bluuebunny/crossref_metadata_2025 huggingface dataset:
Reducing the Learning Curve Through the Use of an Advanced Drilling Simulator
Authors: Hodgson R. , Hassard P.
Published: December 2007

This paper describes how the use of a full size, real time, drilling simulator is proving to significantly reduce the learning curve for drilling operations.

Traditionally simulators have been used for well control training, or the training of crews to operate new generation automated drilling equipment. Modern drilling simulators are, however, also now being exploited by performance oriented teams to practice techniques and procedures in a risk free, low cost environment.

Techniques such as Through Tubing Rotary Drilling (TTRD) and Extended Reach Drilling (ERD) are now routine techniques for many Operators. However, these operations are still typically new to many of the field drillcrews involved. The paper describes how state of the art simulators are being used to realistically model the proposed operation placing emphasis on anticipated well challenges.

An explanation is given as to how well planners can identify whether certain aspects of their programmes are effective and then establish whether all anticipated eventualities have been covered, allowing time for procedures to be modified and contingency plans to be prepared well in advance of actual operations commencing. Rig teams can be observed proactively addressing the information coming from the well and how they react to problems, allowing supervisory personnel to identify gaps in understanding or training which need to be addressed in order to give both Operators and the Drilling Contractor greater confidence in "getting it right first time".

The paper concludes that the use of such facilities can significantly accelerate the learning experience when developing innovative well programmes, when embarking on challenging well operations, or even to ensure trouble free start-ups for new rigs and crews.
Ranking Geostatistical Realizations by Measures of Connectivity
Authors: McLennan J. A. , Deutsch C. V.
Published: December 2007

Geostatistical reservoir modeling provides multiple equally probable realizations of structure, facies, and petrophysical properties. A large number of realizations should be processed to ensure that production decisions and strategies are not unduly affected by an unusually good or bad simulated realization. Flow simulation, however, often requires significant computational and professional time. Only a few geostatistical realizations can be subjected to detailed flow modeling. An integrated approach is developed for ranking geostatistical realizations. A small number of representative realizations can then be selected for flow processing.

The ranking and selecting of realizations must be tailored to the flow process. Techniques that work for conventional oil and gas reservoirs are not necessarily suitable for in-situ and SAGD bitumen recovery methods. This paper describes static connectivity measures tailored to heavy oil recovery processes from the McMurray Formation. Flow simulation is performed on many geostatistical realizations to calibrate the ranking measures to production response. This permits reliable inference in reservoir areas where it is not possible to perform many flow simulations.
Environmental, Social, and Health Impact Assessment (ESHIA) Process
Authors: McHugh S. , Maruca S. , Lilien J. , Manning A.
Published: December 2007

The Chevron International Exploration & Production's (CIEP's) integrated Environmental, Social, and Health Impact Assessment (ESHIA) process is described together with the results of its implementation. The value added by an integrated approach to environmental, social, and health impact assessments is discussed. The key features of the process are the requirement for projects to be screened early in project development, stakeholder engagement to be conducted, and management plans to be developed for the construction and operations phases. The details of the process and its governance are addressed.

ESHIA requires multi-disciplinary teams to evaluate environmental, social, and health impacts and risks. The clear expectations on social impact assessment and stakeholder engagement have generated high value cooperation between HES and public affairs specialists. The early identification of potential impacts has greatly improved the quality of project decision-making.

ESHIA is critical to oil and gas companies who wish to access new opportunities, obtain external financing, acquire licenses to operate, deliver sustainable development, and enhance company reputation. In many areas of the world, there is little regulatory or cultural distinction between environmental, social, and health impacts. Stakeholder engagement is an increasingly important project requirement with increased expectations from governments and lending institutions. The integration of these factors into project decision-making is a key success factor to the delivery of long term project value.
Security Matrix in the Niger Delta Operations
Authors: Inyang E. , Oyinlola S.
Published: December 2007

Schlumberger operations in Nigeria significantly fall under the Niger Delta area.

This area is continously subject to threat occasioned by a precarious security situation and the associated risk levels are continously evolving. It is therefore necessary that this risk be constantly monitored such that the exposure is controlled and always mentained at an acceptable level.

The objective of this project is to identify the hazards associated with each area and develop a Risk Matrix, which will be used to constantly assess the likelihood and severity of these risks and hence provide detailed preventive and mitigation measures to reduce this risk to a level which is as low as reasonably possible (ALARP).

