bluuebunny/crossref_metadata_2025_split huggingface dataset:
Key Issues and Operational Challenges in the Use of Dispersants
Authors: Quek Qiuhui 
Published: December 2009

Abstract
In the Torrey Canyon incident, 41 years ago, environmentally unfriendly ‘chemicals’ with highly aromatic solvents were used in large quantities. These were highly detrimental to the environment triggering countries to enforce regulations on the use of oil spill treatment chemicals. Organisations which opted to use dispersants faced stringent requirements and in addition, they also faced dispersant toxicity and effectiveness issues and operational challenges.
National government policies may place restrictions on the use of dispersants such and other constraints such as water depth and distance away from sensitive coastlines. They may also maintain a list of approved dispersants which have been tested for efficacy and toxicity which end-users must be aware of and in compliance with.
Besides having to clear the stringent regulations set by the authorities, ‘window of opportunity’1 for effective spraying have to be taken into account. These can be identified by laboratory and / or field test under the conditions expected. Key parameters that require consideration are the sea state, water temperature and other environmental conditions2 that could either enhance or inhibit the process of dispersion
Usage of dispersant during an oil spill response poses certain operational challenges. Issues such as staging and working areas that would offer the shortest possible time must be taken into account. These include distance to the spill site and transit time for the replenishment of dispersant stockpile. Availability of deployment equipment and trained personnel are often logistically challenging and these preparedness issues can lead to an extended response time.
This paper will discuss the key issues and challenges faced during an oil response using dispersant spraying strategy with the aid of case studies from spill response operations in Libya, Korea and Angola.
Flaring, Gas Injection and Reservoir Management Optimization: Preserving Reservoir Energy Maximizes Recovery and Prolong the Life of an Ageing Brown Field
Authors: Moreno J. , Badawy A. , Kartoatmodjo G. , AlShuraiqi H. , Zulkhifly F. , Tan L. , Friedel T. 
Published: December 2009

Abstract
Reservoir management is a standard industry practice to maximize oil recovery; however, in mature fields the full potential is often not realized. Unlike greenfield developments, mature oil fields deal with existing infrastructure and fluid export schemes with capacities designed for peak production sometimes decades ago and/or different production techniques.
Substantial increases in producing gas-oil ratios and water production can occur over the lifetime of the field. Falling reservoir pressures cause not only a drop in manifold pressures and the need for artificial lifting technologies, but potentially may also lead to the necessity of flaring associated gas if no appropriate compression facilities are available. Metering and surveillance facilities as well as reservoir management infrastructure are often basic and represent the technology available at the time of the platform installation.
The current paper discusses optimization techniques, using dynamic simulation with a coupled surface to reservoir model, to show how flaring affects gas injection on field scale. The extensive study was conducted for a thin oil rim Brownfield at the upper limit of the current handling facilities. Two gas injectors in the gas cap aid the reservoir energy by re-injecting a portion of the produced gas.
The study showed that flaring over longer periods of time potentially caused a rapid decline in reservoir energy and thus shortens the life of the field. This in turn causes the deferral of a substantial amount of oil production. Further analysis was conducted investigating ways to extend the life of field. A solution is proposed to enhance the ageing infrastructure and modifying the current reservoir management practices at low cost. It was shown that the elimination of flaring does not only help in protecting the environment but is also attractive when there is an increase in energy demand.
New Advance in Numerical Well Testing through Streamline Simulation
Authors: Jun Yao , Shiyi Zheng 
Published: December 2009

Abstract
Numerical well testing technique has been regarded as the future of well testing in tackling non-linear, heterogeneous reservoir testing problems. Finite difference and finite element methods were used before in the construction of the well testing model, which was proved worked well for the most practical cases.
In this study, streamline simulation techniques was further developed for numerical well testing purpose, in which production history, reservoir heterogeneity, multi-well interference as well as oil-water two phase flow problems were all considered. Streamline well testing model was developed to analyze pressure draw down and build up under these field conditions.
In the developed well testing mathematical models along each streamline, equations were solved all together numerically to derive transient pressure solutions for draw downs and build ups. Results such as pressure distributions, field saturation maps and the distribution of streamlines can all be produced through the developed simulator and visualized.
It was proved through both theoretical study and a practical field example that the developed streamline well testing algorithm is faster, robust and reliable to use for complicated well test interpretations.
A Case History: First Real-Time Digital Flow Profiling of a Passive Inflow Control Device (ICD) Completion
Authors: Hembling Drew , Soremi Adeyinka , Carter Neale , Naldrett Garth 
Published: December 2009

