bluuebunny/crossref_metadata_2025 huggingface dataset:
Equilibrium Ratios of Water in the Water-Triethylene Glycol-Natural Gas System
Authors: Scauzillo Frank R.
Published: June 2014

Equilibrium data which should be useful in the design and/or evaluation of glycol dehydration units were prepared from an analysis of various published data and the correlation of these data by the use of the thermodynamic equilibrium ratio. The equilibrium ratios of water are used to solve the glycol absorber problem; such solutions are necessary to define the number of trays and the glycol circulation rate needed to meet drying requirements.

Activity coefficients were obtained which relate directly to the equilibrium ratios of water in the water-TEG-natural gas system. These activity coefficients have been used to calculate the equilibrium dew points for aqueous TEG concentrations of 60 to 99.9 weight per cent for the temperature range of 40 to 120F. They also provide a means of calculating equilibrium ratios for water in the water-TEG-natural gas system; this applies to any desired TEG concentration and to the temperature range from 40 to 120F.

Introduction

During the last several years, the drying of natural gas with aqueous triethylene-glycol (TEG) solutions has become very prominent. Most users of TEG as a drying agent have been satisfied with the performance of TEG solutions at the conditions used; however, there always has been some discussion of the drying ability of TEG solutions at conditions not commonly encountered such as temperatures below 50 or 60F, but more particularly temperatures above 100F, and pressures above 1,000 psia. Today, when higher wellhead temperatures such as 120F are more commonly encountered many are skeptical of TEG's ability to dry sufficiently well to provide dew points around 32F, which is generally the maximum tolerable when attempting to dry a gas to contract specifications of 7 lb/MMscf.

These views probably have evolved to some extent from the days when suppliers would not guarantee dewpoint depressions in excess of 65 to 75F. Also, the feelings about TEG drying may have arisen from the lack of information about the equilibrium relation of water in the drying operations.
Investigation of the Mitigation of Lost Circulation in Oil-Based Drilling Fluids by Use of Gilsonite
Authors: Guo H.. , Voncken J.. , Opstal T.. , Dams R.. , Zitha P.L.J.. L.J.
Published: June 2014

Fluid-loss control is an essential property of oil-based mud (OBM) that can affect the success of drilling operations. This paper presents an investigation of the mitigation of lost circulation in OBM by use of leakoff-control-additive gilsonite. A simple physical model was developed to describe the static-filtration process considering the formation and properties of the filter cake. Both high-pressure/high-temperature (HP/HT) American Petroleum Institute (API) press and core-flow-filtration experiments were performed to evaluate the leakoff behavior of OBM. Core-filtration experiments were carried with the aid of a computerized-tomography (CT) scanner to monitor the invasion of the filtrate into the sandstone core at time intervals. In the long time limit, the model predicts that the fluid loss follows the classical Carter equation; that is, the volume of leakoff increases as the square root of time for the static filtration through a filter paper and through the sandstone core. Dual-mode filtration diminishes the rate of fluid loss considering the effect of emulsion. The model also provides a relation between pressure drop and filtrate rate, which can be used to estimate the permeability of filter cake in the experiment. The leakoff behavior with additive observed in the experiment is well-explained by the microstructure of rapid-buildup filter cake, which is mainly responsible for the control of fluid loss. The role of different components of OBM, such as solid particles, emulsion droplets, and additives, is discussed in light of our observations.
An Economically Successful Miscible-Phase Displacement Project
Authors: Block W.E. , Donovan R.W.
Published: June 2014

A slug-type miscible-phase displacement project has been in operation in the 29D pool of the Midway-Sunset field, Kern County, Calif., since March, 1958. This project has resulted to date in the production of 230,000 bbl of additional oil which can be attributed to propane injection. The project is profitable, and the investment was returned in two years. The pool production rate during April, 1960, was 900 B/D, which was 540 B/D more than the previous gas-injection operation.

Reservoir pressure is currently about 1,300 psia. The pool now has four injection wells and 12 producing wells, all drilled on 10-acre spacing. To date, a slug of 18 million gal of propane has been injected.

Impressive oil stimulation, accompanied by gas-oil ratio reduction, has been observed in most of the first-line wells and several of the second-line wells. Breakthrough of propane occurred in the first-line wells early in the life of the project but has occurred in only one second-line well. Continued production of stimulated wells has shown that additional oil can be recovered after propane breakthrough.

The original plan of operations called for injection of a propane slug followed by gas. However, the well's demonstrated ability to produce large quantities of oil after propane breakthrough, and the attendant depletion of the slug, caused the plan of operations to be modified to include recycling of produced propane in a miscible state.

