bluuebunny/crossref_metadata_2025_split huggingface dataset:
Unique Polycrystalline Diamond Compact (PDC) Cutter Improves Drilling Efficiency
Authors: Wilmot Graham Mensa , Ramirez Javier 
Published: December 2007

Abstract
Advancements in Polycrystalline Diamond Compact (PDC) cutter technology1 have boosted the development and performance of PDC bits. In establishing their contributions to PDC bit performance, cutters have primarily been evaluated in terms of their resistances to impact and abrasion. Additionally, other characteristics such as interface strength, burst resistance, thermal stability and fatigue are also analyzed. Maximizing these properties improves cutter durability2, which subsequently enhances PDC bit performance and drilling efficiency.
Although desirable, the above objectives are not easily attainable. Most of the properties listed above exhibit inverse relationships, therefore maximizing any specific property has normally been achieved at the expense of the others. This caused the industry to focus on the development of technologies that optimize the performance characteristics of cutters3. These efforts have been beneficial, because improvements have been achieved in cutter durability. However, the need to keep extending the application envelopes of PDC bits requires continuous improvements to be made in cutter technology.
A newly developed cutter (NDC) is enhancing PDC bit performance. NDC has a unique geometry, which when applied to any cutter, regardless of size or substrate length, redefines the known relationships between WOB, RPM, Torque and ROP. The geometry, which is defined by the following parameters - offset, tangency, leading and trailing angles - has been stress engineered into NDC's tungsten carbide substrate. When applied to any PDC cutter with optimized performance characteristics, NDC's unique geometry helps establish new standards in PDC bit performance.
The paper will define a new set of performance qualifiers for PDC cutters. It will establish the relationships between NDC's parameters and the effect they have on the drilling operation. Additionally, it will ascertain how NDC's unique geometry enables achievement of the new performance qualifiers. Analytical and field support will be presented to show how NDC improves drilling efficiency.
Surface Axial Load Based Progressive Cavity Pump Optimization System
Authors: Mena L , Klein S. 
Published: December 2007

Abstract
Actual Field tests performed in heavy and extra-heavy oil wells in San Tome, Venezuela reveal that axial load does have a direct relation with Progressive Cavity Pump (PCP) downhole conditions. The differential pressure across the pump is easy to infer by just measuring the surface axial load of the system and surface pressures. This fact is particularly useful to diagnose a PCP (known to be very difficult to do for this system). Good inferences on downhole conditions allow PCP optimization to be done much easier and more efficiently. It has been proven in beam pump applications that the dynagraph chart (axial load vs. pump cycle) can be used to diagnose and optimize the pump and the well. The same principle is used for PCPs, except a rotational effect has to be taken into account. Of course by using the rest of the operational data that assist with construction and recognition of operational patterns, the PCP diagnostics becomes more exact and efficient for the production engineer.
The work herein presented reveals field tests of the system used to optimize PCP wells, based on the important usage of axial load and several other variables (current, pressures, etc) with a special ingredient that has a tremendous impact in optimization: Artificial Intelligence and Automation. The mathematical principles are also presented to encourage the usage of axial load in a multivariable mathematical model in order to complete a good optimization scheme for these wells. The hardware tools in the well completion needed to perform such a task are discussed as well, including the axial load measuring device.
The benefits of operating a PCP system using a Progressive Cavity Pump Optimization System (PCPOS) are substantial, as described in this paper. The idea is to reduce downtime, workovers, improve system operating response time and equipment useful life, while optimizing the well production.
Integrated Laboratory Field Application for Thermal Recovery Process
Authors: Lopez Elias , Rojas Luis , Mata Tomas , Mendoza Humberto , Briñez Abrahan 
Published: December 2007

