bluuebunny/crossref_metadata_2025_split huggingface dataset:
Contribution of Geomechanics in Evaluation of Heat Transfer Mechanisms at Mobile Zone of SAGD and ES-SAGD
Authors: Shokri A. Rangriz , Hosseini B. Koohmareh 
Published: June 2014

Abstract
Efficient recovery of heavy oil and bitumen in western Canada has widely been applied with thermal-based processes. The well-known Steam-Assisted Gravity Drainage (SAGD) takes advantage of the strong dependency of bitumen viscosity on temperature ranging from 10 to 250 °C. The latent heat of injected steam is released as the steam chamber develops and causes the bitumen to mobilize and drain under the effect of gravity toward the production well. Co-injection of solvent with steam (ES-SAGD) may help to reduce the oleic phase viscosity adjacent to chamber edge by offsetting the temperature reduction effect.
While many researchers are currently tackling the optimal operational conditions from a fluid property point of view (pressure, solvent fraction, etc.), less attention was paid to the impact of heat transfer due to incorporation of geomechanics into occurring physics. Such simplifications in analyzing the real processes physics would result in neglecting of the convection flow of heat along with conduction. Considering the dramatic changes in temperature at the chamber edge, the induced thermal geomechanical responses would lead to a faster fluid movement. The fluid mobility at the edge of chamber would even increase more, mainly because of temperature-dependant heat capacity of water, changes in absolute and relative permeabilities, and possible wettability alteration. If a multi-component solvent is used (ES-SAGD), the assessment of production performance would get more complicated due to the different condensation dynamics of light versus heavy components and the possible gas-blanket effect caused by the co-injected solvent.
In this study, the geomechanical changes due to pressure and temperature effects were considered at the steam chamber, for both SAGD and ES-SAGD scenarios. The thermo-poro-elasticity concept, with elastic constitutive rock behaviour, was chosen for geomechanical study. The primary impacts of geomechanics on the physics of ES-SAGD were rock and fluid alterations, and changes in petrophysical properties (porosity and absolute permeability). Assuming a potential change in rock and fluid interaction due to geomechanics, the same analysis was conducted for a multi-component solvent with different condensation profiles. It was shown how the use of solvent will adversely affect the induced thermal geomechanics contribution. The findings of this paper can be used as a guideline for further experimental studies on the effect of geomechanics in thermal-based recovery processes.
Extending the Role of Compliance: Competent Teams Drive Confident Operations
Authors: Coward Brian Andrew 
Published: June 2014

Abstract
Competence is a word that is used increasingly across process industries and is becoming a core part of legislation in much of the world. Standards and directives such as IEC61508, EU Offshore Safety Directive 2013/30/EU, or indeed the UK Health and Safety Executive's “Managing Competence For Safety-Related Systems” all refer to the requirement to be able to document and assess competence. IEC 61508, Functional Safety of Electrical/Electronic/Programmable Electronic Safety-related Systems (E/E/PE, or E/E/PES) requires that “All persons involved in any overall, E/E/PES or software safety lifecycle activity, including management activities, should have the appropriate training, technical knowledge, experience and qualifications relevant to the specific duties they have to perform.” In addition, it crucially requires that competence be “documented and assessed.”
Competence is developed through many routes – on-the-job training, Original Equipment Manufacturer (OEM) training, formal classroom learning, external classroom courses, through the use of Operator Training Simulators (OTS) or by simply doing a job for many years. What is becoming harder for many companies now though is the ability to map people to competencies, to demonstrably track their staff against these competence requirements and, with the departure of senior people due to retirement, to be able to create the role models for competence profiles so that seamless replacement of staff can happen.
This paper will work through the steps of defining competence, how a competence development and management plan is created and how compliance to the current varying legislation can create more confident operations.
Refinery wastewater degradation with Titanium dioxide, Zinc oxide, and Hydrogen peroxide in a photocatalytic reactor
Authors: Khan Wasi Z. , Najeeb Imad , Tuiyebayeva Madina , Makhteyeva Zhibek 
Published: June 2014