Introduction

A slug-type miscible-phase displacement project was started in the 29D pool in March, 1958. The pool is located in the Midway-Sunset field about three-miles southeast of Taft, Kern County, Calif.

This reservoir was chosen for a miscible-phase displacement secondary recovery program because of the following factors.The quantity of 31°API oil remaining in the reservoir was great enough to make secondary recovery attractive.The pool pressure of 1,500 psia and temperature of 1800° F insured direct miscibility of a propane-injection stream with the reservoir oil.Well configuration and condition and the type of completion were such that good control could be maintained.The production mechanisms were known and understood.The pool size, and the reservoir rock and fluid characteristics were known.

Under these circumstances, it was believed the process could work if properly engineered. As of April 1, 1960, the project had paid out and now is operating on a profitable basis.
Use of Oxygen Scavengers To Control External Corrosion of Oil-String Casing
Authors: Schremp F.W. , Chittum J.F. , Arczynski T.S.
Published: June 2014

This paper describes a laboratory study of causes of external casing corrosion and the test work that led to the use of oxygen scavengers to prevent this attack. External casing failures are classified as water-line, casing-casing, collar and body failures. A corrosion mechanism based on principles of differential oxygen availability is developed that is consistent with facts known about each kind of failure. The field use of oxygen scavengers is depicted as a direct result of the laboratory study.

A part of the paper is devoted to reporting on the field use of hydrazine to control external casing corrosion. Results of field measurements made over a period of several years are presented as evidence of the effectiveness of the hydrazine treatment. The first conclusion reached is that the use of hydrazine materially reduces the cathodic protection requirements for treated wells. This result is interpreted to mean that a reduction is taking place in the amount of corrosion on the casing. Results indicate also that hydrazine shows its greatest usefulness within the first 12 to 18 months after a well is completed when pitting corrosion is likely to be most active.

Introduction

According to surveys sponsored by the National Association of Corrosion Engineers, the cost of repairing casing leaks caused by external corrosion may exceed $4 million per year. In addition, well damage and lost production resulting from casing leaks probably costs the petroleum industry an additional $5 to $6 million per year.

Concern about the cost of external casing corrosion led to an extensive laboratory study of factors causing this external corrosion and to the development of a new approach to its prevention. This paper presents a discussion of various causes of external casing corrosion, details of laboratory studies and the results of the field use of an oxygen scavenger in well cementing fluids to prevent the external corrosion of oil-string casing.
A Procedure for Measuring Contact Angles When Surfactants Reduce the Interfacial Tension and Cause Oil Droplets to Spread
Authors: Adejare O.O.. O. , Nasralla R.A.. A. , Nasr-El-Din H.A.. A.
Published: June 2014

Viscoelastic surfactants (VESs) are used as diverting agents in carbonate matrix acidizing. However, these surfactants can adversely affect the wettability around the wellbore.

Receding contact angles were measured with the conventional method to study the effect of spent-acid solutions with an amphoteric amine-oxide VES and the mutual solvent ethylene glycol monobutyl ether (EGMBE) on the wettability of Austin cream chalk rocks. The conventional method involves the injection of oil droplets into the surfactant solution. However, contact angles could not be measured when oil droplets were injected into spent-acid solutions with VES and EGMBE, because low oil/acid interfacial tensions (IFTs) cause them to spread on the rock surface.

A new procedure was used for these contact-angle measurements. Rocks were centrifuged in spent-acid solutions with VES and EGMBE, so that the surfactant changed the interfacial properties of the rock. Then, contact angles were measured in spent acid with hydrochloric acid (HCl) only, to prevent VES and EGMBE from reducing the oil/acid IFT. The effect of the surfactants in the spent acid on the acid/rock and acid/oil IFT, which is the wettability, is shown by the difference in contact angles before and after centrifuging.

With the new procedure, a spent-acid solution with HCl, 1 vol% of VES, and 10 vol% of EGMBE made an oil-wet rock water-wet and a water-wet rock strongly water-wet at 25°C. This suggests that an EGMBE post-flush enhances the relative permeability to oil, under the parameters investigated.

Contact angles are a function of the oil/rock, acid/rock, and oil/acid IFTs. However, the wettability of the rock is a function of the oil/rock and acid/rock IFT only. The new procedure measures contact angles in such a way that the surface-active agents change the oil/rock and acid/rock IFT only so that “spreading,” an artifact caused by oil/acid IFT reduction, may not occur.
A Simple Method for Correcting Spot Pressure Readings
Authors: Brons F. , Miller W.C.
Published: June 2014

Pressure information for use in material-balance calculations is obtained, where possible, from pressure build-up surveys in shut-in wells. Using proper extrapolation methods, static pressures are obtained which, by averaging, give the field static pressure.

