bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Specially Designed Organophilic Chloride-Free Reservoir Drill-In Fluid Meets the Challenges of the First Horizontal Well in Mozambique
Authors: Ezeigbo E. , Luyster M. , Ravitz R. , Pereira A. , Nguyen C. 
Published: June 2014

Abstract
An operator was planning to drill the first horizontal well in the Inhassoro field in Mozambique. The type of completion would be an open hole utilizing expandable screen technology. The formation had highly reactive shale stringers necessitating the use of an inhibitive fluid, but due to the environmental restrictions, the use of non-aqueous fluid systems could not be used to drill or complete the horizontal section. The issue of cleaning up the filter cake was examined as it would be confined with the use of the expandable screen. Normally a breaker system would be required to cleanup or disperse the filter cake with this type of completion; but due to the water sensitivity of the reservoir, any aqueous filtercake breaker would have to be left out of the completion process.
The reservoir drill-in system used to drill horizontal section would require an inhibitive water-based fluid that was also chloride free due to possible contact with the ground water. The system would also require a filter cake that could be cleaned up with the producing hydrocarbons due to the absence of any filtercake breaker system. The filter cake must also demonstrate a low permeability in order to limit the invasion of fluid into the sensitive formation. A low coefficient of friction would also be another requirement for the reservoir drill-in system.
This paper will highlight the design optimization, the unique characteristic, the testing and the successful implementation of this special reservoir drill-in system.
Vitality of Formation Damage Causing Microorganisms in Brines
Authors: De Benedictis F. , Schultz K. , Armstrong C. D. , Javora P. , Qu Q. 
Published: June 2014

Abstract
Water for field operations, usually obtained from available sources close to location, often contains high concentrations of bacteria. In order to ensure that bacteria that might cause formation damage, corrosion, pore plugging, or souring is not introduced into the wellbore, bactericide is often added to source waters. However, when used to dilute brines to lower salt concentrations, the addition of bactericide is based on the resulting salinity of the brine.
Laboratory studies were conducted with various brines and densities to determine when the use of a bactericide is necessary to ensure that bacteria-free brine is introduced into the wellbore. Various brine samples were contaminated with field water containing bacteria and the viability of the bacteria was observed periodically for 48 hours. Results indicated that the viability of bacteria was dependent on the nature and type of brine (NaCl, CaCl2, NaBr, CaBr2, KCl, and ZnBr2), the concentration of salt in the test brine, and exposure time of the microorganism to the brine. A minimum exposure time was required to effectively kill bacteria, and this requirement will be discussed in relation to operational parameters and fluid inhibition issues. The mechanism of microbiological vitality of high osmotic conditions will also be discussed.
Effective Kaolinite Damage Control under Unfavorable Chemical Environment: Field Case
Authors: Restrepo A. , Lastre M. , Milne A. , Peñaloza S. J , Castro E. 
Published: June 2014

Abstract
Kaolinite migration is a common but often well treated formation damage mechanism. Undesired secondary reactions leading to precipitates and/or limited treatment coverage related to the presence of additional damage mechanisms are common issues. The present work documents a field case study of kaolinite damage control that included dissolution and stabilization under a very unfavorable environment in which CaCO3 scales and asphaltenes also co-existed. The case herein described is the last development stage after several unsuccessful trials in the same area which included the injection of conventional mud acid and retarded HF sandstone type systems. A new chemistry approach incorporating retarded flouboric acid generation and high performance chelants for metallic ions control was developed. Also key, was realizing fines wettability to oil (through critical rate tests to both water and oil) which allowed including proper pre-flushes on final treatment deployment.
Along with a summary of the fines problem description in the area of interest, laboratory protocols, stimulation design approach and field trial results are presented. According to treated well results, up to 50% PI improvement could be now attained in ~60% of total well count where same damage configuration is expected to be present.
Development of More Environmentally Friendly Demulsifiers
Authors: Zhou Hui , Dismuke Keith I. , Lett Nathan L. , Penny Glenn S. 
Published: June 2014

Abstract
Formation damage caused by water-in-crude oil emulsions can have a big impact on oil production. Chemical treatment is often applied by injecting surfactants known as demulsifiers to break the water-in-crude oil emulsions. Common demulsifiers used in the oilfield industry often contain chemicals that are deemed environmentally unacceptable. With the increasingly stringent environmental and safety measures for oilfield chemicals, there is a significant drive to develop more environmentally friendly formulations for oilfield applications that are as efficient as existing chemicals. In this work, more environmentally friendly demulsifiers have been developed by systematically upgrading existing components in a conventional demulsifier with more environmentally acceptable components. The environmental impact of existing and upgraded formulations was evaluated using industry developed product rating systems. Demulsification tests were then carried out to assess the performance of the newly developed formulations on several problematic oils.
Novel Interconnected Bonded Structure Enhances Proppant Flowback Control
Authors: Burukhin A. , Kalinin S. , Abbott J. , Bulova M. , Wu Y. , Crandall M. , Kadoma I. , Begich M. , Papp S. 
Published: June 2014

