bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multi-Rate Mass-Transfer Dual-Porosity Modelling Using the Exact Analytical Solution for Spontaneous Imbibition
Authors: Maier Christine , Schmid Karen S. , Ahmed Mohamed , Geiger Sebastian 
Published: June 2014

Abstract
Multi-phase flow in carbonate reservoirs, which hold about half of the world’s remaining oil reserves, is strongly influenced by fractures present in the geological formations. Fractures are often the main flow conduits, leaving most of the oil behind in the low permeability rock matrix, and cause early water breakthrough. An accurate characterization of fracture flow and fluid exchange between fracture and matrix is needed to forecast oil recovery and optimise production in fracture-dominated and fracture-assisted reservoirs.
Dual-porosity simulations are traditionally used to model naturally fractured reservoirs. However, the classical dual-porosity models miss some key physics of fracture – matrix fluid exchange: (1) They tend to simplify mass transfer due to spontaneous imbibition since they typically cannot include arbitrary petro-physical properties due to e.g. wettabilities, viscosity ratios, initial water content, etc. (2) They cannot account for the fact that matrix blocks within a single simulation grid cell have various sizes and permeabilities, giving rise to different transfer rates, which should be captured by a distribution of transfer functions in each grid cell.
In this paper we present a novel multi-rate dual-porosity model. It is based on an unstructured finite element – finite volume technique, which solves the governing equations for two-phase flow fully implicitly. This allows us to represent complex large-scale geological structures (e.g., non-orthogonal faults and fracture corridors) accurately while small-scale diffuse fractures are modeled with an improved dual-porosity approach. Until recently, calculating the mass transfer between fractures and matrix blocks due to spontaneous imbibition for arbitrary petro-physical and fluid properties exactly was not possible because a general and exact transfer rate for arbitrary petro-physical and fluid properties was not known. In our new dual-porosity model we compute fracture-matrix transfer using the only known analytical and general solution of the Darcy equation including capillarity. This provides us with a generalised transfer function for arbitrary wettability, viscosity ratios, rock types, initial water content and boundary conditions. Each reservoir simulation grid block can contain multiple of these generalised transfer functions to model different matrix permeabilities and/or matrix block sizes present at the sub-grid scale.
Using a series of proof-of-concept simulations, we show that the difference in oil recovery using a standard single-rate dual-porosity model and our new multi-rate dual-porosity model cannot be neglected. This demonstrates that our proposed model with the generalised transfer function predicts oil recovery more accurately compared to a classical dual-porosity model.
Miscible and Immiscible Gas Injection for Enhancing of Condensate Recovery in Fractured Gas Condensate Reservoirs
Authors: Taheri Amir , Høier Lars , Torsæter Ole 
Published: June 2014

Abstract
Gas condensate reservoirs usually exhibit complex flow behaviors because of accumulation of condensate in the reservoir and two-phase flow of gas and condensate when the reservoir pressure drops below the dew-point. In some complicated geological systems like naturally fractured reservoirs, these complex behaviors will be more. In these systems, pressure drop response propagates in the fracture network and all the matrix blocks surrounded by fractures are influenced by pressure drop in the wellbore. This causes accumulation of large amount of condensate in the matrix blocks entire the reservoir when the pressure drops below the dew point. Usually, the accumulated condensate saturation in the matrix blocks of fractured reservoirs is lower than the critical condensate saturation that causes trapping of large amount of condensate in the matrix blocks. So selection of an efficient EOR scenario for recovering this trapped condensate is important.
In this paper, a single matrix block surrounded by fractures is used to study the performance of a fractured gas condensate system in natural depletion, miscible and immiscible gas injection. C1, N2, CO2 and stock-tank gas composition are considered as injection gases and their miscibility with condensate is studied. Also some sensitivity analyses were performed on different parameters for more accurate investigation about the effects of different parameters on performance of the fractured system in different production scenarios.
In both miscible and immiscible gas injection scenarios, the timing for injection and injection gas composition are two key parameters. In miscible gas injection case, miscibility is the main mechanism for condensate production, while in the case of immiscible gas injection scenario, vaporization of condensate by injected gas is the more efficient mechanism for condensate recovery. Gas-gas miscibility mechanism is more efficient in comparison to gas-condensate miscibility in miscible gas injection and vaporization in immiscible gas injection scenario.
The H2STORE Project - Experimental and Numerical Simulation Approach to Investigate Processes in Underground Hydrogen Reservoir Storage
Authors: Ganzer L. , Reitenbach V. , Pudlo D. , Panfilov M. , Albrecht D. , Gaupp R. 
Published: June 2014

