bluuebunny/crossref_metadata_2025_split huggingface dataset:
Underbalanced Perforation and Completion of a Long Horizontal Well: A Case History
Authors: Bowling J. , Khan M. , Mansell M. , Balushi H. , Somat E. 
Published: December 2007

Abstract
A clastic reservoir in central Oman is to be developed with some 100 wells. The rock is sensitive to formation damage and experience shows that productivity is improved by a factor of 10 by perforating with deep-penetrating charges underbalanced and avoiding contact of brine with the formation. The wells will be horizontal to drain a 24.5m oil rim, and zonal isolation for future water and gas shutoff is desirable.
An interval of 600 meters was perforated with 4 ½" OD guns. The guns were retrieved under pressure and a lower completion packer was run to isolate the reservoir from the surface. The upper completion was run with crude in the hole to ensure that no brine should contact the formation.
To perforate underbalanced with a drilling rig, the well was constructed with a 7" liner at the start of the build section to total depth of the well. A 7" tie-back was run with a surface controlled downhole isolation valve (DHIV) as a barrier after perforating. The well was displaced to crude to create underbalance. A 7" predrilled liner joint was run beneath the DHIV in the work string to allow circulating out well bore fluids so that the guns could be retrieved safely. A rotating control head and underbalanced drilling surface equipment package was utilized for stripping with 8,000 kPa surface pressure bleed off volumes for tripping and manage the crude circulating system. The tie-back was retrieved and the upper completion was run after setting a plugged packer in the 7" liner. This method is unique because it utilized a conventional drilling rig for completion operations along with an underbalanced drilling package to perforate and complete the well underbalanced.
Parametric Analysis of MPD Hydraulics
Authors: Tian Shifeng , Medley George , Stone C. Rick 
Published: December 2007

Abstract
Managed pressure drilling is a process that utilizes friction pressure and annular back-pressure in addition to conventional hydrostatic column pressure to allow drilling of difficult formations. There are many parameters that play a part in the managing of wellbore pressure during fluid flow. Wellbore pressures are impacted by fluid density and rheologic properties, injection rates, cuttings transport, influx while drilling, wellhead or choke pressure, hole geometry and drillstring configuration. The effects of these parameters on wellbore pressure are different, but interact with one another. Therefore, careful consideration is needed when choosing which parameter(s) should be adjusted to manage the wellbore pressure during any particular operation.
A good understanding of the effects of these operating parameters on wellbore pressure is essential in the optimum design of an MPD project. This is especially true of the rheologic properties of MPD fluids. Rheologic properties of drilling fluids play important roles in the variation of wellbore pressure during any MPD operation. Most drilling fluids (WBM, SBM, or OBM) currently used in the field have a nonzero yield point (YP). A non-zero YP causes a sudden bottom hole pressure (BHP) jump when fluid starts to move or when fluid is about to stop moving. It also causes a sudden BHP jump when the drillstring starts to move up or down during tripping or connections regardless of how slow the pipe moves. The sudden pressure jump makes it difficult to minimize BHP variations.
This paper discusses the effects of various operating parameters on wellbore pressure and provides guidelines for managing wellbore pressure by adjusting those operating parameters. A simple equation to predict the sudden pressure jump caused by YP is provided. Field cases are used to illustrate managing wellbore pressure by adjusting various operating parameters.
Air Drilling in the Presence of Hydrocarbons: A Time for Pause
Authors: Malloy Kenneth P. , Medley George H. , Stone C. Rick 
Published: December 2007

Abstract
Drilling with compressed air continues to enjoy vast popularity. It is often the application of choice in dry, hard rock because the drilling fluid medium is inexpensive and, compared to water or weighted drilling mud, respectable rates of penetration can be achieved. In terms of economic considerations with respect to drilling fluid expenditures, air drilling has virtually no equal. However air drilling is not without its impediments; not the least of which is its reactivity with hydrocarbons.
Learnings from Implementing the Occupational Hygiene Program in Chevron Thailand
Authors: Rungruang Surapat 
Published: December 2007

Abstract
The Chevron Thailand Industrial Hygiene Monitoring Program has been developed and implemented since mid-1980’s with the aim to comply with both the recognized standards and local regulations, but more importantly to protect the health of all workforce while working with the company.
During this 26-year period of industrial hygiene program implementation, significant numbers of industrial hygiene samplings have been taken from different workforce group in a vieriety of locations.
Over the past years, many baseline sampling and monitoring initiatives have been conducted to identify specific problem areas. The monitoring strategy, health risk mitigations and controls were based on the numbers of samples colleced during that period. During the early 90’s an annual industrial hygiene monitoring plan were developed and issued prior to identifying and qualtifying job specific hazard exposure.
Assessing the Potential Production of a Tidal Current Energy Project
Authors: Ruer Jacques 
Published: December 2007

