bluuebunny/crossref_metadata_2025 huggingface dataset:
Mud Gas Isotope Logging using Mass Spectrometry
Authors: Nair Amith , Kurawle Irfan , Kaul Mohit , Mahalle Nakul , Thomas Timmy , Shivanikar Anand
Published: December 2009

Mud Gas Isotope Logging (MGIL) is a gas fingerprinting technique that uses isotopic analyses of mud stream. The primary purpose of MGIL is to assess the extent of a reservoir and identify communication with any other formations. A Gas chromatograph is the main component used in MGIL. Although analysis using a GC will give amounts of methane, ethane, propane (paraffins); napthenes and aromatics are not explicitly analyzed. Also it is very difficult to distinguish between wet gas, condensate and oil using present day GC instrumentation. Another critical element is the speed at which readings can be taken with typical GC cycles of 3–6 minutes which may lead to thin zones not being traced at high ROP. It is not possible with GC based methods to distinguish compounds that exist as a free phase in the pore system from those that may be dissolved in an aqueous pore fluid since GC does not measure a wide range of Carbon species.

This paper proposes the use of Mass Spectrometry to analyze mud samples at wellsite. Samples can be analyzed to produce mass spectra of mass to charge ratio {MCR} across a range encompassing both abundant and trace inorganic and organic elements. MS holds a upper hand on GC because the latter does not provide chemical information, is comparatively slower compared to MS which gives real time results; and does not have baseline sensitivity to analyze fluid inclusions. MS also allows tracing of minute fractions of elements since MCR is unique for every element and compound. A further aspect of the paper is to create a chemical log which is a combination of species detected in the gas sample and species extracted from the mud system. Accordingly the chemical log can be used to influence drilling testing and well completion decisions. Some other applications of MGIL-MS include distinguishing between thermogenic & biogenic gas, monitoring H2S concentrations, identifying original fluid contact and CO2 flood breakthrough detection.
Taming the Grebe Sand – Tophole Drilling Success in the Ichthys Field
Authors: Hinton Andy , Eikemo Bernt , Tilley Vince , Nolan Tom
Published: December 2009

Drilling surface hole in Australia's Browse basin can be very difficult. The main problem is the massive, unconsolidated Grebe Sand which tends to collapse or slump into the hole. This often causes stuck drill pipe or casing. To achieve the well objectives on their recently completed Ichthys drilling campaign, INPEX implemented an aggressive well design with the 133/8" (340mm) surface casing set at 2500m (8200ft). There is no 20" (508mm) casing. The long, 2160m (7090ft), section 17–1/2" (444mm) and 16" (406mm) hole is drilled with mud and the Riserless Mud Recovery (RMR) system. This allows the mud to be circulated back to the rig and reduces the risks of hole problems. After some ROV problems, the RMR system was installed and the Grebe Sand was drilled without any hole problems. Below the Grebe formation, lost circulation problems were overcome. The open hole remained stable over four days of downtime (due to rig mechanical issues) before the 13–3/8" casing was run to the planned depth and cemented successfully.

The subsea pump ran without problems over 6 days at flow rates of up to 3800lpm (1000gpm). An estimated 5600mt or more of cuttings were pumped back to the rig with the mud. The primary well objective of setting the 13–3/8" surface casing at 2500m was achieved. The mud and RMR system also helped in curing other problems such as lost circulation. The system reduced risks of hole problems, such as hole collapse or stuck pipe. This resulted in a safer operation for the rig crew as well as a more economical well for the operator. An added benefit was the provision of cuttings samples over this interval for the geosciences department.
ZipLog—The Third Method for Well Intervention: Practical Field Experience and Unique Opportunities for the Future
Authors: Hansen Henning , Bakkevig Martha Kold , Kluth Richard
Published: December 2009

The E&P industry has up till today had two lightweight intervention methodologies for live production- and injection wells, being wireline or coiled tubing.

