bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Inflow Performance Relationship for Horizontal Gas Wells
Authors: Akhimiona N. , Wiggins M. L. 
Published: December 2007

Abstract
As an increasing number of horizontal gas wells are drilled, the need for a quick and reliable method to estimate the pressure-rate behavior of these wells is important to optimize well performance and make operational decisions. A reliable empirical relationship will provide engineers a technique to assess the performance of horizontal gas wells prior to undertaking extensive and often time-consuming simulation studies to model the well behavior.
This work presents an analysis of the pressure-rate performance of horizontal gas wells using a three-dimensional finite difference reservoir simulator for different reservoir and wellbore conditions. The primary objective of this work is to study the pressure-rate behavior of horizontal gas wells and develop an empirical inflow performance relationship to predict their behavior.
The study investigates a range of reservoir conditions to assess their effect on horizontal gas well behavior. Parameters studied include reservoir permeability, permeability anisotropy, gas gravity, drainage area, pay thickness and horizontal wellbore length. The obtained data is used to develop empirical inflow performance relationships (IPRs) to predict the pressure-rate behavior of gas wells. The IPRs are presented in terms of pressure, pressure-squared, and pseudopressure. The resulting IPRs provide a tool by which the petroleum engineer can quickly estimate the performance of a horizontal gas well without undertaking a time-consuming simulation study.
Integrated Reservoir Management For Life Extension of a Mature and Marginal Oilfield–Talara Basin, Peru
Authors: Yesquen S. , Carro J. L. , López L. 
Published: December 2007

Abstract
Oil production in Peru is based on the development of mature fields with highly complex geological and reservoir characteristics; therefore, a great amount of creativity is required to operate these old fields. This is particularly true of fields located along the north coast where the low productivity of reservoirs reduce the attractiveness of development projects.
This paper outlines the Integrated Reservoir Management Process that Petrobras started in 1996 in Block X, located in the northwest of Peru on the Talara Basin – the oldest producing basin in South America with more than 100 years of continuous production.
The results obtained through the reservoirs revitalization and rejuvenation clearly reflects on the production decline variation and are based on the following aspects: Better knowledge and description of reservoirs.Optimization of development and operational costsStrong commitment to guarantee safety and environment preservation.Reasonable use and adaptation of technological advances.Human resources management program.Establishment of smaller royalties for the government to ensure new investments.
Controlling Formation Fines at their Sources to Maintain Well Productivity
Authors: Nguyen P. D. , Weaver J. D. , Rickman R. D. , Dusterhoft R. G. , Parker M. A. 
Published: December 2007

AbstractMigration of formation fines has been shown to cause production decline in many wells. Despite the availability of new downhole tools for use in well stimulation and completion, the ability to sustain desired production levels is often plagued with fines migration problems. This dilemma requires appropriate treatment to mitigate fines migration at its source. This paper describes the use of an ultra-thin tackifying agent (UTTA) for stabilizing fines in high rate producing or injecting wells. This UTTA is applied as part of an initial prepad in fracturing or gravel-packing operations, a remedial treatment, or as a post-treatment following acid fracturing or matrix acidizing treatments. The primary purpose of UTTA application is to immobilize formation fines so that they will not detach, migrate with flowing fluids, plug the pore channels, and reduce the flow path permeability.Results of laboratory testing indicate that the UTTA system is applicable to most types of formation fines, including coals, sandstones, and carbonates. Once injected into the formation matrix or proppant pack, the UTTA forms a thin film on formation surfaces, encapsulating the fines. Capillary action helps pull the tackifier into the contact points, fixing the particulate in place without plugging the pore throat. The UTTA does not require a shut-in time after its application. The thin film tackifier does not harden, but remains flexible, enhancing the ability of a formation to withstand stress cycling and allowing the formation to handle high shear stress during high flow rates.
Application of Improved and Enhanced Oil Recovery Strategies in the Tapis Field
Authors: Wan-Mohamad W-N. , Abdullah M. A. Y. , Selamat S. , Elias M. R. 
Published: December 2007