In order to monitor this evolving risk, an assessment of the communities where Schlumberger has active operations or could possibly have in the future was carried out. Harzards such as violence, mugging, injury, theft, blackmail, extortion, threats, kidnapping, revolution, civil war, expropriation, loss of control over operations, occupation of or damage to Schlumberger facilities, etc were identified. Possible sources of the identified hazards such as political extremists, terrorists, insurgent groups, hostile military and paramilitary forces, petty criminals, organised criminals, computer hackers, protesters, striking workforces, indigenous groups, corrupt officials, dishonest business partners, and disloyal employees were also identified.

The communities in the Niger Delta were then categorized into different risk zones (including black, Red, Yellow, Green and Blue) with respect to the hazards identified therein.

A Risk Matrix was then developed to measure the likelihood and severity of these risks.

The necessary requirements for prevention and mitigation were established in addition to an Emergency Response Plan.

Security porcesses were established for operation in different areas according to their risk zones.

Exemption processes including the authorizing signatories for the exemption were also defined both for the Client and Schlumberger.

This Project was implemented in one of the Niger Delta Fields (the Soku field of SPDC) with success.
e-Med File: A Toll To Strengthen Occupational Health Programs
Authors: Celly J. J. Z.
Published: December 2007

In this article, e-Med File (EMF) refers to a software that allows entering medical data (from petroleum industry employees) to make critical medical information available for further reference and consultation for the employee and authorized doctors anywhere an Internet connection is accessible.

Also some statistical information could be presented for managers or supervisors, for planning and resource allocation purposes, for example.

In the petroleum business—especially in oilfield operations—the capacity for adequate medical response in case of common medical problems or life-threatening emergencies is critical, because the working conditions and extreme environments make very difficult—and often impossible—immediate and "proper" medical care, so quick access to vital information could save lives.

On the other hand, mobility is usually a characteristic of petroleum employees, where the employee may travel within a country, a continent, or worldwide. In various areas, medical technology might not be appropriate and thus some medical information requiring certain types of technology might be impossible to obtain. With electronic storage, medical data "travels" with the employee everywhere.

Also, some applications are recommended to make the software a useful tool in occupational health programs:

Allows locals doctors to extend medical certifications for legal purposes, based on reliable medical records. Alarm (or high values) laboratory results of an employee are electronically informed to the employee and to key health personnel for further investigation or action. Follows-up for planned physicals or health controls (for example referrals or additional clinical or laboratory investigation). Informs in advance about expiring dates of physicals and medical check-ups. Allows doctors and/or managers to obtain statistical information to present reports for multiple purposes.

In this context e-Med Files could play an important role to increase performance of petroleum companies in medical emergencies and occupational health programs.
Introduction of New Drilling Technology Improves Performance of Mature North Sea Assets
Authors: Anderson J. , Niescierowicz G. , Ruszka J. , Blair J. , Connell S. , Omokwald A.
Published: December 2007

The Central North Sea (CNS) Cretaceous formations are notoriously difficult for performing directional drilling operations. Oriented drilling using bent housing steerable motors is troublesome and rate of penetration is unacceptably slow with rotary steerable systems. This has historically resulted in well trajectories being planned with minimal directional course changes through these sequences and, when directional course changes are absolutely required, oil based mud is often required to facilitate oriented drilling. With many assets in the Central North Sea reaching maturity, directional drilling course changes in the Cretaceous has increasingly become a necessity to access remaining targets.

Talisman Energy (UK) Limited acquired several CNS mature assets in the period 1997 – 2005. A challenge faced by the operator was to improve directional drilling control and overall drilling performance through the CNS Cretaceous while simultaneously moving away from oil based mud requirements. A new generation rotary steerable system which integrates a performance drilling motor with a high speed rotary steerable tool was introduced to meet this challenge. By applying this new system coupled with the latest steerable drill bit technology, precise three dimensional trajectories are now being drilled at more than double the offset rates of penetration & water based mud can now be used more frequently. The results have been easier access to remaining reserves, a dramatic reduction in drilling time, lower environmental impact and overall reduced cost and risk.

This paper describes the drilling conditions in the CNS and the new drilling technology applied. It also describes the challenges encountered applying new technology on cost sensitive mature assets, procedures put in place to minimise operational risk while introducing the new system and a comparison of performance now compared with that of offset wells.
The What and How for HSE Management Systems
Authors: Weldon D. , Wallace J.
Published: December 2007

This paper provides an overview of the approach used in ExxonMobil Production Company (EMPC) to implement and execute HSE management systems. The systematic approach to managing health, safety, environmental, and security risks in ExxonMobil is referred to as Operations Integrity Management System (OIMS). The Corporate OIMS Framework includes 11 Elements and 64 Expectations, the characteristics of a management system, and how to evaluate management systems. EMPC has defined and documented 24 management systems that are standard among all producing business units to address the OIMS requirements. The concept of EMPC's management systems is described in the paper and ranges from the driver system (Management Leadership and Commitment) through operations-related systems to the system for evaluation (OIMS Assessments). Each management system document is intended for use by a system owner and administrator and describes ‘What to do’. The system owner and administrator are responsible for developing the processes and procedures required by the system, and they can reference successful work practices for procedure development. The system processes and procedures are the ‘How to do it’ portion of the system. System owners and administrators use the system documentation ‘What and How’ to develop appropriate training, to roll out the system to end users, and to assist the business unit with system execution.

