bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use Of Inert Gases In Well Completions
Authors: Horton Harry L. , Moran J.P. 
Published: December 2007

Abstract
Nitrogen and carbon dioxide have proved to be very effective production tools. In many fracturing and acidizing jobs, the use of one of these inert gases along with the stimulation fluid has improved the efficiency of the treatment, and sometimes made the treatment possible.
A review of case histories of many jobs using nitrogen and carbon dioxide as completion aids shows clearly the value of this technique as it is presently being used.
Before nitrogen and carbon dioxide could be put to use by the oil industry, it was necessary to develop special equipment that could move and handle them in the field. Now that this has been done, research efforts are being directed toward finding out more about the effects of these gases under simulated reservoir conditions so that present treating techniques can be improved even further.
Introduction
As early as January, 1938, portable well-service equipment was available for supplying limited quantities of low-pressure (100 psi) gas to aid in well-stimulation treatments.
Although the use of compressed gas increased the efficiency of acid stimulation treatments, use of the portable compressors limited this application to low-pressure wells where a low-rate treatment or a low gas-to-acid ratio was sufficient to help in return of the spent-acid solutions. High-pressure wells could be treated by this method only when a source of high-pressure gas was close to the well being treated. The weight and cost of a portable high-pressure, high-volume gas compressor for general field service made such a unit impractical.
Suspension Properties of Polymer Fluids Used in Drilling, Workover, and Completion Operations
Authors: Carico Robert D. 
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc.
This paper was prepared for the Improved Oil Recovery Symposium of the Society of Petroleum Engineers of AIME, to be held in Tulsa, Okla., March 22–24, 1976. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copied. The abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made. provided agreement to give proper credit is made. Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and with the paper, may be considered for publication in one of the two SPE magazines.

Abstract
The ability of a fluid to suspend particles is essential to the successful particles is essential to the successful performance of fluids used in drilling, performance of fluids used in drilling, workover, and completion operations. The evaluation of a fluids-suspension ability has been by a comparison of the fluids' API Yield Point or by some apparent viscosity (i.e., funnel viscosity or viscometer apparent viscosity). This paper will present a simple, easy-to-use paper will present a simple, easy-to-use test for evaluating the suspension ability of a fluid, will give a ranking of some polymer fluids by their suspension ability, and will relate this ability to a low-shear-rate viscosity measurement of the-fluid.

Introduction
Fluids perform a variety of functions in drilling operations, including:Lift formation cuttings to the surface.Control subsurface pressures.Drill-string lubrication.Bottomhole cleaning.Provide an aid to formation evaluation.Provide protection to formation productivity.Prevent caving of formation.
The ability of the fluid to suspend particles is essential to the successful particles is essential to the successful performance of several of these functions. performance of several of these functions. This suspension capability is also important in other petroleum operations; for example, workover fluids and sand suspension in gravel packing and fracturing.
The evaluation of fluids for their suspending abilities has usually been by a comparison of their relative API yield points (YP) or by some apparent viscosity measurement; i.e., funnel viscosity or viscometer apparent viscosity (AV). Two main problems are encountered in using either of these methods. Firstly, it is almost impossible to compare fluids with different rheologies.
Investigation of Sulfide Scavengers in Well Acidizing Fluids
Authors: Nasr-El-Din H. A. , Al-Humaidan A. Y. , Fadhel B. A. , Frenier W. W. , Hill D. 
Published: December 2007

Abstract
This paper describes the development of acidizing systems that use several different aldehyde-based sulfide suppression chemicals in conjunction with new acid corrosion inhibitors. Specific combinations of these chemicals have allowed the acid to dissolve FeS, suppress H2S and still enable the acid to be inhibited to industry corrosion standards. Laboratory tests include dissolution of FeS, measurement of H2S evolved, measurement of acid concentration and chloride ion concentrations. We also determined the effect of FeS and H2S on the corrosion of oilfield steels with these additives. Laboratory measurements covered the temperature range from 75 to 275 °F (reservoir temperature).
Experimental results were compared with that previously published data.1 The new system enabled the acid to dissolve more FeS than fluids containing previously tested suppressors, while controlling H2S evolution and corrosion.
During field testing, samples of the spent acid were captured and were analyzed for [Fe], [S2−] and [HCl]. The data will contribute to an understanding of the corrosion processes and sulfide control during acid treatments. The field acid treatments were accomplished successfully without significant changes in procedures and resulted in large increase in gas production. This system is designed primarily for "tube cleaning" operations prior to acid stimulation (matrix and fracture acidizing), but the control chemicals have also been tested for use in the actual stimulation fluid stages.
The new chemicals and procedures will allow the operators to safely remove large amounts of fouling deposits, while controlling the toxic and corrosive effects of H2S much more effectively than previously used products.
Sand Production Prediction in High Rate, Perforated and Open-hole Gas Wells
Authors: Ong Seehong , Ramos Rico , Zheng Ziqiong 
Published: December 2007