Abstract
While adapting Advanced Well Completions (AWC) in horizontal wells has provided significant improvements in reservoir deliverability and depletion, it has also resulted in increased data gathering challenges for the longer and deeper completions, in particular, the options to perform well logging are reduced, and the costs are high. This is related to both the costs of the more advanced horizontal well logging tools and the more expensive logging methods, such as coiled tubing and tractor systems, used for the conveyance of these tools into the wellbore.
In an effort to acquire high quality downhole data in a timely manner from passive Inflow Control Device (ICD) completions, Saudi Aramco set about investigating the alternatives to traditional production logging methods. A technology gaining greater industry acceptance in recent years, is the permanently installed Distributed Temperature Sensing (DTS) and this technology has become the focus of investigation. The limitations of single point permanent Downhole Pressure Monitoring (PDHM) and DTS technology were soon realized. In particular, the limited temperature resolution from DTS and discrete point PDHM readings, were not sufficient for evaluating horizontal wells. At the time of investigation a new generation of DTS technology became commercially available, providing a ten-fold improvement in measurement resolution. This allowed Saudi Aramco to proceed with field trials for this new technology.
This paper will present the case history from the world's first installation of DTS in a horizontal ICD completion while showing the advanced well completion design and the data from the field trials. The paper will also indicate the future of DTS in advanced well completions.
Behavior Based Safety Simultaneous Deployment for Office and Field Based Workforce
Authors: Syauki Faris , Basri Hasan 
Published: December 2009

Abstract
Recognizing that there is a behavioral component in which contributes over 80 percent factors lead to accidents, while current safety initiatives are mostly focusing on systems, conditions and/or procedures rather than on people's behavior, started in 2007, Chevron IndoAsia Business Unit (IBU), has decided to implement the Behavior Based Safety (BBS) as one of key safety initiatives which aimed at preventing injury to workforce through reinforcement of safe behaviors and reduction of at-risk behaviors in the workplace.
Chevron-IBU BBS program implementation is a significant and important initiative. The scope covers 7,062 employees and 12,275 contractors at 4 Operating Group (OPG) located in various locations, on shore and off shore, oil & gas and geothermal & power operations (GPO), scattered thousand miles away on 3 different islands across Indonesia.
This paper mainly describes the simultaneous deployment in field and office environment which scope covers 1,063 employee and 1,119 contractors at 4 different locations: 3 separated sites of GPO and Jakarta Office, Chevron-IBU Headquarter.
There are several different approaches conducted in deploying the plan at each location to ensure the buying in of this initiative, which includes BBS process governance, leadership involvement, resources allocation and promotional/training plan.
The information provided in this paper could be helpful for any industries deploying BBS program in field and/or office environment.
By the end of 2008, the deployment timeline has been running as planned into a full cycle process. Steering Committee's BBS related skills have been developed through several mandatory workshops. More than 700 workforces have been trained as BBS Observer, conducted more than 5,000 observations in which around 60,000 safe behaviors have been reinforced and around 6,000 at risk behaviors have been identified and being subject for mitigation plan.
Laboratory Evaluation of Alkali and Alkali-Surfactant-Polymer Flooding Combined With Intermittent Flow in Carbonatic Rocks
Authors: Bortolotti V. , Macini P. , Srisuriyachai F. 
Published: December 2009

Abstract
Conventional alkali flooding in numerous carbonatic reservoirs is often not effective due to insufficient contact time to reverse rock wettability from oil-wet into a more favorable condition to get the highest ultimate oil recovery, i.e., water-wet or partially water-wet conditions. Therefore, conventional flooding might be not completely efficient and/or adequate. Applying intermittent flow helps rock surface to complete its wettability reversal and to improve the final oil recovery. In the present study, laboratory evaluations of alkali and Alkali-Surfactant-Polymer (ASP) flooding combined with intermittent flow are presented and comparatively discussed. An alkaline solution is injected into oil-wet homogeneous carbonatic core samples and aged for a week. This aging period represents an "intermittent flow" which allows rock surface to reach a more favorable condition for oil recovery; oil is repulsed from the rock surface and the core is then flooded by displacing brine. Core flood test is performed vertically in order to avoid the early breakthrough of injected water phase. In the solely alkali flooding, the results demonstrates that the concentration of alkali strongly affects the flooding efficiency. Alkali concentration is intentionally kept low. In fact, high alkali concentration (of about 0.5 molar) is not recommended because the insolubility of in-situ soap (soap produced by the reaction of the alkaline substance with the acid present in the oil phase) causes pore space plugging and therefore permeability reduction. The application of intermittent flow is therefore less significant in the case where high initial water saturation is present. The second part of this study emphasizes on alkali-surfactant-polymer flooding. In particular, laboratory tests highlighted that the highest final oil recovery with the lowest Water-to-Oli Ratio (WOR) is obtained by aging the alkaline solution after the injection of a surfactant, and then flooding the whole system by a polymer solution.
Fractured oil-wet carbonatic reservoirs seem the best candidates for the application of this technique since aging time would allow alkali to diffuse and reverse rock wettability also in otherwise unaccessible zones. The proposed technique seems very effective to increase the ultimate oil recovery of these reservoirs. Traditionally, alkali flooding in oil-wet carbonatic reservoir is believed to require the consumption of a large mass of alkaline substances. However, the mass of this substance is responsible for the wettability reversal into a more favorable condition for oil recovery, and can be acceptably managed by a proper design of the flooding parameters.
A Risk-Based Approach for Well Integrity Management Over Long Term in a CO2 Geological Storage Project
Authors: Le Guen Y. , Meyer V. , Poupard O. , Houdu E. , Chammas R. 
Published: December 2009