Abstract
The Tapis field, located offshore peninsula Malaysia, has been producing since 1978 and about 90% of the original development estimated recoverable oil has been produced. Large gas caps remain for future development. Recovery to date has been primarily from line drive pattern waterflood. Continuous implementation of improved oil recovery (IOR) strategies has increased the recoverable reserves and production capacity for economic operation of the field. This paper describes technical studies completed at Tapis and the results of recent IOR work programs that added more than 20 million barrels of reserves. In addition, enhanced oil recovery techniques currently under evaluation for Tapis are described.
The Tapis structure is an east-west trending anticline, approximately 16 km long and 7 km wide. Initially, only the northern and eastern areas were developed from four platforms. The other areas were only developed in recent years following studies to re-assess recovery from poorer quality reservoirs and application of more cost-effective technologies to commercialize them. This led to a fifth platform that developed the western area of the field.
Recently, the southern flank with marginal reserves was developed from a sixth platform, which adopted the minimal facilities satellite platform concept. Reservoir risk for this development was mitigated by additional exploration/ delineation and development well data. The data confirmed that the reservoirs are oil-bearing and productive. This marginal development was a challenge due to reservoir quality uncertainties (extensive bioturbation), structural complexities (steep bed dips, close to a major reverse fault), and fluid contact uncertainties caused by production. Reservoir simulation study was carried out to address these uncertainties to aid development planning.
Reservoir simulation study has also identified the potential for infill drilling and workovers to further improve recovery in the eastern area. This latest simulation study was conducted using finer layers, unstructured grids, and incorporated over 25 years of history matching.
Given the advanced state of field depletion, early assessment utilizing compositional simulation model and laboratory tests are being carried out to investigate the potential for enhanced oil recovery processes. Processes under evaluation include double displacement and water alternating gas (WAG) displacement using various types of gas.
Steam-Injection Strategy and Energetics of Steam-Assisted Gravity Drainage
Authors: Gates I. D. , Kenny J. , Hernandez-Hdez I. L. , Bunio G. L. 
Published: December 2007

Abstract
Steam-Assisted Gravity Drainage (SAGD) is being operated by several operators in Athabasca and Cold Lake reservoirs in Central and Northern Alberta. In this process, steam, injected into a horizontal well, flows outwards, contacts and loses its latent heat to bitumen at the edge of a depletion chamber. As a consequence, the viscosity of the bitumen falls, its mobility rises, and it flows under the action of gravity towards a horizontal production well located several meters below and parallel to the injection well. In practice, the temperature difference between the injected steam and produced fluids, called the subcool, is maintained between 15 and 30°C. Despite many pilots and commercial operations, it remains unclear what the impact of subcool on the performance and thermal efficiency of SAGD especially in reservoirs with a top gas zone. The objective of this study was to define a steam chamber operating strategy that leads to optimum oil recovery for minimum cumulative steam to oil ratio in a reservoir with a top gas zone. These findings were established from extensive simulation runs that were built from a detailed geostatistically generated static reservoir model. The strategy devised uses a high initial chamber injection rate and pressure prior to chamber contact with the top gas. Subsequent to breakthrough of the chamber into the gas cap zone, the chamber injection rates are lowered to balance pressures with the top gas and avoid or at least minimize convective heat losses of steam to the top gas zone. The results are also analyzed by examining the energetics of SAGD.
Pipeline Lubrication of Heavy Oil: Experimental Investigation of Flow and Restart Problems
Authors: Peysson Y. , Bensakhria A. , Antonini G. , Argillier J. F. 
Published: December 2007

Abstract
Heavy oil represents a large quantity of hydrocarbon resources. Unfortunately its high viscosity makes it difficult to produce and to transport. Different solutions have been developed to transport heavy oil in pipeline like blending the crude oil by a light hydrocarbon. In this study we investigate a technique based on two-phase flow: pipeline lubrication. A thin water film is injected around the internal oil core and lead to the core-annular flow regime. Water lubricates the heavy oil and longitudinal pressure gradient is then largely reduced. An experimental study has been carried out where the influence of the water content and oil flow rate has been optimized for real heavy oil as the core of the flow. The tests were conducted in steady laminar flow at moderate flow rates. The results, obtained with annular water injection at the pipe wall, show a pressure drop reduction over than 90% as compared with the same product without lubrication. These results confirm the effectiveness of the lubricating process for heavy oil transport. Restart problems and specifically the limitation of restart pressure has been also investigated.
Post-Yield Thermal Design Basis for Slotted Liner
Authors: Dall'Acqua D. , Smith D. T. , Kaiser T. M. V. 
Published: December 2007

Abstract
Slotted liners used for primary heavy oil recovery support relatively minor operational loads at the depths and pressures common in Western Canada. In such applications, installation loading is the primary concern, and load limits can be defined using an elastic design basis to support running operations. In thermal operations, the installation limits need to be more stringent, because of the impact of residual stresses and deformation on the operating response. Furthermore, the high axial loads induced by confined thermal expansion can place the liner into large-scale yield, where localization resistance is virtually eliminated and a variety of deformation failure mechanisms can become manifest. A prudent design takes the deformation mechanisms into consideration, balancing the mechanical requirements for supporting thermally-induced loads against the inflow requirements to generate the final design.
Commercial Steam Assisted Gravity Drainage (SAGD) projects currently under development in Northern Alberta typically use slotted liner for both injectors and producers. Reservoir sand grain size distributions and inflow requirements require slot densities as high as possible without compromising the structural integrity of the wells. Therefore, a design assessment was required to determine the relationship between slot geometry and density, thermal and production loading, and post-yield material properties. A variety of possible failure mechanisms were considered, and failure limits in terms of these controlling parameters were evaluated. The outcome was an allowable slot density, slot geometry and post-yield material description required for the liner to operate reliably, and corresponding quality assurance programs to ensure the slots and material satisfy the requirements for reliable operation.
Leveraging a New Energy Source To Enhance Heavy-Oil and Oil-Sands Production
Authors: Geddes C. J. , Curlett H. B. 
Published: December 2007