This paper provides HSE management system implementation guidance that has been gained from executing OIMS for over a decade and includes recent system upgrades so that operating sites can implement more effectively. The improved performance from using OIMS is also demonstrated in the paper.
Accelerating Technology Acceptance: Hypotheses and Remedies for Risk-Averse Behavior in Technology Acceptance
Authors: Rao V. , Rodriguez R.
Published: December 2007

Risk aversion was concluded as being a significant factor in the observed slow uptake of technology in the Upstream Sector of the Oil and Gas business. Hypotheses centered on information asymmetry, effect of risk volatility on tolerance, and risk profiles of decision makers molded by structural or temporal considerations. Remedies proposed for debate and action included the creation of industry wide independent entities (testing agency or insurance company) charged with closing the gap created by asymmetries, as well as the creation of an industry award for excellence in technology uptake.
Managerial Resilience and Safety: Vasa to NASA
Authors: Flin R.
Published: December 2007

Organisational resilience is a new concept in the safety mamangement literature. It has been defined as 'the characteristic of managing the organisation's activities to anticipate and circumvent threats to its existence and primary goals. This is shown in particular in an ability to manage severe pressures and conflicts between safety and the primary production or performance goals of the organisation' (Hale & Heijer, 2006, p31). This definition can be transposed from an organisational to a managerial level of analysis. The essence of managerial resilience being the ability to manage severe pressures and conflicts between safety and the primary performance goals of the organization (Flin, 2006). In order to achieve this, managers have to anticipate and either rebuff or circumvent threats to various goals, most notably to maximise production, while minimising the risks to safety. In some cases where this component of resilience fails – managers to not detect the threats; in others, the threats are recognised but the manager fails to take the requisite actions. So managerial resilience requires risk assessment, decision making and assertiveness skills. Production and safety goals can often be seen as competing, requiring the manager to make ‘trade-off’ or ‘sacrificial’ decisions. As Quinn (1988) points out, leadership is by its very nature inherently paradoxical and the most successful managers are those that can reconcile these paradoxes. In this paper, I first examine some notable organisational failures (the Swedish warship Vasa 1624; the space shuttles Challenger 1986 and Columbia 2003, and the oil platform Piper Alpha, 1988) where the erosion of managerial resilience appears to have played a key role, I then consider the key skill components of managerial resilience and how they might be measured and developed.
Measuring "Risk Perception Index" To Improve the Safety of Offshore Teams
Authors: McGrath T. , Mearns K.
Published: December 2007

Measuring the "Risk Perception Index" of individuals could provide a step change from the current plateau in HSE performance. By taking into account each individuals ability to detect, assess and react to hazardous situations and their knowledge and willingness to follow rules and procedures we may more effectively select personnel requiring non-technical skills training, then test its effectiveness and gauge the necessity for and effectiveness of existing hazard controls.

In this study "Risk Perception Index" was measured in a computer virtual reality simulation of the working environment. Seventy-two participants were immersed into a realistic scenario where they focussed on completing a task. Risk stimuli were initially presented in subtle ways, then more apparently, to detect the participant's degree of risk perception each participant's reaction to the stimuli was recorded and scored. 6% of the participants demonstrated excellent risk perception by "stopping the job" when they were uncertain. 33% of the participants demonstrated good risk perception by following rules. 38% of the participants initially demonstrated good risk perception then broke rules when put under additional time pressure but interpreted cues and went back to following rules. 23% of the participants broke rules, then failed to respond to cues and endangered themselves.

It is expected that a knowledge of "Risk Perception Index" will assist in the reduction of incidents and accidents where root causes include ‘poor risk assessment’.
Attacking Metropolitan Driving Hazards with Field-Proven Practices
Authors: Campbell N. , Tate D.
Published: December 2007

The exposure to risk from driving in field-type operations by companies engaged in the oil and gas industry is generally well recognized and, in many places, well addressed. Driving in a non-field or support-role environment provides similar exposure; however, even when this exposure is recognized, it is generally not well addressed. A challenge to a large oilfield service company was to leverage the best practices of a successful field-oriented journey management program for application in a metropolitan environment.

