bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Comparison of Equation of State Tuning Methods
Authors: Merrill R. C. , Hartman K. J. , Creek J. L. 
Published: December 2007

Abstract
Equations of state find widespread use for their ability to describe a wide variety of reservoir fluid behaviour. However, this description is not usually obtained through a-priori predictions. The parameters of the equation of state (EoS) often need adjusting (tuning) before yielding usable reservoir predictions. During tuning, the parameters of the EoS are adjusted to make the predictions match a variety of experimental data.
As part of an industrial joint-venture, three Peng-Robinson equation of state models were developed to describe a single set of phase behaviour and PVT data. The EoS models were developed independently, and their variety illustrates the different techniques available for this purpose. This paper concentrates on: the differences in each of the development processes, the resulting match, and the effect this has on a-priori slim-tube predictions. The paper examines the rationale behind the choices made during development.
The three methods share many similarities in their execution, however, there are some pronounced differences. These differences are most obvious in the treatment given to the different classes of experimental data during EoS development. Despite these differences, the models were all suitable for reservoir development purposes, which leads to the conclusion that consistency in the application of a technique is more important than the technique itself.
The co-operative nature of this work serves as a successful illustration of the inherent strength of joint ventures. The participating companies have used this cross-fertilisation to ensure the technical integrity of their methods.
Combustion Performance in the Countess Project
Authors: Tzanco E. T. , Moore G. R. , Good W. K. 
Published: December 2007

ABSTRACT
A combustion project in the Countess Β pool of Southeastern Alberta was performed between 1983 and 1992 in two phases: the first phase, the pilot, essentially a dry normal-air injection combustion, and the second phase, the expansion, a water alternating with air (WAA) injection. Both projects were concurrent with a waterflood. The objective of the project was to assess the technical and economic feasibility of combustion for commercial application in the Countess-Lathom trend, which is characterized by an 28°API oil and medium pressures (9.6 MPa). This paper describes a performance evaluation of the pilot and the expansion projects. Well-monitoring techniques and four methods that were utilized to estimate the incremental oil recovery from the fireflood wells are also discussed.
The Countess Β pilot project was a technical success, with an incremental oil recovery of 9% of the pilot original oil in place (OOIP), but the recovery from the expansion project was lower than had been expected, based on combustion tube laboratory experiments. Although the expansion was successfully ignited, the combustion shifted to a low temperature mode. An increase in barite scale, a problem already present in the area was detrimental to production. An incremental oil recovery of 3% of the expansion OOIP was obtained before the project was shut down. It was concluded that both combustion schemes were not robust enough to give confidence for future application in the Countess Lathom pools.
New Solutions for Wells With Finite-Conductivity Fractures Including Fracture-Face Skin: Constant Well Pressure Cases
Authors: Liao Yizhu , Lee W. J. 
Published: December 2007

ABSTRACT
This paper presents new solutions for wells with finite- conductivity fractures including fracture-face skin damage under constant well pressure production. Fracture storage is also included. An infinite-conductivity fracture is included as a limiting case. The new solutions are obtained numerically by modeling a well with an elliptical finite-conductivity fracture in an infinite-acting reservoir. The new solutions are as accurate as other published solutions, which are available only for cases without fracture-face skin damage. The new solutions presented in this paper can be used to analyze, history match, and predict production data for wells with finite-conductivity fractures including fracture-face skin damage and fracture storage under constant well pressure production. Examples are provided.
Field Demonstration of the Electrofrac Heatflood Process
Authors: Vossoughi Shapour , Sarapuu Erich , Crowther R. H. 
Published: December 2007

Abstract
This paper will present the results of a field demonstration of a less known enhanced oil recovery process named Electrofrac Heatflood process. The process entails the use of down-hole electrodes mounted in the oil sand, a specially configured electric power unit, and facilities for injecting air and fuel into a controlled combustion zone within the area stimulated. One essential feature is creation of electrically conductive paths within the oil sand. This is accomplished in either, or both of two mutually supportive ways: (1) electrocarbonization of a small portion of the oil present between electrodes mounted in the oil sand and (2) injection of electrically conductive pellets with, or in place of the sand normally injected during hydrofracing as part of the original well completion. The process has been field tested successfully for the typical largely heterogeneous oil sands found in predominately fluvial deltaic formations. Field test was initially performed during 1979 and 1980 on a lease named Beachner-1 located in the east-central portion of Neosho County, Kansas and again in 1983 to 1985 expanded to Beachner-1 and Beachner-2. The oil reservoir at the location is shallow and generally unproductive with essentially no natural driving pressure, and natural flow is typically just 1 to 3 gallons per day per well from about twenty feet of pay sand.
During the initial field test, an enhancement ratio of 4.5 to 5.4 was achieved relative to natural production, even though the field was only partially stimulated Observed enhancement ratio during the second field test ranged from 4.6 to 10.7. And the enhancement ratio at the other more remote wells ranged from 1.8 to 3.1 giving overall enhancement ratios of 2.4 to 5.5 for all wells then on the lease at that time. Increased production was sustained for more than two years through partial stimulation of the field containing fifty wells. The neighboring leases to the south also benefitted indirectly from the stimulation on the Beachner-1 and Beachner-2 leases.
The Electrofrac Heatflood process facilities included a specially outfitted 500 KVA diesel electric generator, electrodes mounted down-hole in the oil sand, air and fuel injection facilities, and proprietary means for distributing electric energy deep into the oil sand to promote heat cycles through controlled combustion within patterns of injection and production wells.
The process has been proven to be an effective recovery technique for those reservoirs that because of nature of their heterogeneity the conventional recovery techniques fail.
WAG Flow Mechanisms in Presence of Residual Oil
Authors: Minssieux Louis , Duquerroix J-P. 
Published: December 2007

