bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modeling and Design of Jet Pumps
Authors: Hatzlavramidis D. T. 
Published: December 2007

Summary
Models for jet pumps currently are derived under the assumption that the power and well fluids are incompressible liquids that, in many cases, are assumed to have equal densities. When either the well or the power fluid contains gas, current design practices still use the equations for incompressible liquids and account for the presence of gas by modifying the mass-flow-rate ratio and the friction-loss coefficients. This paper proposes a new approach to modeling pumps operating under multiphase-flow conditions.
Use of Low-Shear Pumps and Hydrocyclones for Improved Performance in the Cleanup of Low-Pressure Water
Authors: Flanigan David A. , Stolhand James E. , Shimoda Elwyn , Skilbeck Frank 
Published: December 2007

Summary
Although the advantages of using hydrocyclones for oily water cleanup are well proven, their use has been limited to applications where adequate system feed pressure for satisfactory operation was present. To use hydrocyclones in low-pressure operations, research testing was undertaken to determine the most suitable pumping system. Successful field trials with a low-shear progressive cavity pump and a single-liner hydrocyclone were conducted in the U.S. These trials provided the basis for full-scale tests on the Hutton platform in the U.K. sector of the North Sea. These tests demonstrated the feasibility of using large, low-shear, progressive cavity pumps in conjunction with multitube hydrocyclone units. A long-term evaluation of the pumped system was completed on the Hutton platform following these reported results. This work not only demonstrated the feasibility of pumped hydrocyclone oily water cleanup systems, but also resulted in analytical techniques that greatly assist in optimizing hydrocyclone operation.
A New Caustic Process for Softening Produced Water for Steam Generation
Authors: Jan R. J. , Reed T. G. 
Published: December 2007

SummaryOilfield produced water containing a high concentration of total dissolved solids (TDS) and hardness can successfully be softened for use as oilfield steam-generator feedwater. At the Belridge field in Kern County, CA, the combination of caustic softening and weak-acid cation exchange has been used to soften produced water containing 11, 000 TDS and 550-ppm hardness to &lt; 1-ppm hardness. The resultant sludge containing calcium carbonate and magnesium hydroxide is concentrated by centrifuging and is disposed of in a landfill. Compared to the use of conventional strong-acid ion exchange followed by weak acid or weak acid followed by weak-acid ion exchange systems, the process offers the benefits of lower capital and chemical costs, partial silica removal, and elimination of liquid waste discharge. This paper gives design parameters and operating conditions and discusses future applications in thermal recovery projects.
Modeling Pressure-Transient Behavior of Sectionally Homogeneous Reservoirs by the Boundary-Element Method
Authors: Kikani Jitendra , Horne Roland N. 
Published: December 2007

Summary
Pressure-transient solution in a piecewise homogeneous reservoir with arbitrary geometry of each region is proposed by the Laplace domain boundary-element method (BEM). Any number of such regions with different rock and fluid properties can be included in the solution procedure. This formulation can solve for impermeable barriers of any shape, size, and orientation, including large pressure-support sources (aquifers) and fluid-injection problems that show composite behavior. Any number of line-source wells can be included. Example solutions are verified against known analytical solutions. Injection-fluid-front velocity is calculated as part of the solution; thus, the fluid fronts can be tracked in a quasistationary sense. The analytical aspects of this procedure are discussed. BEM solutions are accurate because the method retains the free-space Green's function of the governing differential operator as a global weighting function in the integral equation.
A New Front-Tracking Method for Reservoir Simulation
Authors: Bratvedt Frode , Bratvedt Kyrre , Buchholz C. F. , Holden Lars , Holden Helge , Risebro N. H. 
Published: December 2007

Summary
This paper presents a new numerical method for solving saturation equations without stability problems and without smearing saturation fronts. A reservoir simulator based on this numerical method is under development. A set of test problems is used to compare the simulation results of the new simulator with those of an existing finite-difference simulator (FDS).
The Averaging Process in Permeability Estimation From Well-Test Data
Authors: Oliver Dean S. 
Published: December 2007

