Simulation and optimization of CSTR reactor of a biodiesel plant by various plant sources using Aspen Plus

Abstract

AbstractIn the present paper, an integrated continuous process of biodiesel manufacturing is proposed using Aspen Plus simulator for different feedstocks. Majority of the reported simulation models in literature are design models for new processes by fixing some level of equipment performance such as the conversion in reactor. Most models assume the feed oil as pure triglycerides or some fatty acids and the biofuel as pure ester. In order to optimize the production of biodiesel, similarity with reality is necessary. For this purpose, this work uses thermophysical property estimation of glycerides, rigorous reaction kinetics, phase equilibrium for separation and purification units, and prediction of essential biodiesel fuel qualities. Detailed operating conditions, equipment designs, and properties of feed and products were obtained. The reactions and parameters kinetics were applied to represent both methanolic and ethanolic transesterification of the biodiesel production. An evaluation of optimal operating conditions (time, temperature, alcohol: oil ratio) for a CSTR reactor was determined. The optimal conversion was achieved at a temperature of 60 °C, 6.00 mol/mol alcohol-oil ratio and 2.0 h residence time when used methanol transesterification reaction as 88.19, 93.77, 89.43, and 89.25%, respectively for sunflower, soybean, palm and macauba oil, on the other hand 86.09, 80.26, 76.54, and 76.39% for transesterification ethanolic. Most of the biodiesel obtained from the simulations presented adequate according to the specifications of the D6751, ANP 45, and EN 14214 standards. Finally, the model proposed can be used for improving operations conditions, new products design and help economic analysis in continuous processes of biodiesel production.