Modelado y simulación de procesos involucrados en la producción de bioetanol a partir de suero de leche.

Abstract

Simple distillation is a purification process based on volatilities difference, and is mainly applied to binary or multicomponent mixtures whose boiling temperatures differ by at least 10°C. The distillation of alcoholic fermentation products has become a conventional process due to the low concentration of ethanol, which can be envisaged as non-ideal system as it presents an azeotrope at the 88% mole fraction. In this context, the liquid-vapor equilibrium analysis requires the incorporation of activity coefficients. The thermodynamic models NRTL and UNIQUAC are the likely alternative to describe the real behavior of these kind of mixtures. This project aims to simulate the simple distillation of whey fermentation product to achieve an 88 % mol ethanol by means of NRTL and UNIQUAC models. For this purpose, the number of theoretical plates and the feeding plate were determined through McCabe Thiele graphical method. A distillation simulation was carried out in Aspen HYSYS V12.1 process software. It was found that NRTL model is the most suitable for the fermented whey since product purity and recovery percentage are like those experimentally attained. In addition, the reflux ratio influence levels were established, since it was demonstrated that an increase in reflux promotes higher purity product and higher percentage of recovery.