Exergetic Analysis between a First-Generation Bioethanol Production Plant and a Second-Generation Plant Coupled to Conventional Process

Abstract

Large consumption of non-renewable fuels in the world has strongly encouraged the search for biofuels, due to inevitable shortage of fossil energy sources and catastrophic problems generated by their use. Under these circumstances the so called second generation biofuel production has been highlighted, where lignocellulosic materials such as sugarcane bagasse are used to produce bioethanol, unlike the traditional first-generation process, whose feedstock is sugarcane. Therefore, this work aimed to perform a comparative exergetic analysis between first and second-generation bioethanol production processes, in order to evaluate from the exergetic point of view, which of these processes is the most feasible. It was found an overall exergetic efficiency of 60.89 % for the exclusively first-generation plant, whereas for the integrated plant, it was obtained 41.58 %. In this way, insertion of new stages in production process, required by the second generation, has caused consequently an increase of irreversibilities and losses.