bluuebunny/crossref_metadata_2025_split huggingface dataset:
Refloating Maureen Oil Platform (110,000 Tonnes) for Re-use in Waters Away From the North Sea
Authors: Tilling Geoff 
Published: December 2007

ABSTRACT
The Maureen Oil Platform located in Block 16/29 of the UK continental shelf, North Sea has been in operation since September, 1983.
The fields that the platform serves are now nearing the end of economic production life and the operator, Phillips Petroleum Company United Kingdom Limited and its coventurers now have to decide how to most effectively abandon and dispose of the facility.
The platform is a three tank steel gravity structure. Each of the three "legs" is a cylindrical steel oil storage tank which sits on the seabed.
The platform utility and process plant is installed on the main deck, the lower deck and on a mezzanine level. There are five decks of accommodation and office modules sited on the main deck.
The three cylindrical storage tanks are normally fully flooded with water, crude oil or a combination of both, depending on the frequency of export to the offtake tanker. The tops of the storage tanks are at an elevation of 74 m above the seabed.
The platform is unique in its design, being the only steel gravity based structure in the North Sea.
The depth of water in which the platform stands is 95.6 m at L.A.T.
The platform was floated into location, already complete, and ballasted into position. In order to meet disposal regulation and international law its most likely removal will start with the entire platform being refloated.
As a free floating mobile platform it is available for use in any other waters of the world, subject to environmental and soil conditions.
This paper will demonstrate the work that has been carried out (and is continuing) to verify the refloat and marine stability of the platform as a vessel under tow. As an alternative, methods for transporting topsides and gravity structure separately followed by remating will also be discussed.
The paper will explain the platforms' processing capabilities, its flexibility as a work base and its excellent maintenance condition.
Study and Application of Positive Sol Drilling Fluid
Authors: Chun-guang Zhang , Wan-guo Hou , Dejun Sun , Tong-tai Xu 
Published: December 2007

ABSTRACT
This paper reports a new drilling fluid system--positive sol drilling fluid (PSDF). The electrokinetic behaviour, rheological properties and the ability to inhibite clay swelling of positive sol (PS) and PSDF were studied. It was found that PSDF might form weak negative system and positive system under different conditions, and the gel strength and rheological parameters of PSDF could also be adjusted to meet drilling technology demands by changing the ratio of clay-sol. Both PS and PSDF demonstrate high inhibition ability, and PSDF can be treated with conventional additives. In this paper, the field test results of PSDF are introduced as well.
Field-Wide Compositional Simulation for HPHT Gas Condensate Reservoirs Using an Adaptive Implicit Method
Authors: Hsu H. H. , Ponting D. K. , Wood L. 
Published: December 2007

ABSTRACT
The recovery mechanisms of high pressure and high temperature (HPHT) gas condensate reservoirs consist of pressure depletion, water encroachment, rock compaction and condensate banking near a well bore. The last two mechanisms require special treatments in a reservoir simulation model: the rock compaction leads to permeability reduction with declining pressure while the condensate banking requires small grids around a well. The condensate banking, which affects well productivity, was successfully simulated with a compositional simulator using radial local grid refinement within a Cartesian global grid system. A benchmark study was conducted to ensure the correctness of the local grid refinement.
An adaptive implicit method (AIM) was implemented which solves the local and global grids simultaneously. However, by making the local grids implicit, one avoided the time step restrictions which would otherwise occur due to their high throughput rates. In solving the linear equations which arose from the coupled local-global system, the grid ordering was found to be important. The optimal ordering proved to be that in which the local grids were placed before the global. This technique resulted in reduced computing time as well as robustness in dealing with field size models.
The solution technique was applied to a HPHT gas condensate prospect in the Central Graben region of the North Sea. This paper will address the recovery mechanisms regarding the rock compaction and the condensate banking. In addition, it will discuss the simulation of hydraulic fracturing as a means of improved recovery. Finally, it will present some experimental data that form the basis for input to the simulation model.
Scale Prediction and Prevention Technologies in Low-Permeability Reservoir During Waterflood
Authors: zhu Yiwu , zhao Zuozi , Ju quanyi , Wu Ping cang 
Published: December 2007

