فاطمه رشيدي

The rise in global temperature caused by the combustion of fossil fuels in engines led to the use of clean fuels. Biodiesel production is increasing rapidly due to it's useful features, such as its ability to be extracted from vegetable oils, its low pollution production, and its compatibility with diesel engines. Despite the simplicity of the biodiesel production process, it involves potentially hazardous chemical reactions and hazardous materials, which can result in explosions and fires that cause equipment damage, severe injuries, and even death. So In the present study, a quantitative risk assessment was conducted by identifying hazard of the a biodiesel production unit using the HAZOP method and eva‎luating the probability of loss of contaiment and its consequences using Bow-tie analysis. Based on the findings of the quantitative eva‎luation, by applying the hazop recommendations, the probability of the occurrence of a process event was reduced by about 90%. Then, by combining the Bayesian network and fuzzy logic, dynamic risk assessment was done on the unit, the limitation of common quantitative analyzes were covered, and the uncertainty in modeling and input data was reduced. By implementing HAZOP recommendations, the average probability of process events was reduced by approximately 90 percent. also Using important measures, a sensitivity analysis was conducted. The sensitivity analysis revealed that the reactor pressure sensor, safety valves, and tower level sensor are the most crucial equipment. the result of sensitivity analysis leads to some suggestions to increase the equipment's reliability and redundancy. Modifying the Bayesian network using suggestions that obtained from sensitivity analysis, on average, reduced the probability of events by 95% Keywords:

ارزيابي ريسك ديناميك , شبكه بيزين , منطق فازي , آناليز بوتاي , تحليل درخت خطا , HAZOP

dynamic risk assessment , Bayesian Network , fuzzy logic , Bowtie analysis , Fault Tree Analysis , HAZOP

Fateme Rashidi

Dr. Sobati - Dr. Baradaran