Abstract
Loss of proppant from the near wellbore region of a fracture results in fracture pinch out and a noticeable decrease in well productivity. Downhole and surface equipment can be damaged when proppant flowback occurs as well. Resin coated proppant (RCP), fibers, deformable particles, resin on the fly, etc have been used to improve proppant pack stability. Selection of the appropriate proppant flowback control technology is made with consideration of engineering factors such as fluid compatibility issues, setting time, resistance to cycling stress-loading issues, and conductivity damage.
The goal of the current work was to combine the beneficial features of mechanical proppant flowback control with chemical adhesive flowback control products. With mechanical features, the proppant pack stability is enhanced by blending fibers with proppant, thus increasing particle-particle interaction, and increasing the stability of proppant arches. This mechanism can enable aggressive flowback while providing an instantaneous, albeit a modest level of proppant flowback control. With the addition of an adhesive bonding mechanism to a mechanical flowback control material, the bicomponent material substantially increases proppant pack stabilization. Using a high temperature, high pressure proppant flowback control apparatus, we show the impact of particle bonding on the dosing required to achieve a specific level of proppant pack stability. We also show the impact of the flexible nature of bonded matrix on the proppant pack stability and tolerance to cyclic loading.
A mechanistic proppant pack stability model was developed based on our experimental study. We discuss this model and its application towards the selection of the appropriate proppant flowback control technology for specific well conditions. We conclude the paper by discussing field cases of effective proppant flowback prevention techniques deployed as a result of model recommendation.
Extending Reamer Life and Improving Drilling Performance by Optimizing Neutral Points in Bottomhole Assemblies
Authors: Krishingee Roxann J , Ulmer Karl , Posey Byron 
Published: June 2014

Abstract
With the development in drilling technology, operators are now drilling further into unknown temperature and pressure regimes, extending the typical well depth to limits never seen before. To deal with these unseen depths, wellbores are being re-designed with more casing strings. Consequently, under-reamers are being used much more frequently to help achieve the optimum hole size for casing.
In bottomhole assemblies (BHAs) with under-reamers it is not unusual to have two neutral points in the assembly, creating a transition zone between both neutral points. To comprehend the effects of placing a reamer in this transition zone, some field cases with reamers placed in this zone were studied. Based on the findings, the reaming bottomhole assembly was optimized to eliminate dual neutral points, which resulted in extended under-reamer life.
This paper discusses the benefits of optimizing hole-opener placement in regards to neutral points and the transition zone. Some precautionary procedures are mentioned that can be implemented to optimize bottomhole assemblies that include reamers, reduce BHA failures and improve drilling efficiency.
Optimizing Borehole Imaging for Tight Gas Exploration: Evolving a Go-No-Go Decision Tree in Tight Gas Reservoirs of the Sultanate of Oman
Authors: Shrivastva Chandramani , Al-Mahrooqi Sultan , Mjeni Rifaat , Kindy Suleiman , Hosein Feraz , Al-Busaidi Hafidh , Al-Busaidi Jokha , Laronga Robert 
Published: June 2014

AbstractBorehole images play a crucial role in tight gas exploration. Recognition of sedimentary features helps in understanding the depositional architecture and allows refinement of the facies model for flow unit identification and stimulation treatment. The structural analysis of faults and fractures provides clues not only about the tectonic history, but also about the possible conduits for fluid migration that lead to diagenesis. The diagenetic imprints and their impact in a sequence stratigraphic framework can be understood through textural analysis performed on the borehole images across the field. And, hydro- fracturing of tight gas reservoirs require important input from the borehole images in understanding the variability of stress regimes.Established micro-resistivity imagers for the water-base mud (WBM) environment provide robust results, except when there is a large contrast between the formation resistivity (Rt) and the mud resistivity (Rm). With more frequent use of hyper-saline mud, a new and improved definition imager is deployed to obtain high quality images. Novel hardware and improved signal processing algorithms are employed to acquire the images despite the hostile conditions provided by the combination of low- resistivity salt-saturated (WBM) and high formation resistivity that would otherwise impede the data quality. Early field testing of this enhanced capability took place in the Sultanate of Oman and the examples of its improved performance are presented.Getting the most detailed image data in oil-base mud (OBM) is challenging compared to the WBM systems. As an alternative to the options commercially available in the industry today, the new high-definition imager developed for the WBM system can also be used under favorable conditions to acquire valid images in the OBM. The high-definition imager works best in OBM when both formation resistivity and mud permittivity are high.A workflow is developed for the Go – No Go decisions for borehole imaging tools in different mud systems for tight gas reservoirs. It is important at the planning phase of the logging programs to anticipate the imaging tool behavior in the proposed mud system and conditions. The results from trials made in the tight gas reservoirs of North Oman provided the basis for a decision tree for imaging, since the logging environment exerts a strong control on data quality. The decision-tree presented here aims to ensure that images acquired are the most suitable for detailed geologic interpretation and subsequent integration in development plans for optimal exploitation of tight gas sands in Oman.
The Linear Displacement of Oil from Porous Media by Enriched Gas
Authors: Welge H.J. , Johnson E.F. , Ewing S.P. , Brinkman F.H. 
Published: June 2014