Abstract
The objective of the H2STORE ("hydrogen to store") project is to investigate the feasibility of storing hydrogen produced from excessive wind and solar power in porous geological formations as well as the investigation of in-situ methane generation processes. H2STORE is a three-year, joint research project of the universities Jena and Clausthal and the national research centers GFZ, Potsdam in Germany and CNRS, Nancy in France started in 2012. The project is supported by international industrial partners and funded by the German national research program on "energy storage".
So far, several studies on H2 storage in salt caverns have been published and pilot projects are already established (e.g. in the U.S. and U.K.). Hydrogen storage in porous geological formations, however, has received only limited attention in the past. In contrast to salt caverns, porous formations could potentially provide very high storage capacities. Several concerns like the high hydrogen diffusivity have to be investigated as well as the potential reactions of injected hydrogen, formation fluids, and the storage complex. The aim of the project is to evaluate the feasibility of hydrogen storage in converted gas fields by comprehensive investigation of geo-hydraulic, mineralogical, geochemical and biological processes, gas mixing processes, caprock integrity and fluid transport properties of the reservoir rocks during the storage of hydrogen in porous rock formations.
The hydrogen impact on fundamental reservoir properties and mineralogy will be investigated experimentally as well as geochemical and gaseous phase mixing numerical simulations are included in the project activities of H2STORE. Industrial partners will provide site-specific rock material and experimental facilities for treatment of the samples under reservoir conditions have been designed and built as part of the research program.
The experimental results will be included in numerical reservoir simulation work comprising:
(a) Modeling of hydrogen propagation in the subsurface reservoir formation supplemented by its mixing with the residual gases, (b) Simulation of the geochemical reactions of gas mixtures with rock minerals, organic substances and formation water, and (c) Modeling of coupling of bio-dynamic processes and the processes of reactive transport in porous media. The simulations shall enable the transfer of experimental results from the laboratory to the field-scale and help formulating requirements on hydrogen storage in converted gas fields.
An overview on the concept, objectives and goals of the collaborative work will be presented, which may serve as an impulse for ongoing investigations on hydrogen and energy storage in porous underground rocks.
Characterization of Methane Emissions from Key Sources in the Natural Gas Production Sector
Authors: Ritter Karin , Emmert Amy , Shin David , Smith G. Reid , Lev-On Miriam , Shires Terri 
Published: June 2014

Abstract
Natural gas comprises almost one-fourth of all energy used in the U.S. with growing importance in the global energy mix. New production techniques, including those involving hydraulic fracturing, have enabled access to expanded energy resources and to increased natural gas based power generation, which has been credited with reducing greenhouse gas emissions in the U.S. However, in 2011, the U.S. Environmental Protection Agency introduced new calculation methods for gas wells - based on limited data - causing calculated emissions from natural gas systems to more than double in the U.S. national greenhouse gas inventories for 2009 and 2010 (submitted to the United Nations in 2011 and 2012 respectively).
To provide better data about natural gas systems, the American Petroleum Institute (API), in collaboration with America’s Natural Gas Alliance (ANGA), undertook a survey of U.S. natural gas production companies resulting in a rich data base from over 90,000 natural gas wells widely distributed among different producing regions in the U.S. This paper analyzes key findings of the API/ANGA study regarding methane sources pivotal to EPA’s assessment, including completions, workovers and gas well liquids unloading operations.
While the API/ANGA findings indicate significant potential overestimations in EPA’s assessment, they also confirm the importance of understanding the key activities and conversion factors that impact the estimation of methane emissions from natural gas production. Although improving the greenhouse gas emission estimation methods may take time, a more nuanced analysis is essential for informing public debate and facilitating decisions on natural gas use and its role in mitigating overall greenhouse gas emissions.
What Value Does HIA Offer to the O&G Sector in Europe?
Authors: Phillips Callie , Cummins Claire 
Published: June 2014

Abstract
Health Impact Assessments (HIAs) have been traditionally utilized in the context of less developed countries where communicable diseases are prevalent and where major projects, such as those related to the extractives industry can have a significant impact. However in a European context impacts from projects are less likely to result in major negative health impacts in part due to the health protection and regulatory context that prevails in the EU. This may call into question the need to conduct HIAs in a European context.
Drawing on project experience and publicly available research, this paper presents a case for HIA to be undertaken in a European context and demonstrates the value it offers in aiding our understanding of the way in which project impacts can affect public health. The paper will identify the benefits of the HIA in providing a rational framework and process for the identification and evaluation of health impacts that are relevant in the socioeconomic, environmental and cultural context and for developing evidence-based recommendations to inform health protection decision-making. The paper will conclude that whilst the health profile may vary across regions and global geographies, human health and well-being can be influenced by positive and negative effects of major projects. Health impact assessment is a requirement of projects funded by the International Finance Corporation (IFC) and of the Equator Principles and guidance has been produced by IPIECA for its members. Outside the oil and gas sector HIA is also widely practiced by the mining sector.
Journey to Zero: Aspiration Versus Reality
Authors: Ritchie Norman W 
Published: June 2014