Abstract
This paper presents the photocatalytic degradation of real refinery wastewater from National Refinery Limited (NRL) in Karachi, Pakistan, using TiO2, ZnO, and H2O2. The pretreatment of the refinery effluent was carried out on site and pretreated samples were tested at 32-37 °C in a stirrer bath reactor by using Ultra-Violet photo oxidation process. The degradation of wastewater was measured as a change in initial Chemical Oxygen Demand (COD) and with time. Optimal conditions were obtained for catalyst type, and pH. The titanium dioxide proved to be very effective catalysts in photocatalytic degradation of real refnery wastewater. The maximum degradation achieved was 40.68% by using TiO2 at 37 °C and pH of 4, within 120 minutes of irradiations. When TiO2 was combined with H2O2 the degradation decreased to 25.35%. A higher reaction rate was found for Titanium dioxide. The results indicate that for real refinery wastewater, TiO2 is comparatively more effective than ZnO and H2O2. This study proves that real refinery wastewater reacts differently than synthetic refinery wastewater, oil field produced water or oil water industrial effluent.
Efficient Production Optimization With Flow-Network Models
Authors: Lerlertpakdee Pongsathorn , Jafarpour Behnam , Gildin Eduardo 
Published: June 2014

SummaryAutomating model calibration and production optimization is computationally demanding because of the intensive multiphase-flow-simulation runs that are needed to predict the response of real reservoirs under proposed changes in model inputs. Fast surrogate models have been proposed to speed up reservoir-response predictions without compromising accuracy. Surrogate models either are derived by preserving the physics of the involved processes (e.g., mass balance) to provide reliable long-range predictions or are developed solely on the basis of statistical input/output relations, in which case they can only provide short-range predictions because of the absence of the physical processes that govern the long-term behavior of the reservoir. We present an alternative approach that combines the advantages of both statistics-based and physics-based methods by reducing the flow predictions in complex 3D models to a 1D flow-network model. The existing injection/production wells in the original model form the nodes or vertices of the flow network. Each pair of wells (nodes) in the flow network is connected by use of a 1D numerical simulation model, resulting in a connected network of 1D grid-based simulation models. The coupling between the individual 1D flow models is enforced at the nodes where network edges intersect. The proposed flow-network model provides a useful and fast tool for characterizing interwell connectivity, estimating drainage volume between each pair of wells, and predicting reservoir production over an extended period of time for optimization purposes. The parameters of the flow-network model are estimated by a robust training approach to ensure that the network model reproduces the response of the full model under a wide range of development strategies. This step helps the network model to preserve its predictive power during optimization iterations when alternative development strategies are proposed and evaluated to find the solution. We demonstrate the effectiveness and applicability of the proposed flow-network model by use of two-phase waterflooding experiments.
Experimental Study on the Compressibility of Gelled Crude Oil
Authors: Gang Liu , Lei Chen , Guozhong Zhang , Zhongliang Chen , Yingpeng Hao , Pingsheng Dong , Junfeng Liu 
Published: June 2014

Summary
The compressibility of gelled crude oil is crucial for the restart behavior of a pipeline. However, only a few reports have been published in this field. In this paper, experiments were conducted for the compressibility of waxy crude oil at temperatures lower than pour point. Results show that the compressibility of gelled crude oil is much higher than that of the liquid oil at temperatures above pour point. The compressibility characteristic curve of gelled crude oil is obtained in this research, which shows that the compressibility of gelled crude oil will gradually decrease during the compression process until the gel structure is completely destroyed and the void space is compacted.
Produced Water Management: An Example of a Regulatory Gap
Authors: Khalilpour R.. 
Published: June 2014

AbstractThe current Oil-in-Water (OiW) regulations, measuring only dispersed oil and grease content, have been practiced for long time without any significant improvement. This is whilst the major hazardous portion of produced water falls in dissolved components. Although, in recent years numerous technologies have been commercialized for online measurement and treatment of the entire components of produced water, the regulations have not been updated, except for some limited regions.Given the international awareness of sustainability and the move towards zero discharge, it seems that the environmental authorities have delayed in upgrading their current unsustainable "oil-and-grease" regulations with more accurate ones. It is recommendable to the prospective field developers/operators to take into account the dissolved components of produced water and consider the economic consequences of adopting tertiary produced water polishing technologies.
New Hybrid Drill Bit with Innovative Technology Improves Drilling Efficiency in Challenging Jordanian Drilling Project
Authors: Ismail Ahmed , Moustafa Waleed 
Published: June 2014