ABSTRACT
Dry gas/water injections were performed under immiscible conditions in a water-wet 80 cm long sandstone, to analyse unidimensional aspects of water alternating gas (WAG) process in porous media.
Experiments were conducted under tertiary conditions at constant flow-rate, with a continuous pressure regulation in the gas injected cell, maintained at the pressure reached during each imbibition step, prior to any drainage period. Residual oil was a crude saturated or not with methane to determine the influence of swelling.
A modelling of several of these laboratory experiments is also presented, taking into account oil swelling and gas relative permeability hysteresis. The typical mechanisms of WAG flow in porous medium are highlighted and the simulations are shown to reproduce these features as well as extra oil production.
A Reservoir Model for Landfill Gas Projects
Authors: Fair A. R. , Maurer R. J. , Fair W. B. 
Published: December 2007

Abstract
In recent years there has been an increased interest in unconventional fuel sources, including the production of natural gas from organic decomposition of landfill waste material. This interest is not solely a result of the energy shortages which climaxed with the energy crisis of 1973. Capture and utilization of gas from biomass decomposition dates at least as far back as 18591. The unconventional fuel source addressed by this paper is methane gas from landfills.
Although petroleum engineers are usually not involved in landfill projects, the evaluation of gas reserves and production performance of these projects involves the use of reservoir engineering techniques, which must be modified to model the unique characteristics of these projects. This paper discusses the unique characteristics of landfill gas projects and shows how simple material balance and pressure transient models can be developed and applied to the evaluation of landfill gas projects.
Undersea Fiber Optic Technology for the Offshore Community
Authors: Mariano J. J. 
Published: December 2007

ABSTRACT
The explosive growth in demand for global communications has been met by a rapid evolution in the undersea fiber-optic technology, which in just a few years has become the predominant method of communication across the world's oceans and seas. As the scope of applications has become broader, the technology has become more diverse, and now comprises a range of products capable of providing economical, reliable service in any subsea environment, from ocean depths to coastal lagoons.
In this paper, we discuss how undersea lightwave technology is being applied to meet the communication and production control needs of the offshore oil and gas industry. We discuss the trends and technology developments that are changing the economics of undersea fiber-optic communication networks, as well as synergies in the offshore industry. We consider various applications for the industry and means of enhancing the profitability of platform operations through reduced downtime, reduced operating cost, and enhanced safety. Finally, we discuss extensions to exploratory drilling and land-based operations.
Use of the Dual-Screen Thru-Tubing Sand Control Method
Authors: Freiman O. H. , Johnson K. J. 
Published: December 2007

ABSTRACT
This paper will describe a new sand control method used in an area of Ecuador, South America where workover rigs are not readily available. Sand production had been significantly affecting maintenance costs on surface and downhole production equipment and had impacted performance of the downhole jet pump, subsequently causing a decrease in well production. By installing a small-diameter, sintered metal gravel-pack screen across the perforation interval and placing the gravel-pack sand with coiled tubing, the sand production was successfully controlled. The procedure and equipment used to perform this technique as well as post job data that provide results obtained will also be presented. Noteworthy advantages, such as recompletion without removal of the existing production completion string and without use of a workover rig, will also be discussed.
A General Formulation for Compositional Reservoir Simulation
Authors: Rodriguez Fernando , Galindo-Nava Agustin , Guzman Javier 
Published: December 2007

