Article

Integration of Recursive Operability Analysis, FMECA and FTA for the Quantitative Risk Assessment in biogas plants: Role of procedural errors and components failures

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Abstract

With more than 350 GWh per year and thousands of installations around the world, biogas is an appealing strategy in the field of energy production and industrial waste optimization. In this sense, it is of paramount importance to address the risk associated with such plants, as an increasing trend of accidents have been recorded in the last 20 years. In this work, a representative biogas production plant was considered, and a risk assessment was carried out through the combination of Recursive Operability Analysis and Failure Mode and Effects Criticality Analysis. The methodology is rigorous and allows for both the identification and the quantification of accidental scenarios due to procedural errors and equipment failures, which miss in the literature for the case of biogas. The analysis allows the automatic generation of the Fault Trees for the identified Top Events, which can be numerically solved. Results show that the most critical accidental scenario in the biogas plant here considered is the formation of an explosive air-biogas mixture, which can occur in both anaerobic digester and condensate trap. The calculated probabilities agree with the results available in literature on similar plants. Pumps and Distributed Control System were found to be the most critical components.

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... Then, the minimal cut and path sets and the occurrence probability of the top event [11] can be determined. Structure importance (SI) [15], probability importance (PI), critical importance (CI) [30], Fussell-Vesely importance (FVI) [14], and the proposed Fussell-Vesely-Xu importance (FVXI) can be determined based on the structure of the fault tree and the occurrence probability of basic and top events. FVI and FVXI can be calculated with the help of a Bayesian network [31][32][33]. ...
... Probability importance refers to the impact of the occurrence probability of basic events on the occurrence probability of the top event [30]. Probability importance is a type of Birnbaum importance and can be calculated as follows: ...
... Critical importance refers to the variation rate of the occurrence probability of the top event caused by the variation rate of the occurrence probability of basic events [30]. Critical importance can be calculated as follows: ...
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Background: Although hydraulic support can help enterprises in their production activities, it can also cause fatal accidents. Methods: This study established a composite risk-assessment method for hydraulic support failure in the mining industry. The key basic event of hydraulic support failure was identified based on fault tree analysis and gray relational analysis, and the evolution mechanism of hydraulic support failure was investigated based on chaos theory, a synthetic theory model, and cause-and-effect-layer-of-protection analysis (LOPA). Results: After the basic events of hydraulic support failure are identified based on fault tree analysis, structure importance (SI), probability importance (PI), critical importance (CI), and Fussell-Vesely importance (FVI) can be calculated. In this study, we proposed the Fussell-Vesely-Xu importance (FVXI) to reflect the comprehensive impact of basic event occurrence and nonoccurrence on the occurrence probability of the top event. Gray relational analysis was introduced to determine the integrated importance (II) of basic events and identify the key basic events. According to chaos theory, hydraulic support failure is the result of cross-coupling and infinite amplification of faults in the employee, object, environment, and management subsystems, and the evolutionary process has an obvious butterfly effect and inherent randomness. With the help of the synthetic theory model, we investigated the social and organizational factors that may lead to hydraulic support failure. The key basic event, jack leakage, was analyzed in depth based on cause-and-effect-LOPA, and corresponding independent protection layers (IPLs) were identified to prevent jack leakage. Implications: The implications of these findings with respect to hydraulic support failure can be regarded as the foundation for accident prevention in practice.
... The contribution shows that the proposed model allows a good assessment of reliability and provides excellent fault analysis. Two traditional methods: FT and FMECA are combined to another traditional method to determine critical component in a diesel generator [11], they have also been utilized for conducting quantitative analyses of biogas plants by integrating them with recursive operability analysis, with a focus on elucidating the roles of procedural errors and component failures [12]. In other contributions, such as a maintenance plan for a turbine of hydroelectric power plant, Reliability-Centered Maintenance (RCM) was combined with FMECA [13] to better understand all potential failure scenarios that can affect industrial machines, while ensuring their reliability. ...