A third methodology, being the Ziebel ZipLog™ solution which is based on pushing a spoolable specially constructed carbon "rod" into live and pressurized wells, has been successfully developed and deployed into horizontal wellbores in the Middle East as well as North America.

This paper describes the background for the solution, the development and qualification program, the wellbore interventions performed and what the authors think the system can be further developed into.
Consecutive Dual Fracture Placement From One Location: Providing the Pinnacle Productivity From a Fracture Stimulated Wellbore
Authors: Surjaatmadja Jim B.
Published: December 2009

It is known that a fracture that is placed later in the life of a well will extend in a slightly different direction, mostly caused by the drainage of the fluid near the fracture face. In this situation, fracture redirection is most probably caused by the rapid pressure decline near the still-producing residual fracture face. Formation sharing between both fractures will not offer significant production increase.

This paper, instead, discusses fracture redirection created by another fracture created in a near similar time domain. It is believed that the first fracture will cause a substantial short term effect on the stress field, and in fact, redirect to a near-perpendicular direction. Combined with the hard-to-accept concept that fractures generally shy away from highly productive areas, this approach will cause the second fracture to extend directly into a direction that makes intersection with such high productive areas to be commonplace; thus providing substantial production boost.

In reality, the placement of a second fracture in the same wellbore in a similar locality and time span is quite difficult. The mouth of the fracture is generally unsupported, and therefore, the stress pattern at the wellbore face is generally returned to the pre-stimulation condition in a short time. Repressurization of the wellbore would then tend to reopen the first fracture. The hydrajet fracturing method is therefore proposed for placing the second fracture after a carefully precalculated (short) time delay, maximizing the temporary stress modification effect caused by the opening of the first fracture. The hydrajet technique will be used to exert the highest pressure at a location away from the wellbore and at an angular displacement of approximately 90 degrees from the first fracture, so that a new fracture can be initiated into a totally new direction. This can lead to a significant increase of revenue—cost ratio. In other words, a significant revenue increase can be obtained with just an incremental cost increase. Supporting simulation data are presented here.
Hydraulic Fracture Geometry Investigation for Successful Optimization of Fracture Modeling and Overall Development of Jurassic Formation in Western Siberia
Authors: Nikitin Alexey , Yudin Alexey , Latypov Ilyas , Haidar Azat , Borisov Gleb
Published: December 2009

The focus of our research is on a remote oilfield in western Siberia, currently in the initial stages of development. There are two producing horizons of Jurassic age with a shale barrier in between them and variable oil/water contact (OWC). Each new well of the field is a candidate for a hydraulic fracturing treatment. Depending on well location, there is an option to perform the fracturing treatment on the lower formation only, the upper formation only, or to conduct two separate fracturing operations. Fracture breakthrough on any of the jobs can lead to significant production underperformance.

With a goal to calibrate fracture modeling and identify the most critical parameters for fracture treatments, the decision was made to implement an independent measurement of frac geometry for an ongoing fracturing campaign. A total of 11 fracturing treatments are described in detail where differential cased-hole sonic anisotropy (DCHSA) measurements as well as bottomhole pressure gauges (BHPG) were implemented to enable precise modeling and to determine reliable fracture geometry. DCHSA, using a dipole shear sonic imager tools, allows for direct measurement of propped fracture height and fracture orientation azimuth. Provided with fracture height and using bottomhole pressure data, it was possible to accurately model resulting fracture half-length and propped width.

In addition to DCHSA measurements, a study to describe the geomechanical properties of the formations was also undertaken to further enhance the understanding of fracture height growth in the reservoirs. Advanced open-hole logging was performed on four wells, which served as the basis for creating a geomechanical model for other wells in the field. The methodology used to model stress distribution from acoustic logging was developed using a correlation created from density logs run on offset wells. This tool allowed for reliable fracture modeling at the design stage, and enabled optimization of fracture treatments.

