bluuebunny/crossref_metadata_2025_split huggingface dataset:
Performance Analysis of Wells With Downhole Water Loop Installation for Water Coning Control
Authors: Jin Lu , Wojtanowicz Andrew K. 
Published: July 2010

Summary
Downhole water sink (DWS) technology controls bottomwater coning by draining water with a second completion placed under the oil-water contact. The technology has been studied theoretically with analytical, numerical and physical models, showing an increased rate of oil production and recovery. Also, improved wells? productivity with DWS has also been demonstrated in several field implementations. However, downhole drainage in DWS wells requires independent lifting of considerable volumes of water that necessitates using either two tubing strings (for water and for oil) or one tubing and the tubing/casing annulus--for water and oil, respectively. Also, extensive water drainage in the systems with weak bottomwater drive may cause a reservoir pressure drop and the need to return the produced water from the surface to the aquifer for pressure maintenance using designated injection wells. DWS well completion with the downhole water loop (DWL) offers the benefit of re-injecting the drainage water back to the same aquifer in the same well without lifting the water to the surface. This could be achieved by designing a DWS well with three completions: the top (oil) completion, the middle completion for water drainage and the bottom completion for water injection. Despite mechanical complexity of the triple well completion, there are two limitations of the DWL system--the drained-and-injected water must be free from oil and the pressure interference between the two water completions must be minimized.
In this work, a well performance (nodal) analysis model has been developed for a DWL well completed in an oil reservoir underlain by water layer of known thickness. In the model, the positions (depths) of the three well completions and the rates of production and drainage/injection are design parameters, while all other properties are reservoir system properties. The model has been used to find the operational range of DWL for a given reservoir system and to compare DWL wells with conventional wells, single-completed at the top of the oil layer.
The results show that for each DWL system, there is such a combination of the top production rate, bottom drainage-injection rate and drainage-injection distance (D/I spacing) that would result in water-free oil production. There is a minimum value of D/I spacing above which the detrimental effect of pressure interference between the two water completions is practically eliminated and the beneficial effect of water drainage on well performance is strong ? a two-fold increase of water drainage rate would increase the critical oil rate by 80%. Also, because the minimum D/I spacing is relatively small, DWL wells may be installed in reservoirs with thin layers of bottomwater.
Conducting SAGD in Shoreface Oil Sands With Associated Basal Water
Authors: Peterson Jeff , Riva D.T. , Connelly M.E. , Solanki S.C. , Edmunds Neil R. 
Published: July 2010

Summary
The majority of steam assisted gravity drainage (SAGD) development to date has been concentrated in the McMurray formation in the Eastern Athabasca fairway. More recently operators have identified projects with considerable resources located in shoreface sands of the Grand Rapids formation in the Wabasca area. Laricina Energy's Germain thermal project in Grand Rapids has associated basal water underlying much of the reservoir. In this paper the authors show that SAGD can be configured to maximize bitumen recovery for such reservoirs, based on laboratory and new simulation studies. The result is a SAGD configuration where the producers are placed at the base of porosity, within the basal water zone.
New Method of Well Test Analysis in Naturally Fractured Reservoirs Based on Elliptical Flow
Authors: Igbokoyi Alpheus , Tiab Djebbar 
Published: July 2010

Summary
Up-to-date well test analysis in naturally fractured reservoirs is based on the radial flow model. The radial flow model is only applicable to purely homogeneous systems and is a long-term solution in general. It cannot provide complete formation analysis in reservoirs that exhibit anisotropy. This study, therefore, presents a new method of estimating permeability anisotropy in naturally fractured reservoirs.
Maximum and minimum permeability are obtained from a single well test. The maximum permeability is attributed to the large-scale fractures in the system, while the minimum permeability may be caused by the small-scale fractures orthogonal to the large-scale fractures. In a situation where the fractures are oriented in one direction, the minimum permeability will reflect the matrix permeability. The type of flow path developed (narrow or wide flow path) can also be predicted. This is useful in predicting the direction of fluid-flow.
Application was made to four field examples, among which was an interference test. The interference test was used as a validation process. The results obtained are in agreement with that of the interference test method of analysis.
Model Uncertainties and Resolution Studies With Application to Subsurface Movement of a CO2 Injection Project in the Krechba Field Using InSAR Data
Authors: Du Jing , McColpin Glenn R. , Davis Eric J. , Marsic Scott 
Published: July 2010