The number of miles driven on company business in this non-field metropolitan environment is substantial, but driving to and from work (commuting) was found to eclipse this exposure by 25 times. Because the greatest exposure to our metropolitan employees is commuting, the challenge becomes even greater—to develop a journey management plan that not only addresses business driving but also commuter driving.
Significantly Enhanced Landfarm Performance through the Use of Saline Water and Weekly Tilling
Authors: Al-Mahruki A. , Al-Mueini R. , Al-Mahrooqi Y. , Al-Sabahi A. , Roos G. H. P. , Patzelt H.
Published: December 2007

On the Fahud concession site of Petroleum Development Oman, an experimental landfarm for the bioremediation of petroleum hydrocarbon was constructed. It consisted of seven beds, laid out from a drilling mud/sand mixture, containing a total hydrocarbon concentration of 5.1% (w/w). The beds were fertilized at the onset and then tilled in weekly intervals. Duplicate beds were irrigated twice weekly with potable water, Reverse Osmosis (RO) reject water and brackish well water, respectively, and the hydrocarbon and metal content of the soil was monitored in monthly intervals. As a control, one bed was tilled regularly, but was not watered.

The beds irrigated with saline water showed a significantly improved performance over the fresh water beds or the control. Within four months of operation from March to June 2005, the hydrocarbon content of the soil in the saline beds had fallen to below two percent, where the control contained still above four percent. The findings correlate well with the observed higher microbial activity and greater microbial diversity that was observed in the saline beds.
Characterization of the Early-Time Mechanical Behavior of Well Cements Employed in Surface Casing Operations
Authors: Mueller D. T. , Eid R. N.
Published: December 2007

Pressure events that occur after surface casing cementation, such as casing integrity testing, formation integrity testing, etc. all impose stress upon the recently set cement sheath. The magnitude of stress will depend on the pressure state, casing thickness, cement sheath thickness and mechanical parameters of the cement and formation. Should pressure testing take place during the early stages of cement curing, the tangential stress imposed by the pressure event can exceed the tensile strength of the cement, thereby inducing cement sheath failure.

It is well documented that cement is much stronger in compression than in tension. In most wellbore pressure scenarios, cement fails in tension. The proportionality between the compressive strength and the tensile strength of set cement is generally assumed to be an 8:1 to 10:1 ratio. During typical pressure testing events, the cement will have a compressive strength ranging from the 500 psi required for the commencement of drilling operations to upwards of 2000 psi depending on the cement curing time. Accordingly, conventional wisdom would hold that the tensile strength of the cement would be in the range of 50 to 200 psi at the time of casing pressure testing. However, accurate prediction of the degree of pressure induced cement sheath stress requires more than a general correlation to derive cement tensile strength.

This paper characterizes the early-state physical properties and mechanical behavior of accelerated API Class A, G, H and ASTM Type I cement designs during the twelve hours following placement. The confined/unconfined compressive strengths, ultrasonic compressive strengths, tensile strengths, Young's Modulus and Poisson's Ratio of four commonly used "tail" cements as a function of time are presented. Predictions of induced stress in typical casing/hole size combinations as functions of pressure are also included. The results from this testing provides guidance as to when pressure testing of the casing/formation can take place without inducing damage to the set cement sheath.
Impacts From Oil and Gas Produced-Water Discharges on the Gulf of Mexico Hypoxic Zone
Authors: Parker M. E. , Satterlee K. , Veil J. A.
Published: December 2007

Shallow water areas of the Gulf of Mexico continental shelf experience low dissolved oxygen (hypoxia) each summer. The hypoxic zone is primarily caused by input of nutrients from the Mississippi and Atchafalaya Rivers. The nutrients stimulate the growth of phytoplankton, which leads to reduction of the oxygen concentration near the sea floor. During the renewal of an offshore discharge permit used by the oil and gas industry in the Gulf of Mexico, the U.S. Environmental Protection Agency (EPA) identified the need to assess the potential contribution from produced water discharges to the occurrence of hypoxia. The EPA permit required either that all platforms in the hypoxic zone submit produced water samples, or that industry perform a coordinated sampling program. This paper, based on a report submitted to EPA in August 2005 (1), describes the results of the joint industry sampling program and the use of those results to quantify the relative significance of produced water discharges in the context of other sources on the occurrence of hypoxia in the Gulf of Mexico.