Abstract
Carbon Capture and Storage, as a solution to mitigate the increase in greenhouse gases emissions in the atmosphere, is still bringing intensive worldwide R&D activities. In particular, significant acceleration of in situ CCS experiments supports technical developments as well as acceptability of this technology. Among the major risks identified to this technology, wells are often considered to be the weakest spots with respect to CO2 confinement in the geological reservoir. Therefore, long-term well integrity performance assessment is one of the critical steps that must be addressed before large scale CCS technology deployment is accepted as a safe solution to reduce CO2 emissions.
A risk-based methodology associated with well integrity is proposed within CO2 geological storage. The main objectives of this approach are to identify and quantify risks associated with CO2 leakages along wells over time (from tens to thousands of years), to evaluate risks and to propose relevant actions to reduce unacceptable risks. The methodological framework emphasized the use of the risk concept as a relevant criterion to (i) evaluate the overall performance of well confinement with respect to different stakes, (ii) include different levels of uncertainty associated to the studied system, and (iii) provide a reliable decision making support. For the quantification of risk, a coupled CO2 flow model (gas flow and degradation processes) was used to identify possible leakage pathways along the wellbore and quantify possible CO2 leakage towards sensitive targets (surface, fresh water, any aquifers…) for different scenarios. This approach offers an operational response to some of the challenges inherent to well integrity management over well lifecycle.
This paper focuses on the application of the methodology to a synthetic case based on an existing well. The practical outcomes and the added values will be presented: (i) an objective and structured process, (ii) scenarios identification and quantification of CO2 migration along the wellbore for each scenario, (iii) risk mapping, (iv) and operational action plans for risk treatment of well integrity.
Deepwater Completion Designs: A Review of Current Best Practices
Authors: Ceccarelli Tomaso , Albino Eduardo , Watson Graham , Deffieux Damien 
Published: December 2009

Abstract
The advent of deepwater drilling and the increasing number of deepwater discoveries have led the energy industry to develop new completion design philosophies and technologies for challenges that did not exist in the oilfield less than a decade ago. As a result, the numerous deepwater developments and the experience gained have led to new levels of efficiency and reliability in completion design; risk and economics analysis have joined the technology, safety, and environmental aspects in educated decision processes.
Two challenges in particular have created opportunities for advancement. First, rig-time costs for operating in deepwater are so high that efficiency and reliability had to be emphasized to minimize nonproductive time during completion installation. The result was the development of special tools and techniques that allow operators to reduce the number of trips in the hole and to accelerate online time on the drill floor.
The effort to decrease nonproductive time paralleled a second important objective: increasing the time of field reliability. Because many deepwater wells are subsea, intervention operations and costs are prohibitive; thus, completions must be designed to minimize or eliminate the need for interventions during the life of the well. This objective intensified the need for better equipment designs with respect to longevity, corrosion, and erosion-resistant materials, work rating specifications, and remote monitoring and control equipment.
Although some deepwater projects are completed with dry trees from platforms, this article focuses on subsea wells and the major drivers that have differentiated their completion design processes from those of conventional designs. It also compares some of the solutions adopted to address risks and economic issues and discusses how these solutions vary according to corporate design philosophies and local best practices. Examples of design solutions are discussed for various deepwater areas, including the Gulf of Mexico, West Africa, and Southeast Asia.
Interaction between Induced Hydraulic Fracture and Pre-Existing Natural Fracture in a Poro-elastic Environment: Effect of Pore Pressure Change and the Orientation of Natural Fracture
Authors: Rahman M M , Aghighi Ali , Rahman Sheik S 
Published: December 2009