Often, particularly in fields with a large number of wells, only spot pressure readings are available. A graphical method is presented here which enables the determination of the corrections which must be applied to the spot readings to give an estimate of the static pressure. Although the static pressures thus obtained are not so reliable as those from build-up surveys, they are more nearly correct than the spot readings themselves for use in material-balance calculations.

Introduction

The average static pressure in a bounded reservoir is determined from a number of individual-well pressure measurements. Where pressure build-up curves are available, extrapolation methods such as described in Ref. 3 may be used to determine the static pressure in the drainage area of each individual well.

The possibility of using pressure build-up curves presupposes that each well being surveyed is closed in during a certain period and that, during this time, a pressure recorder is left suspended in the hole. For surveys in fields with a large number of wells, this is usually not feasible for economic and other reasons. Either a large number of pressure recorders would have to be used simultaneously or, using a limited number of recorders, the time interval needed to complete a field-wide survey would be too long. The data obtained for this incomplete coverage are insufficient to permit reliable averaging of the few calculated static pressures over the entire reservoir.

In many such cases another type of pressure information is available, i.e., spot pressure readings. During this type of pressure survey all wells are closed-in simultaneously and, after a reasonable shut-in time (e.g., three days), pressure readings are taken by running the recorder in and out of each successive well. These surveys, which are less expensive, are often taken at regular intervals, say once or twice a year.
Impact of Uncertainty in Estimation of Shale-Gas-Reservoir and Completion Properties on EUR Forecast and Optimal Development Planning: A Marcellus Case Study
Authors: Jayakumar R.. , Rai R..
Published: June 2014

The use of multistage-fractured horizontal wells has made production from shale-gas plays feasible. The production history from these wells is characterized by long linear transient flow. The key reservoir (nature) and completion (nurture) properties that affect flow behavior of the well are permeability, original hydrocarbon in place (OHIP), number of hydraulic fractures, fracture area, and fracture spacing. Understanding the interrelationship between these parameters is critical for optimal development of shale-gas-resource plays. The proposed shale-gas workflow uses a hybrid analytical model. An analytics-based diagnostic process analyzes well performance history, and a numerical model validates the feasible history-match models for representative forecasts. The model results allow the user to capture the range of uncertainty in estimating individual reservoir or completion properties, such as permeability, fracture area, and fracture spacing. The diagnostic process provides the relationship between key factors dictating well performance, such as OHIP, effective fracture area, effective reservoir permeability, effective fracture spacing, and well spacing. In this paper, wells from the Marcellus play in Pennsylvania, USA, are evaluated by use of the proposed shale-gas workflow. Surveillance is an integral part of this workflow. The paper shows how surveillance can be used for resource management and exception management. Along with data mining, the workflow accelerates the learning curve to evaluate the effectiveness of current field practices. The results help with understanding the effectiveness of proppant pumped, the potential number of contributing clusters, and production issues. Continued surveillance reduces the uncertainty surrounding all parameters. This knowledge base can then be used to optimize the asset-development strategy, maximizing the return on investment.
The Stability of a Pipe Stand Racked in a Derrick, Part 1—Foundation
Authors: Sawaryn S.J.. J.
Published: June 2014

The paper presents an exact analytical solution using higher-order functions for the deflection and buckling of a simple pipe stand in a derrick, modeled as an inclined slender column, with self-weight and pinned at both ends. The results are consistent with industry practice where an intermediate finger board is used to support 93-ft stands of both 2⅜- and 2⅞-in. steel pipe but is not required for 3½-in. pipe. These observations suggest a suitable safety factor for application in other cases. The results are an important limiting case for the general pipe-stand model presented in Part 2.

Buckling lengths are presented for a range of pipe sizes and types. Sensitivities, such as the presence of tool joints, differences in material, wear, and the effect of pipe stick-up above the top racking board, are also introduced. Although there is good agreement between the theory and operational practice for triples, further investigation is needed for quads.

Construction columns are normally designed to support significant loads, and in most cases, self-weight plays only a minor role. This is not the case for a simple pipe stand in a derrick, for which stability is solely dependent on self-weight. More-formal analysis of these conditions is warranted because of the trend of increased mechanization and the need to preserve safety and improve operational efficiency.

