Tese de Doutorado
Predição de propriedades, modelagem e simulação de processos de conversão de óleos vegetais em biocombustíveis por rota convencional e desoxigenação
Fecha
2016-01-29Autor
Gisele Cristina Rabelo Silva
Institución
Resumen
Researches focusing on the development of biofuel production processes have increased significantly in recent years, mainly for environmental and economic issues.The identification of low-cost raw materials, including mixtures of different sources, either raw or recycled raw materials, and the development of simulation models able to predictthe conditions of production and the properties of the components may be the way to obtaining economically viable biofuels. Simulators models are commonly used to provide reliable information on chemical processes due to their libraries of components, thermodynamic packages and advanced computational methods. They are an importantoptimization tool of predicting the final products properties based on the raw material characteristics, reducing time, wastes and cost. To carry out the simulation of a biofuel production process and the determination of properties of the final product using a process simulator, it is necessary to know the start condition and parameters of the oil and the processing steps to obtain biofuel, including the flow chart of the process, the kineticparameters and thermodynamic models. The initial objective of this study was to evaluate methods for predicting physical and thermodynamic properties in order to develop a database of the compounds involved in the biofuels production's process and to recommend appropriate methods based on accuracy and consistency of data obtained. Asimulation model of the biodiesel production process through methanol and ethanol transesterification's reaction was created, in which vegetable oils were characterized based on the estimated properties. The plant performance was analyzed by including the kinetics of the reactions and phase equilibrium. Finally, a new technology of third generation biofuels was proposed, green diesel named deoxygenation. It was analyzedthe simulation design of one renewable diesel production plant developed, addressing the most important issues related to this new technology. Further, the most influential parameters of the reactions was evaluated and optimized. As a result of this presented work, it was obtained the mass and energy balances involved in plants proposed, the flow chart of the process by simulation and the comparison of biofuels properties obtained after the simulation run. The project showed similar conversions to those found in experimental studies, indicating that the model can be used to study the deoxygenation process for the production of biofuels, whose properties are within the limits established by regulatory agencies. The conversion of the vegetable oils in biofuels by deoxygenation is an interesting alternative to the traditional process, transesterification, since as thisrenewable diesel has better properties than the petroleum diesel and biodiesel, as the cetane number, viscosity and density. In addition, by this process one may use low cost raw materials, as well as the existing infrastructure in petroleum refineries.