Inherent safety assessment of biodiesel production: flammability parameter

Abstract

This paper discussed the inherent safety assessment of biodiesel production pathways from the perspective of flammability parameter. The NuDIST technique for flammability scores calculation is used in the case study. Ranking between the productions pathways involved was calculated by considering all chemicals in the route as a mixture instead of individual components. Aside from that, mass fractions of the chemicals involved were used as weightage factor in order to determine the main contributors to the largest hazards in the process route. Four biodiesel production pathways were used as case study. According to the inherent safety assessment done, the acid-catalyzed transesterification using fresh vegetable oil (PP4) pathway is the most hazardous route with the highest assessment score of 15.59 while the enzymatic transesterification using fresh vegetable oil (PP2) pathway is the safest route with the lowest assessment score of 1.39 in term of flammability parameter. The case study shows that the amount of chemicals existed in the process as well as their flammability characteristic, plays an important roles in determining the main contributors to the largest hazards in the route. In this work, mass fractions for every chemical were used as the weightage factor which helps in identifying the main contributors to hazards with more accuracy. A chemical with high flammability score but existed in low amount in the process might not be as hazardous as a chemical with low flammability score but existed in huge amount in the process as shown by methyl oleate and methanol in the base-catalyzed transesterification using fresh vegetable oil (PP3).