... A priori and a posteriori probabilities of the basic events(1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16) ...
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... We repeat the procedure for every failure mode. To simulate the probability of a top event failure mode, many authors have used the Monte Carlo method (Baraldi et al., 2010;da Costa et al., 2020;Markulik et al., 2021b;Zio & Pedroni, 2010;Zonouz & Miremadi, 2006), the critical cuts method (Barozzi et al., 2021;Hu et al., 2021;Xu et al., 2021). ...
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Fault Tree Analysis (FTA) is a method that directly focuses on the modes of failures. The FTA is a graphical representation of the major faults or critical failures associated with a product, as well as the causes for the faults and potential countermeasures. The aim of this research paper is to calculate the probability of the top event – the failure of the process using FTA and propose a technique to prioritize factors for action design and reduce the likelihood of a top event failure based on manufacturers' requirements. We have constructed a qualitative fault tree to produce office components packed and sealed in blister packs using a KOCH KBS-PL machine. We defined the top event G – the production of office components, packed and sealed in blister packs on the machinery KOCH KBS-PL. Then we defined events leading to top events down to individual failure factors. Based on the links between the fault tree and the probability of failure, we performed a quantitative analysis to determine the probability of failure of individual events. We found out that the probability of failure of G is 5.04%. Subsequently, we identified which factors most significantly reduce the resulting probability of failure of factor G. These are the factors: E – feed rate, F – cooling, AL – incorrect setting and D – break. It has been proven that by controlling these 4 factors, we can reduce the probability of failure of top event G to 2.36%, provided that effective measures are taken. The final proposal meets the requirements of several manufacturers for a fast, efficient, and cost-effective solution. We have created a proposal that saves time, has minimal software and hardware requirements, and is easy to use. The efficiency and effectiveness of the proposal was that we identified the weakest points in the fault tree that most significantly cause the top event to fail. This prioritized the factors for the design of the measures.
... The combination of these two methods can reduce the drawbacks of each method if the FTA is used to determine the root causes and the FMEA is applied to specify the severity, occurrence, and detection numbers [24] . FMEA and FTA, Recursive Operability Analysis were used for quantitative risk assessment to identify the most critical parts of the process and plant [25] . FMEA method was also developed with multiple failure analysis and the weighted priority numbers due to the weights of the three factors (S, O, D) are not equal. ...
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... Numerous studies have been conducted that prove the advantages of this technology (Kaur et al. 2021;Bai et al. 2022;Wang et al. 2021;Caetano et al. 2022;Rouhollahi et al. 2020). In the construction of cogeneration plants using biogas for livestock farms, decisions related to the choice of a specific technology and the availability of raw material (animal waste) on a significant scale are of crucial importance (Ardebili 2020;Kozłowski et al. 2019; Barozzi et al. 2021;Pryshliak et al. 2022;Doseva and Chakyrova 2019). This is done in order to ensure the smooth operation of the facility. ...
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... Li 3 the necessity to identify the potential root causes in the system and analyze the critical situation in order to determine the maintenance operations required based on the reliability-centered maintenance and radical maintenance approaches using the FTA and failure mode effect and criticality analysis (FMECA) methods. In addition, the FTA approach is adopted to evaluate the reliability of systems and analyze the probability of failure occurrence [2]. Barozzi et al. in the paper, a representative biogas production plant was considered, and a risk assessment was carried out through the combination of Recursive Operability Analysis and Failure Mode and Effects Criticality Analysis (FMECA). ...
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... Quantitative methods used in the literature can be analytical (such as the probability of failure POF, second-order reliability method SORM), probabilistic (Monte-Carlo simulation MCS, stochastic response surface methods SRSM), or sophisticated (fuzzy set theory FST, multi-criteria decision analysis MCDA) [61]. Those reliability-based methods are then categorized into FM analyses (FMEA), tree and diagrammatic analyses [62][63][64][65] (FTA, DFT, ETA, and BT), and hazard analyses (HAZOP). Ref. [66] contains further details of risk assessment methods. ...