Summary
Permeability estimates from the pressure derivative or the slope of the semilog plot usually are considered to be averages of some large ill-defined reservoir volume. This paper presents results of a study of the averaging process, including identification of the region of the reservoir that influences permeability estimates, and a specification of the relative contribution of the permeability of various regions to the estimate of average permeability. The diffusion equation for the pressure response of a well situated in an infinite reservoir where permeability is an arbitrary function of position was solved for the case of small variations from a mean value. Permeability estimates from the slope of the plot of pressure vs. the logarithm of drawdown time are shown to be weighted averages of the permeabilities within an inner and outer radius of investigation. The estimate is shown to be influenced most strongly by permeabilities at a distance r=0.015(k¯t/ϕμct)½[5.6×10−5]. Fully 50% of the contribution to the permeability estimate is from the reservoir volume in the range from r=0.011(k¯t/ϕμct)½[4.1×10−5] to r=0.022(k¯t/ϕμct)½[8.1×10−5]. An analytic expression for the weighting function is derived in this paper.
Temperature Data for Optimizing Cementing Operations
Authors: Tllghman S. E. , Benge O. G. , George C. R. 
Published: December 2007

Summary
Cement slurries must be designed for the downhole conditions at the time of the cement job. Of all the factors that influence cement slurry design, bottomhole circulating temperature (BHCT) is potentially the most important element. Measurement of BHCT, the temperature within the wellbore that accounts for the cooling effects of fluid circulation, is not a standard field procedure for several reasons. A recently developed tool, however, simplifies temperature measurement under true circulating conditions. The new temperature recorder allows BHCT to be measured under normal operating conditions. The electronic memory recorder is dropped down the drillstring or lowered by wireline/slickline. When the tool is retrieved, the recorded data are transferred to a personal-computer disk. With this temperature information, the cement slurry can be designed with a high degree of confidence. This paper describes the temperature-recording memory gauge, its features, and its operation. Examples of data collected under field conditions illustrate its application.
Method To Quantify Viscosity Effects on Dispersion Test Improves Testing of Drilling-Fluid Polymers
Authors: Hale A. H. 
Published: December 2007

Summary
Many of the available polymers are claimed to inhibit cuttings dispersion effectively. The experiments done to support these claims show the effectiveness of the polymers in inhibiting dispersion of sized shale through the hot rolling dispersion test. One of the most significant factors in this test is the viscosity of the test fluid. The fluid viscosity can create the illusion that a particular product effectively inhibits cuttings dispersion. A method is presented in which the dispersion-inhibiting effect of viscosity can be subtracted from the amount of shale retained to obtain a more accurate determination of the effectiveness of a drilling-fluid additive to inhibit cuttings dispersion. A comparison is presented that clearly demonstrates that the partially hydrolyzed polyacrylamide (PHPA) polymer is the best available polymer to inhibit cuttings dispersion cost-effectively.
Gas-Influx Detection With MWD Technology
Authors: Bryant T. M. , Grosso D. S. , Wallace S. N. 
Published: December 2007

SummaryThis paper describes a new gas-influx detection technique that monitors the acoustic responses of annular measurement-while-drilling (MWD) pulses to provide a rapid, early warning of the development of potential gas-kick situations. The technique has been evaluated in both water- and oil-based muds during about 40 gas-kick simulations at two full-scale testing facilities. Free gas is identified by amplitude attenuation and phase delay of MWD fundamentals and their harmonic frequencies. Detection is independent of influx location because the entire length of the annulus between the bit nozzles and a surface-pressure transducer is sampled. Detec tion of potential gas-kick situations generally occurred within minutes of influx initiation, before any significant gas expansion.Some tests also evaluated a downhole MWD mud-resistivity sensor. Results indicated that both these techniques, and particularly the pulse acoustics, can provide unequivocal confirmation of gas and an earlier warning of gas-kick situations than conventional kick-detection techniques.
Simulation of Block-to-Block Processes in Naturally Fractured Reservoirs
Authors: Fung Larry S.-K. 
Published: December 2007

