Biodiesel Production by Reactive Flash: A Numerical Simulation

Reactive flash (RF) in biodiesel production has been studied in order to investigate steady-state multiplicities, singularities, and effect of biodiesel quality when the RF system approaches to bubble point. The RF was modeled by an index-2 system of differential algebraic equations, the vapor split (phi) was computed by modified Rachford-Rice equation and modified Raoult's law computed bubble point, and the continuation analysis was tracked on MATCONT. Results of this study show the existence of turning points, leading to a unique bubble point manifold, (chi(Biodiesel), T) = (0.46, 478.41 K), which is a globally stable flashing operation. Also, the results of the simulation in MATLAB (R) of the dynamic behavior of the RF show that conversion of triglycerides reaches 97% for a residence time of 5.8 minutes and a methanol to triglyceride molar flow ratio of 5:1.