bluuebunny/crossref_metadata_2025_split huggingface dataset:
Field Experience And Concept To Be Taken Into Account In A Fpso Design
Authors: Mastrangelo C.F. , Castro A.N.M. 
Published: December 2007

Abstract.
This paper contains the main points which need to be addressed in the design of an FPSO, based on PETROBRAS's 13 years of experience in operating this type of production unit.
It is possible to analyze the experience as well as the problems that have occurred in previous tower-yoke and calm-yoke systems, to find good ideas and solutions for turret based systems.
During the design of FPSOs, designer must consider not only the most severe environmental conditions, but also the less severe conditions during which the Process Plant and other equipment, like turret swivels, will normally be used. We stress that less severe environmental conditions can be the determinant factor under which it will be dimensioned. The combined experience of the Naval and Offshore Industries, has assisted in the development of new concepts, related to FPSO conversion and new build constructions presently underway for PETROBRAS Future design will be aimed at producing oil and gas from fields located in deeper and deeper water depths.

Introduction and Background.
Stationary offshore terminal facilities utilizing Crude Oil Tanker Ships were employed by Oil Industry as early as fifty five years ago. At first, a tanker was simply connected to a single point mooring (Calm) by conventional hawsers where it was used as a combination buffer storage vessel and mooring platform shuttle tanker. A further step in the evolution of this type of unit came about in Brazil in 1975, when the installation of process facilities over a tanker ship main deck was developed.
This system began operating in February of 1979. The first concept was the TOWER-YOKE, then it changed to a CALM System, CALM-YOKE and nowadays TURRET System. Some reason for these changes, including adaptations necessary for the specific purpose of each project will be described.
In Brazil there are 6 FPSOs under construction and another 4 under conceptual and basic design. Experience gained from operating this type of unit has been useful when determining technical specifications and life expectancy design for future conversions.
FPSO technical team members are selected from both the Naval and Offshore Industries. This helps to create new concepts, enhanced design, and increased reliability.
The following phases of this first FPSO will be analyzed:
TOWER-YOKE.
CALM
CALM-YOKE

TURRET
Advantages of each one and problems occurred.
P. P.^ Moraes History.
All systems used the same tanker ship. The tanker Presidente Prudente de Moraes that was built in 1959 as a 33,000dwt crude oil tanker. She was Jumborized in 1974 to 52,000dwt. In 1979 the ship was converted into a FPSO with a 60,000bpd process plant capacity.
Main Characteristics of the vessel:
Length: 231.10m
Breadth: 26.00m
Depth: 16.87m
P. 699^
Novel Approaches to Profile Modification in Horizontal Slotted Liners at Prudhoe Bay, Alaska
Authors: Bond A. J. , Blount C. G. , Davies S. N. , Keese R. F. , Lai Q. J. , Loveland K. R. 
Published: December 2007

Abstract
The development of new techniques and materials for performing profile modification treatments in horizontal, uncemented slotted liner completions at Prudhoe Bay, Alaska is reported in this paper.
Historically, it has been difficult, if not impossible, to perform remedial profile modification treatments in horizontal slotted liners. The lack of annular isolation and uncertainties with conventional fluid placement posed seemingly insurmountable challenges. The development and field trials of two new techniques that address these problems are presented in this paper. The first approach uses advanced gel technology for fullbore, non-selective treatments for water shut off and selective placement for gas shut off. The second uses a new thixotropic cement slurry to place a chemical packer around the slotted liner for zonal isolation - opening the door for conformance treatments. Certain preliminary successes of these techniques have prevented the need for sidetracking wells to new locations or permanently abandoning zones. This has saved the operating companies significant wellwork expenditures.
Treatments have been performed on five wells to date with several more in the development stage. Treatment descriptions, operational rationale, and pre- and post-production trends are presented.
The horizontal slotted liner profile modifications performed are all technical successes with 60% of the treatments also economically viable. Even though it is early in the life cycle of these technologies, the successful treatments are encouraging and have opened up a large candidate pool. These new techniques and materials are promising options allowing remedial work in horizontal wells with uncemented slotted liners.
Successful Water Shutoff in a High-Temperature, High-Volume Producer - A Case History from the Ula Field, Offshore Norway
Authors: Bergem J. , Fulleylove R.J. , Morgan J.C. , Stevens D.G. , Dahl J.A. , Eoff L.S. , Enkababian P.G. 
Published: December 2007