SummarySimulation of fractured reservoirs with the dual-porosity/dual-permeability approach involves discretization of the solution domain into two collocated continua called the matrix and the fracture. The original idealized model assumes that the matrix acts essentially as a source or sink to the fracture, which is the primary conduit for fluid flow. In multiphase flow situations, this idealization was found to be inadequate. Enhancements are needed to represent the local matrix/fracture and matrix/matrix drainage and imbibition processes. Attempts to represent these processes include the gravity-segregated model, the subdomain model, the pseudofunction method, and the dual-permeability model.This work examines the mechanisms involved in gas/oil gravity drainage in terms of the block-to-block process. Current methods for treating this problem are reviewed to identify deficiencies. A new approach is proposed in which these mechanisms can be represented properly in the field-scale simulation of these reservoirs. The method involves the calculation of pseudo capillary potentials, which in an average sense (on a computational block basis) give the correct flow behaviors. These pseudos can be calculated a priori if a vertical equilibrium (VE) assumption can be made about the fluid distribution in the matrix blocks. When the VE assumption is not valid, the pseudos can be determined from fine-grid simulations.
Small-Particle-Size Cement
Authors: Ewert D. P. , Almond S. W. , Bierhaus W. M. 
Published: December 2007

Summary
Successful remedial cementing has historically been difficult in wells with large-interval, multizone, gravel-packed completions. The reason is the inability of conventional oilfield cements to penetrate gravel packs adequately. Small-particle-size cement (SPSC) was developed to penetrate gravel packs and to provide the zonal isolation required. This paper details the laboratory work, job design, and field implementation of this new cement.
Field Testing of Variable-Speed Beam-Pump Computer Control
Authors: Guffey C. G. , Rogers J. D. , Hester L. R. 
Published: December 2007

Summary
A variable-frequency drive (VFD) used to change the speed of beam-pump motors was tested on seven wells to control the rate of oil pumping. Increased power consumption was observed, but on certain wells, increased production rates can result in overall benefits.
A Model Describing Steam Circulation in Horizontal Wellbores
Authors: Arthur J. E. , Best D. A. , Lesage R. P. 
Published: December 2007

Summary
A model to evaluate heat losses, steam quality, and pressure profiles during steam circulation in a horizontal wellbore was developed. The model simulates countercurrent flow stream and accounts for the interactions of heat transfer, fluid flow, phase changes, slippage between steam and water, and flow regime changes. Development of this model arose from a need to determine the wellbore heat-loss distribution during the warm-up phase in Mobil Oil Canada's (Mocan's) horizontal well at Cold Lake. Results from the model were verified with actual field data.
Feasibility of Cyclic CO2 Injection for Light-Oil Recovery
Authors: Thomas G. A. , Monger-McClure T. G. 
Published: December 2007

SummaryField performance trends are presented for cyclic CO2 injection in light-oil sandstone reservoirs. Results indicate that the mass of CO2 injected is the best predictor of stimulated oil production rate and ultimate incremental recovery. The correlations enhance understanding of the single-well process, improve reservoir selection criteria, and suggest operational guidelines.
Permeability Modification Simulator Studies of Polymer-Gel-Treatment Initiation Time and Crossflow Effects on Waterflood Oil Recovery
Authors: Gao Hong W. , Chang Ming-Ming , Burchfield Thomas E. , Tham Min K. 
Published: December 2007

SummaryA 3D, three-phase (oil/water/gas) permeability modification simulator was developed by incorporating an in-situ gelation model into a black-oil simulator (BOAST). Several important features that describe gel-system transport in a porous medium were considered. Simulation results showed that the effectiveness of a gel treatment in either an injection or production well or in an injection and a production well together decreased as kV/kH increased. The best gel treatment initiation time in the injection well only or the injection and production wells together was approximately when water breakthrough occurred. The new simulator is useful to simulate and to optimize any combination of primary production, waterflooding, polymer flooding, and permeability modification treatments.
Oil Recovery by Imbibition in Low-Permeability Chalk
Authors: Cuiec Louis , Bourbiaux Bernard , Kalaydjian François 
Published: December 2007