Abstract
Major operator is drilling in an exploratory field, located in East Jordan, targeting sandstone reservoir approximately 2,600 m below the surface. Historically, the operator drilled these underbalanced wells with conventional roller-cone and polycrystalline diamond compact (PDC) bits. The drilling project included a 26-in. hole through a tough and highly interbedded formation of mudstone, sandstone and siltstone down to depth of 1,350 m. Inconsistent drilling performance of PDC bits resulted in short run intervals with poor dull conditions. The roller-cone bits also inconsistently drilled the entire interval, achieving slow penetration rates with short runs.
horough in-depth engineering analysis of all available data including rock strength, bit dull, bottomhole assembly, drilling parameters and downhole vibrations, identified the possible root causes for this poor performance and led to a new 26-in. hybrid bit design to overcome the drilling challenges and improve the overall drilling efficiency.
The 26-in. hybrid bit technology with combined elements of PDC bits and tungsten carbide inserts (TCI) was deployed. This combination overcame the drilling challenges in this application and achieved all the operator objectives by drilling the entire 26-in. hole in one run, replacing three bits used to drill the same interval in the offset well, saving five rig days over the planned AFE drilling days.
This paper provides a detailed description of the operational challenges in this application. It then introduces the concept of the new hybrid bit design and provides recommendations based on the performance achieved. After a description of the implementation and operation execution of drilling 26-in. hole in this challenging application, the paper concludes with a discussion of the benefits and value added to the operator by the deployment of this new design approach, highlighting the reduction in number of trips for bit changes.
SP Log Interpretation in Shaly Sands
Authors: Smits L.J.M. 
Published: June 2014

Abstract
A theoretical equation is developed describing membrane potentials of shaly sands as a function of the cation-exchange capacity per unit pore volume of the rock and saturating water salinity. This equation is based on the same simple physical model as that employed earlier describing the electrical conductivity of shaly sands. Experiments conducted with NaCl solutions showed that the equation is obeyed, except in the case of saturated salt solutions where minor deviations were observed. A possible explanation is given for this discrepancy.
As the clay content and the porosity of shales may vary appreciably, shale membrane potentials also vary. It was found that membrane potentials of shales can be calculated accurately with the aid of the same theory. Consequently, changes in membrane potentials can be accounted for by simple measurement of cation-exchange capacities per unit pore volume of both shales and shaly sands. Charts are given to facilitate interpretation of the electrochemical part of the SP in terms of cation-exchange capacities and the salinities of mud filtrate and formation water.

Introduction
A spontaneous potential (SP) log is a record of the way in which the electrical potential of a sonde varies as it passes down a borehole. Such variations frequently reflect rock texture, e.g., permeable beds intercalated in an impermeable series often are indicated by a sharp change in potential. Nowadays it is recognized that SP logs may be interpreted in terms of formation-water salinity and formation shaliness.
The Interpretation of Interference Tests in Naturally Fractured Reservoirs with Uniform Fracture Distribution
Authors: Kazemi H. , Seth M.S. , Thomas G.W. 
Published: June 2014

Abstract
The double-porosity model of Warren and Root for examining pressure drawdown and buildup phenomena in naturally fractured reservoirs has been extended to interpret interference test results. Both analytical and numerical solutions are presented. The practicality of some of the assumptions in the Warren-Root model was also investigated.
The standard procedure for interpreting interference tests in naturally fractured reservoirs heretofore employed an equivalent homogeneous reservoir model. A comparison of our results with the equivalent homogeneous model indicates the latter is inadequate for early time responses. For late time responses, however, the simpler equivalent homogeneous model yields favorable results. Finally, the effects of well spacing and the magnitude of the interporosity flow parameter are briefly cited.

Introduction
Interference tests can be used to provide reservoir information not obtainable from conventional pressure drawdown and buildup tests. The technique involves measuring the response in one or more wells arising from a pressure perturbation introduced into another well. It has been successfully applied to single-layer, homogeneous, unfractured, isotropic and anisotropic formations to arrive at values of well storage capacity and a measure of directional permeability.
Generalization of Wellbore Effects in Pressure Transient Analysis
Authors: Fair W. B. 
Published: June 2014

Abstract
Wellbore effects have been recognized as being important in the analysis of pressure transient tests for many years. Other works have evaluated the effects of wellbore storage and phase redistribution on pressure transient response and analysis methods which account for these effects are well known. It is also known, however, that other wellbore phenomena may affect pressure transient response, but little has been presented which evaluates or generalizes wellbore phenomena in common pressure transient tests.
This paper presents an analysis of generalized wellbore phenomena, including both mass related and momentum affects, shows how these are incorporated into general solutions of the diffusivity equation, and provides general guidelines for recognizing these effects in pressure transient data. In addition, it is shown that the phase redistribution formulation for pressure transient analysis is actually a special case of wellbore mass related phenomena which has much wider applicability than previously realized. Besides general methods for accounting for wellbore phenomena, analytical pressure solutions are also presented for several situations, including heating or cooling of wellbore fluids, phase changes in the wellbore and inertial effects due to rapid acceleration or deceleration of wellbore fluids.
Quantitative Interpretation of Thermal Neutron Decay Time Logs: Part I. Fundamentals and Techniques
Authors: Clavier C. , Hoyle W. , Meunier D. 
Published: June 2014

