bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multi-Criteria Decision Making in Strategic Reservoir Planning Using the Analytic Hierarchy Process
Authors: Gerbacia William E. , Al-Shammari Hanaa 
Published: December 2007

Abstract
The paper describes the use of the Analytic Hierarchy Process in the strategic planning for the development of a series of reservoirs in the same field. A department of the Kuwait Oil Company is responsible for the development of these reservoirs and needed to determine the best order in which to develop these assets. In order to do this it was necessary to make judgements regarding how well any development option met a set of strategic criteria. At the individual reservoir level, it was also necessary to judge which development option best met a set of criteria for the development of specific reservoirs.
A decision hierarchy was developed that reflected the ordering of the criteria and the specific alternatives. Pair-wise comparisons of the various criteria were made in order to determine how well they satisfied the overall objective. These judgments were evaluated using a judgment matrix to determine weights for the criteria. These criteria were applied to decisions to be made at the next lower level in the hierarchy. In this way, the decisions, which were judged to best meet the overall objective, were given the highest priority. This influence cascaded down through the hierarchy to rank the development options. With this structure it was simple to substitute one overall objective for another to determine whether this would cause a change in decision policy.
The sensitivity of the decision outcome was also evaluated for its sensitivity to the range of values of the input factors. Since there were thirty-five factors to evaluate, a statistical design approach was used to evaluate factor effects. It is shown that the planning factors, planning horizon and the demand scenario used for planning purposes were significant in all cases evaluated, and highlighted the importance of testing the assumptions, criteria and objectives in a strategic planning exercise.
Corrosion Consequences of Oxygen Entry Into Sweet Oilfield Fluids
Authors: Martin Richard L. 
Published: December 2007

Abstract
This paper contains the results of laboratory and field tests where the corrosion system was carbon steel exposed to oilfield brines containing dissolved carbon dioxide and oxygen. Both uninhibited and inhibited systems were examined. The results are analyzed and placed in context with previously reported work dealing with related systems.
Oilfields, in general, have less gas pressure as they mature. Ingress of oxygen into well annuli, into the vapor space in tanks, and through pump packing becomes more commonplace as a result. The corrosion consequences of this condition can now be quantified and corrective action can be taken to avoid equipment replacement and production losses.
To the author's knowledge, no report of a systematic treatment of this subject exists in corrosion literature. Quantification of the effects, recognition of duration, and influence of corrosion inhibitor chemical types are among the novel contributions of this paper.
Some of the significant conclusions from the work concern the magnitude and persistency of corrosion acceleration by oxygen in sweet fluids. At common oil well temperatures, acceleration was in the order of 10 to 30 mpy per part per million of oxygen. The concentration of oxygen was not reduced preferentially from these solutions but occurred at approximately the same rate as reduction of dissolved carbon dioxide (undissociated carbonic acid) concentration. Inhibition of corrosion in CO2/O2 systems was more difficult that in CO2 alone but could be accomplished.
Large Scale Field Gathering of Oil-Water-Gas at Temperature Below the Pour Point of Crude Oil Successful
Authors: Wang Demin , Song Chengyi , Gong Xiaohong , Cheng Jiecheng , Li Qun , Wu Di 
Published: December 2007

Abstract
Gathering of Oil-water-gas mixtures in oil fields is usually performed on condition that the gathering temperature is above the pour point of the crude oil or above the paraffin precipitation temperature. Therefore, all the mixtures that are gathered are in a fluid state (liquid and gas). However, when gathering crude oil that has a high pour point and high paraffin precipitation temperature in cold regions, the mixture must be heated to maintain the high temperature and a large amount of energy is consumed.
Daqing Oil Field experimented on a large scale (2,300 wells) in the field the gathering of oil-gas-water at temperatures lower than the crude oil pour point, which means that the mixture is gathered simultaneously as a sticky solid (crude oil), gas and liquid (water). This paper introduces the results in the laboratory of adding a Fluid Phase Conversion Agent into the mixture and the characteristics of the mixture at different temperatures. The paper also introduces the field results of adding a Phase Conversion Agent to the gathered fluid, the problems that arose and how they were solved.
The field results of gathering produced fluids from more than 2,300 wells are very good. The gathering of produced fluids proceeded normally, energy consumption and gathering costs were lowered. At the same time, some actual data on the rheology of simultaneous gathering of a sticky solid, liquid and gas was obtained.
Emulsion Formation in a Model Choke-valve
Authors: Janssen P. H. , Noik C. , Dalmazzone C. 
Published: December 2007