Abstract
This paper presents field data from the successful use of an in-situ polymerisation water shutoff system in a hot (147 C), high productivity, high rate, well. Previously the chemical system had not been applied above 93 C or in such a prolific well. The job was performed by a team comprising the operator and two service companies. One service company supplied the selected chemical technology. The other service company supplied the means to deploy the system with the control of placement the job demanded. The success of the treatment resulted from a combination of factors. The job design ensured that oil production from the well would not be harmed even though complete mechanical isolation of the oil-producing zone within the wellbore could not be guaranteed. To ensure the oil-producing zone was not damaged, coiled tubing and packer placement was combined with dual injection to protect the oil. Wellbore and reservoir modelling of the pre-cool and gelant injection was used to estimate the required injection rates and volumes. Laboratory studies used field materials, and field conditions were used to check blocking times and possible problems. The pre-cool design was checked and enhanced by a pre-job injection trial.
Monitoring temperature and the pressure above and below the packer during the actual job allowed highly controlled "live" amendments to the injection regime.

Introduction
The Ula field lies in Block 7/12 of the Norwegian Sector of the North Sea (see Figure 1).
P. 843^
Evaluation of a Water Conformance Treatment in Prudhoe Bay Alaska
Authors: Chan K.S. , Bond A.J. , Keese R.F. , Lai Q.J. 
Published: December 2007

The new Water Control Diagnostic Plots technique was found to be very effective for evaluation of a water conformance treatment conducted in Prudhoe Bay last year.
It determined the channeling as the main mechanism for poor conformance as seen in the diagnostic plots of offset production wells. Log-log plots of Water/Oil ratio vs time exhibited a characteristic behavior of channeling behavior. Post treatment well production history data of the offset production wells were plotted and compared with the pretreatment diagnostic plots. Change in slope or trend in Water/Oil ratio curves as used as a good indicator of successful problem correction and good treatments.

Introduction
The thick Prudhoe Bay Sadlerochit sandstone formation, which is at a vertical depth of 8,800 ft' is bounded by a gas cap and a bottom water aquifer. Portions of the field have been under waterflood since 1980. The field is producing approximately 0.9 MM BPD oil, 1.5 MM BPD water and 7 MMM SCFPD gas. As reservoir depletion continues, water and gas production rates continue to increase.
Most of the produced water and gas are re-injected. The majority of gas is re-injected into the gas cap. Some is made into miscible injectant for a tertiary recovery process. The water is treated and filtered and incorporated into the ongoing waterflood program. However, the capabilities of water and gas handling surface facilities are limited even after recently completing a series of plant expansion projects. Increasing water and gas production drives up water and gas handling costs and decreases oil production. As reservoir depletion continues, gas cap and enriched gas as well as waterflood water breakthrough occurs frequently at the producing wells. The Gas/Oil and Water/Oil contacts get closer and closer to the perforated intervals. The potential of bottom water and gas cap gas coning and channeling increases. The gas and water produced by these adverse mechanisms by-pass reserves and impede normal production.

The Diagnostic Plots
A new diagnostic plot technique has been developed to differentiate between mechanisms of excess water and gas production. The production data are used to plot in log-log the WOR, GOR or WGR (Water/Oil, Gas/Oil and Water/Gas Ratios respectively) and their derivatives versus time. Together with the completion and workover history, the excess water and gas production mechanism can be determined.
Figure 1 shows a comparison of WOR behavior for normal layered reservoir depletion and bottom water coning. This technique can be applied to oil or gas wells, vertical or horizontal wells. Figure 2 shows a case of rapid water entry occurring in a horizontal well. The drastic increase in WOR and its derivative indicate such a change after approximately 300 days. The mechanism is a near wellbore or cement channel problem.
P. 853^
Integrated Reservoir Management via Full Field Modeling, Pt. McIntyre Field, Alaska
Authors: Hagedorn K. D. , Coleman D. R. , Frank K. J. , Janes R. W. , Pospisil G. 
Published: December 2007

Abstract
Development drilling, depletion planning, and waterflood management have been guided by the use of a finely gridded full field reservoir simulation model (FFM) since startup of the Pt. McIntyre field in October 1993. A detailed geologic model formed the basis for development of the reservoir simulation model. A multicompany, multidisciplinary team used 3D seismic interpretation and data from over 7000 feet of core to provide the foundation for this geologic model. The full field model constructed from this geologic framework yields an excellent match to field history, including individual well matches, with very little "history matching" required. The model has been used to address a wide range of reservoir management issues in addition to providing conventional long-term reservoir performance forecasts. Development and infill drilling assessments, facility expansion evaluations, and individual well work forecasts have been based on FFM results. More novel applications of the model include waterflood optimization and hydrocarbon miscible EOR evaluation. The FFM has been the focal point for integrating geologic, petrophysical, reservoir surveillance, and surface facilities information to improve reservoir management decision making at Pt. McIntyre.
Matching the Ancient Filling of an Oil Accumulation to Improve the Reservoir Characterization
Authors: Filho J. D. Souto , Corrêa A. C. F. 
Published: December 2007