Summary
Surface deformation-based reservoir monitoring technologies, such as Tilt, GPS and Interferometric Synthetic Aperture Radar (InSAR), have been successfully applied to monitor fluid flow or pressure changes in the reservoir and fluid migration to shallow depths. Obtaining the subsurface fluid movement from the surface deformation requires performing a geophysical inversion. To get meaningful results from the inversion process requires diligent selection of the inversion method and reservoir block sizes, as well as the application of physically reasonable constraints. The focus of this paper is to provide a workflow and guidelines for field application by studying the inverse problem, the solution methods and associated error estimates for the unknown model parameters, and the resolving power for each parameter. As a field case demonstration, the methodologies are applied to a CO2 monitoring project with InSAR data. Also, the subsurface movement of CO2 will be presented.
Evidence That Naturally Occurring Inhibitors Affect the Low-Temperature Oxidation Kinetics of Heavy Oil
Authors: Freitag Norman P. 
Published: July 2010

Summary
The so-called induction period, the time delay between the initial exposure to oxygen of an oil or oil fraction and the start of rapid oxidation, was examined experimentally for the saturates fraction separated from a Lloydminster heavy oil. The observed kinetics could be explained by assuming that the saturates contained a small amount of naturally occurring oxidation inhibitors, which repressed the oxidation rates by rapidly consuming an essential intermediate in the reaction chain, but which were also gradually consumed in the process. This observation explains some of the complexity that has been seen in the oxidation rates that control combustion front development during in-situ combustion, and provides some added direction in the development of a comprehensive reaction model for this process.
Investigation of the Complex Flow Behaviour of Surfactant-Based Fluids in Straight Tubing
Authors: Kamel Ahmed H. Ahmed , Shah Subhash 
Published: July 2010

Summary
In spite of their wide use in hydraulic fracturing and gravel-pack operations, the complex flow behaviour of surfactant-based (SB) fluids in straight tubing is rarely investigated. Accurate prediction of friction-pressure is essential for proper treatment design. Previous correlations from small tubing data and using simple power-law fluid model parameters alone do not scaleup to large tubing sizes for field application.
The properties of one of the most popular surfactants, Aromox APA-T, are thoroughly investigated. It is a highly-active surfactant used as the gelling agent in aqueous and brine solutions. Commonly used surfactant concentrations (1.5%, 2%, 3% and 4% by volume) are studied. Rheological and viscoelastic measurements are conducted using the Bohlin rheometer. Flow tests are conducted using 1.27-cm, 3.81-cm, 6.03-cm and 7.30-cm tubing.
The results show SB fluid exhibiting a non-Newtonian pseudo-plastic behaviour. Fluid concentration and pipe shear have a significant effect on fluid elasticity. The conventional Fanning friction factor vs. Reynolds number correlation is improved by including a new dimensionless group that accounts for both fluid elasticity and pipe diameter. A new definition of Deborah number is introduced. Thus, a new correlation for predicting friction factors of SB fluid in straight tubing is developed. The scaleup problem is thus alleviated with the present analysis and this provides more accurate friction-pressure estimates.
The Design and Development of a Drilling Simulator for Planning and Optimizing Under-Balanced Drilling Operations
Authors: Shirkavand Farid , Hareland Geir , Olson Wayne 
Published: July 2010

