bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evolution of the Snorre Field Downhole Completion Systems
Authors: Gunnarsson Bengt , Tønnesen S. H. , Stensland J. F. , Haut R. C. 
Published: December 2007

Abstract
This paper discusses the development and evolution of cost-effective downhole completion systems for the Snorre Field Tension Leg Platform (TLP) and Subsea Production System (SPS). Included is a discussion of operational experiences that influenced the evolution. Also included in the paper are specific examples of how the completion times were reduced.
Dual-Completion Design for HP/HT Corrosive Oil Well, Villafortuna-Trecate Italy
Authors: Cerruti S. E. 
Published: December 2007

ABSTRACT
Villafortuna-Trecate ( Italy ) oil field is one of the deepest hydrocarbon deposit in production with a reservoir pressure over 15 Ksi, bottom hole temperature in the range of 380 °F and corrosive environment due the presence of carbon dioxide and hydrogen sulphide in the production fluids.
The design of Villafortuna-Trecate completions requested effort in the selection of appropriate equipment and materials that would enhance the safety, longevity and production capacity of the wells.
The paper will discuss the dual completion design outlining the supporting logic and concepts together with the equipment innovations utilized.
It includes discussion on tubing material and design, tubing connection, wellhead equipment, completion schemes and related equipment, annulus fluid and displacement technique. Quality control aspects are also discussed.
It should serve as a general example of conditions unique to deep, high pressure, high temperature corrosive wells and should be of interest to engineers facing a similar task.
"Simpler": A Cost-Effective Re-Engineering of Drilling Operations
Authors: Guicheney P. B. , Mehra Sachin 
Published: December 2007

ABSTRACT
Across the industry ways are being sought to find and extract oil and gas more cost effectively, while improving safety and environmental performance.
Drilling operations are not immune to this scrutiny, yet for the past fifty years there has been little fundamental questioning of how the drilling process is organised. Today the ever-increasing need for more cost-effective operations is bringing such questions to the fore.
The Simpler project, after a review of a wide range of issues related to the well construction process aims at developing an innovative approach to drilling operations resulting in significant costs savings.
The basis of this novel approach is to "Re-Engineer" and integrate well construction activities.
To demonstate it and maximise results, a fit for purpose rig design is presented which also targets enhancements in safety and environmental results.
Solving Gas Lift Problems in the North Sea's Clyde Field
Authors: Pucknell J. K. , Goodbrand Shona , Green A. S. 
Published: December 2007

ABSTRACT
Gas lift wells in the Clyde field have a history of problems, described in this paper.
Due to high temperatures (300 degrees F), the use of corrosion inhibitors and asphaltene dissolvers, it was necessary to use gas lift valves containing high temperature elastomers. These were not always effective at maintaining the nitrogen charge at the correct pressure which resulted in unloading valves opening intermittently causing unstable flow.
Valve failures were not the only for reason unstable flow, other causes included: the use of an orifice valve with a port size which was too large;opening of unloading valves because tubing pressures were higher than expected.
The latter effect occurred because the multiphase pressure drop correlation, while reliably predicting bottom hole pressure, was less accurate in predicting pressures at the depth of the unloading valve. When the tubing pressure profiles were measured with gauges a further problem became apparent. The pressure at a given depth did not remain constant but oscillated about a mean due to normal slug flow. If the opening pressure of an unloading valve is set too close to the tubing pressure, these oscillations can cause unloading valves to open unexpectedly.
These and other problems have been corrected. Firstly, spring loaded valves with factory sealed bellows have been installed. The elastomers’ integrity in these valves are less critical for reliable valve operation. In addition the lack of temperature sensitivity of their opening and closing mechanism makes unloading more reliable. Secondly, a more conservative gas lift design policy is now used, so that despite fluctuating or uncertain tubing pressures, or slight changes in the valve set pressures, unloading valves do not open.
Finally, to ensure that planned gas lift designs are stable, they were also checked using a transient multiphase flow simulator specially constructed to model gas lift wells. The simulator appears effective at predicting when stability problems can be expected.
The paper also comments on corrosion in the gas lift wells, a problem that was anticipated. Calliper surveys and other data suggest that it is unlikely to result in workovers in the near future.
Hydraulic Fracturing in Medium-High Permeability Reservoirs: Methodology and Economic Advantages of Properly-Executed Jobs
Authors: Cleary M. P. 
Published: December 2007