Abstract
The E&P industry has embarked upon a "Journey to Zero" in which SPE has taken a leading role. While "Zero" is a noble and worthy philosophical goal, this paper describes several practical challenges that exist in turning this aspiration into reality with respect to defining, measuring, attaining and sustaining such a performance. A realistic and defensible definition of "Zero" is offered that bridges the gap between aspiration and operational reality which potentially has application in all organizations on a "Journey to Zero".
Best practice in managing biodiversity and ecosystem service issues in any operating environment
Authors: Pavanel Elena , Marconi Michele , Nucci Maria Estella , Palliggiano Diana , Pedroni Paola Maria 
Published: June 2014

Abstract
Oil & Gas operations occur in a range of environments with different degrees of ecological sensitivities. Operations are dependent on natural resources that biodiversity and ecosystems provide, and may also cause impacts both in the short and long term.
The Oil & Gas industry has long recognised the importance of managing interactions of its activities with the natural environment and the need to integrate biodiversity and ecosystem services (BES) into existing environmental management practices throughout the project life cycle. This is key to ensuring business continuity, the sustainable use of nature and access to new resources, which are increasingly located in sensitive, remote environments.
Over the past decade eni e&p Division, working in partnership with the leading international conservation NGO Fauna and Flora International, has developed company best practice for a timely and effective BES management within its global operations. This has been field-tested through pilot BES assessments and action plans in onshore and offshore sensitive environments (Italy, Ecuador, Norway, Alaska, Congo and Pakistan), and has led to an improved environmental management system.
The application of ecological science, emerging conservation concepts and international best practices combined with the knowledge gained from pilot assessments implemented in different operational, environmental and socio-economic conditions, has contributed to the development of a systematic approach to manage reliance and potential impacts of e&p global operations on BES.
This distinctive approach to BES management includes (i) global mapping and assessment of all sites against areas of high biodiversity value, (ii) implementation of site-specific BES assessments and action plans in operating sites ranked as high priority with respect to biodiversity, and (iii) incorporation of BES evaluations into Environmental Social and Health Impact Assessments (ESHIAs) in new operating sites.
As an example of site-specific BES assessments and action plan, this paper illustrates the experience from an in-field pilot project in Congo, with a particular focus on the importance of combining landscape-scale and site-scale surveys and assessments.
Using Incident Data as Leading Indicators in the Assessment of Major Incident Risk within JV Operations.
Authors: Smith Don , Linzi Paolo 
Published: June 2014

AbstractE&P organisations continue to strive towards improving HSE performance within their own operated activities. However, an area where there has been relatively little focus is on how Joint Venture (JV) Operators manage major incident risk within JV operations. Within these types of activities, the JV Operator is relied on to deliver the appropriate HSE performance, with the other JV partners adopting a predominately reactive approach to HSE issues that occur during the operation.Against the background of a continued drive to improve HSE performance within all its activities (both operated and non-operated) and to understand and manage its exposure to major incidents within JV operations where it is not the operator, a methodology has been developed within eni UK to provide an indicator of the major incident potential within the non-operated joint ventures the organisation is engaged in within the UK sector.The methodology is based on comparing and combining different measures of major incident risks. In particular two aspects are addressed: the estimation of major incident risk inherent in the JV operation and a measure relating to the manner in which the operator is managing the barriers required to prevent a major incident from occurring.The paper presents an overview of the methodology then focuses on the use of incident, near miss and operational (event) data as a means of assessing the integrity of the barriers required to manage major incident risk. Examples of the type of information results from the use of the event data are presented.
Non-Technical Skills and Crew Resource Management
Authors: Flin Rhona , Wilkinson Jill 
Published: June 2014