ABSTRACT
Scale could be formed in Waterflood formation during the water injection development owing to the water incompatibihty and the variations of thermodynamic conditions and etc. This paper presents a computer model for predicting the sulfate scaling tendency along with the study of chemical control actions and technologies of reservoir scaling. Results of the technologies are evaluated according to applications in the field.
The Flow of North Slope Crude Oil and Its Emulsions at Low Temperatures
Authors: Rose S.C. , Marsden S.S. 
Published: December 2007

Abstract
This paper describes work that was carried out to determine the nature of low temperature flow through pipes of Prudhoe Bay crude oil and its emulsions with synthetic brine. These fluids were prepared and pumped both at temperatures ranging from 10 degrees to 30 degrees F and also at room temperature through a flow system consisting of a reservoir, a pump, a copper tube heat exchanger, a tubular flow resistance, and a return line to the reservoir. The heat exchanger and the flow resistance were immersed in a constant temperature bath (water and methanol) that could be adjusted to various temperatures. The pressure drop across the resistance and the viscosity of the fluids were observed and recorded.
The variation of viscosity with temperature and with emulsion quality (ratio of oil volume to total volume) was studied. A significant lowering of the apparent viscosity and of the pressure drop through the flow resistance was pressure drop through the flow resistance was found using emulsions as compared to the crude oil. Pumping an oil-in-water emulsion ma significant advantages in a Trans-Alaskan pipeline. pipeline
Introduction
The flow of emulsions in pipelines has received little attention in the petroleum industry. In particular, no work appears to have been done on the subject of emulsions flowing at low temperatures. Nevertheless, the subject may have considerable impact on the industry in light of the recent discoveries of very large oil deposits on the North Slope of Alaska.
An emulsion has been defined as "….. a heterogeneous system consisting of at least one immiscible liquid intimately dispersed in another in the form of droplets." An emulsion has two phases, the continuous and the dispersed. An phases, the continuous and the dispersed. An oil-in-water emulsion (O/W) has water as the continuous phase and a water-in-oil emulsion (W/O) has oil as the continuous phase. The experiments described in this paper deal with both types although the primary emphasis was on the oil-in-water emulsions.
Most studies of the rheology of emulsions have been done at or above room temperature. The only actual work done at low temperatures was concerned with the effect on the stability of emulsions through a freezing and then a thawing process.
The effects of various parameters on the viscosity of emulsions have been studied extensively, although not at low temperatures.
Bilinear Flow Regime Occurring in Horizontal Wells and Other Geological Models
Authors: Du Kuifu , Stewart George 
Published: December 2007

ABSTRACT
This paper mainly describes how the bilinear flow regime can occur in various geological situations including a horizontal well in a dual porosity reservoir, a vertical well in leaky channels or near a high conductivity fault. A particular emphasis is put on illustrating the occurrence of the bilinear flow nature at intermediate time dual porosity response of horizontal wells.
Geological Modelling of a Structurally Complex Reservoir
Authors: Puliti Alessandro , Erba Mario , El-Ageli Ibrahim 
Published: December 2007

ABSTRACT
This paper presents the technical problems faced and the solutions found in the construction of a suitable static model of Bu Attifel field.
The re-interpretation of the seismic volume, the construction of a detailed sedimentological model and the accurate correlations within the reservoir allowed the identification of several tectonic phases and, particularly, the intra-Nubian tectonics affecting only the lower levels of the reservoir.
The conclusions of the geological study led to the identification of a very complex structural model due to the number, slope and, often, synsedimentary characteristics of the faults crossing the reservoir.
During simulation, it was not possible to apply the usual simplifications to the structural model since a dynamic model able to optimise future infill well locations and enhanced oil recovery processes was required.
It was then decided to build a simulation grid reconstructing both fault trend on the horizontal plane and their slope as accurately as possible.
To this purpose, a specific methodology was followed. It consisted of two main phases: the generation of a conventional model with vertical faults and the conversion into a model containing sloping faults.
The final result was the construction of a geological model and a simulation grid representing the structural complexity of the reservoir.
The Construction And Application of Stochastic Models in Early Evaluation Phase of Oil Reservoirs
Authors: Wen Jian , Qiu Yi-Nan , Liu Ming-Xing , Xiao Jing-Xiu 
Published: December 2007