ABSTRACT
Recent (companion) publications have isolated some major new conclusions which have effectively led to reversal of many conventional practices in hydraulic fracturing: these conclusions are based on analysis of field data vs. erroneous theories which had influenced previous efforts. A prime example of such reversal is our conclusion that overall proppant concentration (i.e. total proppant over total fluid volume pumped) should vary essentially inversely with reservoir permeability. Other issues have been demonstrated by recently-published case-studies of fracturing in low-permeability reservoirs. This paper will extend that discussion to medium-high permeability applications, i.e. to gas (oil) reservoirs of order 1-10 (10-100) mD or more.
This paper will also emphasize many major unrealized and/or poorly-rationalized aspects of such fracturing operations: these will include identification and execution of adequately-packed fractures ("pack-fracs" vs. common near-wellbore "frac-packs"); related work has quantified the dominant role of permeability variation in fracture growth/geometry. It will be indicated that many of the common/expensive problems associated with correspondingly mal-designed/executed field operations may be easily remedied: primary among these concerns are premature screen-outs/wash-outs and proppant production problems.
This paper will also demonstrate the tremendous (incremental) economic benefits of fracturing most wells, especially where variable petroleum demand/price have made capital investment decisions difficult (and often foolish, at least in retrospect). Appropriate use of the right technology also serves to reduce (correctly/actuarially - accounted) risk, certainly when properly executed to avoid the common problems which have plagued previous experiences; proper execution should alsa serve to remedy unfulfilled claims/promises, which have previously hindered widespread hydraulic fracturing technology application. Reliable fracturing capabilities now create major new (overall project) options for/and greatly improved investment strategies.
Description and Performance of a Lacustrine Fractured Reservoir
Authors: Deo M. D. , Neer L. A. , Whitney E. M. , Nielson D. L. , Lomax J. D. , Pennington B. I. 
Published: December 2007

Abstract
The main sand body in the Travis unit, located in east-central Utah, is Lower Douglas Creek (LDC), the lowest portion of the Green River Formation. Recent research has revealed that LDC is a lacustrine sloped and basin reservoir. In this paper, reservoir characteristics of the Travis unit are presented along with a history match of primary recovery. Dual-porosity, dual-permeability representation was chosen for the reservoir based on the information from borehole imaging logs. The primary production history match was satisfactory. Response to a water flood has been disappointing to date. The reservoir model which matched primary production was unable to predict the slow response to the water flood. This was attributed to an inadequate understanding of the fracture network in the reservoir.
Mitigation of Reservoir Souring—Decision Process
Authors: Kalpakci Bayram , Magri N. F. , Ravenscroft P. D. , McTeir M. D. K. , Arf G. T. 
Published: December 2007

ABSTRACT
In this paper a general H2S decision strategy, describing the types of information which should be gathered and decisions to be made addressing an existing H2S problem, or new field development is presented.
Taking H2S into consideration in initial facility design, types of monitoring of H2S that should be carried out during field development and exploitation will be discussed. The usefulness of computer phase modelling, including equation of state calculations, to determine H2S concentrations in all phases from reservoir through the production stream will also be described. From quantification of the souring problem it can then be decided if, and where in the production stream, the use of sulfide scavengers is required. A laboratory based testing procedure will be presented, along with experimental data.
In addition to consideration of the basic chemistry, results of an industry survey will be presented on the best applications for commmercial sulfide scavenging products.
Carbon Black: A Low Cost Colloidal Additive for Controlling Gas-Migration in Cement Slurries
Authors: Calloni Giuseppe , Moroni Nevio , Miano Fausto 
Published: December 2007

ABSTRACT*
The effect of different additives on the permeability of cement slurries to formation gas has been studied with the aid of a gas flow apparatus. The performance of two commercial additives (polymer latex and silica fume) has been compared to that of a novel additive (carbon black) that has been developed in our laboratories with the aim of simplifying the cement slurry composition and reducing field operational costs. Data on the thickening time, fluid loss, rheology and compressive strength are also presented to provide a clear picture of the potential of carbon black as a substitute for silica fume and polymer latex in some field applications. Finally, the paper describes the results of a field application using carbon black as a gas-block additive in the cement slurry.
Development of a Complex Type of Pour Point-Viscosity Depressant and Infrared Spectrum Research
Authors: Fusheng Zhang , Biao Wang 
Published: December 2007