Abstract
The renewable resource of tidal current is presently attracting the interest of many companies. Several systems are in the development stage and SAIPEM is participating in one of them.
The tidal streams are predictable well in advance but are variable along the hours and the days. In order to determine how much energy can be produced during a year, a model has been written. It takes into account the local current characteristics and the astronomical evolution of the tide during a whole year. This model indicates how to select the nominal electrical capacity of the tidal turbine in order to optimize the energy cost of the scheme. The model teaches that a turbine located in a tidal race off the European coast has an equivalent number of producing hours of about 3000h per year as an average.
In some locations, the site may be exposed to the swell in addition to the tidal currents. A tidal current turbine reacts almost instantaneously to the velocity variations, because the inertia of the turbine is small compared to the inertia of the water flow crossing the rotor. This results in power fluctuations of a single turbine, at least as long as the water velocity does not exceeds the nominal rating of the machine. Some examples are shown to illustrate the different cases. The local wave climate should be taken into account in order to correct the yearly production on a statistical basis. The potential influence of a strong swell may alter the maximum power predicted based on the sole astronomical parameters.
Clusters of tidal turbines have also been studied. The detrimental influence of the swell can be mitigated through an optimum design of the turbine array. When the current is slow and the swell important, the cluster can even produce more energy than without the waves.
Enhanced-Oil-Recovery Potential of Heavy-Oil Fields in Africa
Authors: Yee Hon Vai , Kechut Nor Idah , Razak Wan Nurul Adyani W 
Published: December 2007

Abstract
This paper presents an enhanced oil recovery (EOR) evaluation for two heavy-oil fields in Africa. The objective of the evaluation is to identify the technically and economically viable EOR techniques for the fields. A total of thirteen established and emerging EOR techniques were evaluated in this study. The study included the first degree approximation of the oil recovery for the viable EOR techniques and the stand-alone project economics estimation.
The data required for the study include: 1) fluids and rock properties; 2) driving mechanism; 3) production data; 4) OOIP and recoverable reserves; and 5) relative permeability curves. Various EOR technique screening criteria, consisting of a list of reservoir parameters and their ranges which are likely to lead to a success, were applied to match the parameters of the study fields. The oil recovery predictions were estimated utilizing general reservoir parameters and developed correlations1. The economic feasibility of the potential EOR techniques was then evaluated based on the stand-alone project economics that accounted for the revenue from the incremental oil and the associated operating and capital costs.
The evaluation results showed that the thermal EOR techniques: steam flooding and in-situ combustion are technically the most viable EOR techniques for the fields. It was then followed by the chemical EOR techniques. The performances of steam flooding and in-situ combustion are both very promising, with oil recovery of up to 49% OOIP. Comparing to the oil recovery of water flooding, a significant incremental oil recovery of 24% OOIP was obtained. However, the in-situ combustion process is able to accelerate the oil production, which significantly impacts the economic viability assessment, rendering the in-situ combustion process as the most technically, and economically feasible EOR process for the fields.
Based on the EOR evaluation, the oil recovery predictions and economic assessments of the thirteen EOR techniques, including the chemical, gas, thermal and microbial EOR techniques, served as a guideline to develop the long term corporate strategy regarding the EOR potential of the fields.
Spreadsheet Simulators that Demonstrate how Statistics can Lie about Safety Performance
Authors: Veley Carl 
Published: December 2007

Abstract
The science of statistical analysis uses advanced mathematics beyond the capabilities of most people, but the principles behind those high level equations are essential in understanding the role of chance in conventional safety performance metrics. A series of spreadsheets has been developed to illustrate some of the essential principles, without utilizing the daunting rigorous mathematical proofs. Readers who experiment with these spreadsheet simulators may be surprised to find some of their routine or basic assumptions about safety statistics are actually scientifically indefensible. Studying the principles illustrated by these simulators may suggest needed modifications to common industrial safety programs.
The Growth of Online Oil in Water Monitoring and Statoil's Experience on the Sleipner A Platform
Authors: Aanensen Geir 
Published: December 2007

