadmium in Offshore Drilling Discharges
Authors: Candler J. E. , Leuterman A. J. J. , Wong S-Y. L. , Stephens M. P. 
Published: December 2007

Summary
In 1988, the U.S. Environmental Protection Agency (EPA) proposed regulations that would set limits of 1.5 mg/kg mercury and 2.5 mg/kg cadmium for drilling-waste discharges. To determine potential sources of cadmium and mercury in drilling-waste discharges, samples of barite (barium sulfite), formation cores, and commercially available pipe-dope samples were analyzed for total and extractable levels of cadmium and mercury. From this analysis, most of the cadmium and mercury in drilling-fluid discharges are not available to the environment. The contribution of heavy metals from drilled formation solids is not known before drilling. End-of-pipe discharge limits on metals may compel drilling operators to assume that their wastes could fail the discharge limitation and thus ship all drilling wastes to shore.
Effect of Variable Saturation Exponent on the Evaluation of Hydrocarbon Saturation
Authors: Worthington Paul F. , Pallatt Nadla 
Published: December 2007

Summary
Petrophysical measurements on effectively clean, desaturated core plugs from different fields have shown that the assumption of a constant saturation exponent for a given sample frequently is violated, although the conventional bilogarithmic distribution of resistivity-index/water-saturation data is often approximately linear. These variations in saturation exponent are attributed to the effects of pore geometry, in particular the nonuniform distribution of electrolyte within a heterogeneous pore system as desaturation progresses. The data indicate that, if unrecognized, a variable saturation exponent can induce errors of more than 10 saturation units (s.u.) in the petrophysical evaluation of water saturation. Procedures are outlined for the identification of those physicochemical reservoir conditions that can give rise to a variable saturation exponent and for accommodating these variations in reservoir evaluation.
Computer File Format Standards
Authors: Thrasher T. S. 
Published: December 2007

Summary
The Pressure Transient Testing Technical Program Committee for the 1990 SPE Annual Technical Conference and Exhibition established a subcommittee in 1988 to investigate computer file standards for well-test data, type-curve libraries, and subroutine calls for program algorithms. This paper proposes a format standard for well-test data on floppy disks. The proposed format is adopted from the Canadian Well Logging Soc.’s (CWLS’s) Floppy Disk Committee for log data. The format, known as LAS (Log ASCII Standard), provides a data-file specification so that PC users have a flexible file format to store and retrieve large amounts of electronic instrument data from floppy disk quickly. Using this standard will give analysts direct access to the data they need for graphical analysis and computer-aided interpretation techniques. The LAS standard gives well-test service companies and operators a common floppy disk file structure to support the growing number of PC users who use PC-based pressure-transient analysis (PTA) programs.
Compatibility of Resin-Coated Proppants With Crosslinked Fracturing Fluids
Authors: Nimerick K. H. , McConnell S. B. , Samuelson M. L. 
Published: December 2007

SummaryThis paper describes the additive interaction and/or compatibility of various resin-coated proppants (RCP's) with low-, neutral-, and high-pH water-based fracturing fluids. Solutions are provided for those fluids exhibiting compatibility problems with RCP's.
Comprehensive Simulation of Horizontal-Well Performance
Authors: Economides Michael J. , Deimbacher Franz X. , Brand Clemens W. , Heinemann Zoltan E. 
Published: December 2007

Summary
The simulation of the performance of a horizontal well has generated certain new and important challenges. These include the partial penetration of the well in the horizontal direction within the allocated drainage area, the positioning of the well between the vertical boundaries, the distance from the parallel horizontal boundaries, and the permeability anisotropy. In addition, there are special problems in the simulation of the response of fractures (natural and induced) in regard to their contact with the well (longitudinal or transverse), their conductivity, and the conductivity distribution along the fracture.
We developed new numerical techniques to facilitate the simulation of these diverse problems. We use a locally refined perpendicular bisection grid to describe the horizontal (or deviated) wellbore. The grid is strictly orthogonal for the anisotropic case, and wellbore blocks are almost regular octagonal prisms. The transition to the coarse Cartesian grid is also orthogonal. The fully implicit formulation ensures the stability of the numerical solution. Our results are found to be in excellent agreement with published analytical or semianalytical approximations. In addition, the results offer flexibility that is not possible with analytical solutions. The grid system used is particularly amenable to handling practical problems with real reservoir geometries and configurations.
This paper presents a comprehensive numerical simulation of problems associated with horizontal wells, including the arbitrary positioning of the well within a fully anisotropic medium. Hydraulic or natural fracmres that intersect the well in the longitudinal or transverse direction are simulated for both infinite and finite conductivities.
The TLWP Cathodic Protection System
Authors: Evans Sheldon 
Published: December 2007