Abstract
This paper presents an analytical model for the prediction of the on-set of sand production or critical drawdown pressure (CDP) in high rate gas wells. The model describes the perforation and open-hole cavity stability incorporating both rock and fluid mechanics fundamentals. The pore pressure gradient is calculated using the non-Darcy gas flow equation and coupled with the stress-state for a perfectly Mohr-Coulomb material. Sand production is assumed to initiate when the drawdown pressure condition (i.e. at CDP) induces tensile stresses across the cavity face. Both spherical and cylindrical models are presented. The spherical model is suitable for cased and perforated applications while the cylindrical model is used for a horizontal open-hole completion.
For input, the model requires cohesive strength and an internal friction angle that characterizes a Mohr-Coulomb material; preferably predicted using a log-based mechanical properties algorithm in order to generate a foot-by-foot profile of the maximum sand free drawdown for gas wells. The example GOM well illustrates a continuous profile of critical drawdown with depth, providing quick identification of potential sand producing zones. This allows a gravel pack decision to be made in the period between logging and completion. It also facilitates the design of selective perforation programs.
The model demonstrates that non-Darcy flow has a considerable effect on the sanding tendency of weak but competent rock, and completion decisions in high gas-rate wells that neglect the influence of non-Darcy flow could be overly optimistic. It also shows that the CDP of a horizontal well with slotted liner is less than that of the corresponding cased and perforated completion.
Predictability of Porosity and Permeability Alterations by Geochemical and Geomechanical Rock and Fluid Interactions
Authors: Faruk Civan 
Published: December 2007

Abstract
This paper presents improved models for interpretation, correlation, and prediction of the variations of permeability and porosity in petroleum-bearing rock, in which the pore topology is evolving by geochemical and geomechanical rock and fluid interactions during formation damage and stimulation processes. The permeability and porosity relationships considering pore evolution by precipitation and dissolution, and stress and temperature variation are developed. The present approaches are demonstrated and verified by analyzing a variety of reported data and shown to lead to accurate and functionally well behaving correlation. The applications demonstrate that the improved dynamic models accurately predict the measured porosity and permeability data. The associated analysis also lends itself to the physical interpretation of the variation of porosity and permeability in terms of the governing mechanisms.
Global Experiences and Practice for Cold Production of Moderate and Heavy Oil
Authors: Ehlig-Economides C. A. , Fernandez B. G. , Gongora C. A. 
Published: December 2007

Abstract
Today, most operators prefer to exhaust the opportunities for cold production of moderate and heavy oil before embarking on much more expensive and involved thermal recovery processes. Permeabilities of the order of 10’s of Darcies are common. However, the high oil viscosity causes low mobility, and hence, low well productivity. In some cases well productivity is 10–20 times higher than that explained by the usual Darcy’s law flow equations, because sand is produced with the oil ("worm holes"), or because gas in the oil comes out of solution and the gas-oil mixture has unusual flow characteristics ("foamy oil"). Frequently high initial productivity drops very quickly threatening the economic viability of the well. Assembled global experience with these phenomena coupled with critical fluid and rock property data and geological descriptions enables various generalizations to be made about observed production behavior, which, in combination, provide a means to design the optimal cold production strategy for a given reservoir.
Screenless Single Trip Multizone Sand Control Tool System Saves Rig Time
Authors: Hailey Travis , Cox Morris , Johnson Kirk 
Published: December 2007

Abstract
A new system of tools has been developed to complete multiple producing intervals in unconsolidated sandstones during one trip into the well. The system was developed to make efficient use of a previously developed pumping process, which simultaneously incorporates fracturing with proppant, and chemical consolidation of that proppant. The system provides sand control by installing resin coated proppant during the pumping process on each of the production intervals but leaves the casing across those intervals unobstructed except for isolation packers, which can be used for production management during the life of the well.
This new system enables low cost but highly productive completions, specifically enabling small and/or marginally economic reservoirs to be completed along with more valuable reservoirs. Multiple marginal reservoirs may be combined to make an entire project reach minimum required profitability. The system has been designed to allow low incremental cost for accessing additional reservoirs.
The system was used for the first time in the Milne Point field on the North Slope of Alaska in a field operated by BP Exploration (Alaska). This paper will describe in detail the design and operation of this tool system, including component drawings, operational sequence drawings, and a field case history in which the equipment was used.
Pressure-Actuated Isolation Valves for Fluid Loss Control in Gravel/Frac-Pack Completions
Authors: Worlow D. W. , Grego L. V. , Walker D. J. , Green G. R. , Smith B. E. , Harris M. E. 
Published: December 2007