Abstract
This paper investigates the effect of pore pressure change on the interaction of induced hydraulic fracture and natural fracture and the effect of natural fracture orientation. Warpiniski and Teufel's interaction criteria were adopted to evaluate the fracture propagation that would occur after an induced fracture intersects an existing natural fracture.
A fully coupled finite element based model is used to simulate hydraulic fracture propagation in a poroelastic formation with existing natural fracture. In order to study the effect of pore pressure change on interaction zone, a poro-elastic solution for the stresses in the interaction zone has been used as a basis for fracture interaction criteria. From the results of this study, the followings were observed when the induced fracture interacts with the natural fracture with changing pore pressure. ○At low angles of approach with low to high differential stress, the induced fracture is arrested by the natural fracture, then the natural fracture begins to open, diverting the fracturing fluid and preventing the induced fracture from crossing.○At medium (60 deg and above) angles of approach fracture opening and crossing both was observed depending on the differential stress. In low differential stress opening occurred and in high differential stress (more than 600 psi) induced hydraulic fracture cross the natural fracture.○At high angles of approach crossing occurred at all differential stresses.○Pore pressure change does not have any direct impact on interaction type but it accelerates the reinnitiation pressure needed to cross the natural fracture. The pressure build up rate inside the natural fracture is influenced by the pore pressure change.
This paper depicts that the effect of pore pressure change and the orientation of the natural fracture is of immense significance in hydraulic fracture propagation when it interacts with natural fracture. The study includes small to large natural fracture and low permeable formation.
Well Test Analysis in Naturally Fractured Gas Condensate Reservoirs Below Dew Point Pressure
Authors: Al-Baqawi A. M. , Al-Malki B. H. 
Published: December 2009

Abstract
Gas condensate reservoirs below dew point pressure have been the subject of many studies in the petroleum literature. These studies investigated the impact of the resulting liquid condensate drop-out on well performance and concentrated mainly on reservoirs with homogeneous behaviors.
This paper focuses on the effect of condensate drop-out in naturally fractured carbonate reservoirs with double porosity behaviors and on the changes in well test responses due to changing oil/gas relative permeabilities. Specifically, this paper examines the impact on the storativity ratio (ω) and the interporosity flow coefficient (λ) below the dew point pressure as the radius of the condensate bank increases away from the wellbore. By generating well test responses under different operational well conditions below the dew point pressure, the paper shows that λ decreases due to two-phase flow in the reservoir, whereas ω shows very little change. The condensate bank appears as an additional skin effect, as in reservoirs with homogeneous behavior. This skin can be removed temporarily by hydraulic fracturing.
Conclusions of the paper are verified with well test data from a carbonate formation in the Middle East and compositional simulation models.
Appraisal and Development of Thin Oil Rims Using the Smart Field Approach, An Example from Champion West, Brunei
Authors: Bakker Peter , Watts Lee , Salakhetdinov Ravil , Liew Yee-Yung , Dale Brigitte 
Published: December 2009

Abstract
The economic development of thin oil rims associated with large gas caps in multi-stacked reservoirs presents many challenges. In the structurally complex Champion West field, offshore Brunei, innovative well designs together with detailed subsurface studies have unlocked thin oil rims. Earlier development phases comprised deviated and snake wells with multi-zone smart completions. In some areas these wells have resulted in cross-fault depletion of the remaining smaller oil targets. An appraisal strategy was put in place to address the major uncertainties associated with the smaller targets, such as complex fluid distribution and connectivity to existing producers. This strategy comprised drilling pilot holes from development wells, which were evaluated using advanced mud gas logs, downhole pressure measurements and wireline/ logging whilst drilling (LWD) logs to confirm fluid distribution and understand connectivity. This paper discusses one such example, where production data from smart wells has been incorporated with appraisal data to optimise well design, placement and production from a thin depleted oil rim. Multi-rate test information has been used to adjust down-hole inflow control valve (ICV) settings, initially to balance drawdown along the horizontal wells and later to minimise water and gas cap production.
Combustion Performance and Emissions of Methyl Ester of Some Vegetable Oils in a Water-Cooled Furnace
Authors: Ghorbani Afshin , Shahraki Bahram Hashemi , Shariati Ahmad 
Published: December 2009

Abstract
An ever increasing demand of fuels has been a challenge for today's scientific workers. The fossil fuel resources are dwindling day by day. Biodiesel has become more attractive recently because of its environmental benefits and the fact that it is made from renewable resources and seems to be a solution for future. Food consumption around the world produces large amounts of waste vegetable oils and fats that, in many world regions, are disposed of in harmful ways. Consequently, this study intended to investigate the feasibility of utilizing this renewable and low cost fuel raw material as a diesel fuel replacement in small scale applications such as in residential heating boilers. Specifically, the study examined the aspects of combustion performance and emissions of biodiesel relative to the baseline diesel fuel in a water-cooled furnace. The combustion efficiency, ηc, and exhaust temperature, Texh, as well as the common pollutants and emissions were tested over a wide range of air/fuel ratio ranging from very lean to very rich. All tests were conducted at two different levels of energy inputs for the fuels. The findings showed that at the tested levels of input energy, biodiesel combustion efficiency was a little inferior to that of diesel fuel due to its higher density and lower heating value while on the other hand, from emissions view points, biodiesel emitted less pollutants at the whole range of A/F ratio considered.