Abstract
The Bolívar Coast Heavy Oil Fields (Tía Juana, Lagunillas and Bachaquero), located at the eastern onshore area of Maracaibo Lake, Western Venezuela, contain some 37 billion barrels of Oil Originally In Place. The recovery from these three giant fields is 5.5 billions (15% STOOIP), and is expected to reach 7.7 billions (21% STOOIP) under current primary recovery method (Cyclic Steam Injection).
It has been estimated that an additional 39% of STOOIP in potential areas for steamflooding could be recovered by this process. Previous conceptual studies, and field projects in Bolivar coast area has showed high recovery factor and marginal economics. Those project were conducted under conventional application of technology.
In the last 10 years, technology has evolved in such a way that monitoring can be improved and the performance enhanced for secondary recovery process. These new technologies, such as 4D seismic, Tomography, fiber optic, new approach for steam generation etc., have been tested in different steamflood projects with high impact in the added value.
PDVSA E&P has adopted a new approach to carry out technological projects under the philosophy of the Integrated Field Laboratories. This concept is a wider definition of a Pilot Test, since it encompasses the ideas of evaluating a secondary recovery process and performing the corresponding reservoir management.
The reservoir management includes the evaluation of different technologies for monitoring and control and the simulation and visualization of the process itself, so injected fluid fronts can be tracked down the reservoir. This will allow the creation of an integrated data base and the use of intelligent information systems in order to predict changes and perform decision analysis. The lesson Learned in this Lab will help us to optimize and become marginal projects into profitable ones.
This paper presented the results obtain up to date in the integrated field laboratory that for heavy oil is conducted in W-6 area of Lagunillas Field in the Bolivar coast.
Flow Simulation Study of the Namorado Sandstone (Albacora Field, offshore Brazil) Accounting for Scaling of Petrophysical Properties
Authors: Bonet L. , Romeu R. K. , Barroso A. S. , Sombra C. L. , Cortez M.M. M. , Almeida S. R. , Schwerdesky G. , Mihaguti M. K. , Sarzenski D. 
Published: December 2007

Abstract
This paper describes the reservoir flow simulation study of the Namorado Sandstone, Albacora Field (offshore Brazil). This study is the end point activity – to which the geological description, geostatistical modeling and upscaling results converge – of the project PRAVAP-2, a main project designed to develop technology on reservoir characterization at Petrobras. This paper details work executed by a multidisciplinary team on a flow simulation study performed in a stochastic modeling scenario. We present aspects related to the model construction and the results obtained from the flow simulation study.
The fluid flow model considers a deterministic framework built with high-resolution stratigraphy and detailed structural analysis. Twelve stratigraphic units were grouped in six simulation layers. The heterogeneities inside each layer were modeled using a geostatistical approach: we used the Markov-Bayes simulation method to integrate seismic and well data.
A multi-step upscaling technique was used to generate the effective petrophysical properties for the fluid flow simulation model. The idea is based on (1) a hierarchical description of the reservoir heterogeneities and on (2) the computation of the effective properties bottom-up through this hierarchy. Three main work scales were defined: "porous systems" (microscopic scale); "composite facies" (log and core scale); and "seismic facies" (interwell to field scale). Effective permeabilities and two-phase pseudo-functions were numerically computed for each facies at each scale.
The simulation grid has a corner point geometry, comprising a total of 46,200 gridblocks with areal dimensions of 100m x 100m. The interconnection of layers was modeled by changing the vertical transmissibility distribution.
The history matching was performed by the adjustment of the average pressure for the six layers and of the reservoir production history. The results demonstrated that our sophisticated model allowed a very fast history matching. Extrapolations investigated the adequacy of the development plan, in special the type of the well, horizontal or hydraulic fractured vertical, the number and locations of these development wells to be drilled.
Large Scale Integrated Reservoir Study: The Bachaquero Intercampos Experience
Authors: Lopez D. , Muñoz R. , Gonzalez J. E. , Gou Y. , Pascual J. C. , Cosentino L. 
Published: December 2007