ABSTRACT
In this paper we present a general formulation to solve the non-linear difference equations that arise in compositional reservoir simulation. The general approach here presented is based on Newton's method and provides a systematic approach to generate several formulations to solve the compositional problem, each possesing a different degree of implicitness and stability characteristics. The Fully-Implicit method is at the higher end of the implicitness spectrum while the IMPECS method, implicit in pressure-explicit in composition and saturation, is at the lower end.
We show that all methods may be obtained as particular cases of the fully-implicit method. Regarding the matrix problem, all methods have a similar matrix structure; the composition of the Jacobian matrix is however unique in each case, being in some instances amenable to reductions for optimal solution of the matrix problem. Based on this, a different approach to derive IMPECS type methods is proposed; in this case, the whole set of 2nc + 6 equations, that apply in each gridblock, is reduced to a single pressure equation through matrix reduction operations; this provides a more stable numerical scheme, compared to other published IMPECS methods, in which the subset of thermodynamic equilibrium equations is arbitrarily decoupled from the set of gridblock equations to perform such reduction.
We discuss how the general formulation here presented can be used to formulate and construct an adaptive-implicit compositional simulator. We also present results on the numerical performance of FI, IMPSEC and IMPECS methods on some test problems.
Experimental and Mathematical Modeling of Helical Buckling of Tubulars in Directional Wellbores
Authors: Salies J. B. , Azar J. J. , Sorem J. R. 
Published: December 2007

ABSTRACT
Experimental testing of helical buckling of tubulars, using three different test facilities, is presented and discussed. The tests provide information to better understand the buckling behavior of circumferentially restrained tubulars. The finite element method is used in the analysis of helical buckling, allowing inclusion of friction during the development of the helix. There was an excellent agreement between the finite element solution and the experimental results.
Big Mineral Creek Barnes Unit - A Successful Water Injection Pressure Maintenance
Authors: Alderman J.H. 
Published: December 2007

Abstract
A successful water injection pressure maintenance operation has been in progress in the Big Mineral Creek (Barnes sand) field, Grayson County, Tex., since Aug., 1962. The Barnes sand is typical of many fields in North Texas in that it is composed of several separate sand bodies operated as a single reservoir. one of the objectives, therefore, in planning the supplementary recovery operation was to insure maximum hydrocarbon recovery from each of the five sands which constitute the Barnes reservoir.
To insure this, a stage flood was initiated in which injection and production was confined to the lower sand member initially. When the flood front was sufficiently advanced, the next shallower zone was opened for production and injection. This procedure will be repeated until all five zones are effectively flooded out.
Introduction
The Big Mineral Creek (Barnes sand) field is typical of many fields in the North Texas area in that it is composed of a number of individual sand bodies which are in reality individual reservoirs and which have been grouped together and classified as a single field. This type of grouping did not offer any major production problems during the primary production portion of the reservoir's history. production portion of the reservoir's history. However, early in the life of the field it was realized that a pressure maintenance project would be desirable in the Barnes sand, and a plan of operation would be needed which would plan of operation would be needed which would maximize production from each individual sand member. Experience in other fields of this type had shown that, unless some type of selective injection was initiated, water breakthrough could occur in one of the minor sand intervals with better permeability. Corrective measures later in the life of the flood, if this sand was located in the center of the interval, could be costly.
GEOLOGY
The Big Mineral Creek area is located as shown in Fig. 1 on the west side of Marietta syncline and on the eastern flank of the Walnut Bend platform in Grayson County, Tex. This area is composed of a stratigraphic series of sandstone reservoirs which include the Barnes sand. The Barnes reservoir was established by field rules as a stratigraphic interval existing between the approximate depths of 4,900 and 5,200 ft. Contained within the Barnes interval are five correlative sand bodies that are lithologically characterized as fine to medium grained sandstones containing traces of chert. A type log of this interval is shown in Fig. 2. These zones comprise the basal portion of the upper Des Moines strata.
Analysis Method for Contact Forces Between Drillstring-Well-Riser
Authors: Bueno R. C. S. , Morooka C. K. 
Published: December 2007

Abstract
This paper proposes a methodology(1) to estimate the contact forces generated by the drillstring against the wellbore and the marine drilling riser system. A new procedure for overall analysis of the drill string behavior inside the riser and wellbore is described.
This is important in the safety analysis of the wellhead equipment and also in planning drilling operations. The results also suggest that the forces should be used in the dynamic analysis of marine riser system.
Coiled Tubing Drilling on Lake Maracaibo
Authors: Adamson S. J. , Rodriguez A. , Leising L. J. 
Published: December 2007

Abstract
Drilling through shallow gas zones can be a major hazard, especially in offshore operations. An innovative technique using tender-assisted coiled tubing (CT) drilling is presented, which allows the determination of hazardous shallow gas presence with minimum risk, prior to mobilization of a large drilling barge. One advantage of the use of CT drilling is in increased safety because there are no personnel on the platform while drilling as the barge is kept 1 50 ft. away from the platform. Should a shallow gas flow occur, the gas is diverted with only minimal equipment exposed to damage and no danger to personnel.
The technique of tender-assisted coiled tubing drilling has been used to drill five 3-7/8 in. slim hole wells in Lake Maracaibo, Venezuela. Equipment, techniques, and safety merit to perform the drilling operation are described. The successful multiwell campaign has provided
References and illustrations at end of paper a drastic improvement in safety while significantly reducing top-hole drilling costs. With the learning curve progress allowed by a multiwell program, it is demonstrated that drilling rates with CT can exceed those of conventional rotary drilling.

