Simulation and Optimization of Biodiesel Production from Castor Oil for Energy Reduction and Improved Process Efficiency

Abstract

This study investigates the simulation, optimization, and economic evaluation of biodiesel production from castor oil through transesterification in a continuous process. The biodiesel production line was first simulated using Aspen HYSYS, and key operating parameters and equipment specifications were subsequently optimized to enhance process efficiency and reduce production costs. Economic assessments were then carried out based on simulation outcomes and relevant financial data. Results show that increasing the number of trays in the first distillation column from 3 to 10 improves ethanol purity from 0.9988 to 0.9998 and raises its mass flow rate from 287.5 to 390 kg/h. Additionally, optimizing the water feed rate to the extraction column increases biodiesel production from 956.4 to 1036 kg/h while maintaining high product purity. Adjusting the bottom product flow rate of the second distillation column also enables achieving the target glycerol purity of 96.68%. Furthermore, Economic analysis demonstrates that the proposed optimizations increase the annual profit from biodiesel production from about $159,600 to nearly $691,100, equivalent to a 3.3-fold improvement. This significant enhancement is mainly attributed to a 3.3% reduction in biodiesel production cost per liter and an 8.3% increase in annual biodiesel output.