In the sampling program, 16 facilities were selected for multiple sampling-three times each at one month intervals--and another 34 sites for onetime sampling. The goal of the sampling program was to quantify the sources and amount of oxygen demand associated with a variety of Gulf of Mexico produced waters. Data collected included direct oxygen demand measured by BOD5 (5-day biochemical oxygen demand) and TOC (total organic carbon) and indirect oxygen demand measured by nitrogen compounds (ammonia, nitrate, nitrate, and TKN [total Kjeldahl nitrogen]) and phosphorus (total phosphorus and orthophosphate).

These data will serve as inputs to several available computer models currently in use for forecasting the occurrence of hypoxia in the Gulf of Mexico. The output of each model will be compared for consistency in their predictions and then a semi-quantitative estimate of the relative significance of produced water inputs to hypoxia will be made.
Ten Years of Experience With Stabberless Casing and Tubing Running Systems—A Safe Way To Save Time
Authors: Kinzel H. , Kiess C. , Redzal S.
Published: December 2007

Traditional casing or tubing running involves one crew member working thirty feet above the rig floor, secured to the rig only by a safety cable. The crew member performing this job is called the stabber and his work is the most physically demanding and potentially dangerous job in the casing crew.

In 1996 a system was introduced that allows stabberless running of casing and tubing strings. The system mainly consists of a hydraulically activated remote controlled arm, named the StabMaster that is mounted in the derrick and a remotely controlled set of a spider an elevator equipped with interlock and sensor systems. This system not only eliminates the job function of the stabber but it also allows much more precise stabbing-in of the connection because once the well center position has been found at the beginning of the job, it is memorized by the electronic control system. This minimizes delays due to cross-threading or damaged connections due to an out-of-center alignment of the joint to be stabbed-in.

Although the primary function of the Stabberless System was to enhance the safety, 10 years of running experience with over 100 installed StabMaster systems worldwide shows that this system is capable of reducing casing and tubing or riser running time considerably, without compromising safety.

The paper describes the components of the Stabberless System and presents results of studies that were made in various locations in the world showing that running times can be reduced between 20% and 30%. The studies show also, that there is a direct correlation between using the Stabberless System and a decreasing number of recordable incidents.
The Snorre A Incident 28 November 2004: Lessons Learned
Authors: Pettersen G. , Moldskred I. O. , Ytredal E. B.
Published: December 2007

Statoil has carried out a comprehensive analysis of the underlying causes after a gas seabed blow-out on the Snorre field in the North Sea. The Norwegian authorities have described the incident as one of the most serious ever to occur in the North Sea. The causal analysis is based on the "Pentagon model". The results show the importance of viewing the technological, organisational and human factors in conjunction in order to best understand the underlying factors and to draw up relevant, focused follow-up measures.
Risk-Based Design—A Comparison of the Agbami and Captain FPSOs
Authors: Haughie I. J. , Duncan L.
Published: December 2007

The Captain FPSO in the United Kingdom Continental Shelf (UKCS) and the Agbami FPSO in the Gulf of Guinea, are examples of two upstream FPSO oil and gas developments. This paper will highlight how these designs, which began from the same core design codes and standards, were optimized to mitigate the local health, environment and safety risks. This optimization was achieved through risk based design.
Efficient Computational Method For Casing String Design
Authors: Akpan H. O. , Kwelle S. O.
Published: December 2007

Casing design should place the economics in its vital spot not compromising the Maximum Load concept consideration. The attainable, optimum condition is to design casing to withstand these problem imposed loads for the minimum cost. If this is not designed for, but is experienced, the casing string can fail and its remaining life forfeited.

This research study presents a computer program for casing string design using Microsoft Visual Basic 6.0. The program is menu driven and has a user-friendly interactive interface. Other features are its automated analysis steps and common engineering units.

The results obtained when tested with two other commercial casing software like DRILLPRO V3.0 and a spreadsheet software by Landmark were satisfactory; hence can be used. This program has an additional features of determining the overall cost of the selected strings (in the program database), pore pressure/fracture gradient prediction as well as the number of sacks of cement for slurry design.
A Computer Programme For Gas Parameters Measurement (GPM +PLUS)
Authors: Ibelegbu C , Agbor E. , Egbe T.
Published: December 2007

As the economic importance of Natural gas continues to grow, gas well surveillance equally generates more interest to the petroleum Industry. The static and flowing Bottom-hole pressures must be known in order to predict the productivity or absolute open flow potential of gas wells. Often, these parameters are measured using down hole gauges method of gas well test. In Gas wells, down hole parameters could be estimated using mathematical expressions relating separator conditions and the configuration of the Piping system, instead of measured directly using Gas well Test procedure thus saving lots of dollars.

The conventional method of Gas parameter measurement include the iterative method, the Sukkar and Cornell method, Cullender and Smith method. Others are Crawford and Fancher and the Poettman method.