Abstract
A series of simulation runs are conducted to study the impact of reservoir heterogeneity and external geometry of the accumulation on oil distribution in the subsurface. The geologic model selected to this study was the Alto do Rodriges oil field, located in the onshore portion of Potiguar Basin (RN- Brazil). The fluid flow modeling is performed with a three-phase flow, three-dimensional commercial numerical simulator. The objectives of the study are:
- to investigate the effects of the internal heterogeneity (permeability barriers) in the ancient filling of a petroleum accumulation by using a vertically refined cross-sectional simulation model;
- to quantify the time required for hydrocarbon entrapment in the accumulation (geologic time); and
- to examine the factors that can affect the production mechanisms of the reservoir.
The methodology presented in this paper can be used to provide a better understanding of the mechanisms that control the fluid distribution in the reservoir. This method can also be used as a support for reservoir management, providing important contribution for the exploitation plan, including the dimensioning of improved oil recovery projects.

Introduction
An oil field is the result of a complex fluid movement in the subsurface. Its existence is directly related to the equilibrium conditions (static or dynamic) prevailing among the capillary, viscous and gravity forces acting in the reservoirs. Cap-rock properties, such as permeability and capillary entry pressure, play also an important role in the reservoir existence.
Due to the particularities of the hydrocarbon accumulations, consisting of a porous system saturated with fluids (water, oil and gas), it is important to understand the mechanisms responsible for its formation so that, from this knowledge, we can maximize the recovery factors of the producing zones. Numerical simulation is a fundamental tool for reservoir management, aiming to define the best conditions for exploitation of a given reservoir (or producing zone). Its application requires the selection of a physical model, which shall represent as accurately as possible the hydrocarbon accumulation to be exploited.
This work describes the application of the numerical simulation to a stage prior to the establishment of an exploitation philosophy for the field, that is, in the stage of elaboration of the geologic model of the accumulation.
The proposed working model objects to investigate the fluid distribution in the subsurface by considering its flow into the reservoir unit. This approach would allow us to raise, still in the beginning of the field productive life, the problems related to positions of fluid contacts, the influence of permeability barriers on the fluids distribution in the reservoir, and the definition of horizons in which the hydrocarbon flow is made easier.
Evaluation of Treatments for Control of fines Migration in the Ceuta Field in Venezuela
Authors: Colmenares F. J. , Padron A. , Boggio C. , Montoya F. 
Published: December 2007

Abstract
In the Ceuta field, an area located in Lake Maracaibo and assigned to Maraven, S.A. (a subsidiary of PDVSA) for exploitation, there has been a significant production decline during the producing life of wells. Production has dropped from 2000 BOPD to 50 BOPD in 10 months. HCl and HF stimulations have not been successful in restoring the lost potential.
Flow tests and the mineralogical analysis of cores from the area have shown that there is a very high content of fine clastic material, which has a very special characteristic: it moves through pores. When this material finds very small pore spaces, then it plugs them, which results in reduction of formation permeability.
In order to be able to control this problem and restore the permeability of the damaged formation, matrix treatments with Fluoboric Acid (HBF4) have been applied in several wells located in the Ceuta field. These treatments have made it possible to stabilize the clastic material. After the treatment, well production has remained stable for more than four years, and the average gain has been 1500 BOPD/well.
This paper is about the experiences and results obtained during a pilot test involving 5 wells.

Introduction
The Ceuta field is located in the southeastern area of Lake Maracaibo. Its production potential is around 70.0 MBOPD of net oil (37 API). This production potential comes from reservoirs belonging to the Misoa formation from the Upper and Lower Eocene B and C. This potential has been impaired by formation damage which, as proven, is due to fine migration.
Flow tests and the mineralogical analysis of some cores from the area have shown that there is a high content of clay particles such as kaolinite and "Mixed Layer" illite, which have a very special characteristic: they move through pores. When this material finds very small pore spaces, it plugs them, which results in the reduction of permeability in the medium.
In order to control this problem and restore the permeability of the damaged formation, matrix treatments with fluoboric acid have been applied in several wells located in the Ceuta field. These treatments have made it possible to stabilize these migratory clays, and production has remained stable for much longer, as compared with the results obtained when the traditional formulation was applied (12% HCl + 3% HF).
The purpose of this report is to share Maraven's experience involving the matrix treatment of formations having this fine migration problem.
Optimized Field Matrix Acid Stimulation Parameters in a Multi-Layered Reservoir Using Foam Diversion
Authors: Talabani S. , Hareland G. , Rajtar J. M. , Islam R. 
Published: December 2007