ABSTRACT
In recent years, stochastic modeling technique has become a hot topic in reservoir characterization. Wherease, what should be made clear, if the technique is used in constructing geological models in early evaluationphase, is what problems in oil-gas development study can be solved by this technique. In this paper, focusing on the early evaluation phase of reservoir, the application cases from two reservoirs are used to discuss what practical problems can be solved by sectional reservoir models, which were built up by means of this technique.
Reservoir Characterization Using Model Based Seismic Lithology Inversion – Xijiang 24-3 Field, Pearl River Mouth Basin, Offshore PRC
Authors: Sharrah K. L. , Brumbaugh D. L. , Neff D. B. , Lun Ye Xiao 
Published: December 2007

ABSTRACT
Mapping of sand thickness and porosity was enhanced in the Xijiang 24-3 Field by incorporating the results of a model based seismic lithology inversion process. The method successfully predicted an area of anomalous high porosity*thickness in a pay sand. The porosity data volumes generated by the method are being used in the 3D reservoir simulation for the field.
Corrosion Protection Of Oil Gas Seawater Submarine Pipeline For Bohai Offshore Oil Field
Authors: Chengde Zhu 
Published: December 2007

ABSTRACT
The submarine pipelines for transporting oil, matural gas, seawater is a permanent project with giant investment. This project has been required to protect more than twenty years under the condition without maintenance. But in marine environment with harsh corrosion, we must anticorrode very well to it for safe service above twenty years.
Accoding to a long—term development practice for oil and gas in Bohai Offshore Oil Fields, this article synthetically describes internal and external corrosion control method of various types of submarine pipeline for traspporting oil, gas and seawater, mainly discusses the characteristic, fabrication, construction technical requirement and quality contral requirement for external corrosion coating, riser coating and joint coating for oil, gas and seawater pipelines, also discusses interrelated technical problems for design of cathodic protection system, fabrication, installation, inspection of sacrificial anodes when using Aluminium—Zinc— Indium system anode carries out cathodic protection of submare pipeline, as well as the suing method to prevent internal corrosion of pipeline from corrosive medium in oil, gas and seawater. At the same, the paper also shows adopted national rule and standards in anticorrosion design, fabrication, installation of submarine pipelines.
Wax Deposition Measurement and Scale-Up Modeling for Waxy Live Crudes under Turbulent Flow Conditions
Authors: Hsu J. J. C. , Brubaker J. P. 
Published: December 2007

ABSTRACT
A wax deposition scale-up model has been developed to scale-up laboratory wax deposition results for waxy crude production lines. The wax deposition model allows users to predict wax deposition profile along a cold pipeline and predict potential wax problems and pigging frequency. Consideration of the flow turbulence effect significantly increases prediction accuracy. Accurate wax deposition prediction should save capital and operation investments for waxy crude production systems.
Many wax deposition models only apply a molecular diffusion mechanism in modeling and neglect shear effect. However, the flow turbulence effect has significant impact on wax deposition and can not be neglected in wax deposition modeling. Wax deposition scale-up parameters including shear rate, shear stress, and Reynolds number have been studied. None of these parameters can be used as a scaler. Critical wax tension concept has been proposed as a scaler. A technique to scale up shear effect and then wax deposition is described. For a given oil and oil temperature, the laboratory wax deposition data can be scaled up by heat flux and flow velocity. The scale-up techniques could be applied to multiphase flow conditions.
Examples are presented in this paper to describe profiles of wax deposition and effective inside diameter along North Sea and West Africa subsea pipelines. The difference of wax deposition profiles from stock tank oil and live oil is also presented.
Design and Performance of Chuchupa 14 - First Horizontal Gas Well, Offshore Colombia
Authors: Huang W.S. Bill , French Mike R. , Markitell Barry N. 
Published: December 2007