To the author's knowledge, there is no existing industry guidance for the flexing and stability of pipe stands in a derrick.
Fast Simulation of Polymer Injection in Heavy-Oil Reservoirs on the Basis of Topological Sorting and Sequential Splitting
Authors: Lie Knut-Andreas , Nilsen Halvor Møll , Rasmussen Atgeirr Flø , Raynaud Xavier
Published: June 2014

We present a set of algorithms for sequential solution of flow and transport that can be used for efficient simulation of polymer injection modeled as a compressible two-phase system. Our formulation gives a set of nonlinear transport equations that can be discretized with standard implicit upwind methods to conserve mass and volume independent of the timestep. In the absence of gravity and capillary forces, the resulting nonlinear system of discrete transport equations can be permuted to lower triangular form with a simple topological-sorting method from graph theory. This gives an optimal nonlinear solver that computes the solution cell by cell with local iteration control. The single-cell systems can be reduced to a nested set of nonlinear scalar equations that can be bracketed and solved with standard gradient or root-bracketing methods. The resulting method gives orders-of-magnitude reduction in run times and increases the feasible timestep sizes. In fact, one can prove that the solver is unconditionally stable and will produce a solution for arbitrarily large timesteps. For cases with gravity, the same method can be applied as part of a nonlinear Gauss-Seidel method. Altogether, our results demonstrate that sequential splitting combined with single-point upwind discretizations can become a viable alternative to streamline methods for speeding up simulation of advection-dominated systems.
Preconditioning for Efficiently Applying Algebraic Multigrid in Fully Implicit Reservoir Simulations
Authors: Gries Sebastian , Stüben Klaus , Brown Geoffrey L. , Chen Dingjun , Collins David A.
Published: June 2014

Fully implicit black-oil simulations result in huge, often very-ill-conditioned, linear systems of equations for different unknowns (e.g., pressure and saturations). It is well-known that the underlying Jacobian matrices contain both hyperbolic and nearly elliptic subsystems (corresponding to saturations and pressure, respectively). Because a reservoir simulation is typically driven by the behavior of the pressure, constrained-pressure-residual (CPR)-type two-stage preconditioning methods to solve the coupled linear systems are a natural choice and still belong to the most popular approaches. After a suitable extraction and decoupling, the computationally most costly step in such two-stage methods consists in solving the elliptic subsystems accurately enough. Algebraic multigrid (AMG) provides a technique to solve elliptic linear equations very efficiently. Hence, in recent years, corresponding CPR-AMG approaches have been extensively used in practice.

Unfortunately, if applied in a straightforward manner, CPR-AMG does not always work as expected. In this paper, we discuss the reasons for the lack of robustness observed in practice, and present remedies. More precisely, we will propose a preconditioning strategy (based on a suitable combination of left and right preconditioning of the Jacobian matrix) that aims at a compromise between the solvability of the pressure subproblem by AMG and the needs of the outer CPR process. The robustness of this new preconditioning strategy will be demonstrated for several industrial test cases, some of which are very ill-conditioned. Furthermore, we will demonstrate that CPR-AMG can be interpreted in a natural way as a special AMG process applied directly to the coupled Jacobian systems.
An Adaptive Hierarchical Multiscale Algorithm for Estimation of Optimal Well Controls
Authors: Oliveira D.F.. F. , Reynolds A..
Published: June 2014

In determining the optimal well controls by maximizing net present value (NPV) for the remaining life of a reservoir, one typically defines the length of the control steps a priori. Moreover, these control steps are often the same for all wells. We provide a scale-splitting/merging method for adaptively selecting the number and the lengths of control steps as the overall optimization proceeds. We start with a reasonably small number of control steps and find the associated optimal controls by maximizing NPV. Both the adjoint-gradient-based steepest-ascent method and ensemble-based optimization (EnOpt) are considered as optimization algorithms. Because the correlation length used to generate the ad hoc covariance matrix indigenous to EnOpt affects the results, we implement a simple method to reduce the correlation length as the optimization proceeds. This enables EnOpt to generate a good approximation for well-control problems in which the optimal solution is bang-bang. The adaptive approach is applied to two example problems, and the results are compared with those obtained with a predetermined number of control steps.
A Review of the Literature: Motor Vehicle Safety Initiatives in the Oil and Gas Extraction Industry
Authors: Retzer Kyla , Hill Ryan , Burton Jason
Published: June 2014

BACKGROUND

Motor vehicle crashes are the leading cause of death in the U.S. oil and gas extraction industry, resulting in approximately thirty worker fatalities every year. Many oil and gas extraction companies have developed comprehensive motor vehicle safety programs; some have described the impact of those programs at industry conferences, in industry magazines, or in trade journals. The purpose of this paper was to conduct a systematic review of the motor vehicle safety initiatives that have been published in this industry. This paper will summarize the reported effectiveness of these initiatives, identify the research gaps in the literature, and describe recommendations to enhance future motor vehicle safety research in the oil and gas extraction industry.

METHODS

To be included in this review, articles had to meet the following criteria: 1) available in an online database; 2) published during 1990-2012; 3) describe a motor vehicle safety initiative within an oil and gas extraction company; and 4) objectively measure the effectiveness of at least one component of a motor vehicle safety initiative.