Introduction
The thermal decay time (TDT) log is based on a measurement of the rate of decay (absorption) of thermal neutrons in a formation. The principle of such logs has been described in detail elsewhere. In Ref. 4 the special features (capture gamma ray detection, Sliding Gate detection system) of the thermal neutron decay time log are described.
Chlorine is by far the strongest neutron absorber of the common earth elements, and the thermal neutron decay time, T, is determined primarily by the sodium chloride present in the formation water. Like the resistivity log, therefore, the thermal neutron decay time measurement is sensitive to the salinity and amount of formation water present in the pore volume. Unlike the resistivity log, this log can be run in cased hole.
Also, the thermal decay time log is relatively unaffected by drilling and completion conditions for the usual borehole and casing sizes encountered over pay zones. Consequently, when formation water salinity permits, this log can detect the presence of hydrocarbons in formations that have been cased, as well as changes in water saturation during the production life of the well. The log is thus useful for evaluating oil wells, for diagnosing production problems, and for following reservoir performance. With a version of the tool that is 1 11/16 in. in diameter, it is possible to enter a producing well through the tubing under pressure without having to kill the well.
Quantitative Interpretation of Thermal Neutron Decay Time Logs: Part II. Interpretation Example, Interpretation Accuracy, and Time-Lapse Technique
Authors: Clavier C. , Hoyle W. , Meunier D. 
Published: June 2014

Introduction
In the second of this two-part treatment of the subject, three main topics will be discussed.The interpretation techniques developed in Part I will be illustrated with an example in a Middle East well. The thermal decay time log was made with a 1 11/16-in. tool lowered through tubing. Neutron and gamma ray logs furnish the necessary porosity and shaliness data. The final results are presented as a computer-produced log.A study is made of the errors that may be tolerated in each of the following items appearing in the equation for water saturation: Slog, Sma, Sh, Sw, Ssh, øe, and Vsh. "Tolerance factors" for each enable the analyst to evaluate the accuracy of actual log interpretation.The time-lapse technique is discussed. In this method two thermal decay time logs are compared, the first one being a reference log run early in the production life of the well. This comparison provides a more accurate evaluation of changes in saturation. The degree of accuracy can be evaluated by means of tolerance factors provided as a result of the error study.

Interpretation Example
Gamma ray, neutron, decay time (run through tubing), and induction-log conductivity curves over an interval of a typical Middle East well are shown on Fig. 1.
Effect of Treatment Parameters on the Geometry of a Hydraulic Fracture
Authors: Daneshy Abbas Ali , Williams James R. , Tinsley John M. 
Published: June 2014

ABSTRACT
The parameters influencing the geometry of a hydraulic fracture are divided into three categories:those upon which there is no control, such as Young's modulus and Poisson's ratio of the formation, far-field stress and the reservoir pressure,those which are easily controlled such as treatment-fluid viscosity and time andthose which are partially changeable, like fluid leak-off and injection rate.
In this paper a study is made of the effects of each individual parameter on the geometry of a hydraulic fracture. Based on the findings reported here, it is concluded that at the present time the treatment-fluid viscosity appears to be the most promising factor for influencing the geometry. Increasing the viscosity has two effects. Directly, it increases the width of the generated fracture, thus yielding better conditions for the transportation of the propping agents. Indirectly, it reduces the volume of fluid lost as leak-off.
Another important conclusion of the paper is that the computed fracture geometries are, to a large degree, influenced by the assumed value of the fracture height. A "reasonable" geometry can be obtained only if one assumes a "reasonable" value for the fracture height.
The Analysis of Single-Well Pulse Tests in a Finite-Acting Slab Reservoir
Authors: Falade Gabriel K. , Brigham William E. 
Published: June 2014

Introduction
Most of the published literature on pulse testing has concentrated on the analysis of pulse tests in infinite domains. Few known comprehensive analyses have been made on tests in finite-acting domains. This is despite the known fact that pulse test results based on the simple infinite model are subject to serious errors if boundary effects are present.
This paper is an illustration of the practical application of the theoretical model presented by Falade and Brigham on "The Dynamics of Vertical Pulse Testing in a Slab Reservoir" with special considerations for the boundary effects.

Review of Model
The transient pressure response due to equal and alternating periods of shut-in and injection (or production) into a test well during vertical pulse testing in a slab reservoir can be described as follows.