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... Using dynamic Bayesian networks (DBN) and support vector regression (SVR) methods, Han et al. (2021) proposed a new hybrid dynamic risk modeling strategy for critical equipment in offshore facilities. For risk assessment of biogas facilities, Barozzi et al. (2021) used FTA, FMECA, and Recursive Operability Analysis. ...
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This paper examines the requirements that might reasonably be regarded as being implied by the ALARP principle. The principle stipulates that those responsible should reduce risks of death and injury for workers and members of the public to levels that are ‘As Low As Reasonably Practicable’. The main aim of the paper is to resolve the apparent conflict between the ALARP principle on the one hand and, on the other, conventional social cost–benefit analysis. In particular, cost–benefit analysis prescribes that a safety improvement should be undertaken only if the cost of doing so is less than or equal to the resultant benefits, whereas some regulatory agencies interpret ALARP as requiring that the improvement must be undertaken provided that costs are not in ‘gross disproportion’ to benefits, which would clearly include cases in which costs might substantially exceed benefits.
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A methodology has been developed to conduct probabilistic fault tree analysis during risk assessment in chemical process industries. The methodology is based on a system involving (a) development of fault tree, (b) determination of minimum cutsets or shortest pathways leading from initiating events (malfunctioning) to the top event (the major accident), (c) probability analysis, and (d) working out improvement index values. To this end techniques of Boolean algebra, structure moduling, analytical method of cutsets finding (top‐to‐bottom algorithm), Monte‐Carlo simulation, optimization technique and fuzzy probability set have been used. We named the methodology Analytical ‐Simulation Methodology (ASM) and we developed a software package PROFAT (PRObabilistic fault tree analysis) to facilitate the use of the methodology in a rapid and eflective, yet user‐friendly manner. PROFAT enables the user to find out, in an industry, (i) initiating events which may eventually lead to a major accideizt, (ii) shortest routes (minimum cutsets) a series of initiating events may take place while aiding each other in causing the accideizt. (iii) the probabilities of occurrence of such initintirig events, (iv) relative contributiom of each of the initiating events and, finally, (v) identfiing initiating events with the greatest potential to cause the top event (major accident) so that accident prevention strategies aud emergency preparedness plans can be focused on them. The noteworthy attributes of the system are: resilience towards lack of precision in the basic data, swift processing with moderate requirements of computation cupacity (sophistication of computers needed), ease of use, and direct1y utiliz‐able output. The applicability of PROFAT has been denionstrated with a case study of a sulfolane manufacturing unit.
Article
This paper describes the utilization of the Recursive Operability Analysis for the identification of accident scenarios of a pilot plant gasifier fed with solid wastes and alternative fuels. The procedure was used for the identification of situations of potential risk during the operation of the plant and, coupled with the Fault Tree algorithm, in the successive quantification of probability of occurrence of the different potential Top Events. The results indicated that Recursive Operability Analysis can be usefully applied in the design as well as in the commissioning and in the start-up stages of the plant construction. The quantification of the actual effects of the implementation of new management criteria and design solutions can also be easily obtained.
