Simulation Studies on Biodiesel Production Process

Abstract

The simulation capabilities of software enables engineers to predict the behavior of a process using basic engineering relationships such as mass and energy balances, phase and chemical equilibrium, and reaction kinetics. With reliable thermodynamic data, realistic operating conditions and the rigorous software equipment models, one can simulate actual plant behavior. In the present study, Aspen Hysys is used as a process simulator for studying biodiesel production precesses. In process simulation, reliable and accurate property estimation methods play an important role in the solution of various simulation problems. Convergence and reliability of the simulation is heavily dependent on the fluid package selected. Hence a comparative study was carried out for various binary system for biodiesel production processes by predicting phase equilibrium using various thermodynamic models that provide an idea about which model will be able to represent the entire process in better way for various (fatty acid-alcohol, fatty acid-glycerol, alcohol-glycerol, fatty acid ester- alcohol etc) biodiesel systems. The case studies of different biodiesel production processes were used for simulative studies where the effect on results of simulated flowsheets was studied by varying certain parameters. The processes used for study includes alkali catalyst, solid catalyst, acid catalyst and super critical process. The study mainly focuses on the Jatropha oil as a feedstock for the production of biodiesel in India which is one of the promising source. A pre-simulation study was carried out to accurately predict properties for Jatropha oil and biodiesel which would be useful for simulative study. Using same feedstock various biodiesel production processes like alkali catalyst, super critical and heterogeneous solid catalyst process were studied and simulated. For all those process, technical and economical assessment was carried out to find promising production process for biodiesel where manufacturing cost of alkali process was lower and capital investment of solid catalyst process was better than other two processes. The merits and demerits of all three processes based on simulation studies were discussed. Basically, an attempt was made to develop a process which is techno-economically appealing from all three production process. Ratings of the major equipments were done and one promising process was intansified to reduce the operating cost of biodiesel production.