Applications
This technique is applicable to many shallow gas problems both on land and offshore.

Technical Contributions
Risk Analysis Theory Applied to Fishing Operations: A New Approach on the Decision-Making Problem
Authors: Cunha J. C. S. 
Published: December 2007

Abstract
In the past the decisions concerning whether to continue or interrupt a fishing operation were based primarily on the operator's previous experience(1). This procedure often led to wrong decisions and unnecessary loss of money and time.
This paper describes a decision-making method based on risk analysis theory and previous operation results from a field under study. The method leads to more accurate decisions on a daily basis allowing the operator to verify each day of the operation if the decision being carried out is the one with the highest probability to conduct to the best economical result. An example of the method application is provided at the end of the paper.
Effects of Porosity and Permeability on In-situ Combustion Fuel Consumption
Authors: Couch Earl J. , Rodriguez Harold V. 
Published: December 2007

Abstract
This paper presents a method for estimating field fuel consumptions by adjusting laboratory in-situ combustion fuel consumption data for the effects of formation porosity and permeability. permeability. Results from combustion experiments were used to establish the reaction kinetic and heat loss parameters in an in-situ combustion model. After attaining satisfactory agreement between calculated and experimental results, both for unconsolidated and consolidates media, the model was used to calculate the effects of changes in porosity and permeability on the fuel consumption. Calculations were made for a wide range of crude oil viscosities. The study showed that porosity and permeability have marked effects on fuel consumption, and that these effects depend on the crude oil viscosity.
Introduction
In-situ combustion has become an important process for oil recovery. Successful process for oil recovery. Successful engineering of one of these projects depends on the estimate of the fuel concentration, which determines air requirements for propagation of the combustion front. Air requirements can critically affect the technical and economic prospects for an installation. prospects for an installation. Because of the importance of fuel concentration to the process, many studies aimed at correlating fuel with the various chemical physical and operating parameters of the physical and operating parameters of the system have been made. These attempts have not produced generally applicable correlations. Consequently, current practice in estimating fuel for a particular field prospect involves laboratory experimentation to characterize the system. Commonly a combustion tube run provide an estimate of the fuel concentration under laboratory conditions. This value may be corrected for various field operating condition which differ from those in the laboratory, such as pressure or gas flux.
Two parameters which should affect the fuel, but whose effects have been treated only briefly in the literature, are permeability and porosity. Alexander, Martin and Dew found that porosity. Alexander, Martin and Dew found that with a 21.8 degrees API crude oil., crushed Curtis core gave essentially the same fuel availability as consolidated Crutis core, and that an Ottawa sand pack gave essentially the same fuel availability as a consolidated Berea core. Moss, White and McNiel presented two combustion tube runs which gave fuel values closely comparable to field test results. Theoretical papers make no direct mention of the effects papers make no direct mention of the effects of permeability and porosity on fuel concentration.
Fractal Distributions of Reservoir Properties and Their Use in Reservoir Simulation
Authors: Berta Dominique , Hardy H. H. , Beier R. A. 
Published: December 2007

Abstract
Geostatistics has become a popular way to distribute reservoir properties between wells. One of the geostatistical methods being used is fractal geostatistics. Most porosity well logs have been found to have a fractal character. An analysis of vertical and horizontal logs, core photos, and outcrop photos has led to a rather simple model to describe porosity and permeability distributions. This representation has been tested in reservoir simulation of a mature waterflood and found to match production history with very little history matching. Fractal distributions were found to require much less history matching than classical layer cake models. Conoco is now actively applying this new technology to a number of its reservoirs.
New Polymer/Surfactant Systems for Stabilizing Troublesome Gumbo Shale
Authors: Alonso-Debolt M. A. , Jarrett M. A. 
Published: December 2007

Abstract
With increasing environmental regulations on the use of oil-based (or synthetic-based) invert emulsion drilling fluids, options for designing more inhibitive water-based drilling fluids with greater versatility are being explored. The challenge set for water-based drilling fluid technology is to meet the same performance expectations of oil-based drilling fluids, particularly for improving shale stabilization.
This paper discusses the development and application of water-based polymeric mud systems that incorporate new chemical classes of surfactants. These new zwitterionic surfactants demonstrate unique synergistic benefits with polymers for improving shale stabilization.