RESULTS

The authors identified 38 articles that met the criteria above. Oil and gas extraction companies have employed a variety of interventions to improve motor vehicle safety among their workforce; the most common found in this review were in-vehicle monitoring, journey management, driver training and qualification, and driver fitness and alertness.

CONCLUSIONS

There is a need to improve the quality of research articles examining motor vehicle safety in the oil and gas extraction industry. The authors’ systematic review found a limited number of published articles describing motor vehicle safety initiatives in the oil and gas extraction industry, particularly in the U.S. In addition, the articles often suffered from a weak study design and did not evaluate the long-term impact of their initiatives over time. There is a continued need for oil and gas extraction companies to evaluate the impact of their motor vehicle safety initiatives and publish their findings in peer-reviewed journals to enhance the dissemination of effective strategies.
A Precise Process Safety Information: The Fundamental Building Block for a Strong Safety Management Program
Authors: Laskar Sandipan
Published: June 2014

Process safety has become one of the inevitable elements in keeping businesses in various industries sustainable. Various industries have suffered painful lessons from incidents and have taken steps to prevent similar tragedies from re-occurring. The Bhopal incident in 1984 and the more recent Deepwater Horizon incident are few examples which show the catastrophic impact of process safety related incidents. Although eliminating risk entirely is not feasible, especially in handling highly hazardous chemicals, recent progress in process safety has improved safety performance through recognizing the risk and implementing safety measures to prevent or mitigate catastrophic consequences.

A safety management system provides a systematic way to identify hazards and control risks while maintaining assurance that these risk controls are effective. The main objective of any safety management program is to reduce the risk to a level that is as low as is reasonably practicable. Although all of the elements of a safety management program are important, one of the core requirements is maintaining accurate process safety information. If these data are not maintained, discrepancies cannot be identified during the Process Hazard Analysis or Pre Startup Safety Reviews, Procedures and Training elements will be based on incorrect information, and loss of containment or other catastrophic events could result from problems with Hot Work, Mechanical Integrity, and other elements. This paper proposes a new methodology to ensure proper documentation of the critical systems and introduces a three phase system to ensure correct, up-to-date process safety information. The paper illustrates how up-to-date process safety information leverages overall process safety management program and provides a list of frequently used process equipments along with the available RAGAGEP for design, inspection and testing.

The paper will assist facility personnel to utilize good engineering practice in design and documentation of critical systems, to meet both onshore and offshore process safety requirements, and to develop consistent company best practices for process safety management. In addition to the documentation methodology, the three phase approach furnishes a company with an effective tool for designing, developing and implementing a PSI program that will not only be in compliance with regulation, but will provide a basis for maintaining process, production and facility equipments in a reliable and safe operating condition.
Searching for Safety Management Headlights
Authors: Veley Carl
Published: June 2014

Managers cannot guide a business solely with a balance sheet. That is like trying to drive looking only in the rearview mirror. They need ‘headlight’ indicators such as market forecasts, recruitment prospects, and competition reports to guide their future. In the safety arena, Managers rely on trailing indicators – rearview mirrors based on frequency and severity of past accidents. Efforts to produce reliable leading indicators for accident prevention headlights have been published for many years (Heinrich, 1931) but they have had limited success and are generally based on assumptions that have been largely discredited (Manuele, 2011).

One leading indicator proposed at previous SPE International Conferences (Veley, 2002 and Veley et al, 2004) has been applied to varying extents by several companies. It involved categorizing stated corrective actions using standard management theory definitions for: 1) direct action, 2) supervision, and 3) management. Points were awarded accordingly, averaged, and modified with minor adjustments to produce an index reflecting overall problem solving effectiveness. Managers have used this index to set safety goals and standards (Ritchie, 2012), but that approach has serious flaws.

Initially this metric seemed to be the long-sought management headlights because it is derived from corrective actions and is linked to probability of accidents happening in the future. After analyzing several thousand accident reports where this metric had guided corrective action generations, the author found that it had side effects that caused subtle but serious harm. Safety headlights are still needed to show if the road ahead is getting better or worse, and measurements based on the worth of corrective actions would seem to have the best chance of meeting that need, if the undesirable side effects can be eliminated. An objective of this paper is to show how that can be achieved.
Safety Transformation: The Challenge of Change to Become an Injury-Free Organization
Authors: Thanajaro Thananan
Published: June 2014

The Montara incident in 2009 is a wakeup call for SSHE transformation in PTTEP. In 2011, corporate SSHE had an organizational reform to strengthen the corporate oversight and to support PTTEP growth in international arena. The "Step Change in SSHE" program has then been introduced based on the core beliefs that the goal of zero injury is achievable and SSHE is a core value that must be integrated into every aspect of the business. The program targets leadership and commitment at all levels, strategic SSHE communication, management system and staff engagement, all of which to create common understanding and shift the company SSHE culture in which all staff are treated with trust and respect. The program is committed to achieving an LTI-free organization by 2013.