All these methods involve very long and cumbersome Iterative/look up procedures. This makes the job of the field men very tedious, especially when the unit system changes. Similarly, data integrity is not guaranteed and could mar the estimation of parameters because data is far from actual. These iterative/look up procedures are always simplified by field men at the expense of accuracy.

Engineering problems are now becoming complex that their effective solution requires the systems approach using computers. This research work presents a Microcomputer program for the estimation of Static and Flowing Bottom hole pressure in gas wells, using the iterative method, Sukkar and Cornell method and the Cullender and Simth method. It utilizes a user-friendly window/ dialog based Visual Basic program functional with adjustable unit system.
A Simple Approach To Modelling Gas Well Deliverability
Authors: Eme Vincent O.
Published: December 2007

The Petroleum industry has recognized the value of monetizing gas resources. The Nigerian Government has stated its desire to grow the gas business. Numerous gas projects are either being planned or in the execution phase. The objective of this paper is to present a simple screening tool for evaluating gas well performance.

Numerical simulation is expensive and time consuming. Analytical approach to predicting gas performance is needed as a screening tool. The three components to performance prediction are: Initial rate estimate, prediction of rate decline as reservoir pressure depletes, and prediction of reservoir pressure decline due to production.

This paper shows that the decline in gas rate for various tubing sizes (3 ½", 4 ½", 5-1/2", and 7") on a dimensionless or normalized scale is similar. The resulting relationship combined with the material balance equation for depletion drive reservoirs gives a method of predicting performance of gas wells. This method is adequate for most gas reservoirs except for those under strong water drives.

The proposed paper will present details of how to develop a deliverability model for gas wells from very basic data. The forecast from this model will be compared with a 3-D numerical simulation result. The results from this method are close to those obtained from 3-D numerical simulation.
Feasibility Study on Application of Multiphase Pumping Towards Zero Gas Flaring in Nigeria
Authors: Lastra Rafael , Johnson Ikouwem
Published: December 2007

With the application of multiphase pumping unprocessed well effluent could be boosted over long distances without need for separation of phases. The Nigeria Oil Industry stands to benefit immensely from this application in the area of economical eradication of gas flaring, a menace that has robbed the industry of about $6.8 MM everyday. The conventional means of transferring gas to the sales point, which is by separation and compression, is very expensive which has occasioned the incessant flaring of associated gas. This paper compares the economic benefits of using MPP over the conventional method. Revenue from gas sales would benefit both the Nigerian government and the operators. Flares extinction would assure cleaner environment and reduction in health hazards, which have benefits of a global dimension.
Incorporation Of Environmental Reviews Into Facility Design – A New Challenge In The Petroleum Industry
Authors: Ukwuoma Okechukwu , Ononuju Charles N.
Published: December 2007

Environmental issues are no longer of concern only in a few "smokestack" industries. Today all businesses, especially the petroleum industry, are affected by environmental challenges and attempts by government to regulate those challenges. The successful management of these concerns require increasingly sophisticated knowledge, planning and techniques. Certainly, environment and safety are too hot buzz words for the petroleum industry in this 21st century. Complying to more stringent regulations will be expensive and will dramatically change the economics of many oil field developments. This is a guaranteed growth area in the industry. The petroleum industry is producing more water per barrel of oil than ever before- and the trend will continue. As a result crude oil lifting costs will escalate and corrosion will become an even more vexing problem.

Flow lines and umbilicals represent the "life" and "control" of subsea satellite wells. When either fails or is damaged the well either ceases to produce, reinject or cause spillages.

It is virtually impossible for any industry project to be 100% environmentally safe. And the modification of an existing facility in order to comply with the regulations inherently limits the flexibility and unfortunately is too expensive. Therefore during the early stages of new facility design, ample opportunity exists to implement design modifications that reduce environmental risks, while complying with the regulations.

This paper identifies and details some proactive environmental step procedure for use during the early design phases of a new facility. Completing these steps will ensure that all environmental issues are addressed and that all opportunities to optimize environmental safety have been effectively defined and analyzed. Furthermore, successful implementation of this procedure will certainly result in a combination of environmental benefits and positive economic returns.
Validating Reciprocal Productivity Index Parameter And Reserves Estimates Using Classical RE Techniques
Authors: Ifeanyi Ezuka
Published: December 2007

Reciprocal Productivity Index (RPI) is graphical production analysis method that provides us with the technique/ability to estimate descriptive engineering parameters, such as permeability, skin, drainage area, and to generate production forecasts and reserves based on those parameters, without the cost of full numerical simulation or extended buildup tests.