Abstract
EMS, a complex type of pour point-viscosity depressant for crudes, is composed of EVA, MVA and Surfactant. After adding EMS into the crudes, a very nice result in reducing pour point and viscosity for Daqing, Jianghan and Jidong crudes was got. From the research result of infrared spectrum of interaction between EMS or its components and wax or mixture of resin and asphaltene isolated from three crudes above-mentioned, it has been shown that the area ratio of the double absorption peaks of 719 cm−1 and 729 cm−1 or 1388 cm−1 and 1378 cm−1 changed remarkably after EMS or its components were added into wax. It can be infered that the cocrystallization probably happened between the EMS or its components and the wax. The position of 4000-3000 cm−1 infrared absorption peak of the mixture of resin and asphaltene moved to the lower wavenumber, and the ratio of the area of 1373 cm−1 absorption peak (methyl) to the combination area of 748,810 and 871 cm−1 absorption peak (aromatics) increased remarkably. It can be infered that the pour point-viscosity depressant molecules destroyed the original hydrogen bonds and overlapping of the aromatic ring planes among resin and asphaltene molecules to form new cubic molecular structure and new hydrogen bonds. With the results the viscosity of crude oil will be reduced.
A New Iterative Solution Method With Alternating Interblock Direction (AID) Preconditioner
Authors: Shin Dalsoo 
Published: December 2007

ABSTRACT
This paper presents a new iteration method for the numerical solution of pressure equations arising in petroleum reservoir engineering. It utilizes a newly developed preconditioner and generalized conjugate gradient acceleration with a new residual constraint procedure. The Alternating Interblock Direction (AID) preconditioner exploits a natural way of alternating sweeps in xyz-directions and is free from the dependence on the choice of the first internal direction which is common with other methods. The generalized conjugate gradient algorithm is ORTHOMIN. It is further accelerated by an alternating direction residual constraints (ADC) which could make the summation of the residuals be zero simultaneously in all three axes. The new method can be easily vectorized and parallelized. It can also be adapted to equations other than the pressure equation. Its speed and robustness are proved to be favorable to previously published methods by numerical experiments.
Static and Dynamic Load-Balancing Strategies for Parallel Reservoir Simulation
Authors: Anguille Luc , Killough J. E. , Li T. M. C. , Toepfer J. L. 
Published: December 2007

Abstract
Accurate simulation of the complex phenomena that occur in flow in porous media can tax even the most powerful serial computers. Emergence of new parallel computer architectures as a future efficient tool in reservoir simulation may overcome this difficulty. Unfortunately, major problems remain to be solved before using parallel computers commercially: production serial programs must be rewritten to be efficient in parallel environments and load balancing methods must be explored to evenly distribute the workload on each processor during the simulation.
This study implements both a static load-balancing algorithm and a receiver-initiated dynamic load-sharing algorithm to achieve high parallel efficiencies on both the IBM SP2 and Intel IPSC/860 parallel computers. Significant speedup improvement was recorded for both methods. Further optimization of these algorithms yielded a technique with efficiencies as high as 90% and 70% on 8 and 32 nodes, respectively. The increased performance was the result of the minimization of message-passing overhead.
Compositional and Black Oil Reservoir Simulation
Authors: Coats K. H. , Coats K. H. , Thomas L. K. , Pierson R. G. 
Published: December 2007

Abstract
This paper describes a three-dimensional, three-phase reservoir simulation model for black oil and compositional applications. Both IMPES and fully implicit formulations are included. The model's use of a relaxed volume balance concept effectively conserves both mass and volume and reduces Newton iterations. A new implicit well rate calculation method improves IMPES stability. It approximates wellbore crossflow effects with high efficiency and relative simplicity in both IMPES and fully implicit formulations. Multiphase flow in the tubing and near-well turbulent gas flow effects are treated implicitly.
Initial saturations are calculated as a function of water-oil and gas-oil capillary pressures which are optionally dependent upon the Leverett J function or initial saturations may be entered as data arrays. A normalization of the relative permeability and capillary pressure curves is used to calculate these terms as a function of rock type and grid block residual saturations.
Example problems are presented, including several of the SPE Comparative Solution problems and field simulations.
Rabi Multi-Sector Reservoir Simulation Model
Authors: Bruijnzeels Chris 
Published: December 2007

Abstract
To ensure optimum ultimate recovery of the 46 meter thick oil rim of the Rabi Field in Gabon, a full field simulation model was required. Due to it's size and complexity, with local cusping, coning and geological circumstances dominating individual well behaviour, a single full field model would be too large for existing hardware. A method was developed to simulate the full field with 5 separate sector models, whilst allowing the development in one sector model to have an effect on the boundary conditions of another sector. In this manner, the 13 x 4.5 km field could be simulated with a horizontal well spacing down to 175 meter.
This paper focuses on the method used to attach single 3-phase tank cells to a sector simulation grid in order to represent non-simulated parts of the field. It also describes the history matching methodology and how to run a multi-sector model in forecasting mode.
This method can be used for any reservoir, where size and complexity require large reservoir simulation models that normally could not be modelled within the constraints of available computer facilities. Detailed studies can be conducted on specific parts of a field, whilst allowing for dynamic flow and pressure effects caused by the rest of the field.
Compositional Reservoir Simulation on CM-5 and KSR-1 Parallel Machines
Authors: Ghori S. G. , Wang C. H. , Lim M. T. , Pope G. A. , Sepehrnoori K. , Wheeler M. F. 
Published: December 2007