Abstract
This paper presents a method for predicting the manner in which oil will be displaced from a porous body by enriched gas. The calculations apply to a gas rich enough to give a partially, but not a completely, miscible displacement. The method - a three-component, two-phase analysis - takes into account condensation of some of the intermediate hydrocarbons from the injected gas into the oil, as well as enhanced volatility of heavier hydrocarbons at elevated pressures and temperatures. The condensation swells the oil and decreases its viscosity, thus aiding in its recovery.
The calculations have been extended to apply to actual crude oil-natural gas systems by arranging the components into three groups according to their volatility. As an approximation, each group is then treated as a single component in the analysis. The influence of an angle of dip for an inclined displacement is also taken into account.
The recovery predictions are corroborated by experiments which used both consolidated sand cores and unconsolidated glass beads. In some of these tests, actual live crude oil was displaced by amulticomponent gas typical of enriched gases used in oil fields.

Introduction
This paper presents a method for predicting the amount of oil that can be displaced from a homogeneous, linear, porous body at various stages during the injection of enriched, or "wet", gas. The porous body can be in either a horizontal or an inclined position. This type of displacement is sometimes known as "condensing gas drive". The method is developed especially for the case in which the injected gas is enriched enough to be partially, but not completely, miscible with the reservoir oil. The need for a calculative procedure for this type of operation is emphasized by the number of field projects where completely miscible drives are not practical, but where near-miscible conditions are feasible.
Laboratory Studies of Oil Recovery by Steam Injection
Authors: Willman B.T. , Valleroy V.V. , Runberg G.W. , Cornelius A.J. , Powers L.W. 
Published: June 2014

Abstract
This paper reports the results of an investigation into the use of steam as a recovery agent. High oil recoveries by steam, as much as 100 per cent greater than by water flood, were demonstrated in laboratory linear cores. The principal mechanisms responsible for the additional oil have been identified asthermal expansion of the oil,viscosity reduction andsteam distillation.
Although the first two also enhance recovery by hot water flood, they are effective with steam injection at lower volumes of produced fluids. Steam-zone residual oil saturation is independent of initial saturation. Recovery by steam is greater for lighter oils because they contain a greater fraction of steam-distillable components. Equations for the steam-zone advance in a radial homogeneous system are presented; these show the effect of reservoir parameters. The displacement in the hot liquid region moving ahead of the steam front can be estimated by a calculative procedure which is suggested. The method which takes account of the temperature gradient is applicable also to a regular hot water flood.

Introduction
Considerable industry interest in the application of heat to petroleum reservoirs as a means of increasing oil recovery has been evident in the past few years. Three thermal methods which have attracted interest arethe injection of saturated steam,the injection of hot water andthe injection of air into a formation to support combustion within the reservoir.
Much has been published in recent years on underground burning, and there have been several papers on hot water injection. Although there are several early reports on steam injection, no recent experimental studies have been published on this recovery method. In our early thermal methods research, a marked improvement was found in oil recovery by steam injection compared with recovery by water injection in the same system. An investigation subsequently was undertaken to obtain quantitative information from which to evaluate steam injection as an oil recovery method. In addition, it was desired to investigate the recovery mechanism of hot water as compared with that of "cold" water and steam injection. An understanding of the mechanisms by which these processes operate would generally define favorable field conditions for their successful application. This paper reports the results of the laboratory study and suggests calculative approaches to estimate the field behavior of the steam-injection process.
Wellbore Solids Removal Coiled Tubing and Vacuum Technology in Heavy Oil Horizontal Wells in North Central Alberta
Authors: Parra A. A. , Bosilca D. 
Published: June 2014