Abstract
A large scale integrated study has been performed in the Bachaquero Intercampos Field, Lake Maracaibo, Venezuela. The project concentrated on the complete revision of the static and dynamic models of the field, with the aim of identifying new reserves and define a new development plan. The dimension of the field and the huge amount of available data required an effort in terms of prioritizing the technological and human resources allocated to each discipline.
The new geological model revealed the presence of a previously untargeted shadow zone below the main reverse fault of the field (subthrust trap). The development plan was focussed on the exploitation of these new reserves and is adding about 10 years of production to the field.
The first phase of the development plan started in early 1998 and so far 3 wells have been drilled and completed. These wells confirmed the new geological model and are currently producing more than 15% of the total field production.
Discounting Rate: A Matter of Common Sense Rather than a Theoretical Problem
Authors: Rosbaco Juan A. 
Published: December 2007

Abstract
Different rates proposed by several authors to discount cashflows of given projects are discussed. The paper starts by reviewing what the objectives of an evaluation are and later presents the different discount rates suggested by the authors. After a theoretical but fundamentally logical analysis it is concluded that there is no universal discount rate that can be used in all situations; to do so would disregard both the fact that an evaluation can have different objectives and that the environment in which projects will be carried out and companies will develop is unique in each case.
Determination and Prediction of Wax Deposition from Kuwaiti Crude Oils
Authors: Elsharkawy Adel M. , Al-Sahhaf Taher A. , Fahim Mohamed A. , Al-Zabbai Wafaa 
Published: December 2007

AbstractCrude oils produced from the formations are transported and processed at low temperatures where solid wax particles may precipitate. These solid particles cause additional pressure drop in production tubing, pipeline, and processing equipment and eventually cause plugging. Great saving in the cost of operating such equipment can be achieved from accurate prediction of wax appearance temperature (WAT) and the amount of wax formed at given conditions.This paper reports measurements of wax content by acetone precipitation techniques as well as measurements of wax appearance temperature (WAT) by viscosity measurements and differential scanning calorimetry (DSC) of eight different stock-tank Kuwaiti crudes. Viscosity measurements indicate that crude oils exhibit Newtonian behavior at temperature above WAT and Non-Newtonian elsewhere. Comparison of WAT measured by DSC and viscosity indicates that the viscosity method overestimates the WAT. Crude oil gravity measured, by digital density meter, and molecular weight, by vapor pressure osmometer, were used to characterize the plus fraction and predict WAT and amount of wax formed at given condition by the thermodynamic model. Comparison between predicted and measured results shows that measured Wax appearance temperature (WAT) by DSC compare very well with that predicted from the model for most crudes. However, Wax contents measured by modified UOP method 46-64 are not in good agreement with that predicted by the thermodynamic model.
Applications of Geomechanics in the Development of the Naturally Fractured Carbonates of the Mara Oeste Field, Venezuela
Authors: Sánchez D. M. A. , Vásquez A. R. , Van Alstine D. , Butterworth J. , García J. , Carmona R. , Poquioma W. , Ramones M. 
Published: December 2007

Abstract
A geomechanical study for naturally fractured carbonates was performed as part of an integrated study for the Mara Oeste field in Venezuela. The study included working with one paleomagnetically-oriented core in which natural and induced fractures were identified and oriented. Geomechanical static and dynamic laboratory tests were performed, to obtain strength, deformability and failure characteristics of the rocks. The in situ stress field orientation was determined in one well by using special core techniques such as ASR, DSA, AAA and SWAA. Regional information provided by focal mechanism data available in the Maracaibo basin was integrated together with image logs for eleven wells. Natural fractures and breakouts were studied and fracture orientation and in situ stresses were related with geological structures present in the field. A stress orientation map was built with all the available directional information. In situ stress magnitude was estimated by lost-circulation data, extended leakoff test and back-analysis from breakouts. A three-dimensional stress model of the field was performed using a lagrangian finite difference code. The model showed that stress orientation is dependent on geometry of the layers, and faulting can introduce jumps in stress magnitude. Out from the influence of the main faults the model reproduced the regional trend of stresses. Close to the main fault of Mara Oeste, stress rotation was evident both in depth and spatially, particularly at the crest of the folds. The model provided estimates of in situ stress magnitude that can be used to design new wells in blocks with little information.
Use of Surfactants in Cyclic Steam Injection in Bachaquero-01 Reservoir
Authors: Valera Cesar A. , Escobar Manuel A. , Iturbe Yrene J. 
Published: December 2007

