Bow Tie Methodology for Risk Assessment in Petroleum Storage Facilities: A Case Study in Cameroon

Abstract

Introduction: Oil storage facilities play an important role in energy security and economic development in industrializing countries like Cameroon. However, these infrastructures, often aging and located in areas subject to increasing climate stress, pose significant industrial risk sources.

Objectives: This study presents an innovative application of the butterfly knot method for the assessment of industrial risks in oil storage facilities in Cameroon.

Methods: Combining probabilistic risk modeling, analysis of the effectiveness of safety barriers, and a multicriteria approach (MCA), this methodology addresses the shortcomings of traditional qualitative approaches.

Results: The framework incorporates the impacts of climate change and specific sociotechnical factors in sub-Saharan Africa. A case study on the tanks of the SONARA refinery (Limbe-Cameroon) during the period from 2018 to 2023 demonstrates the method's ability to prioritize critical scenarios and optimize mitigation strategies. The results reveal that the risks of fire/explosion (probability: 2.3×10⁻⁴/year) and groundwater contamination (severity index : 8.7/10) dominate, with 40% of existing barriers deemed inadequate under extreme climatic conditions, extreme climate impacts (RCP 8.5), and a reduced lifespan of tanks by 4.5 years under humidity >85%.

Conclusions: This research is based on an in-depth case study of the reservoirs of the SONARA refinery in Limbe, Cameroon, a strategic yet vulnerable site located in close proximity to residential areas and the Atlantic Ocean.