SummaryThis paper describes experimental studies of spontaneous imbibition of oil by water in a low-permeability outcrop chalk. At constant and high interfacial tension (IFT), the importance of capillary forces and the existence of a predominantly countercurrent mechanism were established. Additional experiments were performed to investigate the influence of length and of various boundary conditions. In another investigation, we modified the IFT at the sample boundary by using pairs of conjugate phases of the w-hexane/ethanol/brine ternary system. Final recovery increased when IFT was lowered. We give a numerical interpretation for this last result.
Proper Nozzle Location, Bit Profile, and Cutter Arrangement Affect PDC-Bit Performance Significantly
Authors: Garcia-Gavito Daniel , Azar J. J. 
Published: December 2007

SummaryAn experimental study comparing the effects of polycrystalline-dia-mond-compact (PDC) -bit design features on the dynamic pressure distribution at the bit/rock interface was conducted on a full-scale drilling rig. Results showed that nozzle location, bit profile, and cutter arrangement are significant factors in PDC-bit performance.
New Technologies Address the Problem Areas of Coiled-Tubing Cementing
Authors: Carpenter R. B. 
Published: December 2007

Summary
Coiled-tubing cementing has been practiced successfully on the Alaskan North Slope for several years. This paper discusses the special problems faced when this technology was applied to offshore U.S. gulf coast operations. The innovative solutions and procedures developed to improve the economic and technical success of coiled-tubing cementing are also discussed. Comparative laboratory and computer studies, as well as field case histories, will be presented to show the economic merit of this technology.
A Practical Approach to Drilling-Fluid Surveillance and Management
Authors: McLane M. A. , Medley G. H. 
Published: December 2007

Summary
Since the mid-1980's, Exxon Co. U.S.A. has used low-solids, polymer-extended (LSPE) drilling fluids extensively in its Rocky Mountain operations. These muds, combined with good surveillance and management, have improved drilling performance and reduced costs significantly. This paper summarizes our experience with LSPE muds and describes surveillance techniques developed to optimize drilling performance. It also reviews guidelines for maintaining these muds and discusses limitations on their use. Case histories from three Wyoming field areas are included for background data. These field data are used to describe the evolution of LSPE mud surveillance tools and to illustrate the benefits of using an LSPE mud system. Potential problems that may occur when these muds are used also are discussed.
Application of Freshwater and Brine Polymer Flooding in the North Burbank Unit, Osage County, Oklahoma
Authors: Moffitt P. D. , Zornes D. R. , Moradi-Araghi Ahmad , McGovern J. M. 
Published: December 2007

Summary
A freshwater polymer-flood project was implemented in a 1, 440-acre area of the North Burbank Unit (NBU) in 1980 with sequential injection of 4.2 million lbm of polyacrylamide and 4.0 million lbm of a 2.9% aluminum citrate crosslinking solution. Response to polymer flooding has been very pronounced, with ultimate incremental oil recovery projected to exceed 2.5 MMSTB of oil and total project oil expected to be 4.5 MMSTB. A crosslinked polymer-flood process for use in brine was developed that displays equally favorable performance characteristics as the freshwater polymer-flooding system.
Measurement and Computation of Near-Critical Phase Behavior of a C1/nC24 Binary Mixture
Authors: Bjorlykke Ole P. , Firoozabadi Abbas 
Published: December 2007

Summary
Equations of state (EOS) satisfactorily predict phase behavior and density of reservoir fluids outside the retrograde and near-critical regions. Predictions in these regions, however, are an unresolved problem. A first step to improve the understanding of retrograde and near-critical regions would be to measure the phase behavior of well-defined binary hydrocarbon mixtures of very different molecular sizes. This paper reports measurements on a C1/nC24 binary mixture with a wide retrograde and critical region. Measured dewpoints are in the range of 12, 000 to 15, 500 psia [82.74 to 106.8 MPa]. Retrograde liquid volumes and gas densities at three different temperatures were measured. Liquid phase compositions and densities also were measured on a selective basis. Conventional use of the EOS failed to predict the phase behavior of the model binary system. The data will be useful in modifying the EOS in the retrograde and near-critical regions.
Brassey Oil Field, British Columbia: Development of an Aeolian Sand—A Team Approach
Authors: Woofter D. M. , MacGillivray John 
Published: December 2007