Abstract
A problem in mature oil fields is the large amount of water produced alongside the oil. At the moment that both phases are leaving the wellbore of an oil well, tight water-in-oil emulsions can be formed due to the turbulence in the choke-valve at the wellhead. This flow process was simulated in the laboratory, by pumping crude oil-brine mixtures through a model choke-valve represented by a calibrated orifice. The parameters varied were the water-cut, the production flow rate and the orifice dimensions. The water-in-oil emulsion droplets were encapsulated immediately after formation and the emulsion characteristics, i.e. droplet-size distributions and water fraction were determined by optical microscopy and DSC.
The results of the experiments revealed that water-in-oil emulsions could be formed in the choke-valve if a certain critical value of the average energy dissipation rate was exceeded. This critical value depends on the type of crude oil and on the oil-water ratio. The diameter of the emulsion droplets found in the experiments could be explained in the framework of inertial and viscous break-up theories.
In experiments with a crude oil with little asphaltenes the droplet diameters were in the order of the Kolmogorov length scale and the average diameter Dav of the emulsion droplets decreased with increasing energy dissipation rate ε following a power-law relation: Dav∝ ε n. The value of the exponent n was found to be −0.3 and −0.1 at a watercut of 30 vol.% and 50 vol.% respectively. In experiments with an asphaltenic crude oil, the final droplet diameter was determined by viscous forces, probably due to relaminarising flow conditions.
This paper gives new information with respect to the characteristics of brine-in-crude-oil emulsions being formed in a model choke-valve and can be used to obtain insight in the emulsion formation problematic at the wellhead of an oil well. Additionally, the paper provides data on the size of droplets formed in turbulent and laminar flow at high dispersed-phase fraction.
Multiphase Flow Metering: Current Trends and Future Developments
Authors: Falcone G. , Hewitt G. F. , Alimonti C. , Harrison B. 
Published: December 2007

Abstract
Over the last decade the development, evaluation and use of MFM systems has been a major focus for the Oil & Gas industry worldwide. So far, many alternative metering systems have been developed, but none of them can be referred to as generally applicable or universally accurate. Both established and novel technologies suitable to measure the flow rates of gas, oil and water in a three-phase flow are reviewed and assessed within this framework. Those technologies already implemented in the various commercial meters are then evaluated in terms of operational and economical advantages or shortcomings from an operator point of view. The lessons learned about the practical reliability, accuracy and use of the available technology are discussed. As operators now realise, incorporation of MFM's is an essential step in exploiting marginal fields. A new approach to flow assurance, deep water developments, downhole/seabed separation systems and wet gas fields is foreseen. The paper suggests where the research to develop the next generation of MFM devices will be focused in order to meet the as yet unsolved problems.
Optimization of High-Gas
Authors: Agar Jo 
Published: December 2007

Abstract
This paper addresses the inherent difficulties associated with the proper optimization of High-Gas production. The MultiPhase Flow Meter (MPFM) described allows the in-line measurement of all three phases (oil, water and gas) simultaneously without separation of the production. The paper first defines the inherent difficulties associated with the accurate measurement oil, water and gas using conventional 2 & 3 phase separators. Defines problems associated with MultiPhase flow and its proper measurement. Next, the paper describes the problems associated with Gas-Lift production and its accurate measurement and optimization of the process.
This paper then describes the Multi-Phase technology: its uses and benefits. The Agar Multi-Phase Flow Meter measurement technique is described as well as, solutions to High-Gas multiphase measurement. Finally, the paper shows several multiphase applications and field trial results of those applications.
An Evaluation of Post-Waterflood Depressurisation of the South Brae Field, North Sea
Authors: Drummond A. , Fishlock T. , Naylor P. , Rothkopf B. 
Published: December 2007

Abstract
Depressurisation of waterflooded reservoirs can economically increase recovery and extend the life of mature fields. The process is underway in the Brent Field in the North Sea [1] and is under evaluation in several others [2]. Most of the previous published studies on depressurisation have focused on the critical gas saturation as the crucial factor in determining the recovery potential [3,4]. Recent experiments using reservoir condition, three-phase in-situ saturation measurements have enabled critical gas saturations and gas relative permeabilities to be determined during depressurisation [5]. This work has shown conclusively that conventional external gas drive experiments do not represent the depressurisation process and that actual gas relative permeabilities can be several orders of magnitude lower than conventional data.
This paper describes the modelling of results from an experimental coreflood, and demonstrates the effect of using the resulting relative permeability curves in a full-field simulation of depressurisation in the South Brae field. The results indicate that less hydrocarbons are produced then predicted in earlier field assessments and emphasizes the need for representative experimental measurements when making field development plans.
Application of Thermophilic Microbes In Waxy Oil Reservoirs at Elevated Temperature
Authors: Feng Qingxian , Zhou Jiaxi , Ni Fangtian , Chen Zhiyu , Liu Rulin 
Published: December 2007