ABSTRACT
Recently, use of parallel machines in reservoir simulation has received considerable attention from the petroleum industry. This paper presents parallelization of a 3D compositional, equation-of-state reservoir simulator on the CM-5 and KSR-1. To the best of our knowledge, this is the first time that the parallelization of a compositional reservoir simulator has been performed on both the CM-5 and KSR-1.
For new users of the CM-5 machines, the software and hardware of CM-5 architecture is presented, as well as details of the parallelization techniques. For example, domain decomposition, I/O's, phase equilibrium computations, and well model are described. The parallelism techniques on the KSR-1 are presented with the emphasis on the porting of the phase equilibrium calculation.
The performance of each machine is evaluated by showing the speedup on different sets of processing nodes. Two test problems were used to explore the capability of the parallelized version of the code; one is a waterflood problem and the other is a CO2 multiple contact miscible flood, both in a West Texas oil field. These field problems were run on 1, 2, 4, 8, 16, and 32 processors to get insight into the locations of communication bottlenecks, generally occurring in the programming with distributed memory machines. The problems of latency and bandwidth which are associated with communication efficiency of the CM-5 are also addressed.
Commercial Valuation of Hydrocarbon Resources
Authors: Boardman John S 
Published: December 2007

ABSTRACT
A practical business process is described which enables all categories of hydrocarbon resources to be valued in a commercially consistent manner. The benefits of the process are increased if there is a transparent corporate strategic plan which can be used to test the value of a resource against a desired portfolio, described quantitatively in terms of value and risk. Individual opportunities for both acquisition and disposal can then be measured against an assessed "Corporate preference profile" and pursued with increased confidence in the overall fit.
The Use of Coiled Tubing During Matrix Acidizing of Carbonate Reservoirs
Authors: Thomas R. L. , Milne A. 
Published: December 2007

ABSTRACT
A laboratory and field study directed at improved well performance of horizontal wells is discussed. During the study, several wells were matrix acidized using bullhead and coiled tubing placement techniques. The study performed in carbonate reservoirs indicates acid placed with coiled tubing diverted with foam provides excellent zone coverage and damage removal. Conventional bullhead techniques do not result in effective damage removal. The study emphasizes the evaluation of the treatment results and the development of improved acidizing techniques.
Laboratory simulations of matrix acidizing indicate proper placement techniques are essential. This observation is supported by field data in oil wells completed in carbonate reservoirs. The key to successful damage removal is 1) the placement of acid via coiled tubing and 2) proper diversion. Production logging and well performance data support this claim.
The proposed treatment is applicable in both horizontal and vertical wells completed in carbonate reservoirs.
New Cement Additives that Eliminate Cement Body Permeability
Authors: Talabani Soran , Hareland Geir 
Published: December 2007

Abstract
An experimental investigation was carried out replacing some currently used cement additives with three new additives.
The experiments performed monitored the cement slurry pressure during the setting of the cement. During the setting period of the cement, two time cycles of cement expansion and contraction are observed. This is due to the individual contribution of each component in the cement mixture. To obtain the optimum tightness of the cement, final contraction in the cycle is crucial for blockage of gas migration. In these studies optimum concentrations of the additives were obtained experimentally, where the cyclic pressure behavior of the cement was optimized and the permeability reduced for the best final cement results. The parameters investigated in this study were; change in the applied pressure on the slurry with time, the compressive strength and permeability of the set cement. The major causes of the early microfractures are the in-complete cement – water reaction, low compressive strength of the set cement, and the sudden change in the hydrostatic pressure as the cement changes its phase from liquid to a solid state1. The fluid loss and free water content were measured and controlled for each sample.
One Of the new additives is used to eliminate the micro-annulus with the pipe and the other two are used to eliminate the micro-fractures within the cement body.
The correct Ironite Sponge concentration eliminated the micro-annulus with the pipe. The optimum amount of Synthetic Rubber powder needed during the optimum two cycle expansion-contraction process was also obtained under reservoir conditions.
The Anchorage clay concentration in the mixture that migrates for a limited time minimizes the cement body pores. This concentration can also be optimized.
The results of this study is that proper amounts of X-C polymer, Anchorage clay, Ironite Sponge, and Synthetic Rubber can be used to optimize the compressive strength and eliminate both micro-fracture and micro-annulus. There are certain limits to the amount and type of Synthetic Rubber powder which cement will set and the micro-fractures are eliminated. This experimental approach can be used to eliminate gas migration through a cement design that is environmentally safe, inexpensive, and uses recyclable materials.