Abstract
In November 1992, a 2000-ft horizontal well was drilled in the Chuchupa Field, offshore Colombia. Chuchupa is a major gas field in Colombia, contributing about 90% of the gas supply for electricity generation on the northern coast of Colombia. This paper documents the selection, planning, reservoir simulation, drilling, completion and operation phases of this project. The horizontal well, Chuchupa 14, was successfully drilled from an offshore platform in 200 ft of water with a total horizontal displacement of 2000 ft. The entry point of the horizontal well is 6300 ft away from the platform. The formation is a semi-consolidated Chuchupa sandstone at a depth of 5325 ft sub sea, with average thickness of 167 ft, and average permeability of 209 md. Initial production test indicated that the well could be produced at 60 MMSCF/day on a 44/64" choke. This production rate is 4 to 6 times that of a conventional vertical well. Currently, the well is being produced from 40 to 60 MMSCF/day. In this application, the horizontal well can replace at least four vertical wells. With the development of horizontal wells, a significant amount of savings can be realized with fewer platforms and wells needed to develop the remainder of the field.

INTRODUCTION
The natural gas in the northern coast of Colombia is primarily supplied by two gas fields jointly operated by the Texas Petroleum Company and Ecopetrol. The Ballena Gas Field and the Chuchupa Gas Field in the Guajira area, shown in Figure 1, provided more than 90% of the gas supply for electricity generation in the coastal area. While the Ballena Field is partially onshore, the Chuchupa Field is about 7 miles offshore. The original gas in place for Ballena and Chuchupa are 1.5 and 4.2 TCF, respectively. Gas recovery in both fields is 30% and less than 30%, for Ballena and Chuchupa, respectively.
According to a previous reservoir simulation study, some of the existing wells in the Chuchupa Field may face water breakthrough in a near future, therefore replacement wells are needed to insure a continuous supply of gas from this field. Horizontal wells are one of the option to be considered.

BACKGROUND
Figure 2 shows the isopach map of the Chuchupa Field with its discovery well Chuchupa 1 near the center of the field and the 8 vertical producers drilled from the platform. When the field was first placed on production in October 1979, the rate was at about 100 MMSCF/day. As of December 1991, 450 BCF of gas had been produced from the field with the average production rate of 104 MMSCF/day or 13 MMSCF/day/well for the 12 year period. Before the horizontal well was drilled, production from the eight vertical wells was 140 MMSCF/day.
World Record Drain Hole Revives Production from a Barren HP-HT Well
Authors: Uboldi V. , Schenato A. , Fratus A. 
Published: December 2007

ABSTRACT
Willingness to revive production from a High Pressure-High Temperature (HP-HT) well, characterized by poor productivity performance, led to the project of drilling a reentry horizontal drain hole at 5, 500 m TVD. The initial well, drilled and completed in early 1993, hit the target in an area of unusually poor petrophysical characteristics, where the fractures of the dolomitic reservoir were found to be filled with sedimentary dikes.
As a consequence, the well productivity performance was remarkably lower than expected, and the well was soon shut-in.
The well, named Trecate 14, was drilled in the Trecate-Villafortuna field (the biggest and deepest onshore producing oil field in Europe, located in the north-west part of Italy) at 6, 241 m TVD. Wells in this field feature production rates of about 4, 000 bopd, with flowing well head pressures of 400 bar (5, 700 psi) and temperatures of 120°C. The original reservoir pressure is over 1, 000 bar (14, 500 psi) and temperature as high as 170°C–180°C.
Studies undertaken by Geologists and Reservoir Engineers show that an area with suitable petrophysical characteristics could exist nearby the actual bottom hole location, some 150–300 m away.
A technical and economical proposal to recover this multimillion well to profitable production was submitted and approved by Company's Management.
In order to ensure maximum success, as well as achieving a certain offset from the initial wellbore, a certain horizontal displacement was required to increase chances of crossing good producing fractures. Following the 7" casing window milled at 5, 489 m, the drain hole was drilled to 5734 m measured depth; 64 m were drilled horizontally. Drilling was stopped due to repeated heavy mud losses which, on the one hand almost prevented the drilling operations being continued in a safe manner, while on the other hand indicated that potentially good producing fractures were crossed.
The successful conclusion of this project demonstrated the feasibility of ultra-deep drain holes under limited conditions such as those mentioned.
Furthermore, it demonstrated that it is feasible to use currently available technology with only minor modifications, provided that suitable procedures and contingency plans are implemented in advance.
The well was completed introducing modifications in the standard completion design used for other wells in the field. At present, the well is the best field producer.
The Viscoelastic Behavior of HPAM Solutions in Porous Media and It's Effects on Displacement Efficiency
Authors: Xian-Qing Han , Wang Wei-Ying , Xu Ying 
Published: December 2007