Abstract
For the last decade, some specifically selected microbes have been successfully used to improve oil recovery in some waxy or heavy oil reservoirs. The main feature of this new technology is that the applied microbes can degradate heavy oil components to improve oil properties, for example, reduction in oil viscosity or cloud pour point. However, successful application of microbial technology in high temperature reservoirs has been remaining a challenge due to quick disactivate of microbes at elevated temperature. In this work, we present the result of application of self-incubated thermophilic microorganisms that are growing at a reservoir temperature of 73°C.This microbes can self-colony and quickly grow up at the reservoir conditions. The analysis of the crude oil on samples before and after treated with microorganisms showed that (1) oil viscosity decreased by 34%, (2) pour point decreased 3°C, (3) the weigh of heavy oil components decreased significantly, and (4) the interfacial tension between oil and formation water decreased about 31%. In addition, the pH value of the crude oil samples decreased from 7.3 to 5.5. The results from coreflooding tests showed that the oil recovery could be improved by 6.6%(OOIP) by injection the microbes. We also performed a‘ huff and puff pilot test in a production well that having 91% of water cut before the test. The results showed that after the well was stimulated with the microbes, the oil production rate increased from 20 to 40 barrels per day, and the water cut decreased from 91% to 87.8%. The effect of the stimulation with the microbes continued more than 6 months and the total oil incremental was than 2400 barrels.
Deployment of Multiphase Pumps on a North Sea Field
Authors: Leporcher Emile , Delaytermoz Alain , Renault Jean-François , Gerbier Alain , Burger Olivier 
Published: December 2007

ABSTRACT
During the past years, the Oil and Gas industry has invested a lot of resources in the development of the multiphase technology (flow modelling, multiphase production equipment, fluid-related effects). The POSEIDON programme aimed at developing multiphase pumping based on the rotodynamic helico-axial design. This technology has been qualified with two tests on onshore fields. After an extensive comparison with conventional alternatives involving separation, compression, pumping, additional pipeline, it has been decided to install a multiphase boosting station on the offshore DUNBAR field in the North Sea. This paper will present a summary of the qualification tests, the Dunbar field case, the comparison between several export alternatives, the reasons for the selection, the export system over 22 km, the multiphase boosting station (two 4.5MW units) and installation related issues. Field experience after more than a year of operation will be discussed.
Multiphase Pumps for 250,000 bbl/D Field Development
Authors: Pershukov V. A. , de Salis J. , Cordner M. 
Published: December 2007

Abstract
The production from an entire oil field, or a substantial field area can be achieved by using multiphase pumps (MPP), either on their own or in conjunction with some well activation techniques (electro submersible pumps, gas lift, etc). MPP are applied for oil fields with a GOR generally in the range of 100 to 1000 scf/bbl, extending sometimes to higher values.
It can be seen from this paper that MPPs can realistically be considered to represent a viable and proven solution for oil field developments up to about 250,000 bopd. This is due to the development of higher capacity helico-axial pumps which are now capable of handling total volumetric (actual flow at pump inlet: oil, gas and water) capacities in excess of 500,000 bpd (3,300 m3/h).
The use of MPP is especially advantageous for remote fields in inhospitable environments where unmanned facilities are preferred.
The pump is of the barrel casing design with an axially split inner casing, incorporating conventional mechanical seals and bearings. A pressurised seal system (similar to a standard Plan 53 system) prevents gas leakage or solid particles contaminating the bearing area and ensures that a liquid film is always present at the seal faces even when the pump is operating under dry running conditions. An overpressure of approximately 5-10 bar is maintained between the seal fluid circuit and the product side of the mechanical seal.
The inner casing and hydraulic components is generally supplied as a cartridge or pull-out block for A case is described where four high capacity and high power (up to 8,000 HP or 6,000 kW) helico-axial multiphase pumps have been selected to overcome a pipeline capacity restraint at the Priobskoye oilfield in Siberia. This field is operated by JSC Nefteyugansk, part of Yukos.
Application of Wavelet Transform to Analysis of Pressure Transient Data
Authors: Soliman M. Y. , Ansah J. , Stephenson S. , Mandal B. 
Published: December 2007

Summary
Although the mathematical concept of "wavelet transform" was developed in the early part of the 20th century, it did not receive practical application until the 80's. Wavelet Transform is now used in a wide variety of applications in the areas of medicine, biology, data compression, etc. A significant benefit provided by Wavelet Transform is its capability to provide two functions:
smoothing of the basic signal, and retention or even enhancement of the details.
In data analysis, these characteristics allow the user to quickly recognize hidden signals. In well testing, these capabilities would enhance signals that can be masked by other events or by the data frequency itself. Since the derivative techniques currently used in well testing tend to smooth data and conceal certain events, the use of the wavelet transform to analyze the raw data could prove to be very valuable as a major step in enhancing the techniques of modern analysis of data.
This paper will very briefly review application of the wavelet transform methodology to data analysis in general and will show why its application to well testing data in particular is important. It will also provide guidelines for application of this technology to well testing.
Several field examples are provided to demonstrate the application of the wavelet transform to well testing and how the qualitative and quantitative use of the method determines wellbore anomalies, boundary effects, and other well testing phenomena.
Permanent Downhole Monitoring For Extreme Temperature and Pressure Environments
Authors: El Chiriti Kamal , Moffatt Terrence G. , Bussiere Colin 
Published: December 2007