By coupling the enhanced geological understanding obtained from the fracturing campaign with advanced geometry measurement technology, an effective geomechanical modeling method was successfully applied for future field development and production optimization. This research's technical workflow can be used as a comprehensive guideline in any field where precise placement of hydraulic fracture makes a significant difference in the overall development of a field.
Gravel Packing Long Openhole Intervals with Viscous Fluids Utilizing High Gravel Concentrations: Toe-to-Heel Packing without the Need for Alternate Flow Paths
Authors: Tolan M. , Tibbies R. J. , Alexander J. , Wassouf P. , Schafer L. , Parlar M.
Published: December 2009

Openhole gravel packing is one of the most popular completion techniques, due to its high reliability along with the ability to deliver high-productivity wells. Currently, there are two techniques used for gravel placement, one utilizing low-viscosity carrier fluids and low gravel concentration. In this technique the gravel is placed in two waves commonly called Alpha/Beta packing. The second method utilizes a viscous carrier fluid and high concentrations of gravel in conjunction with alternative path screens which mitigate problems caused by unpredicted downhole events.

In this paper we present a new approach for gravel packing long high angle openhole intervals without the need for alternative flow path screens but retaining the advantages of high gravel concentration slurries. This is supported by 2 field case histories from a field in India, where two gas wells were drilled with an oil-based drill-in fluid and gravel packed with a viscous water-based fluid. The packing mechanisms and efficiencies in these applications have been verified with downhole gauge analysis as well as mass balance calculations. Both wells are producing sand free with hydrocarbon production that met or exceeded operator expectations, with zero mechanical and extremely low rate dependent skins.
Key Issues and Operational Challenges in the Use of Dispersants
Authors: Quek Qiuhui
Published: December 2009

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

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

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

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

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

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

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

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

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

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

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

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.
Development of an Integrated Metrics Reporting Tool to Monitor and Optimize Performance of the Greater Burgan Oil Field in Kuwait
Authors: Desai Sameer F. , Abdulla Farida , Gazi Naz H.
Published: December 2009

Greater Burgan is the second largest oil field and the largest clastic reservoir in the world. There are over 1000 wells on production in this field. There is a robust plan to drill more wells in the coming years to cater for world demand in production. It is therefore necessary to track and report the production and field performance from this giant field in a timely and effective manner. This paper describes the approach taken towards the development of an integrated tracking and reporting metrics tool which displays operational data to key decision makers to monitor field performance and make practical decisions.

The metrics report provides a comprehensive view of the performance of an asset using key performance indicators (KPIs) in the form of a dashboard. Information is captured from corporate databases, in house tools and data sources tracking daily operations. The report is displayed graphically for quick overview of categories such as daily production, subsurface and shut-in well potential, facility capacity and constraints, well work, production tests, surveillance activities, wet and dry completions, production allowables, and other pertinent highlights through a single visual interface.

Designed as a scorecard the tool provides a platform for increased collaboration and knowledge capture between assets. It reduces time spent looking for data thereby allowing more time for higher priority issues. The impact is directly on the reservoir management strategies, production management, prioritization of well work and surveillance activity.

The metrics report is a best practice implemented by KOC Field Development South East Kuwait Asset Group to monitor the Greater Burgan oil field performance and optimize its production. Value added decision making is made easy wherein plans are properly implemented and targets are met. The designing, completing, and operating aspects of this successful reporting tool are highlighted together with the challenges and accomplishments.
Integrated Solutions for LNG Plants System Studies: Simultaneous Simulation of Electrical and Steam Systems
Authors: Lerch Edwin , Fehn Thomas , La Seta Piergiovanni , Tomschi Ulrich
Published: December 2009

In the last decades the importance of LNG (liquid natural gas) has been increasing continuously. Worldwide a large number of plants have been erected using classical compressor technology driven by direct-coupled gas turbines. This approach limits the availability due to maintenance restrictions and the missing spinning redundancy. Modern concepts are based on large full electrical compressors which allow controlling the process with reduced energy consumption. The corresponding maintenance concept improves the LNG plant availability significantly.