ABSTRACT
The viscoelastic behavior of HPAM solutions and its effects on oil recovery were studied by means of core flowing tests and mathematical modelling. The mechanism of improving displacement efficiency due to viscoelastic effects was explained. This paper first presents a method to determine the first critical velocity (or critical viscoelastic velocity), Vce, at which the straining flow occurs. The experimental results indicated that the Vce increases with increasing permeability of porous media. Vce less than 1 m/d was observed.
There is a second critical velocity (or critical transit velocity), Vcr, at which the rheological behavior of HPAM solution transits from pseudoplastic to dilatant behavior. Vcr can be also determined through experiments. Vcr ranges from 1.74 to 3.30 m/d and also increases with increasing permeability of cores in our experiments. Within the range from Vce to Vcr, elongational flow occurs although the HPAM solution still exhibits pseudoplastic behavior. Beyond Vcr, the strain viscosity increases rapidly with velocity and straining flow governs the flow behavior. The results from core flowing tests showed that the displacement efficiency evidently increases with the velocity beyond Vce and reaches a maximum when the velocity approaches Vcr. The model index B (renamed Han&#x92;s index in this paper) describing the viscoelasticity of HPAM in porous media [1] has been proved to be the relaxation time for HPAM molecules[2]. The effect of property parameters of both porous media and polymer solution on Han&#x92;s index, H, was investigated by core flowing tests with artificial cores. The property parameters include injection rate, salinity, hydrolysation degree of HPAM and core permeability. A comprehensive Han&#x92;s index, He, was obtained as a function of these parameters by using multi-variable regression. Polymer flow tests in cores showed that the relative increment of displacement efficiency varies with He as a normal distribution function, i. e., there exists a optimum He which leads to a maximum of the oil recovery.
To investigate the influence of the rheological behaviour of HPAM on the prediction of on recovery in polymer flooding, one dimensional numerical simulation was conducted.
It is believed that viscoelastic behaviour will inevitably occur during HPAM solution flushed through oil formation and it plays an important role in oil recovery. Viscoelastic property of polymers should be considered as a screening criterion and it is necessary to take into account the viscoelastic effect in polymer flood numerical simulation.
Innovative Technologies Improve The Profitability Of Offshore Heavy Oil Marginal Fields.
Authors: Giuggioli A. , De Ghetto G. 
Published: December 2007

ABSTRACT
The paper summarises a conceptual study carried out by AGIP for the development of offshore marginal heavy oil fields in the Adriatic sea (Italy).
On the basis of this study a comprehensive R&D programme was started, in order to validate the innovative technologies proposed.
The considered field size, with OOIP in the order of 80-140 million of ST bbl and the quality of the oil with a gravity around or less than 10° API, makes the conventional production schemes economically non viable.
The paper discusses some alternative development schemes based on the following innovative technologies. Fluidification and transportation of heavy oils via oil-water dispersion;Artificial lift of heavy oils with jet pump by using water as motive fluid;Multiphase pumping of the produced oil-water emulsion, from platform to shore;Light, reusable, unmanned platform.
A comparison of the principal economic indicators of the innovative proposed solutions versus the traditional ones is presented.
The new production schemes allow development of offshore heavy oil fields with costs saving of as much as 30 %.