Browsing by Author "Animah, Isaac"

Now showing 1 - 7 of 7
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    Condition assessment, remaining useful life prediction and life extension decision making for offshore oil and gas assets
    (Elsevier, 2017-05-04) Animah, Isaac; Shafiee, Mahmood
    Offshore oil and gas assets are highly complex structures comprising of several components, designed to have a lifecycle of about 20 to 30 years of working under harsh operational and environmental conditions. These assets, during their operational lifetime, are subjected to various degradation mechanisms such as corrosion, erosion, wear, creep and fatigue cracks. In order to improve economic viability and increase profitability, many operators are looking at extending the lifespan of their assets beyond the original design life, thereby making life extension (LE) an increasingly critical and highly-discussed topic in the offshore oil and gas industry. In order to manage asset aging and meet the LE requirements, offshore oil and gas operators have adopted various approaches such as following maintenance procedures as advised by the original equipment manufacturer (OEM), or using the experience and expertise of engineers and inspectors. However, performing these activities often provides very limited value addition to operators during the LE period of operation. This paper aims to propose a systematic framework to help operators meet LE requirements while optimizing their cost structure. This framework establishes an integration between three individual life assessment modules, namely: condition assessment, remaining useful life (RUL) prediction and LE decision-making. The benefits of the proposed framework are illustrated through a case study involving a three-phase separator system on a platform which was constructed in the mid-1970s in West Africa. The results of this study affirm the effectiveness of this framework in minimizing catastrophic failures during the LE phase of operations, whilst ensuring compliance to regulatory requirements.
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    Decision support methods and applications in the upstream oil and gas sector
    (Elsevier, 2018-10-17) Shafiee, Mahmood; Animah, Isaac; Alkali, Babakalli; Baglee, David
    Decision-making support (DMS) methods are widely used for technical, economic, social and environmental assessments within different energy sectors, including upstream oil and gas, refining and distribution, petrochemical, power generation, nuclear power, solar, biofuels, and wind. The main aim of this paper is to present a comprehensive literature review and classification framework for the latest scholarly research on the application of DMS methods in the upstream oil and gas industry. To achieve this aim, a systematic review is conducted on the current state-of-the-art and future perspectives of various DMS methods applied to different upstream operations (such as exploration, development and production) which take place prior to shipping of crude oil and natural gas to the refineries for processing. Journal and conference proceeding sources that contain literature on the subject are identified, and based on a set of inclusion criteria the related papers are selected and reviewed carefully. A framework is then proposed to classify the literature according to the year and source of publications, type of fossil fuel sources, stages of oil and gas field lifecycle, data collection techniques, decision-making methods, and geographical distribution and location of case studies. The proposed literature classification and content analysis can help upstream oil and gas industry stakeholders such as field owners, asset managers, service providers, policy makers, environmentalist, financial analyst, and regulatory agencies to gain better insight about their business activities with well-informed decision-making processes.
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    Development of a techno-economic framework for life extension decision making of safety critical installations
    (Elsevier, 2016-09-22) Shafiee, Mahmood; Animah, Isaac; Simms, Nigel J.
    One of the major decisions in management of the industrial assets is to ensure the feasibility of life extension process for safety critical components when they reach end-of-life. Most of the existing life extension decision-making models are restricted solely to either “technical” or “economic” feasibility analyses that may lead to inaccurate results or incorrect conclusions. In this paper, a comprehensive life extension feasibility assessment framework by taking into account both the technical and economic considerations is developed. The proposed techno-economic model for life extension of safety critical elements consists of three phases: preparation, assessment, and implementation. The technical assessment part of the framework incorporates all aspects of data collection and review, screening and prioritization of safety critical elements, condition assessment, estimation of remaining useful life, and risk analysis, while the economic assessment part deals with cost-benefit analysis. The decision to qualify a safety critical element for continuous operation beyond its service life is made based on a “life extension measure (LEM)” which is calculated by combining two indexes of “equipment health condition” and “economic added-value” obtained respectively from the technical and economic assessments. The model is applied to support the life extension decision-making procedure for water deluge systems in offshore oil installations. The results of the study show that the model is highly capable of assisting asset owners to evaluate the technical and economic benefits of extending the service life of components.
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    Life extension decision making of safety critical systems: An overview
    (Elsevier, 2017-03-16) Shafiee, Mahmood; Animah, Isaac
    In recent years, the concept of “asset life extension” has become increasingly important to safety critical industries including nuclear power, offshore oil and gas, petrochemical, renewable energy, rail transport, aviation, shipping, electricity distribution and transmission, etc. Extending the service life of industrial assets can offer a broad range of economic, technical, social and environmental benefits as compared to other end-of-life management strategies such as decommissioning and replacement of equipment. The aim of this paper is to present a comprehensive literature review and classification framework for academic research and industrial practices related to life extension of safety critical systems and installations. To achieve this, a systematic review is performed on the current state-of-the-art and new developments in the field of asset life extension in various industries. Major sources from which the literature can be gathered are identified and some assessment criteria are defined to categorize the selected publications. A classification framework is then proposed to support life extension decision making process with respect to the type of asset and industry sectors where the concept of life extension has been of interest, condition assessment techniques used for qualification of assets for life extension, life prediction models, life extension strategies, etc. The current key issues in relation to the subject are outlined and the strengths and weaknesses of existing life extension decision-making tools are highlighted. This review contains an exhaustive list of scientific references on the topic, including articles published in journals, industry magazines, books and conference proceedings, university dissertations, technical reports and government documents. The proposed literature classification and analysis can help asset owners, asset managers, service providers, stakeholders, public policy-makers, environment protection authorities, and regulatory bodies gain valuable insights on asset life extension decision-making procedures and methodologies.