Abstract
The increase in produced water has led to a growing need from E&P operators for better oil in water monitoring systems. Roxar has developed an inline and online oil-in-water monitor suitable for topside discharge and re-injection applications, based on ultrasonic technology.
The first Roxar Oil-in-water monitor was installed in May 2006 on Statoil's Sleipner A platform in the North Sea. Statoil is using the monitor to measure overboard water discharge, ensuring that it meets environmental requirements and efficiently monitors the separation process.
Immediately after installation, attempts were made to introduce increasing amounts of oil into the produced water stream to verify that the monitor registered oil concentration changes accordingly, which it did. Periods with distinctly higher concentration levels were also analyzed. The rapid change in water level in the separators corresponded to an increase in the oil-in-water concentration downstream. During the trial phase, reliability and robustness have been demonstrated, and this paper describes how the ultrasonic measurement techniques, combined with a novel reflector design, helps the operator obtain accurate oil concentration readings even during and after experiencing production instability.
This paper presents results from the pilot, verifying the performance of online oil in water monitoring and its ability to operate at different concentrations.
The pilot to date has confirmed the monitor's ability to provide accurate information to Statoil on the size distribution and concentration of oil and is already playing a key role in monitoring Statoil's overboard discharge and separation process.
Occupational Illness: Challenges Faced
Authors: Kumar Surya 
Published: December 2007

Abstract

What is Occupational Health?
A simple definition of health is as follows: "a state of physical, mental and spiritual well-being". Occupational health is a state of such well-being at the workplace. Occupational health comprises three main components. They include occupational illnesses, illnesses that can be affected by factors at the workplace and illnesses that are unlikely to be affected by the workplace. Examples of occupational illnesses include lead poisoning, asbestosis and noise-induced deafness. Illnesses that may be affected by workplace factors include asthma and some liver diseases, depending on exposures in the working environment. Although technically possible in some cases, many medical conditions are not usually affected by factors within most workplaces. These include lifestyle-associated and hereditary diseases such as diabetes and high blood pressure.

Health Determinants
What determines your health? Firstly, one’s genes or who you are play a very important role. A family history of certain illnesses enables us to predict one’s risk of certain diseases such as diabetes and high blood pressure and cancers such as breast and cervical cancer. Secondly, one’s lifestyle and habits such as diet, exercise and smoking do, of, course change your risk for certain lifestyle-associated diseases. Health promotion takes care of this element. Thirdly, factors in the environment, including the work environment, can determine one’s health as well. We need to protect individuals, including the worker, from these adverse factors.

Occupational Health
Occupational Health involves predicting vulnerabilities, promoting good health and protecting the workforce. Exposure levels of many substances in the workplace can be much higher than those in general environment. Occupational health deserves more focus because ill-health effects may not manifest for a long period of time. The Health Risk Assessment identifies, evaluates and seek ways to control the impact of occupational risks on the worker; hence preventing illnesses that can be acquired through such direct workplace exposures. A responsible company goes beyond occupational health to promote general health and well-being.
Systematic Investigation of Waterflood Reducing Residual Oil Saturations by Increasing Differential Pressures at Various Wettabilities
Authors: Johannesen Else B. , Graue Arne 
Published: December 2007

Abstract
The ratio between the viscous and capillary forces, commonly denoted the Capillary Number Nc, is crucial in determining the remaining oil saturation. The impact on residual oil saturation by a systematic increase in Nc is determined in homogeneous chalk at wettabilities varying from nearly neutral-wet to strongly-water-wet conditions. In fractured chalk reservoirs waterflood residual oil saturation is strongly dependent on the wettability. The current results provide assistance in determining the potential target for tertiary oil recovery by measuring the amount of mobile oil at various Nc. A series of displacements of oil by water injection at increasing constant pressures were carried out to determine the relation between remaining oil and applied capillary number in waterfloods at different wettability conditions.
Various uniform distributed mixed wettability conditions were established and quantified by the Amott test for 21 core plug samples. Minimum remaining oil at constant Nc occurred at wettability conditions reflecting an Amott Index to water at 0.3. The residual oil saturation decreased with increasing capillary number and significant trapped oil after completed spontaneous water imbibition was mobilized at moderately water-wet to nearly neutral-wet conditions. Similar results as reported in the literature for waterflooding residual oil saturations as function of wettability and PV water injected in sandstone were found for chalk at increasing capillary number. Distinct dome shaped curves of oil recovery as function of wettability, with consistent increase in oil recovery with increasing capillary number, reflected similarities to earlier results on waterflooding oil recovery.
The Development of an Artificial Neural Network as a Pressure Transient Analysis Tool for Applications in Double-Porosity Reservoirs
Authors: Alajmi M. , Ertekin T. 
Published: December 2007