Summary
This paper presents a case study of how an aggressive engineering/geoscienceteam approach provided the development plan for the Brassey oil field. Miscibleflooding of the field began only 2 years after discovery. The geological andgeophysical technical contribution to field development are emphasized.
Estimation of Radial Permeability Distribution From Well-Test Data
Authors: Oliver Dean S. 
Published: December 2007

Summary
This paper presents a method of estimating a radial permeability distribution that would reproduce the pressure data obtained in a well test. The method is applied to three examples: permeability variation in a composite reservoir, porosity variation in a composite reservoir, and permeability variation with inaccurate data. The permeability estimates obtained are shown to be smoothed versions of the actual permeability distribution, and an estimate for the resolution width of the smoothing is provided. One significant advantage of the solution method applied in this paper is the ability to estimate permeability variation without dividing the reservoir into zones of constant permeability.
State-of-the-Art Simultaneous Downhole Flow-Rate and Pressure Measurement Equipment
Authors: Haws G. W. , Knight B. L. 
Published: December 2007

Summary
Development of simultaneous downhole flow-rate/pressure measurement equipment has permitted better determination of reservoir properties. Application of such equipment to layered reservoirs allows determination of individual layer properties. This paper reviews state-of-the-art pressure and flow-rate devices, discusses the advantages and limitations of specific equipment, and addresses the need to evaluate current tools and areas for future research.
Proton Magnetic Resonance and Pore Size Variations in Reservoir Sandstones
Authors: Howard James J. , Kenyon William E. , Straley Chris 
Published: December 2007

Summary
Proton nuclear-magnetic-resonance (NMR) longitudinal relaxation time, T1, in water-saturated sandstones is related closely to pore size distributions. Most of the sandstones shown in this paper exhibit a relatively narrow T1 distribution curve, corresponding to a rather narrow distribution of the large pores visible by optical microscopy of thin sections. The surface relaxivity, ρ, which scales NMR T1 into pore size, is evaluated by comparing mean T1 for each sample with average pore diameter and volume/surface area data obtained from digitized thin sections. Permeability estimated from NMR parameters closely approximates measured permeability for these samples. These permeability estimates are closer than the variations in surface relaxivity would predict. This apparent contradiction results from parallel effects on the permeability and proton relaxation by clays in the pores.
Field Application of a Method for Interpretation of Horizontal-Well Transient Tests
Authors: Shah Piyush C. , Gupta Deepak K. , Singh Lehmbar , Deruyck Bruno G. 
Published: December 2007

Summary
In a multitransient test in the Bombay High field offshore India, simultaneous measurement of downhole pressure and flow rate enables identification of early- and late-time pseudoradial-flow regimes and intermediate linear flow. Analysis of these successive flow regimes yields estimates of the anisotropic formation permeabilities and the mechanical skin factor. In a second interpretation step, these estimates are refined through a weighted, nonlinear least-squares history match of either the measured transient-wellbore-pressure or the flow-rate data. An algorithm is presented to compute the well rate from transient pressure, given the characteristic response model of the single-well system.
A Unified Model for Predicting Flowing Temperature Distribution in Wellbores and Pipelines
Authors: Alves I. N. , Alhanati F. J. S. , Shoham Ovadia 
Published: December 2007

Summary
This paper presents a general and unified equation for flowing temperature prediction that is applicable for the entire range of inclination angles. The equation degenerates into Ramey's equations for ideal gas or incompressible liquid and into the Coulter and Bardon equation, with the appropriate assumptions. This work also proposes an approximate method for calculating the Joule-Thomson coefficient for black-oil models.
Application of Curable Resin-Coated Proppants
Authors: Norman L. R. , Terracina J. M. , McCabe M. A. , Nguyen P. D. 
Published: December 2007

SummaryLaboratory investigation of the interactions between fracturing fluids and resin-coated proppants (RCP's) revealed (among other conclusions) that RCP's are incompatible with oxidizing breakers. Areas covered included RCP effect on fluid rheology, fluid relationship to RCP strength, theoretical study of required RCP strengths to prevent flowback, and experimental measurement to establish minimum strength.