Abstract
Recently a new coiled tubing technology has been used to clean out horizontal wellbores with a low downhole pressure. This technique uses a dual coiled tubing string and a special vacuum tool designed to create a pressure drop across the formation sand face in order to clean out formation fines, unwanted fluids and solids. The work string, used for this application, has a rectangular matrix design; the two 1-1/2"coiled tubing strings are encapsulated into one uniform body using a high strength thermoplastic jacket. The power fluid is circulated down through one of the strings and the returns, including fines and solids, are transported to surface, up the second string. To operate the system, a custom coiled tubing reel, with two rotating joints was designed. The fluid goes through a jet pump (BHA), where it passes through a nozzle creating a "Venturi effect". New software has been developed to simulate the torque and drag, given that the cross section area is similar to a rectangle and it has two contact points, instead of one. A hydraulic simulation has been performed to determine the jet pump performance, circulation rates and pressures. Real time data was used to calibrate the models.
The technology has been used for liner clean outs, in horizontal heavy oil (8 API) wells, with low pressure averaging 362 psi at 2625 ft (2.5 MPa; 800 m TVD; ) reservoirs.
In the first well, 656 feet (200 meters) of 5-1/2" horizontal slotted liner was cleaned out down to 3008 feet (916 meters) and 4.7 barrels (745 liters) of sand were circulated out to surface (30% of the total internal volume). In the first well the production was recovered from an initial rate 6 bbls/day to 31 bbls/day (1 m3/day to 5 m3/day). In the second well, with 5% H2S, the dual coiled tubing was run in the 4- 1/2" production tubing and the 4-1/2" horizontal slotted liner was cleaned out down to 3550 feet (1082 meters).
Based on the results, this technology is proven to be a viable solution for cleaning long horizontal wells with low bottom hole pressures.
Data Blocking or Zoning: Well-Log-Data Application
Authors: Al-Adani Nabil 
Published: June 2014

Summary
Several statistical techniques have been introduced in zoning sequential data such as well-log data or blocking experimental data. In general, these techniques lack the ability to optimize the predicted zones as per the desired number of blocks or zones. In addition, all these techniques' results depend on the amount of data inclusion in the blocking or zonation process. In this paper, a new method has been introduced to address the blocks or zones optimization and data-amount dependency. The new method also helps in establishing a new approach in estimating the data random error, if not known. This paper does not compare all techniques with the proposed approach. One technique has been selected to highlight the advantages of the proposed method.
An example of a Canadian oil-sand well has been used to demonstrate some applications of the new blocking or zoning method.
Oil Field Chemicals Synergy Upstream Arab Heavy Crude Handling Facilities
Authors: Achuo Kima Enow 
Published: June 2014

Abstract
The presentation key objective is to show how synergizing the use of corrosion inhibitor and demulsifiers has enhanced the performance and optimized the cost of Oil Field Chemical (OFC) treatment at Safaniya Onshore Arab Heavy wet crude handling facilities. The various steps involved in synergizing the use of oil field chemicals at Safaniya Onshore Arab Heavy wet crude handling facilities have also been discussed.
The key performance factors used to assess the overall impact of the process including the total cost of chemical treatment, the effective mitigation of corrosion in the system, the oil in water content in the produced water system, other process parameters like emulsion and foaming tendency were addressed.
Synergizing the use of OFC at Safaniya Onshore Arab Heavy wet crude handling facilities has resulted in chemical treatment cost savings of approximately $2.0 MM per year, better treatment of produced water system and improved corrosion mitigation efficiency of 99.6%.
Maximum Permissible Dog-Legs in Rotary Boreholes
Authors: Lubinski Arthur 
Published: June 2014

Abstract
In drilling operations, attention generally is given to hole angles rather than to changes of angle, in spite of the fact that the latter are responsible for drilling and production troubles. The paper presents means for specifying maximum permissible changes of hole angle to insure a trouble-free hole, using a minimum amount of surveys. It is expected that the paper will result in a decrease of drilling costs, not only by avoiding troubles, but also by removing the fear of such troubles.

Summary, Conclusions, and Recommendations
Excessive dog-legs result in such troubles as fatigue failures of drill pipe, fatigue failures of drill-collar connections, worn tool joints and drill pipe, key seats, grooved casing, etc. Most of these detrimental effects greatly increase with the amount of tension to which drill pipe is subjected in the dog-leg. Therefore, the closer a dog-leg is to the total anticipated depth, the greater becomes its acceptable severity.
Very large collar-to-hole clearances will cause fatigue of drill-collar connections and shorten their life, even in very mild dog-legs. Another finding regarding fatiguing of collar connections in dog-legs is that rotating with the bit off bottom sometimes may be worse than drilling with the full weight of drill collars on the bit, mainly in highly inclined holes when the inclination decreases with depth in the dog-leg.
Means are given for specifying maximum dog-legs compatible with trouble-free holes. An inexpensive technique proposed is to take inclinometer or directional surveys far apart; then, if an excessive dog-leg is detected in some interval, intermediate close-spaced surveys are run in this interval.
The application of the findings should result in a decrease of drilling costs, not only by avoiding troubles, but mainly by removing the fear of such troubles. The result would be much more frequent drilling with heavy weights on bit, regardless of hole deviation.