Abstract
Naturally fractured reservoirs have been studied extensively in the past decades. These reservoirs consist of two distinct porous media: the macropores and the micropores. Several analytical models have been suggested to characterize such reservoirs. In this work, one of the proposed double-porosity pressure transient models is adopted in the description of the naturally fractured reservoirs. The forward solution component of the analytical model is used to generate the pressure transient data, given the characteristic parameters of the double-porosity reservoirs. The double-porosity systems are characterized by a pressure transient signature which is composed of two semi-log straight lines connected by a transitional curve. The pressure transient responses obtained by the analytical forward solution are subjected to a polynomial fit algorithm so that the aforementioned double-porosity signature can be represented by five polynomial coefficients. These coefficients, the known properties of the double-porosity reservoir, and the reservoir fluid and well parameters constitute the principal input given to the artificial neural network (ANN) during the training phase. The ANN, then, inversely predicts the desired unknown properties of the double-porosity system, namely the permeability of the fracture, the porosity of the matrix, the porosity of the fracture, and the permeability of the matrix. This final development of the ANN is achieved by utilizing this inverse protocol in gradually increasing levels of complexity. The complexity of the problem is elevated by increasing the number of unknown characteristics of the double-porosity system. This research demonstrates the efficiency of the ANN utilization in obtaining the desired properties of the double-porosity reservoirs.
Development of a Security Process To Meet the Requirements of Oil and Gas Companies in the Asia Pacific Region
Authors: Quin Matthew 
Published: December 2007

Abstract
Security risks are behind some of the most pressing risk management concerns of oil and gas companies in the Asia Pacific region. However, the effective management of security risks is generally not well understood by business managers at all levels.
There is a strong requirement to develop a standard process that allows oil and gas companies to both manage security risks and meet their business requirements in the various countries in which thy operate. The process, once developed, needs to be integrated into all relevant aspects of the business.
This paper will explain how this modern Security Process is developed.
The Security Process should be developed as a core feature of a company’s operations management system, allowing all levels of the organization to understand how the management of security fits into the business structure.
This provides legitimacy of the security process throughout the company and promotes its integration with other relevant aspects of the business, thus providing critical links with other core functions such as safety and crisis management.
Having a Security Process as an integral part of a company’s management system leads to greater accountability and awareness of security at all levels of management. This in turn leads to a more cost effective allocation of resources, greater accountability of the security function and a better overall understanding of how to protect the company’s people and assets.
Integrated Quality, Occupational Health, Safety, and Environment Management System in ONGC—A Pursuit for Excellence
Authors: Roy Badal 
Published: December 2007

Abstract
Effective Management of Quality, Occupational Health, Safety, and Environment (QHSE) is not only a regulatory and ethical issue; there are also sound economic reasons for it. ONGC is a company involved in the complete chain of hydrocarbon business from exploration to marketing. As a major player in the global competitive market, ONGC has always recognized its responsibility towards effective management of QHSE in the organization.
In the year 2002, Neelam & Heera Asset in the Western Offshore field came up with a unique innovation. They realized that the control of all three aspects is done principally by the same management principles and integration of these aspects in an overall management system could be highly efficient and effective and may lead to synergy. Moreover, acquiring simultaneous certifications will also result in a substantial saving in time, effort and money. Based on this conviction, an integrated QHSE management system was developed and adopted for the first time by the Asset. The commitment of ONGC management to get the organization to the level of the best in the industry spurred it to take a significant decision. It was decided that all the operations of ONGC would acquire certification for integrated QHSE management system by March, 2005. The task was daunting but the success would catapult the organization in the midst of the best in business, as no organization had attempted such a move till then.
More than 400 installations spread all over India both offshore and onshore were taken up for certification. It was decided to use in house expertise instead of external consultants for the job as it was felt that persons with knowledge and experience about the organization’s working can save on time. By 31st March, 2005 more than 98% of the total work centers of ONGC succeeded in getting certified for integrated QHSE management system. The commitment of the employees from all over the organization to the new system was underlined with all the certified work centers successfully going through the surveillance audit in the following year.
Implementation of the integrated QHSE management system in totality is a major step by ONGC towards an era of safe, responsible and quality work culture. This will make all the individuals aware about their responsibility towards themselves, the organization and the society at large and benefit the organization enormously in business and social acceptance.