Article
Understanding reliability parameters and costs -- Interpreting failure rate -- Predicting raliability and risk-- Achieving reliability and maintainability -- Legal, management and safety considerations
Article
Sumario: Hazard, accident and loss -- Legislation and law -- Major hazard control -- Economics and insurance -- Management and management systems -- Reliability engineering -- Hazard identification -- Hazard assessment -- Plant siting and layout -- Process design -- Pressure system design -- Control system design -- Human factors and human error -- Emission and dispersion -- Fire -- Explosion -- Toxic release -- Plant commissioning and inspection -- Plant operation -- Plant maintenance and modification -- Storage -- Transport -- Emergency planning -- Personal safety -- Accident research -- Information feedback -- Safety systems -- Computer aids -- Artificial intelligence and expert systems -- Case histories -- Flixborough -- Seveso -- Mexico city -- Bhopal -- Pasadena -- Canvey Reports -- Rijnmond report -- Laboratories -- Pilots plants -- Safety, health and the environment -- Noise -- Failure and event data -- Earthquakes -- San Carlos de la Rapita -- ACDS transport hazards -- Offshore -- Piper Alpha -- Nuclear energy -- Three Mile Island -- Chernobyl -- Rassmussen report -- ACMH model licence conditions -- HSE guidelines on developments near major hazards -- Public planning inquiries -- Standards and codes -- Institutional publications -- Information sources -- Units and unit conversion Bibliografía: 503 p. del vol. 3
Article
Centralized biogas plants in Denmark codigest mainly manure, together with other organic waste such as industrial organic waste, source sorted household waste, and sewage sludge. Today 22 large-scale centralized biogas plants are in operation in Denmark, and in 2001 they treated approx 1.2 million tons of manure as well as approx 300,000 of organic industrial waste. Besides the centralized biogas plants there are a large number of smaller farm-scale plants. The long-term energy plan objective is a 10-fold increase of the 1998 level of biogas production by the year 2020. This will help to achieve a target of 12-14% of the national energy consumption being provided by renewable energy by the year 2005 and 33% by the year 2030. A major part of this increase is expected to come from new centralized biogas plants. The annual potential for biogas production from biomass resources available in Denmark is estimated to be approx 30 Peta Joule (PJ). Manure comprises about 80% of this potential. Special emphasis has been paid to establishing good sanitation and pathogen reduction of the digested material, to avoid risk of spreading pathogens when applying the digested manure as fertilizer to agricultural soils.
Article
Biogas, a clean and renewable form of energy could very well substitute (especially in the rural sector) for conventional sources of energy (fossil fuels, oil, etc.) which are causing ecological-environmental problems and at the same time depleting at a faster rate. Despite its numerous advantages, the potential of biogas technology could not be fully harnessed or tapped as certain constraints are also associated with it. Most common among these are: the large hydraulic retention time of 30-50 days, low gas production in winter, etc. Therefore, efforts are needed to remove its various limitations so as to popularize this technology in the rural areas. Researchers have tried different techniques to enhance gas production. This paper reviews the various techniques, which could be used to enhance the gas production rate from solid substrates.
From HazOp study to automatic construction of cause consequence diagrams for frequency calculation of hazardous plant states
  • P M Contini
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Contini, P.M., Contini, S., Copelli, S., Rota, R., Demichela, M., 2015. From HazOp study to automatic construction of cause consequence diagrams for frequency calculation of hazardous plant states. In: Presented at the Safety and Reliability of Complex Engineered Systems -Proceedings of the 25th European Safety and Reliability Conference, pp. 347-355.
Chemical process safety: fundamentals with applications
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Crowl, D.A., Louvar, J.F., 2002. Chemical process safety: fundamentals with applications. In: Prentice-hall International Series in the Physical and Chemical Engineering Sciences, second ed. Prentice Hall PTR, Upper Saddle River, N.J.
Explosion in biogasanlage
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Daller, T., 2011. Explosion in biogasanlage [WWW document], 12.20.20. https://www. sueddeutsche.de/muenchen/erding/eichenried-explosion-in-biogasanlage-1.1004029.
Managing process safety in the age of digital transformation
  • Jones
Jones, S., 2019. Managing process safety in the age of digital transformation. Chem. Eng. Trans. 77, 619-624. https://doi.org/10.3303/CET1977104.
European commission, joint research centre, institute for the protection and the security of the citizen
  • Matuzas
Matuzas, V., Contini, S., 2012. European commission, joint research centre, institute for the protection and the security of the citizen. In: ASTRA Plus User Manual: Description of How to Use the Modules for Fault Tree Analysis and Concurrent Importance and Sensitivity Analysis. Publications Office, Luxembourg.
From HazOp study to automatic construction of cause consequence diagrams for frequency calculation of hazardous plant states
  • Contini