Through the comprehensive 5-Act Step Change in SSHE program, new campaigns are introduced and existing campaigns are reinforced. The safety leadership workshop was implemented for CEO and top management to brainstorm and make a commitment towards company SSHE direction. SSHE moment in all meetings has adopted to encourage the concept of SSHE is everybody’s responsibility. SSHE Management System has been improved to ensure the minimum requirements in managing SSHE. New SSHE KPIs structure, which KPIs are assigned to all levels from CEO to individuals, has been implemented throughout the company. The main elements are the incorporation of leading and lagging indicators of personal safety as well as process safety. SSHE climate survey was also conducted to measure the level of SSHE Culture based on Safety Cultural Maturity Model. The average survey result was 3.3 (scale 0-5). With the appropriate interventions, PTTEP aims for 4+ in 2014.

At the end of 2011, the program has proved to reduce the overall company statistics, especially LTIF which reduced by 40% from 2010. This is a remarkable step towards an LTI-free organization by 2013.

The Step Change in SSHE journey will be profoundly continued. Top management leadership and everyone’s commitment are the most important parts of our success. We need to build effective and sustained compliance culture to underpin our License to Operate.
Integrating Social Performance Management: A Comparison with HSE Performance Management
Authors: Snodgrass Mary Beth , Milius Soledad , Howard Joanne , Energy Spectra , Hafner Colby
Published: June 2014

The discourse on social performance in the extractive industries has advanced considerably over the past decade. However, when it comes to integrating social performance into organizational cultures and practices, significant challenges remain for many extractive companies. This article aims to provide practical insights and recommendations on how to improve social performance integration by drawing comparisons with health, safety and environment (HSE) performance.

Companies are just beginning to understand the benefits of and savings associated with managing social performance. The advanced integration of HSE into budgets and daily activities is due, in part, to the fact that managing health, safety and certain aspects of environmental issues can have more readily observable financial savings and rewards for companies. In contrast, proactive, fit-for-purpose management of social risk and performance pays off in the long-term but can be uncomfortable and challenging in the short-term.

Extractive companies could improve their social performance by drawing on lessons learned from HSE’s integration into company culture and practices. These lessons come from two key areas: risk-based approaches and winning the hearts and minds of employees.
Why Culture Matters
Authors: Duhon Howard
Published: June 2014

Over the past 20 to 30 years the safety culture of the oil patch has changed dramatically resulting in large decreases in accident and injury frequency. Additional changes in culture might achieve further gains. Though engineers and managers understand that culture matters, most will have only vague ideas about what culture is, what it does that is important and how it might be improved.

The paper addresses culture based on several key concepts including:

Culture is learned. There are cognitive and social limits to the kinds of cultural attributes we can learn. Most learning in the areas of culture is tacit rather than explicit. Team dynamics impact learning by individuals in a group. Culture is created by leaders. Managers manage within a culture.

The paper weaves together important insights from leading researchers in several fields of study including:

Schein - organizational culture and leadership Argyris, Schon – action science Barron, Kerr – team dynamics Shelley, Fisk - social cognition Klein – naturalistic decision making Weick – sensemaking Edward Wilson – social evolution Taylor, Van Every – pragmatics (communication theory)

This paper provides background information for those interested in improving the culture of their company and/or of the industry and attempts to answer the question "Why does culture matter?"
A Tool Case Study on the Application and Benefits of Alternate Energy Supply Technologies
Authors: Rowbottom R. A , Kuykendall D.
Published: June 2014

The global issues related to greenhouse gas emissions, cost of electricity, and reliability of electrical supply are driving companies to evaluate options for alternative energy sources to power facilities. A robust screening tool was necessary to identify whether more environmentally sound and cost effective options were available to meet facility energy needs. This paper outlines the development, application and advantages of an alternate energy generation assessment tool for determining the feasibility of installing co generation and/or self generation to provide electrical power at company owned facilities. This tool, which is quick and easy to use, provides significant advantages over the traditional approach of engineering studies, which are often time consuming and expensive.

The tool evaluates various factors to compare utility provided power to other options including fuel cells, photovoltaic, and natural gas turbines. The power supply types are evaluated against a number of criteria including feasibility, energy quality, greenhouse gas emissions, cost, payback period and other factors.

To be a global assessment tool, the format needs to be adaptable to various conditions regarding supply and reliability in diverse power supply markets.

