Simulation of batch physical refining and deodorization processes

This work presents an application of a differential distillation model for the simulation of batch physical refining and/or deodorization processes in the vegetable oil industry. The vapor-liquid equilibria of these fat systems are described by group contribution equations for vapor pressures and activity coefficients published elsewhere (Ceriani, R., and A.J.A. Meirelles, Predicting Vapor-Liquid Equilibria of Fatty Systems, Fluid Phase Equilib. 215:227-236, 2004; Fredenslund, A., J. Gmehling, and P. Rasmussen, Vapor-Liquid Equilibria Using UNIFAC, Elsevier Scientific, Amsterdam, 1977). The full complexity of the oil, expressed as its total composition of TAG, DAG, MAG, and FFA, is considered within the simulation. This approach permitted us to quantify and qualify distillative neutral oil losses during physical refining. Three different models of differential distillation were tested to develop a good representation of the batch process to be applied to the physical refining and/or deodorization of complex mixtures such as vegetable oils. To evaluate the recommended approach, a case study was performed, namely, a batch deodorizer was simulated for coconut oil refining, and the results were compared with those reported in the literature.