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    Managing life extension process for safety critical elements on offshore oil and gas installations
    (Cranfield University, 2017-05) Animah, Isaac; Shafiee, Mahmood; Simms, Nigel J.
    Life extension (LE) of Safety Critical Elements (SCEs) is one of the hottest topics in the offshore Oil and Gas (O&G) industry today. Although LE is considered as the most appropriate alternative among the end of life management strategies (EOMLS), there are still several challenges confronting asset managers during LE phase of operation. Key among these challenges includes; lack of integrated technical and economic approach to assess the current health conditions of SCEs for LE, over reliance on expert knowledge and experience for selecting the most suitable LE strategy and the lack of suitable approach to integrate all LE decision making elements for effective operations of SCEs. To overcome these challenges, this research aimed at developing an integrated decision making framework to use for managing LE process for SCEs found on offshore O&G installations. In order to overcome the first challenge, a techno- economic framework which integrates technical and economic assessment procedures for condition assessment of SCEs is developed. Furthermore, approaches based on Life Cycle Cost Benefit (LCCB) concept and Multi Criteria Decision Making (MCDM) method are subsequently proposed to overcome the challenge of lack of suitable methodology for selecting the most appropriate LE strategy. Lastly, a proposed multi-stage remanufacturing architecture capable of integrating all LE decision making elements is developed. These decision making models have been developed and analysed using data from literature review, expert opinion, review of company internal documents as well as data from manufacturers of SCEs in the offshore O&G industry. The models are validated with a number of real life case studies which involves water deluge system, industrial air compressors and three phase separation systems to ascertain their efficacy. The outcome of validation processes indicates that these decision making models provide cost effective solutions to overcome the three key LE challenges outlined in this study. This research has added to the scientific understanding of this research area through creation of novel decision making models to support LE phase of operation in the offshore O&G industry.
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    A multi-stage remanufacturing approach for life extension of safety critical systems
    (Elsevier, 2017-03-02) Animah, Isaac; Shafiee, Mahmood; Simms, Nigel J.; Tiwari, Ashutosh
    Life extension of safety critical systems is gaining popularity in many industries due to the increasing demand in world's energy consumption and the strong desire to reduce carbon emissions by different countries. Identification and implementation of a suitable life extension strategy enables safety critical systems to perform their intended functions under stated condition for an extended period of time beyond original design life. In the past, the viability analysis of life extension strategies has been undertaken based on the accumulated knowledge and experience of Original Equipment Manufacturer (OEM), maintenance engineers and inspectors. These approaches involving expert judgement are qualitative in nature and based on conservative assumptions, which may lead to inaccurate conclusion or misleading recommendations to asset managers. Therefore, it is crucial to develop an approach consisting of methods to determine the technical condition of components, estimate the cost of life extension interventions and to analyze carbon footprints. “Remanufacturing” is considered as a suitable end-of-life strategy that can help reduce the overall environmental burden from the product by processing waste materials while at the same time keeping reliability high. Due to the advantages of remanufacturing, it is widely applied for life extension purposes in safety critical industries such as offshore oil and gas, nuclear power, petrochemical, renewable energy, rail transport, aviation, shipping, and electricity distribution and transmission. In this paper, a multi-stage approach is presented to analyze the impact of remanufacturing of safety critical systems on the performance of industrial operations in terms of total cost and carbon footprint. In this approach, the equipment health status is determined by modelling the degradation of the system and then the maintenance costs and carbon footprint are calculated. For the purpose of clarity, the proposed model is applied to an air compressor system and the results are discussed.
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    Selection of the most suitable life extension strategy for ageing offshore assets using a life-cycle cost-benefit analysis approach
    (2018-08-13) Animah, Isaac; Shafiee, Mahmood; Simms, Nigel; Erkoyuncu, John Ahmet; Maiti, Jhareswar
    Purpose A substantial number of production assets in the offshore oil and gas industry are facing operation beyond their anticipated design life, thus necessitating a service life extension program in the future. Selection of the most suitable strategy among a wide range of potential options to extend the lifetime of equipment (e.g. re-using, reconditioning, remanufacturing, refurbishing and adding on safety/process control measures) remains a challenging task that involves several technical, economic and organizational complexities. In order to tackle this challenge, it is crucial to develop analytical tools and methods capable of evaluating and prioritizing end-of-life strategies with respect to their associated costs and quantifiable benefits. The paper aims to discuss these issues. Design/methodology/approach This paper presents a life-cycle cost-benefit analysis approach to identify the most suitable life extension strategy for ageing offshore assets by taking into account all the capital, installation, operational, maintenance and risk expenditures during the extended phase of operation. The potential of the proposed methodology is demonstrated through a case study involving a three-phase separator vessel which was constructed in the mid-1970s. Findings The results from the application case indicate that the capital expenditure (CapEx) accounts for the largest portion of life cycle cost for the replacement strategy, while risk expenditure (RiskEx) is the major contributor to costs associated with life extension. A sensitivity analysis is also conducted to identify factors having the greatest impact on the optimum life extension solution, including oil price, production rate and money interest rate. Practical implications In the past, the decisions about life extension or replacement of in-service equipment were often made in a qualitative way based on experience and judgment of engineers and inspectors. This study presents a “quantitative” framework to evaluate and compare the costs, benefits and risks associated with life extension strategies and subsequently to select the best strategy based on benefit/cost ratios. Originality/value To the best of authors’ knowledge, no studies before have applied life cycle assessment and cost-benefit analysis methods to prioritize the potential life extension strategies in the oil and gas industry sector. The proposed approach not only assists decision makers in selecting the most suitable life extension strategy but also helps duty holders reduce the costs corresponding to life extension execution.