Summary
Computer simulation technology has been widely applied in many drilling engineering areas to simulate drilling engineering problems and optimization, to train engineers with real drilling operations and/or to handle rare applications and accidents.
Among the increasingly applied drilling operations is under-balanced drilling (UBD). UBD is the drilling process in which the wellbore pressure is intentionally designed to be lower than the pressure of the formation being drilled. This results in a higher rate of penetration (ROP) and prevents fluid losses and related causes of formation damage.
This paper presents the design and development of a UBD simulator, which is computer software that simulates and integrates the effects of:
Bottomhole pressure (BHP).
Minimum volumetric gas and liquid requirement.
Required backpressure (BP) for required cutting removal to surface and controlling BHP.
Kinematic energy per unit volume used in the hole cleaning considerations.
Stand pipe pressure (SPP).
Rock drillability.
ROP.
Drilling costs per metre.
The goal of the simulator is to enable the user to pre-simulate different scenarios of the UBD drilling operations; therefore, the ideal optimized combination of drill bit durability and drilling efficiency, integrating all UBD operational parameters affecting the overall cost, can be obtained before the fact. The UBD simulator is designed to simulate most of the basic technologies of UBD (air, aerated and foam drilling). The goal of the UBD simulator is to design an effective UBD program by linking the BHP to rock drillability, which takes into account the effect and degree of under-balance on the effective rock strength, ROP and $/m that can be optimized for the operation. The complete UBD optimization integration is shown herein with illustrations including flowcharts.
Discussion of Permeability Anisotropy Effect in Transformation
Authors: Sheng James 
Published: July 2010

Summary
To solve an anisotropic flow problem, the problem is transformed into an equivalent isotropic problem. It is expected that an anisotropic solution can be readily obtained from the equivalent isotropic solution. However, sometimes that is not the case. Using the drawdown equation of a fully penetrated vertical well test and the drawdown and buildup equations for a probe test, this paper discusses when it is both possible and impossible to directly obtain an anisotropic solution from an isotropic solution. Because of the fact that transformation causes the changes in flow geometry and the shape of the wellbore or probe, the equivalent isotropic solution must be modified to obtain the anisotropic solution. Finally, a case of how horizontal well productivity was incorrectly derived in a published paper --caused by the misuse of the concept of anisotropy--is presented.
The full manuscript of SPE 114504, Discussion of Permeability Anisotropy Effect, is available as a supplement to this article.
Importance of Reservoir Description In Evaluating In-Situ Recovery Methods For Cold Lake Heavy Oil Part 2 - In-Situ Application
Authors: Towson D.E. 
Published: July 2010

Abstract
The huge reserves of heavy oil in Alberta are found in a variety of complexreservoirs. Recovery, excluding mining, will require application of some formof in-situ recovery methods, primarily in the better reservoirs. The properselection of an in-situ method, applicable to the various reservoir types, requires a basic understanding of reservoir description and the engineeringaspect of the reservoirs. In Part 1 of this paper, reservoir description in the Cold Lake heavy oil deposits was discussed under three headings:rockproperties;fluid saturation; andreservoir geometry.
Based on theseparameters, five selected reservoir types are discussed and compared.
Part 2 considers the application of the reservoir description in evaluatingin-situ methods. The significance of the reservoir parameters is discussed ingeneral terms and related to the four most important in-situ recoverymechanisms: steam stimulation, steam drive, combustion and solvent. Thereservoir description is then used as the basis of comparison of the recoverymechanisms for each of the live Cold Lake reservoir types described in Part1.