The application of the "alternate energy cogeneration tool" to various operation facilities in a global setting will be discussed. A case study will be outlined that concluded with the selection of a 300kW natural gas fuel cell at a facility. This resulted in annual savings of $477K in purchased electrical power and reduced greenhouse gas emissions by 1,578 metric tons of carbon dioxide equivalent (CO2e).

Calculations of greenhouse gas emissions (CO2e) will be detailed to show how to capture the environmental advantages of co-generation and self generation applications utilizing an internal carbon reporting system. These environmental benefits can be incorporated in overall sustainability reporting by the user, both internally and externally.
Community-Driven Development: A New Approach to Social Development in the Niger Delta
Authors: Reider Susan
Published: June 2014

The Global Memorandum of Understanding (GMOU) process was initiated in 2005 by Chevron Nigeria Ltd. (CNL) as a significant departure from prior operating experience in the Niger Delta. Previously, the company’s community relations spend primarily targeted "host communities" and involved relatively large, signature projects like schools and hospital buildings. Serious conflict between "have" and "have-not" communities, and between communities and the company, had been escalating for years. The new approach, based on a community-driven development model, was intended to deliver equitable and sustainable social investments, build capacity in civil society and promote peace and security. This paper will describe the model, as well as programs for training and capacity-building, governance, planning and field research.

CNL’s model of community-driven development was based on earlier efforts by Great Britain’s Department for International Development (DfID) and the Ford Foundation. The GMOU effort represented the model’s first application in the international oil sector, as well as in Nigeria on a large scale.

By 2007, 72 projects had been implemented in 50 communities. By 2011, 200 projects were completed. The three-year GMOUs have been renewed twice and conflict around Chevron facilities has been considerably reduced. These results can be attributed to several factors: the community-driven development model, up-front investment in training and capacity-building, transparent engagement with government at all levels, and long-term commitment to the process by all major stakeholders. The results also indicate that, in extreme poverty areas, social investment may have a more lasting, measurable and direct impact on beneficiaries when funds are directed to projects that enjoy a high level of community "ownership," rather than to large-scale initiatives.

Community-driven development planning, coupled with transparent governance, can be used in other West African, Southeast Asian and Latin American locations where oil companies are considering social investments. It may be especially relevant in situations where traditional development approaches have failed and company operations are negatively impacted by local conflict.
Case Studies Demonstrating Sustainability and Risk Evaluations in Environmental Due Diligence for Upstream Oil and Gas Transactions in Alberta
Authors: Nicholas L. , Lozier W.
Published: June 2014

Recent advances in the unconventional oil & gas plays have resulted in increased investment activities in the upstream space aimed at monetizing large acreage lease holdings as well as cash management to fund exploration and development of new plays. Often these transactions involve the global investment community at both the private and government owned company level. Coupled with these transactions, Global corporations are moving from a narrow view of environmental health and safety (EHS) management to a holistic Corporate and Social Governance (CSG) approach that includes EHS as just one component of managing a sustainable and profitable business. To compete successfully, it is critical that investors understand the implications of CSG risk management strategies and their impact on sustainable business growth plans.

Traditional due diligence activities have focused on quantifying and minimizing EHS impairment liabilities, at best considering a snap shot of current conditions and regulatory operating status. This is due to the fact that the cash flows of established operations are well understood. However, for upstream oil and gas plays with little to no operational assets, the most significant risks are not environmental impairment but rather are the environmental and sustainability risks that could affect asset development. Further, most oil and gas investments involve vast amounts of land and leaseholds, often at various stages within the project life cycle, for which traditional ASTM type due diligence methodologies are not practical.

This paper uses case studies involving due diligence for acquisitions in the Alberta oil reserves to illustrate a forward-looking assessment methodology for evaluating key non-technical risks such as community relations, water availability and management, sustainable risk management strategies, and reclamation planning. The case studies demonstrate how the results of the due diligence activities were incorporated into the financial models for the investment, allowing the investors to more fully understand the potential risks and opportunities associated with the acquisitions and asset development and incorporate these into their financial models.

The approaches used in these case studies represent a significant and important shift in thought processes around risk evaluation and prioritization during due diligence.
Optimizing Drilling Waste Treatment to Meet Discharge Criteria
Authors: Massam Karen , Andrade Diana , Mueller Frank
Published: June 2014

Regulations governing offshore discharge are increasingly stringent and diverse, varying between country, legislative framework and type of discharge. One major waste stream is the slop generated during the drilling operation, which is collected in the rig drain systems or in surface pits. The slops come from multiple sources, vary widely in composition and are therefore challenging to treat to meet the discharge regulations of a global market.