Abstract
Major accident investigations in the energy sector have highlighted the protective role of non-technical skills. These are the cognitive and social skills that complement technical skills to achieve safe and efficient performance. They include situation awareness, decision making, leadership and teamwork: skills that are influenced by performance shaping factors, such as stress and fatigue. These skills are the focus of ongoing human factors research to provide an evidence base for training in aviation and other high reliaibility industries, in the form of Crew Resource Management courses. Our behavioural research from flightdecks and operating theatres has identified key non-technical skills for airline pilots, surgeons, anaesthetists and scrub nurses. These taxonomies have been developed into observational rating systems for workplace based competence assessment of non-technical skills which are now used in a number of countries. Drawing from this research, as well as from two recently completed projects on Crew Resource Management, sponsored by the Energy Institute and OGP (Oil and Gas Producers), this paper will examine background research on non-technical skills for wells operations and optimal methods for introducing a non-technical skills approach to the energy sector. It will examine methods of indentifying key non-technical skills for target occupations and will consider emerging issues relating to Crew Resource Management training design and implementation. Professional and scientific implications of non-technical skills assessment procedures will also be discussed.
Tele-Cardiology in Remote O&G Premises
Authors: Panait Dragos , Frano Mika 
Published: June 2014

Abstract
The availability of new technologies and communication systems allowed the Corporate’s Medical Department to start the implementation of a new approach in health protection and prevention, emergency management as well as in monitoring of employees with certain health risks.
Reports analysing the repatriation cases starting with year 2006 highlighted a high percentage of pathologies related to cardiovascular system representing the main not-work related cause for early work shift interruption. In fact this group of pathologies held the first place in the top three main causes of repatriation for 5 years in a row until 2011 when finally it has been dethroned by digestive diseases pathologies group.
After implementation of Tele-cardiology, it was expected that the number of repatriations due these illness (or at least those preventable) to gradually decrease in the following years.
Persons who are considered fit for work but have a certain chronic pathology, increased level of CV risk (diabetics, Hypertensive, impaired fats metabolism, cardiopathy, obesity, post AMI, by pass surgery, etc.) and whose health should be closely monitored, are included in monitoring programs and benefit of a consultation of the world-class specialist.
Extended health monitoring of the employees during the working period, make them feel and effectively be safer from the Health point of view. Preventing the emergencies and assuring a more cost effective health management are secondary objectives none the less as important as the main goal of such prevention oriented program.
BOP Reliability monitored Real Time
Authors: Huse Jan Reier , Alme Inge A. 
Published: June 2014

Abstract
The BOP is a complex construction with multiple parts and systems integrated. Any single failure will affect the overall functionality of the BOP. A key question will always be whether a particular failure has such an adverse effect on the overall functionality that the BOP needs to be pulled for repair and hence drilling halted. The presentation will outline how a BOP is broken down into a detailed fault tree. The fault tree is modeled in the software tool RiskSpectrum® originally developed for assessing process safety of nuclear power plants. Once a failure of any part in the BOP assembly is detected, the information is fed into the model, and the effect on the overall availability of the BOP is evaluated through a predefined methodology. The results are displayed to the crew onboard through any easy to understand mimic. The operating crew onboard an offshore drilling unit can then continuously monitor the availability of the BOP and make decision on their further actions based on real time facts on BOP status.
The BOP model has been developed under a contract with and funding from a major drilling operator and Lloyd’s Register, with BOP manufacturers being directly involved. US Authorities has been kept informed on the development. A joint industry panel with representative from Mobile Drilling Unit Owners, BOP manufacturers and Operating Companies has been overseeing the work.
The model has been launched and training of the operators has been carried out. Results from the implementation will be available at the presentation at the conference.
Developing Operational Procedures for Safe and Efficient Application of New Process Control Functionality on the Drilling Rig
Authors: Iversen F. P , Daireaux B.. , Leulseged A.. , Mihai R. G. , Gressgaard L. J. , Bergerud R.. , Bruun B. T. , Balov M. K. 
Published: June 2014

Abstract
Introducing new control functionality on the drilling rig has an effect on handling of machinery and controls and on the overlying work process both on the rig and for off-site support. New operational procedures taking these factors into account are therefore required to ensure safe and efficient application of such new technology.
This paper presents a new method for developing operational procedures for the driller when applying a system for automatic safeguarding and optimization of pump and pipe control in drilling operations. This method has been developed and subsequently applied through a lengthy study. A laboratory test environment has been used for this purpose, containing an advanced drilling simulator with the safeguarding and optimization functionality integrated.
The method applied consists of three phases, all performed in the laboratory test environment. Initially, the measurable effect of use of the system on the driller’s performance was evaluated in detail, using a set of test cases and a series of test-personnel from a drilling contractor. Subsequently the ability to drill a well section with incorporated incidents and exceptions was studied. Finally, operational procedures were developed in cooperation with the test-personnel, again using the test environment for testing and checking of procedures.
In this development process the focus has been on varying system modes and on handling of system and drilling process exceptions, while taking into account the effect of human factors and the wider organizational context of work conduct.
The authors believe that the method described is a suitable way to develop procedures for application of new control functionality on the drilling rig, and would recommend that such studies should be performed for new technologies to be applied in control of drilling operations.