Abstract
Bachaquero-01 is one of the biggest heavy oil reservoir (11. 5 °API, 23511 acres and 6621 MMBO of OOIP) that possesses Petroleos de Venezuela (PDVSA) western division in Maracaibo Lake Basin.
Cyclic steam injection as a development strategy in Bachaquero-01 began in 1971, and until November 1998 a total of 344 wells have been stimulated with 1006 cycles.
In Bachaquero-01 reservoir verticals wells are completed in one, two, three or four oil producing zones, in a range between 80 and more than 300 feet, as a consequence gravity override and steam channeling are two reasons that reduce the efficiency of production in cyclic steam injection. In order to reduce these mentioned effects, a surfactant of the linear ionic-alkyl-aryl sulfonate type (LAAS) has been used, which generates a stable foam that has as objective to block the most permeable areas and to achieve a uniform injection profile in order to stimulate efficiently those zones with low permeability and recovery. This effect has allowed obtaining between 15 and 40% more production per cycle.
This technology was evaluated in 1997 in the horizontal and reentry wells completed in the main sand of the reservoir, with the purpose of obtaining a uniform profile of injection along the whole horizontal section. The production obtained after the period of soaking indicates a very good stimulation in this type of wells, for that reason its use is being extending in 1998.
This paper presents the results obtained with the stimulation with steam and surfactant carried out to the vertical and horizontal (new and reentry) wells belonging to the Bachaquero-01 reservoir.
Recent Advances in Steamflood Technology
Authors: Hong K. C. 
Published: December 2007

Abstract
Worldwide heavy oil production has undergone phenomenal growth since the first known application of steam in the late 1950s. This growth, especially during the past decade, resulted primarily from technological advances made in the areas of steamflooding that include the process itself, steam generation and distribution, injection and production facilities, and performance prediction. These advances helped increase oil recovery, extend the process application to wider ranges of reservoirs and fluids, and improve the process efficiency (e.g., reduce operating costs). This paper describes some of the more important technological advances made during the past decade.
Fracture Growth and Reorientation in Steam Injection Wells
Authors: Weijers L. , Wright C. A. , Demetrius S. L. , Wang G. , Davis E. J. , Emanuele M. A. , Broussard J. B. , Golich G. M. 
Published: December 2007

Abstract
Conventional wisdom regarding fracture orientation1 of steam fractures is that they grow along the same orientation as "typical" propped fracture treatments – i.e., perpendicular to the least principle stress direction. However, direct measurements (utilizing surface tiltmeter fracture mapping) show that the orientation of steam-induced fractures is very different from propped fractures. Steam fractures have been observed to grow predominantly along two distinct planes that are oriented 45° with respect to the preferred fracture plane. These two planes coincide with the planes of maximum shear stress. Steam fracture reorientation toward these two planes has thus far been directly observed in the South Belridge, Lost Hills, and Cymric Fields in the San Joaquin Valley in California.
The measured data also shows that the fracture orientation is sensitive to the injection rate. Above a "critical" rate (which most likely depends on horizontal stress bias, shear frac conductivity and fluid viscosity) fractures grow perpendicular to the minimum principle stress. Below this critical rate, however, fracture growth is along the two distinct maximum-shear orientations. Steam injection wells are especially vulnerable, as steam injection rates are generally low in comparison to propped fracture treatments. The proposed mechanism for steam fracture reorientation that we present in this paper is pore pressure elevation along a direction of enhanced permeability along shear fractures ahead of the fracture tip, which causes the preferential fracture growth direction to change along the direction of maximum shear stress.
Although fracture reorientation can provide an increase in reservoir access and production rates in areas where the "huff and puff"-technique is used, reorientation is detrimental for steamfloods, as "short-circuiting" may result and reserves may be bypassed.
Softening of Produced Water: Which System is Best for your Application?
Authors: Mommaerts Guy J. 
Published: December 2007