The method's theoretical basis arises from the fact that traditional constant rate or constant pressure (potential) boundary conditions are sufficient, but that the necessary boundary condition only requires that the sandface transmissibility remain constant over time. With that difference, it is possible to accurately evaluate production histories, in which both the rate and pressure are varying over time, using traditional well testing methods.

The reservoir average pressure can also be evaluated from routinely available rate and flowing pressure production data, using an extension of this reciprocal productivity index method. Traditionally, reservoir average pressure could only be determined from an extended duration build-up test. This procedure generally tends to underestimate the pressure, due to practical limitations on shut-in times. In addition, an error in the reservoir average pressure determination results in an error in the computed skin for the well. However, this new procedure provides an independent evaluation of skin and pressure so that they are not dependent on one another. The theory for the method is in the appendix.

This paper explains how we used this technique to evaluate engineering parameters and validate the estimated reservoir pressure using reverse material balance.
Net-To-Gross Ratios: Implications in Integrated Reservoir Management Studies
Authors: Egbele Emmanuel , Ezuka Ifeanyi , Onyekonwu Michael
Published: December 2007

Geoscientists and reservoir engineers are very well acquainted with the terms "net-to-gross (NTG)" and "petrophysical cut-offs" or just "cut-offs". The significance of these terms is ultimately to define productive zones in the reservoir for hydrocarbon exploitation. However, there has been marked misunderstanding surrounding the usage of the term, net-to-gross and implicitly, the derivation of cut-offs which are limiting values used in expressing the net-to-gross ratio. While the geologist may be concerned with the pay for evaluating hydrocarbon-in-place and the ultimately the estimation of economically producible reserves, the simulation engineer is more concerned with fluid flow for pressure support in the reservoir1.

The significance of this paper is to consider the different cut-offs selection methods, the varying interpretation of net-to-gross ratios and the implications inherent in such methods. A case study from a field in the Niger Delta is also carried out to reveal the impact of such selection criteria especially in rocks with congenital weak hydraulic properties which cannot be excluded at geologic correlation stage2. The effect of cut-off parameters on oil-initially-in-place (OIIP) calculation was also investigated and a sensitivity analysis carried out on the petrophysical parameters to reveal the impact of the dynamically conditioned cut-offs selection on the petrofacies. Multiple Monte Carlo realizations were also employed to obtain probabilistic OIIP estimates rather than a single deterministic result.
Integration of Geology and Petrophysics for the Characterisation of a Sandstone Reservoir
Authors: Ekpoudom O. J. , Ukaonu C. , Egbele E. , Onyekonwu M. O.
Published: December 2007

Abstracts

Poor reservoir characterization poses unique problems for exploration and production when the complex variation in lithology and diagenetic history that result in heterogeneous reservoir quality are not addressed. Optimizing field development requires a level of reservoir description that adequately defines vertical and lateral variations in reservoir quality.

An accurate reservoir description is a key to improved field development planning and management. This study shows how integrating petrophysics and geology helps in reservoir characterization.

This is illustrated with data from Niger Delta reservoir sandstone.
Water Coning Diagnosis using Spectral Analysis
Authors: Egbe ThankGod , Appah Dulu
Published: December 2007

Previous attempts at diagnosing the problem of water production in oil wells have been carried out without regard to the random and periodic nature of the problem. By treating the water-oil-ratio(WOR) as a stationary stochastic time series, a new model for diagnosing water production in oil wells based on Spectral Analysis/Fourier Transformation of the random production data is presented.

Key parameters used in the diagnosis and characterization are the autocovariance function, the autocorrelation function and the spectral density function. These functions are respectively used to obtain information about the spectral bandwidth, the correlation structure and energy distribution within each mechanism of water production

This method has been used to produce spectra for the diagnosis of coning using field data. Results show that coning can be modeled fairly closely as a low order autoregressive process with narrow spectrum. The position of the peak power in the spectrum and the periodicity of the autocovariance plot were used to uniquely characterize a typical coning process.
Intelligent Sand Management
Authors: Babs Oyeneyin M. , Macleod Chris , Oluyemi Gbenga , Onukwu Anthony
Published: December 2007

More than 70% of oil/gas reservoirs worldwide are in various degrees of unconsolidation requiring some elements of sand management. This is more so especially in the Niger Delta as activities extend to the more challenging deepwater environments of offshore West Africa.

Debate on the most effective sand management strategy has been intense for many years, with different companies adopting different strategies.

