Thermodynamic model for process design, simulation and optimization in biodiesel production

N. COTABARREN; S. B. BOTTINI; S. PEREDA; E.A. BRIGNOLE

Conferencia; IX Iberoamerican Conference on Phase Equilibria and Fluid Properties for Process Design (EQUIFASE 2012); 2012

The biodiesel production industry requires thermodynamic models able to correlate and predict the phase equilibria of the mixtures present along the process. Moreover, data of high accuracy are required due to their sensitivity to the components distributions.A typical example is the removal of glycerol in the biodiesel washing unit. In this work, the Group Contribution Equation of State (GCA-EoS) is applied to model several systems of importance in this field. The mixtures evaluated can be highly non-ideal, for example in the last purification steps where polar compounds are infinitely diluted in biodiesel. Experimental VLE and LLE data were satisfactorily correlated and predicted with a single set of interaction parameters, using a simplified version of the associating contribution of the model. In this way GCA-EoS can be used for the whole process with a faster convergence of simulated units in comparison with the case of considering the rigorous association model. Furthermore, considering that GCA-EoS is a group contribution model, biodiesel production from different raw material, i.e soy, palm or canola oil, can be predicted without requiring new parameters adjustment.