Fuel and Combustion

Fuel and Combustion

Fire Risk Assessment of Diesel Fuel Storage Tanks in Mashhad Power Plants Using the Bow-Tie Technique and the Development of Appropriate Control and Mitigation Measures

Document Type : Original Article

Authors
Department of Natural Resources and Environment, SR.C., Islamic Azad University, Tehran, Iran
Abstract
In this study, fires in diesel storage tanks at power plants were analyzed as a primary event. Initially, the main causes of the event were identified and assessed using the Fault Tree Analysis (FTA) method. Subsequently, the potential consequences of the event were predicted through the Event Tree Analysis (ETA) technique. Finally, the incident pathway—from the cause phase to the consequence phase—was illustrated and examined using the Bow Tie diagram. Moreover, the most important control measures for preventing fuel tank fires and mitigating their consequences were recommended in order of priority. In total, five main threats, along with 79 sub-causes and intermediate events, were found to contribute to fires in diesel storage tanks at power plants. Fifty-two control measures (barriers) were identified and proposed to prevent the occurrence of such fires. Additionally, five primary safety, economic, and environmental consequences of tank fires were identified, and the most important control measures to mitigate these consequences were recommended. The analysis of the results and the illustrated diagrams revealed that the most important control measures for preventing fires in diesel storage tanks, in order of priority, are: the development and strict adherence to safety procedures, the provision of necessary training, and regular maintenance and servicing. Moreover, the key measures for mitigating the consequences of fuel tank fires include: enhancing fire suppression systems, timely activation of existing fire suppression systems, prompt firefighting, conducting periodic drills, and fuel replacement

Highlights

This study employed a qualitative Bow-Tie analysis approach to assess fire scenarios involving diesel storage tanks at a selected power plant as a case study. The results demonstrated that, by integrating Fault Tree Analysis and Event Tree Analysis, this method enables the systematic identification of threats, the top event, consequences, and control barriers, and can serve as an effective tool for supporting decision-making in process risk management. Analysis of the accident pathways indicated that a considerable proportion of the intermediate events were associated with human and managerial factors, including deficiencies in the implementation of safety procedures, inadequate training, shortcomings in preventive maintenance programs, and insufficient supervision. This finding was derived from the analysis of hazard scenarios, the frequency of intermediate events, and the judgement of the expert team, and highlights the central role of human and managerial factors in the development and control of risk. Furthermore, the application of engineering barriers, such as fixed fire-extinguishing systems, fire detection and alarm systems, earthing and bonding systems, leak monitoring, and emergency response programs, plays an important role in reducing the likelihood of accident occurrence or limiting the consequences of an incident.

Keywords
Subjects

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