LNG plants generally have no grid connection, i.e. the LNG plant must be supplied under island conditions. Guarantee a high availability of the electrical and steam generation is however necessary. Therefore it is primarily important not only to provide a suitable system design, but also to investigate its ability to dynamically withstand heavy events, taking into account the mutual interaction of electrical output of the steam turbine and the variation of the steam demand, the boiler capacity and the dynamics of the supplementary firing.

Aim of this paper is to illustrate an integrated approach for the steady-state and dynamic study of LNG plants, in which both the electrical and the steam system are completely modeled and interfaced. After separate design, both systems are simulated with the same simulation tool, so operations and events are immediately incorporated and the two systems show the reciprocal interaction. Thus more realistic and significant system responses to events are obtained, with increase in the project efficiency and reduction of investment costs.

To validate the approach, a typical LNG plant is modeled, including all relevant equipment and controllers, as well as process system units, with PSS®NETOMAC. The simulation of severe outage cases allows to optimize the basic electrical and steam control concept and to design the load or generation shedding sequences, depending on the outage severity.
Bioremediation of Crude Oil Contaminated Soil by Composting using Wood Shaving as Bulking Agent
Authors: Ahiamadu Nnamdi Michael , Suripno S.
Published: December 2009

Oil exploration and production activities can cause severe environmental damage due to crude oil discharges to the environment. Remediation of impacted environment follow a general framework hinged on legal/regulatory framework and site specific risk assessment of the levels of contaminants present. Within this general framework of regulations, site specific constraints and cost-effectiveness, the best available technique (BAT) for remedial actions is usually proffered. In this study case of crude oil contaminated soil remediation, composting of the contaminated soil in bio-piles using wood shavings (saw dust) as bulking agent and a commercial product as source of both commercial microbial inoculums and nutrient (N, P, K), was adopted. The major activities in this project involved composting in windrows, broadcasting of the nutrient source and laboratory monitoring. The Total Petroleum Hydrocarbon (TPH) degradation was most rapid during the first 5 weeks of the remedial activities and thereafter followed a typical first order degradation curve. After, 22 weeks of treatment 93% from 3830mg/kg dry weight to 268.1mg/kg dry weight degradation of TPH of the contaminated soil was achieved and a corresponding increase in number of bacterial populations was also observed.
Rapid Prediction of Carbon Dioxide Adsorption Isotherms for Molecular Sieves Using Simple Correlation
Authors: Bahadori A. , Vuthaluru H. B.
Published: December 2009

CO2 emission from burning fossil fuels has been identified as the major contributor to the increase in atmospheric CO2 levels that can potentially lead to global climate changes. Among main methods that are being developed for CO2 capture and separation, carbon dioxide adsorption is of great interest due to its low energy consumption, low equipment cost and easiness for application. In this work, a new simple-to-use correlation, which is easier than current available models involving a large number of parameters, requiring more complicated and longer computations, is presented to predict accurately the carbon dioxide adsorption isotherms for a molecular sieve as a function of temperature and carbon dioxide partial pressure. This correlation predicts the carbon dioxide adsorption isotherms for carbon dioxide partial pressures and temperatures up to 120 kPa and 470 K respectively. The promising method to develop correlation for accurate prediction of carbon dioxide adsorption isotherms could be extended for CO2 capture and separation for the wide range of adsorbents including various molecular sieves just by readjusting the tuned coefficients. The average absolute deviation between reported data and the proposed correlation is around 4%. Simple-to-use approach can be of immense practical value for the Engineers and Scientists to have a quick check on adsorption capacities of a given adsorbent at various temperatures and pressures without performing any experimental measurements. In particular, personnel dealing with regulatory bodies of greenhouse gas abatement, process industries would find the proposed approach to be user friendly involving no complex expressions with transparent calculations
Subsea Separation and Boosting—An Overview of Ongoing Projects
Authors: Gruehagen Henning , Lim Dennis
Published: December 2009

Subsea processing is one of the most interesting technologies currently being introduced into the oil and gas industry. Treating the production flow at the seabed opens up opportunities to achieve more effective deployment of oil and gas reservoirs in all regions around the world. Among these are Tordis in the North Sea, BC-10 in Brazil, Perdido in the Gulf of Mexico and Pazflor in Angola. All of these projects include subsea separation and boosting.