Abstract
A new, mechanical fluid loss control system, integral to the base pipe of gravel pack screens, has been developed for ‘smart’ completions. This system allows for positive fluid loss control through all phases of well work once the gravel/frac pack is in place including the running of the isolation tubing stinger through the upper screen assembly of stacked completions. The isolation valves are opened for production without wireline intervention by hydraulically opening the zonal isolation sleeve of the ‘smart’ completion and applying pressure down the tubing. A new screen coupling system has also been developed to allow fluid returns during gravel/frac pack operations when the pressure actuated valves are run. To date, this system has been designed, tested, and successfully run in two deepwater subsea completions (3200’ WD).
An Economic, Field-Proven Method for Removing Fines Damage from Gravel Packs
Authors: Stanley F. O. , Troncoso J. C. , Martin A. N. , Jamil Omar Ali 
Published: December 2007

Abstract
It’s a fact of life – many gravel packs plug up. As time passes, skin factors go up and production rates go down. Much of the money that was spent on creating a sand control completion with minimum skin may eventually count for nothing. In order to prolong the effectiveness of the gravel pack (GP) and as a added benefit reduce the need for workovers, a method was developed in the Far East to remove these fines and dramatically reduce the skin factor. The method employs relatively small volumes of a specialized HF (hydrogen fluoride) acid system, designed to penetrate into the GP and very near wellbore area. The HF acid system uses an organophosphonate (HV) acid to control the production of HF and to control and drastically reduce potentially damaging secondary and tertiary precipitates. The system will be referred to as HV:HF Acid in this paper.
This HV:HF Acid system can be applied to any well with a screen and/or GP that has damage caused by the migration of formation fines and/or drilling mud particles. It is not limited by the type of screen or gravel nor by the length or number of sets of screens. The method has potentially enormous implications throughout the world. Any well with a GP or screen could potentially benefit from this method of treatment, including long horizontal intervals, which up to now have been very expensive to treat, due to the larger volumes of acid normally recommended.
The results of this HV:HF Acid method will be illustrated by 3 case histories from the Far East, including horizontal wells. The observations from these treatments allow us to conclude that this method is highly successful, cost effective, and applicable to a broad spectrum of well conditions. The reduced stimulation volumes provide better economics, so that even long sections and horizontal wells can now be stimulated at reasonable costs.
Considerations for Conducting Coiled Tubing Well Control Operations to Minimize Formation Impairment
Authors: Sas-Jaworsky Alexander , Ghalambor Ali 
Published: December 2007

Abstract
Coiled tubing services are frequently used to conduct kill operations concentric to existing production tubulars. These kill operations are typically performed to temporarily effect a hydrostatic balance of formation pressure at the exposed completion. Because coiled tubing well control operations are conducted concentric to existing production tubulars, special attention to job design and implementation is critical to ensure proper placement of kill fluids within the wellbore to achieve the desired pressure balance and to minimize the potential of formation damage.
In those cases where wellbore operations subsequent to the kill program are not intended to return the existing completion to active status, formation damage induced by the kill practice is typically of little consequence. However, where return of the existing completion to active status is desired, the well control operation must be conducted with a complete understanding of the pressure balance and effect of kill fluid circulation on the completion. Many practices used in performing concentric tubing well control services lead to vaiying degrees of formation damage and impair completion flow performance.
This paper discusses typical damage mechanisms resulting from completed wellbore kill programs, along with the related formation damage consequences for these types of operations, alternative well control kill processes using coiled tubing and the potential for reducing formation damage by using coiled tubing well control processes. In addition, recommendations for planning and implementing coiled-tubing conveyed well control programs within existing production tubulars are provided to guide the user in conducting well control operations with minimal induced formation damage.
Optimizing the Selection of Bridging Particles for Reservoir Drilling Fluids
Authors: Dick M. A. , Heinz T. J. , Svoboda C. F. , Aston M. 
Published: December 2007