Abstract
This paper directly addresses a field proven reliable solution for permanent monitoring in high temperature and high-pressure (HT/HP) oil and gas well environments. The petroleum industry has struggled with a solution for monitoring in these environments for years and is continually held back by the limitations of electronics at elevated temperatures.
The development of cutting edge surface electronics has enabled a remote sensor to be queried and the output frequency signal to be interpreted from several miles away. What makes this unique is that electronics are not required downhole. Low-level frequency signals are extracted directly from the sensor via a cable and are directly related to measured parameters. Modern digital signal processing techniques are used to eliminate noise and measure the frequencies to a very high degree of accuracy and resolution. The millivolt level signals, which were once unidentifiable, can now produce pressure and temperature measurements with resolutions suitable for reservoir analysis.
The elimination of the downhole electronics has resulted in the ability to operate many years at temperatures well above the current limitations of electronics. In addition to high temperature operation the elimination of downhole electronics has improved the reliability of permanent monitoring substantially. This increase in reliability is demonstrated from PDVSA’s use of the technology in the Cueta Field located in the southern region of Venezuela’s, Lake Maracaibo. One hundred percent (100%) of the sensors are operational, some of which were installed over four years ago. These results are quite favorable when compared with industry published reliability statistics of less than 55% for electronic technologies at much lower temperatures.
This paper will focus on PDVSA’s experiences in their HT/HP field in South Lake Maracaibo, compared with two recent studies performed on electronic based permanent downhole monitoring (PDM) systems.
Optimizing Miscible Injectant (MI) Composition for Gas Injection Projects
Authors: Lee Sheng-Tai , Moulds Tim P. , Narayanan Ram , Youngren Gary , Lin C. Y. , Wang Yun 
Published: December 2007

AbstractMany gas injection projects can flexibly design injectant gas compositions through sources of gas and enriching fluids. In such instances, optimization of the injectant composition for project efficiency becomes important and necessary. Based on experiences from BP gas injection projects, we present a procedure to optimize miscible injectant (MI) compositions for field projects. This procedure emphasizes an integrated interpretation and screening from fluid PVT, facility processes, prediction of minimum miscibility conditions to 1-D and field scale compositional model results.To demonstrate the factors that affect design of an optimal MI, we presented two field processes, which have contrasting mass-transfer mechanisms: one a vaporizing-dominated mechanism and the other condensing-vaporizing.For a vaporizing-dominated displacement process, slim-tube MMP is not sensitive to MI compositions. However, different MI compositions, having the same MMP (minimum miscibility pressure), do not necessarily have the same field-scale recovery efficiency. Analysis and understanding of the role of each MI component in the slim-tube mass transfer process gives important insight to optimize the MI composition.Enriching MI above the slim-tube MME (minimum miscibility enrichment) or MMP brings about additional EOR oil in a field process. The key mechanism for the above to occur is through further reduction of residual oil in the MI swept reservoir portions. The additional oil recovery is significant; yet the benefit must be evaluated with respect to MI supply and its utilization.MI compositions can affect surface oil rate through different mass-transfer mechanisms occurring at facility separations. Such an effect is particularly notable for volatile and light oil systems.The optimal MI must be assessed in terms of incremental EOR oil recovery, net MI efficiency and MI cost. Considerations from field processes, e.g. facility constraints and effects of reservoir processes, may therefore alter the optimal MI derived from 1-D slim-tube processes.
Numerical Modelling and Parametric Analysis for Designing Propellant Gas Fracturing
Authors: Yang David W. , Risnes Rasmus 
Published: December 2007

Abstract
This paper presents a numerical modelling of propellant gas fracturing processes, which may be used as a quantitative tool for controlling and optimizing the pressure pulses generated by propellant combustion under the down-hole conditions. The model consists of propellant combustion, well fluid compression and movement, fluid drainage through perforations, fracture extention and flow in fractures. By using a proper algorithm, the pressure profile is calculated step by step. The paper also derives the formulae for estimating the productivity increase achieved by multiple fractures. The models have been verified by comparing with lab experiment and field measurements. Besides, the paper also discusses the method of estimating the productivity increase made by the propellant gas fracturing and the main factors of influence.
Based on the numerical model, the paper also discusses the method for designing propellant gas fracturing, including a parametric sensitivity study of propellant charge, well completion, perforation and formation properties, etc.