For BC-10 and Perdido, gas/liquid Caisson separators with a length of approx. 100 metres are utilized together with Electrical Submersible Pumps (ESPs) to enable and boost production from deep water reservoirs.

The Tordis Increased Oil Recovery project realizes the first commercial full scale subsea separation installation in the world. By separating out water and sand at the sea floor and injecting this waste into a dump reservoir in a closed loop system.

The successful installation and start-up of the Tordis Subsea Separation Boosting and Injection system and the Perdido gas/liquid Caisson separators, subsea processing is now taking its first steps into the future.

The common view is that there will be many applications for subsea processing as the technology matures and gather more widespread acceptance. With the oil industry running out of oil that is easy to produce, means that producing oil and gas from offshore fields in deeper waters and in more remote areas is inevitable.

Considerable efforts are being made in the area of subsea gas compression, which has great potential and could save cost of additional surface infrastructure where compression is needed to continue production of maturing gas and longer step-out fields.

Although the solutions for these projects are different, many of the technological challenges are similar. A brief overview of the technological challenges for these projects will be presented, together with recent developments within Subsea Processing.
Utilizing UBD Technology for Future Development of Parsi Oilfield, Challenges and Opportunities
Authors: shadravan Arash , Nabaei Mohammad , Amani Mahmood
Published: December 2009

Underbalanced drilling is considered as one of the main recommended technologies for further development of Iranian depleted fractured carbonate reservoirs. Parsi is one of the most depleted oil fields located in south western part of Iran which started to produce with initial pressure of 3,800 psia in 1966. In 2001 the reservoir pressure was 3,000 psia with 1.48 Billion STB cumulative production. By June 2009 some1.68 Billion STB had been produced with the current reservoir pressure of 2,470 psia at 1,800 meters subsea. The serious challenge in this field is dealing with the complete losses in drilling operation. Also high production rate has increased GOR and caused gas coning. National Iranian Oil Company (NIOC) has initiated UBD technology program since 2005 in southern Iranian depleted fields. The key aspects for utilizing UBD in Parsi oilfield have been: avoiding complete losses and reservoir impairment, improving rate of penetration (ROP), drilling performance and reservoir fracture productivity. This paper evaluates the advantages of UBD in Parsi oilfield and summarizes practical solutions not only to overcome the challenges happened during the UBD implementation but also to gain more financial returns in drilling a well in this field. Data and experiences of OBD and UBD wells in Parsi field have been used as a basis for this study.
Seismic EOR—The Optimization of Aging Waterflood Reservoirs
Authors: Kurawle Irfan , Kaul Mohit , Mahalle Nakul , Carvalho Vickey , Nath Neelendra , Amin Zohaib
Published: December 2009

The majority of enhanced oil recovery projects currently underway are based on Water floods which are known to provide lesser recovery compared to other recovery mechanisms. Many such reservoirs exist where the recovery has been less than 30% altogether due to various drawbacks of the conventional Water floods. The paper would like to discuss a new EOR technique using Acoustic and Seismic energy to reduce interfacial tension and promote coalescence of oil ganglia using the resonant frequency principle. The technique uses pressure and sound waves at pre-determined frequencies to set the oil molecules in motion to promote coalescence and thus reducing the fingering effects. The flood pattern can be optimized by recovering oil from previously unswept areas. It thus enhances the life of the primary flood providing valuable economic savings. The process can also be applied to various reservoirs in their tertiary recovery phase to extend the life of the project. Experiments conducted in the lab show that the frequency of oil and water may differ from reservoir to reservoir and compositional analysis of samples is required to determine the resonating frequency. The design of the downhole tools for injector wells to implement this technique are also discussed briefly.