Abstract
Most water-based reservoir drilling fluid systems used today are comprised of four primary components: the base brine, viscosifier, fluid-loss additive, and bridging particles. With the exception of minor adjustments of loading levels, the first three components normally do not change. The two primary types of bridging agents include calcium carbonate and sodium chloride salt. Some companies offer as many as seven different grades or sizes of each type of bridging particle.
For the first time, the "ideal" pigment-size-distribution theory used widely in the paint industry has been transferred to practical oilfield use. This paper discusses the method and its use in selecting the optimum blend of bridging particles, focusing on an ideal packing sequence for minimizing fluid invasion. The authors examine the various procedures for optimizing sealing, as well as a management maintenance system.
The paper expands on Abrams’ Median Particle-Size Rule by going beyond the size of particle required to initiate a bridge. In the discussion, the authors examine the ideal packing sequence for formulating a minimally invading (non-damaging) fluid.
Mechanisms of Mud Cake Removal During Flowback
Authors: Zain Zulkeffeli M. , Suri Ajay , Sharma Mukul M. 
Published: December 2007

Abstract
External filter cakes are used to minimize fluid loss and solids invasion to a formation from drilling and completion fluids. Subsequently, the cake must be removed in order to increase the flow area and minimize skins, especially for openhole and gravel packed completions in horizontal and deviated wells. Experimental data is presented to show that the pressure required to initiate flow into the wellbore after building up a filter cake is affected by rock permeability, mud properties such as particle size and cake yield strength, flow back velocity, and overbalance pressure.
Mud cake lift-off tests, mud particle size, and rock pore throat size distribution measurements were performed to understand the factors that contribute to cake removal. The mechanisms that control filter cake removal are discussed.
In this study, it is clearly shown that the flow initiation pressure during flow back is controlled by solids invasion, i.e. internal formation damage rather than by the external mud cake. Flow initiation pressures show a minimum with increasing rock permeability due to two competing effects. Larger pore sizes result in smaller flow initiation pressures, however, more solids invasion increases ΔPfi. Higher overbalance pressures also increase the internal formation damage and flow initiation pressure. A simple model to calculate the flow initiation pressure during flow back is proposed. The model correctly predicts the experimentally observed trends with rock permeability, mud particle size distribution, extent of solids invasion, and the yield strength of the mud cake. The model provides a systematic method for designing fluids with low flow initiation pressures. It is also shown in this study that low flow initiation pressures do not imply complete cake removal. Cake removal is primarily controlled by the permeability of the cake and its mechanical properties.
Experimental and Modeling Studies on Foam in Porous Media: A Review
Authors: Nguyen Quoc P. , Alexandrov Alexander V. , Zitha Pacelli L. , Currie Peter K. 
Published: December 2007

Abstract
Foams have been used for several decades to decrease the mobility of drive gas or steam, thereby enhancing the reservoir sweep efficiency. More recently foams found application in near-wellbore production enhancement operations such as acid diversion for matrix stimulation, gas shut-off, water shut-off and hydraulic fracturing. The optimization of these operations requires a thorough knowledge of the physical aspects involved in foam flow through porous media. In spite of the copious amount of experimental and theoretical investigations found in the literature, this knowledge is lacking.
The present paper is aimed at reviewing experimental and modeling studies on foams in porous media, to stress the latest achievements and highlight the areas that are the least understood. The focus of the analysis is twofold. First, we review the most representative core flow experiments that were undertaken to investigate the behavior of relative permeabilities and mobilities with emphasis on the key microscopic mechanisms proposed. Second, the different classes of models of foam flow through porous media are presented, outlining their advantages and weaknesses. A comparative analysis of the models is presented.
Formation Damage Resulting from Biocide/Corrosion Inhibitor Squeeze Treatments
Authors: Nasr-El-Din H. A. , Rosser H. R. , Al-Jawfi M. S. 
Published: December 2007

Abstract
To control sulfate-reducing bacteria (SRB) populations, and minimize operational problems noted in the water supply wells, a biocide/corrosion inhibitor squeeze program was applied. Because of the weak nature of the formation and potential sand production, an extensive coreflood study was conducted to determine the effect of a commercial biocide (formaldehyde, nitrogen and phosphorous compounds) and a biocide-enhanced corrosion inhibitor on the permeability of reservoir core plugs. Coreflood experiments were conducted using reservoir core plugs at reservoir temperature (50 °C) and pressure (2000 psi).
The results obtained indicated that high concentrations of the biocide or the biocide enhanced corrosion inhibitor caused up to 90% reduction in the initial permeability of reservoir cores. Several damaging mechanisms were identified: dissolution of the cementing material by the biocide (acidic), swelling of montmorillonite present in the formation and precipitation of calcium sulfate. Based on lab results, a detailed biocide squeeze treatment was designed to treat water supply wells. The treatment was able to control SRB populations while maintaining the integrity of the formation. This paper examines the design of the treatment and the results obtained from extensive lab testing and field trials.