Summary
This paper details the subsea corrosion protection system of the tension leg well platform (TLWP), which comprises coatings and cathodic protection (CP). Postinstallation surveys reveal potentials of at least 150 mV more protective than the minimum potential required for protection. The TLWP protection system weighs 434, 000 lbm less than the conventional CP design, with 286, 000 lbm less on the floating portion of the TLWP.
Field Experience With an SRB Rapid Detection Test Kit
Authors: Horacek G. L. 
Published: December 2007

Summary
This paper reports field experience with a new rapid method to detect and count sulfate-reducing bacteria (SRB) accurately. Test results are available in 15 minutes, compared with the 3 to 4 weeks required with traditional culture methods. This new test method detects SRB that grow poorly or not at all on culture media and gives superior results with such solids samples as biofilms, soils, and sludge.
Effect of Foams Used During Carbonate Acidizing
Authors: Bernadiner M. G. , Thompson K. E. , Fogler H. S. 
Published: December 2007

Summary
Although acidization has been used successfully for many years to increase the productivity of petroleum wells in carbonate formations, demands on the performance and application of the acidizing process are increasing. This study investigated a method of in-situ foam generation that allows deeper wormhole penetration yet uses less acid than conventional methods. The dissolution patterns were imaged with neutron radiography, which provided an in-depth understanding of the effects of foam and other critical parameters. Results show that foam is effective in promoting efficient stimulation, even at low acid injection rates.
Waterflooding a Highly Stratified Reservoir
Authors: Warner Gary E. 
Published: December 2007

Abstract
This paper presents a review and analysis of a highly stratified Burbank sand waterflooding project in Osage County, Okla. Permeability values in this reservoir range from less than 0.1 md to nearly 3 darcys, and 90 percent of the permeability capacity is contained in approximately 26 percent of the reservoir volume.
To date, the project has recovered 103 bbl/flood-acre-ft since waterflood initiation, which represents 50 percent of the total preflood cumulative and 12 percent of the original stock-tank oil in place (OSTOIP). The outstanding feature of this project has been the economical recovery of a sizable quantity of oil at water-oil ratios higher than those normally considered prohibitive. Nearly 70 percent of the recovery to date has been achieved at water-cut values greater than 95 percent.
An ultimate waterflood recovery of 18 bbl/flood-acre-ft or 67 percent of the preflood recovery and 16 percent of the OSTOIP, is predicted. The ultimate primary and Secondary recovery will be 302 bbl/acre-ft and approximately 40 percent of the OSTOIP.
The actual performance is compared with the predicted performance by both the Stiles and the Dykstra-Parsons performance by both the Stiles and the Dykstra-Parsons methods, and applicability of these methods to this particular reservoir is evaluated. The performance of this particular reservoir is evaluated. The performance of this project indicates highly stratified reservoirs can be project indicates highly stratified reservoirs can be successfully and economically waterflooded when either reservoir or economic conditions preclude the use of mechanical and chemical means of mobility control.
Controlled Evaluation of a Surfactant in Secondary Recovery
Authors: Inks C.G. , Lahring R.I. 
Published: December 2007

Abstract
A surfactant waterflood, using a block copolymer of ethylene and propylene oxide (PLURONIC L64*), was started in 1956 in Kansas to determine the commercial feasibility of such a process. The production formation was the Bartlesville sand at a depth of 1,400 ft. Leases in the test area had attained both primary and secondary production peaks, and were on a normal decline when the production peaks, and were on a normal decline when the tests were initiated. The injection wells were taking water at a reasonable pressure and none of the operating conditions were particularly unusual. The leases were selected primarily because of normal operating conditions, and not primarily because of normal operating conditions, and not because of any serious problems demanding remedies. Oil production and water injection data were recorded during the 10-year test period, and their compilation indicates that the surfactant resulted in an increase of about 9 percent in secondary oil production. Other benefits derived from the surfactant injection were lower injection pressure that resulted in reduced power consumption and pressure that resulted in reduced power consumption and reduced erosion of the pumps; and lower calcium scale buildup. These fringe benefits more than offset the cost of the surfactant used.

Introduction
During the past several decades, considerable research has been carried out on secondary recovery of crude oil that remains in the producing formation despite the most efficient, current primary production practices. Methods are constantly sought of increasing recovery of oil, while at the same time improving the economic efficiency of operations.
One method that has received intensive study over the years is the use of a surfactant as a waterflood additive. Laboratory tests show conclusively that dilute solutions of surfactants remove considerably more oil from unconsolidated sand cores than does water alone. The loss of surfactant by adsorption at solid-liquid interfaces has caused serious doubt that surfactants can be used economically as waterflooding additives. This is especially true with anionic and cationic surfactants, and to a lesser extent with nonionic surfactants.
This work was undertaken to determine the effectiveness in increasing oil production by injecting water containing small quantities of a nonionic surfactant. The surfactant selected was PLURONIC L64*, a block copolymer based on ethylene and propylene oxide, having the following structure.