Introduction
The oil sands deposits in Alberta, according to recent estimates, containmore than 900 billion barrels of oil in place. However, with the currenttechnology, only a small percentage of the sands can be surface minedeconomically. The remainder will require some form of in-situ recovery process.The paper deals with the importance of reservoir description in evaluating thevarious in-situ methods for application in these tar sand deposits.
Part 1 of the paper discussed the reservoir description for the Cold Lakedeposit in terms of rock properties, fluid saturation and reservoir geometry.Based on these parameters, five selected reservoir types were identified andcompared.
Part 2 considers the application of reservoir description in evaluatingin-situ recovery methods with specific reference to the Cold Lake deposit.
Test of Steam-foam Process for Mobility Control in South Casper Creek Reservoir
Authors: Mohammadi S.S. , Coombe D.A. , Stevenson V.M. 
Published: July 2010

Abstract
The South Casper Creek field in Wyoming produces a viscous fourteen gravitycrude from an eolian Tensleep sandstone at 790 m. The field has been underthermal development since the mid 1970' s with cyclic activities. In mid tolate 1980' s, a number of patterns were converted to steamdrive. Typicalresponse, however, showed clear indication of rapid steam breakthrough.Simulation of the steamflood response along with detailed geologic studiesshowed the existence of a high permeability channel. These results were furtherconfirmed by a tracer study using tritiated water.
In an attempt to evaluate the effectiveness of foam for correcting prematuresteam channeling, a mini-foam pilot test was conducted. Using a compositionalthermal simulator, code named STARS, the results of this mini test were historymatched and used for prediction of reservoir response to a six-month long foaminjection project.
The mini-foam test involved continuous addition of low concentration of aformulated alkyl aryl sulfonate, and natural gas, to the injected steam. Duringa ten-day period. 4500kg of active chemical were injected. The testincluding injection, pre-and post monitoring lasted one year. Injectionwellhead pressure, as well as produced fluid temperatures and compositions wereused for monitoring of the project. Composition monitoring involved thedetermination of the concentration of dissolved solids in produced water frompilot and peripheral producers. The results of this test showed that foam hadresulted in steam diversion away from a hot peripheral producer. This wasdecided based on a gradual reduction of produced fluid temperature, from 150°Cto 105°C(from 305°Fto 220°F), and a corresponding increase inconcentration of Total Dissolved Solids, from 1900 PPM to 2500PPM.
The project proved both the effectiveness of the formulated alkylarylsulfonate in redistributing steam and the ability of the simulator to accountfor the observed behavior. Simulation results further showed that cumulativeoil recovery had increased by 5.6%as a result of six months of foaminjection in this pilot.
A Practical Method for Theoretically Determining the Productivity of Multi-fractured Horizontal Wells
Authors: Kuppe F. , Settari A. 
Published: July 2010

Abstract
This work investigates the productivity of different configurations offractured horizontal wells by means of numerical simulation. Model results havebeen compared to a number of analytical solutions available for estimating theproductivity of unfractured horizontal wells under various boundary conditions.The simulation model was expanded to include varying lengths of one, three, five, and seven infinite conductivity, vertical hydraulic fractureconfigurations. In this work, infinite (high) fracture conductivity was used, although the model can also be used to investigate the effect of finiteconductivity. Based on the numerical results, a third order polynomialcorrection to the linear flow equation was developed to yield more accurateproductivity index predictions without the limitations of analyticalsolutions.
The empirical formula, generated from this work, can be used easily foraccurate predictions of multi-fractured horizontal well productivity andproject economics, under a variety of reservoir and boundary conditions.

Introduction
The productivity and hydrocarbon recovery benefits of horizontal wells, compared to their vertical counterparts are, by now, well established concepts.The unstimulated horizontal well can generate production rates of two to fivetimes that of an unstimulated vertical well at similar pressure drawdowns(1).In addition, horizontal wells that intersect natural fractures dramaticallyincrease reservoir contact area and, consequently, further increase theproductivity and drainage efficiency(1,2). Historically, horizontal wells havebeen less effective in thicker reservoirs (with thicknesses in the order of 500ft. or more), reservoirs with low vertical permeability (relative to horizontalpermeability), and in stratified reservoirs with impermeable shale barriers.The improvement of well completion and stimulation technology, however, isrenewing enthusiasm for horizontal well applications in areas that werepreviously considered unqualified.
The use of hydraulic fractures to enhance horizontal well productivity wasforeseen already in early works by Giger et al(1) and Giger(2).
With the advent of fractured horizontal wells (or unstimulated horizontalwells, for that matter) has come a host of analytical solutions, developed topredict the productivity of these wells, although too few includefractures.
Large Scale Carbon Dioxide Production from Coal-fired Power Stations for Enhanced Oil Recovery: A New Economic Feasibility Study
Authors: Tontiwachwuthikul P. , Chan C.W. , Kritpiphat W. , Demontigny D. , Skoropad D. , Gelowitz D. , Aroonwilas A. , Mourits F. , Wilson M. , Ward L. 
Published: July 2010