Abstract
Every day, approximately 800 million cubic feet of gas is burned in the oil sands region of Alberta in the extraction and processing of heavy oil and bitumen (see Figure 1).1 The vast majority of this energy is used in the creation of steam for Cyclic and SAGD oil production processes for bitumen extraction from the oil sands. One of the main factors limiting further expansion of the oil sands and heavy oil development in the region is natural gas usage.
A dependable and predictable energy source is required for continued development of heavy oil and oil sands production in Alberta. Natural gas is currently the preferred source; however, the future availability of a natural gas supply for the region and the cost of that supply are unknown variables with significant economic ramifications. Economic justification of new projects under such conditions is, at best, challenging.
Alberta, and clearly the world, is sitting on a virtually unlimited supply of usable geothermal heat energy that would be an attractive solution to the oil sands energy source problem. The green aspects of geothermal energy are appealing for both ethical and political reasons. Of even greater importance to the bitumen producer is that geothermal energy has the potential to provide a significantly positive impact to project economics – the future availability of an energy source that is guaranteed and at a known cost.
Emulsion Stability Evaluation of SAGD Product with the IPR-CEF Technique
Authors: Beetge J. H. 
Published: December 2007

Abstract
The IPR-CEF technique has recently been developed as a quantitative method for emulsion stability evaluation of water-in-oil emulsions. Critical electric field (CEF) measurements, made with variation in the internal phase ratio (IPR) of oil external emulsions, can reveal more information related to the mechanism of emulsion stabilization, specifically in terms of its flocculation and coalescence behavior.
Emulsions made with bitumen from a Steam Assisted Gravity Drainage (SAGD) facility were investigated by application of the IPR-CEF technique in an explorative study to evaluate the performance of the technique. The stabilization mechanism of these emulsions was also studied to explore the effect of bitumen concentration and diluent character on emulsion stability, in terms of flocculation and coalescence behavior. An attempt was made to investigate the mechanism of destabilization by a chemical demulsifier.
It is shown that the IPR-CEF technique offers valuable insight, both in understanding the mechanism of stabilization of SAGD based emulsions as well as the mechanism of demulsification by a chemical demulsifier.
Transient-Pressure Behavior of Cold Heavy-Oil Production Wells
Authors: Liu X. , Zhao G. 
Published: December 2007

Abstract
The objective of this paper is to investigate the transient pressure behavior of Cold Heavy Oil Production (CHOP) wells with the consideration of wormhole configurations and foamy oil flow. Wormholes provide main conduits for foamy oil flow in the production process, and foamy oil is highly compressible owing to the dispersed and encompassed gas bubbles. This study proposes a comprehensive model to describe the transient flow of matured CHOP wells. Then, the transient pressure behavior has been extensively analyzed. The model not only provides reliable transient pressure responses of matured CHOP wells, but also offers a way to estimate the possible wormhole configurations and to understand the possible pressure drop along wormholes.
Development Status of a Metal Progressing Cavity Pump for Heavy Oil and Hot Production Wells
Authors: Beauquin J. -L. , Boireau C. , Lemay L. , Seince L. 
Published: December 2007

Abstract
Cold Heavy Oil Production is mainly achieved by Progressing Cavity Pumps (PCP) nowadays, thanks to its low CAPEX and OPEX and adaptability to viscous and abrasive fluids. However, for thermal recovery, standard PCP is not adapted, as the elastomer composing the stator, the heart of the pump, can't withstand fluid temperature above 160°C (320F) so far. Innovative research led to the development of an original manufacturing process of a complete metallic pump, avoiding the elastomer weakness. The use of metallic PCP is in an advanced test phase. PCM and TOTAL launched industrial validation tests early 2005 in TOTAL test bench using extra heavy crude with temperatures up to 200°C (390F), pressure up to 75 bars (1090psi) and flowrate up to 260 m3/day (1600bpd) at 350 rpm. The flowrate range will be as high as 1000 m3/day (6300bpd) with new models available later this year. The validation program includes long-time running performance tests to validate its behaviour on abrasion & gas handling. Field tests will be performed before the end of the year. This paper presents the technology and promised performances associated with metal PCP used for heavy oil cold or thermal production.
Diffusivity in Heavy Oils
Authors: Creux P. , Meyer V. , Graciaa A. , Cordelier P. R. , Franco F. , Montel F. 
Published: December 2007