Abstract
Matrix acidizing stimulation treatment in a multi-layered reservoir may achieve a limited success because of poor acid diversion to layers of lower permeability. A foam is currently used to temporarily plug higher permeability layers, and divert more acid to the damaged layers.
A combination of new factors that optimize the foam design parameters were assembled into a simple equation. The equation is based on laboratory experiments conducted on Berea sandstone cores under low (100 psi) and high (3000 psi) average pressures. According to this equation the degree of acid diversion into the damaged, lower permeability layers in the field can be specified and controlled.
A few parameters control the success of the foaming-acidizing process., hence there are a few input parameters to the equation. During a field acidizing job, the optimum combination of these parameters can be found from the calculation of the Average Optimized Diversion Factor (AODF). The AODF indicates how successfully the acid is diverted to the lower permeabilitylayers during the foam and acid injections. Results from the laboratory experiments show that the Average Optimized Diversion Factor (AODF) indicates instantly, from the inlet pressure and the change in acid injection rate, if the damaged zone will be successfully stimulated.
In field applications, fast calculations of the AODF can predict the effective removal of the damaged zones with time, using the change in the acid injection rate, bottom hole inlet pressure, and the volume of the acid injected as input parameters. Increase of the AODF indicates that the removal of the damaged zone is progressing in the right direction.
PROKICK - an Integrated Software for Supporting Deepwater Well Control Operations
Authors: Sotomayor Gabriel P.G. , Santos Otto L.A. 
Published: December 2007

Abstract
This paper presents the development and application of a computational tool that emphasizes the integration process in the several phases of the well control operation. This tool, named PROKICK, provides the drilling personnel with information and several computational resources covering many aspects related to well control in deepwater drilling. The paper discusses relevant points of the software development, shows important features offered by the system and presents a typical deepwater well control case to illustrate the application of the software. The system can also be used as a very powerful instructional tool for training and certification programs in well control.

Introduction
Well control issues in very deepwater drilling are more complex and comprehensive due to specific problems found in such environments. Low fracture gradients, lengthy choke and kill lines, hydrate formation and gas inside the marine riser are some of these problems that call for more complex well control procedures and practices, sophisticated well control equipment and a very well qualified drilling crew. Thus, this complexity demands fast access to a huge amount of information previously stored or generated during kick incidents to warrant quick and adequate actions.
In this scenario, the utilization of integrated computer systems is a key component of the entire well control process. Available systems, however, are not specifically designed for very deepwater well control applications. Thus, a study was commissioned in Brazil to develop a well control integrated system that incorporates the Brazilian experience in drilling safety in very deepwater environments.
The software includes three modules:
- well design from well control standpoint and kick prevention that also includes information concerning well control equipment and rig crew training and certification;
- rig crew drills, kick detection and well closure; and
- killsheet and kick circulation out of the well.
The software package includes two expert systems (one dealing with anomalies during normal drilling operations that includes kick events and the other with diagnosis and correction of operational problems during the kick circulation) and a kick simulator for predicting wellbore pressure during the kick removal process. The utilization of the software is illustrated through a very detailed example of a kick situation in a typical Brazilian deepwater well.
Laboratory Tests for Wellbore Stability in Deepwater, Brazil
Authors: Santos H. , da Fontoura S. A. B. , Gupta A. , Roegiers J.-C. 
Published: December 2007

Abstract
Wellbore instability problems in some wells located in the deepwater portion of the Campos Basin presented a serious challenge to the economical development of the huge oil reserves already discovered. Identifying the real causes of the instability was essential to better design the wells. This paper describes the comprehensive laboratory test study for wellbore stability purpose conducted on preserved downhole shale cores. The paper presents the rationale for the tests, the most important results, and also the new tests developed to better investigate the reactions and characterize the rocks. The results show, as opposed to the initial hypothesis, the problem was mainly due to mechanical failure, rather than due to a chemical interaction between the rock and drilling fluid. This broad investigation has allowed a better understanding of the interaction mechanisms between the shale and the drilling fluid, indicating the need to reevaluate some of the existing concepts and procedures.
The Methodology of Decision Making in Global Problems of Russian Gas Industry Development
Authors: Sukharev M. G. , Stavrovsky E. R. 
Published: December 2007

Abstract
One of the most serious problems in planning of the development of large and old gas-supplying systems consists in optimal choice between several projects, when many technological, economical and other aspects are to be considered. The report presents a new methodology of multicriterial estimation and comparison of such projects which was applied to one of regional gas-supplying systems in Russia.