Development of appropriate strategy for the management of reservoirs with sanding problems is rather complex and requires an integrated approach to finding the optimum solution to solving the problem. This requires integration of key aspects of reservoir characterisation, drilling, completion and production technologies including sand tolerances (Seabed wellhead/flowlines, topside facilities) . Mitigation of sanding requires reliable sanding prediction, precise well design, accurate technology selection as well as optimum completion strategy. These are transient phenomena requiring a life cycle real time management.

In this paper attempts have been made to address the key issues with sand management. The paper goes further to provide a case for lifecycle intelligent sand management including the current technological innovations and future challenges in terms of technology gaps

Highlights of some of the development activities ongoing at The Robert Gordon University are also presented

The paper ends with an introduction of the Sand Management Network – A Network of upstream oil and gas operating companies and service providers with interest in sand management. The Network purpose is to share successful methods and technologies as well as promote best practices in the management of sand.
Drag Reducing Agent Test Result for ChevronTexaco, Eastern Operations, Nigeria
Authors: Ibrahim John U. , Braimoh Lucky A.
Published: December 2007

The result of a field test of ConocoPhillips Specialty Products Inc.'s (CSPI) LiquidPowertm Flow Improver, a type of Drag Reducing Agent (DRA), at ChevronTexaco's Inda platform in Nigeria is reported in this paper.

Analytically, Inda platform started experiencing deviation in pipeline pressure drop between the actual and theoretical values in about April 1998 and gradually worsened ( Figure 4 ). However, the impact was not felt as the field was under production curtailment. But in March 2003 when the need to increase production arose, it was discovered that the throughput could not be increased beyond 18,400 bopd. Consequently, various analyses and trouble shootings were carried out. Some of the results point to, reduction in the internal diameter of the pipeline, pipeline frictional losses, repair works needed on pumps amongst other problems. And subsequently, the search to finding a technology that would enable the production of additional 2500 bopd shut-in as a result of this pumping handicap commenced. Several companies’ drag reducing agents were evaluated and ConocoPhillips’ LiquidPowertm Flow improver was selected for field test.

Upon selection, the LiquidPowertm Flow improver was imported and tested on the Inda PP. The primary test lasted for about 36 hours and was followed by a prolonged secondary test. Some of the challenges faced were mobilizing the hard and soft wares for the test since all the equipment were been imported from Europe (CSPI office base). Also because the Inda crude is injected to a third party facility, we had to contend with seeking approval of the third party company. Additionally since this is the first time the product is being tested in ChevronTexaco Nigeria, we had to contend with pioneer status challenges like extensive discussions, buy-in difficulties, money sourcing, logistics, etc.

At the end of the testing period, discussion and analysis were made on what should be the way forward for the extensive use of the DRA and thereafter business decisions were made.
Critical Success Factors for Well Stimulation
Authors: Nnanna Erasmus J. , Ajienka Joseph A.
Published: December 2007

The popularity of matrix stimulation as production enhancement operation is evidenced by the abundance of technical resources on the subject matter. Developments in technology have continued to address the challenges of the operation.

This paper identified three critical success for well stimulation as good candidate selection, well-engineered treatment design and improved field operations. The approach was simple and involved a review of existing case histories with a view to identifying issues that need closer attention for the optimization of matrix treatments.

The use of the R-Factor for candidate selection was revisited and an expression that excluded BHP data and rock and fluid properties was derived to ease the calculation of this factor.

An attempt was also made towards the design of the treatment volume of the acid based on the completion details of the well. Charts were presented for this. Field cases that illustrate the importance of this new approach were also presented.
Application of a Novel Orienting Technology Leads to Oil Gains From Short String Through Tubing Re-Perforation in the Niger Delta
Authors: Ogunnifa A. , Ene E. , Umurhohwo J.
Published: December 2007

This paper presents the application of a new technology for rigless short string perforating operations. The use of this technology has led to quick and cheap oil gains from wellbores which otherwise have been traditionally programmed for more expensive major rig workover. Added to this is the elimination of complicated logistics and the achievement of a safer, faster and cheaper means of perforating reservoirs accessed via the short string in dual completions.

This new system for short string perforations eliminates most of the previously identified problems with existing perforating systems, without compromising performance, reliability and repeatability. Its use involves the electric line deployment of perforating guns below an electromagnetic orienting and correlating tool in the short string. The orienting and correlating tool detects the long string as the tool is rotated. The perforating gun can then be oriented 180

degrees away from the long string thus allowing for the safe detonation of the gun. The system provides a positive identification of the long string without requiring chart corrections or multiple string rig-ups.

This technique was successfully applied in the short strings of six dual completion oil wells located offshore in the Niger-Delta region by asset teams in Chevron Nigeria.

This paper describes the field performance of this tool, discusses the job planning process, the execution process, and presents production performance data available from three of the wells.