Abstract
Molecular diffusion of gases in heavy oils is one of the most important physical parameter governing cold production processes such as solution gas drive or Vapex. Indeed, the way bubbles are able to grow by diffusion will have a direct impact on gas mobilization and consequently on oil recovery. Furthermore, the importance of this parameter is emphasized by the very low gas availability characterizing extra heavy oils.
Surprisingly, publications of experimental data concerning gas diffusivity in heavy oils are relatively rare. Furthermore, published values can vary by different orders of magnitude. This is probably due to the fact that this kind of measurement is quite tricky. Indeed gas leakages in high pressure cells could be in the same order of magnitude than gas diffusion in oil. To study very viscous oil (extra heavy oils), corresponding to very low diffusivity, it is thus necessary to carefully analyze the obtained results.
The aim of this work is to characterize experimental fickian diffusivity of methane in heavy oils using two different concepts in order to be able to validate the experimental results. In this paper we present the two different methods (thermophysics and analytical) we have settled. Experimental results clearly indicate that diffusivity in extra heavy oils is lower than usually considered for ‘conventional’ oil.
From various experimental results we also propose a first mathematical model to simulate the influence of temperature on gas diffusivity.
H2S Artificial Formation as a Result of Steam Injection for EOR: A Compositional Kinetic Approach
Authors: Lamoureux-Var V. , Lorant F. 
Published: December 2007

Abstract
As a result of hydrothermal stress induced by steam injection in reservoirs, heavy crudes undergo chemical transformations, called aquathermolysis, the extent of which depends at least on steam temperature, injection history and both crude and mineral matrix physicochemical properties. As heavy crudes often have high sulfur content, their hydrothermal alteration results in the formation of H2S. In order to predict artificial H2S emissions during thermal EOR, we seek to develop a geochemical model to be coupled with a 3D reservoir simulator.
This paper presents the first step of the process that consists in simulating in-situ aquathermoysis in laboratory in order to derive a 0D compositional kinetic model for H2S formation.
For that purpose, aquathermolysis experiments were performed on an Athabasca oil sand sample. The amount of H2S generated during aquathermolysis was measured for different time and temperature conditions. At the same time, sulfur distribution was quantified over crude SARA fractions (Saturates, Aromatics, Resins and Asphaltenes) and insoluble fraction (mainly mineral), before and after aquathermolysis. Experimental results were then derived to elaborate a kinetic model of H2S generation upon aquathermolysis, encompassing the chemical conversion of sulfur in SARA and insoluble fractions.
Laboratory Development and Application of a Synthetic Oil/Surfactant System for Cleanup of OB and SBM Filter Cakes
Authors: Berry S. L. , Beall B. B. 
Published: December 2007

Abstract
During the drilling process with OB (oil-based) and SB (synthetic-based) mud systems, mud solids form internal and external filter cake along the wellbore through a filtration process (due to filtrate leakoff to the formation). After drilling is complete, a cleanup treatment to remove the OB/SB mud filter cake is needed to minimize skin and formation damage and increase production flow area. The cleanup treatment is necessary to break down the external water-in-oil emulsion filter cake, wash the damaged zone of the wellbore, and restore the formation fluid transfer properties.
Historically, solvent- or aqueous-based systems have been widely used to remove OB and SBM filter cakes. Solvent treatments are typically very expensive and aqueous systems may cause additional formation damage by forming emulsions and/or creating water saturation in the wellbore, thereby blocking oil production.
A successful OB/SBM filter cake treatment must break the mud's interfacial rheological properties, act as a demulsifier to break the water-in-oil emulsion, and break the filter cake's bond with the wellbore wall.
A synthetic oil/surfactant-based fluid system has been developed to cleanup OB and SB mud filter cakes. This paper discusses laboratory evaluation studies of the treatment fluid's effectiveness in breaking the emulsion inside the filter cake across a wide range of mud types to reduce cake cohesion and wellbore adherence. Studies with 10 field mud compositions from several mud suppliers have been conducted to evaluate the treatment fluid's filter cake removal efficiency. Laboratory data is presented showing the physical properties of each drilling mud's filter cake before and after treatment as well as the treatment's filter cake removal efficiency. Photos of the initial and post-treatment mud filter cakes are also provided for review. Finally, the paper will discuss the possible advantages of using a synthetic oil-based cleanup system over traditional aqueous-based treatments.