Abstract
Softening of produced water with Ion Exchange Resins has been done for many years. This paper briefly reviews these systems and introduces some new ion exchange systems such as Packed-Bed applied to the softening of produced water. The impact of brine hardness is discussed describing the possible merits of using softened brine. These new techniques have lead to re-evaluating the selection of equipment, especially for water with a TDS of 4000 to 7000 ppm.
Pilot Study Results to Convert Oil Field Produced Water to Drinking Water or Reuse Quality
Authors: Doran Glenn F. , Williams Kimberly L. , Drago Joseph A. , Huang Sunny S. , Leong Lawrence Y.C. 
Published: December 2007

Abstract
The project goal is to convert a currently unusable by-product of oil production, produced water, into a valuable drinking water resource. Results from a 10 gpm pilot study were used for a conceptual design and cost estimate for a 44,000 bpd treatment facility. Generally, the pilot study demonstrated that by altering operating conditions, the treated water could meet industrial, irrigation, and drinking water quality standards. Four scenarios were evaluated, 2 industrial and one each for irrigation and drinking water. The total project cost estimates, with an accuracy of approximately −15 to +30 percent, ranged in capital cost from $3.1 to $12.3 million with an O&M cost ranging from 4.5-23.4 ¢/bbl of water treated.
The Application of Modular Formation Dynamics Tester -MDT* with a Dual Packer Module in Difficult Conditions in Indonesia
Authors: MP Siswantoro , Indra T. B. , Prasetyo I. A. 
Published: December 2007

Abstract
Since the introduction of the wireline formation tester in 1955, these tools have provided the oil and gas industry with measurements for the determination of formation pressure, fluids in-situ as well as giving formation fluid samples for identification and analysis.
Pressure and fluid samples are obtained by setting a rubber packer and small diameter probe. The packer hydraulically isolates a small part of the formation from the hydrostatic pressure, while the probe enables communication between the tool and formation. This conventional technique is well suited for thick and permeable clastic formations. However, for difficult conditions such as fractured limestone, thin and laminated formations or formations with very low permeability, the application of a single probe technique is limited. Under these conditions, the small packer may not be able to isolate the zone, may miss a thin zone or in a formation with very low permeability, the contact area with the packer may be too small to let the fluid flow. To identify formation fluids under any of these conditions, a cased hole DST was usually run, but this is time consuming and costly.
To help overcome this, a new technique has been developed using the MDT* with a dual packer module. Within Indonesia, this technique has been applied successfully to a fractured carbonate reservoir, a thinly-bedded reservoir and a formation with very low permeability. This wireline conveyed straddle packer has the capability of hydraulically isolating a minimum of one meter of formation. The dual packer can be set repeatedly at different locations on a single trip in the well. Using these, pressures, real-time formation fluid identification, PVT samples, permeability and flow rate estimations can all be evaluated in detail. Electrical borehole images (FMI*) have been incorporated into this technique to locate fractures and laminations in order to improve the choice of test point.
This paper describes the practical use of this technique in these types of very difficult formations that occur within Indonesia and demonstrates the benefits of this new technology.
Selection of Metallurgy and Elastomers Used in Completion Products to Achieve Predicted Product Integrity for the HP/HT Oil and Gas Fields of Indonesia
Authors: Williford James , Rice Pat , Ray Thomas 
Published: December 2007

Abstract
In the Indonesian Archipelago oil-and-gas fields, high pressure/high temperature (HP/HT) sour-service applications are becoming more prevalent as new areas are being explored and defined. In order to select the appropriate metallurgy and elastomers for completion products in these corrosive environments, careful consideration must be given to the well environment. Therefore, thorough review of well data is required so that completion cost efficiency can be realized, and product integrity can be maintained. This paper will present a selection process that can be used to identify the most appropriate metallurgy and elastomers for various wellbore environments, and in the case histories presented here, was beneficial in selecting the completion components for the HP/HT applications in these fields.