Slops are formed when drilling or displacement fluids, wash water from routine cleaning operations or rain water runoff become contaminated with drilling fluid components. The slops are captured, either in surface pits or through the rig drain system and collected in storage tanks. Chemical and physical treatments can be used to treat this stream to minimize the volume and cost of disposal, but due to the complex and varied nature of the slop stream, treatment methods must be tailored. Optimal solutions should treat the stream to recover and recycle any drilling fluid. Water should be separated and treated to meet the discharge criteria. In this way the total volume of waste requiring disposal can be significantly reduced.

This paper will present a review of the discharge criteria relating to drilling slop waste, highlighting the variations seen between countries. The paper will discuss how this variability, together with the slop chemical characteristics, impacts optimum treatment methods. Examples will be provided of successful treatments of a variety of slop wastes, where both chemical and physical treatment was successfully applied to meet a range of discharge criteria from oil content to complex organic analysis.

Understanding slop treatment and the multitude of discharge regulations that can be applied will permit the optimal solution for slop treatment to be selected to minimize waste and maximize reuse whilst ensuring compliance to the required environmental regulations.
Gas Transport Characteristics in Membrane Reactors for Environmental Applications
Authors: Kajama Mohammed N. , Gobina Edward
Published: June 2014

Silica composite membrane was obtained by the repeated dipping method from a 30 nm y-Al2O3 membrane. Gas permeation behaviour was obtained from the gases (N2, CO2, O2, CH4, H2, and He) at a permeation temperature of 298 K and an average pressure between (1.03 - 3.50 Pa). Single gas permeance and permeability of the membrane was calculated in this experiment. This silica composite membrane showed permeability of up to (10-7 - 10-8 mol m/m2 s-1 Pa-1) for the gases (N2, CH4, and H2) after the 5th dip at permeation temperature of 298 K. Gas permeabilities through the silica membrane followed the order of their designated molecular weight written as (H2 > CH4 > N2 > O2) which is (2 > 16 > 28 > 32 g/mol), and attributed to Knudsen flow transport mechanism. The permeance of gas molecules (N2, CO2, O2, H2, He and CH4) on the membrane was also obtained for up to three number of dippings at permeation temperature of 298 K and an average pressure of (1.15 - 1.50 Pa). However, the result shows that gas permeance decreases as the number of dipping increases. The results shows an outstanding regression fit (R2 = 0.9989, 0.9966, 0.9958, 0.9939 and 0.9925) at 2nd dip for the gas molecules (N2, CO2, CH4, H2 and O2) which also confirms Knudsen flow mechanism where the interactions of molecule-pore wall are more significant.
Analyzing Production Data From Hydraulically Fractured Wells: The Concept of Induced Permeability Field
Authors: Fuentes-Cruz Gorgonio , Gildin Eduardo , Valkó Peter P.
Published: June 2014

This work introduces a new model for the production-decline analysis (PDA) of hydraulically fractured wells on the basis of the concept of the induced permeability field. We consider the case when the hydraulic-fracturing operation—in addition to establishing the fundamental linear-flow geometry in the drainage volume—alters the ability of the formation to conduct fluids throughout, but with varying degrees depending on the distance from the main fracture plane. We show that, under these circumstances, the reservoir response departs from the uniform-permeability approach significantly.

The new model differs from the once promising group of models that are inherently related to power-law-type variation of the permeability-area product and thus are burdened by a mathematical singularity inside the fracture. The analysis of field cases reveals that the induced permeability field can be properly represented by a linear or exponential function characterized by the maximal induced permeability k0 and the threshold permeability k*. Both these permeabilities are induced (superimposed on the formation) by the hydraulic-fracturing treatment; thus, the model can be considered as a simple, but nontrivial, formalization of the intuitive stimulated-reservoir-volume (SRV) concept.

It is quite reasonable to assume that the maximum happens at the fracture face and that the minimum happens at the outer boundary of the SRV. The contrast between maximal and minimal permeability, SR = k0/k*, will be of considerable interest, and thus, we introduce a new term for it: stimulation ratio (SR). Knowledge of these parameters is crucial in evaluating the effectiveness of today's intensively stimulated well completions, especially multifractured horizontal wells in shale gas. The approach describes, in a straightforward manner, the production performance of such wells exhibiting transient linear flow and late-time boundary-dominated flow affected also by a skin effect (i.e., by an additional pressure drop in the system characterized by linear dependence on production rate).

This work provides the induced-permeability-field model within the single-medium concept, and shows that some features widely believed to require a dual-medium (double-porosity) representation are already present. Advantages and drawbacks related to applying the concept in a dual-medium approach will be discussed in an upcoming work. We present the model and its analytical solution in Laplace space. We provide type curves for decline-curve analysis, closed-form approximate solutions in the time domain, field examples, and practical guidelines for the analysis of commonly occurring production characteristics of massively stimulated reservoirs.