Abstract
Enhanced oil recovery (EOR) technologies must be increasingly applied inorder to sustain the current production capacity of conventional oil in Western Canada. Among these technologies, carbon dioxide (CO2) flooding isa highly attractive possibility. At the same time, a large amount of CO2 is being produced by coal-fired power plants in this region. The CO2 is currently discharged into the atmosphere and could be a majorcontributor to the so-called greenhouse effect, which would lead to globalwarming. Thus, the concept of capturing CO2 and utilizing it as aflooding agent in EOR processes is currently generating much interest amongoil, utility and coal companies. This paper describes how cogenerationconcepts, together with process optimization strategies, help to reduce the CO2 production cost by utilizing low-pressure steam and waste heatfrom various sections of the power generation process. Based on these conceptsand strategies, results from this study show that the recovery cost of CO2 from a coal-fired power plant can range between $0.50 –2.00/mscf. If the cost is approximately $1.25/mscf, the production cost of abarrel of incremental oil would be less than $18. Therefore, at modest oilprices, there is room for profit to be made operating a CO2 floodwith flue gas extracted CO2, The technical and economic feasibilityof the concepts are evaluated and practical implications for the Saskatchewanresources are discussed.

Introduction
Oil, utility and coal companies in Western Canada are increasinglyinterested in the concept of capturing CO2 from coal-fired powerstations and utilizing it as a flooding agent for EOR processes. Implementationof such a scheme would provide two important benefits:the captured CO2 could be marketed as a flooding agent which would generaterevenues, andCO2 emissions to the atmosphere would be reduced.Since CO2 emissions are considered to be the main contributor to thepossible serious environmental problem of global warming, the proposed schemecould become an important instrument to reduce such emissions at minimalincremental cost.
In Utero Exposure to Maternal Diabetes Impairs Vascular Expression of Prostacyclin Receptor in Rat Offspring
Authors: Van Huyen Jean-Paul Duong , Vessières Emilie , Perret Claudine , Troise Adrien , Prince Sonia , Guihot Anne-Laure , Barbry Pascal , Henrion Daniel , Bruneval Patrick , Laurent Stéphane , Lelièvre-Pégorier Martine , Fassot Céline 
Published: July 2010

OBJECTIVE
To evaluate modifications of arterial structure, gene expression, and function in our model of rats exposed to maternal diabetes.

RESEARCH DESIGN AND METHODS
Morphometric analyses of elastic vessels structure and determination of thoracic aortic gene expression profile with oligonucleotide chips (Agilent, G4130, 22k) were performed before the onset of established hypertension (3 months).

RESULTS
Arterial parameters of in situ fixed thoracic aorta were not significantly different between control mother offspring and diabetic mother offspring (DMO). The aortic gene expression profile of DMO is characterized by modifications of several members of the arachidonic acid metabolism including a twofold underexpression of prostacyclin receptor, which could contribute to decreased vasodilatation. This was confirmed by ex vivo experiments on isolated aortic rings. Pharmacological studies on conscious rats showed that systolic blood pressure decline in response to a PGI2 analog was impaired in DMO rats.

CONCLUSIONS
These results suggest an abnormal vascular fetal programming of prostacyclin receptor in rats exposed in utero to maternal hyperglycemia that is associated with impaired vasodilatation and may be involved in the pathophysiology of hypertension in this model.