UNIVERSIDADE FEDERAL DE ITAJUBÁ NÚCLEO DE EXCELÊNCIA EM GERAÇÃO TERMELÉTRICA E DISTRIBUÍDA PROGRAMA DE PÓS-GRADUAÇÃO EM ENGENHARIA DE ENERGIA
Biomass; gasification; bubbling fluidized bed gasifier.
This study presents a methodology for the design of a bubbling fluidized bed gasifier and its application in the design of an equipment built and installed at the Federal University of Itajubá, using as biomass the bagasse of sugarcane and directed to the production of biofuel via the Fisher-Tropsch process. The methodology is divided into two parts: the Thermodynamic Analysis and the Hydrodynamic Analysis. For Thermodynamic Analysis, the Thermodynamic Equilibrium Model that is responsible for the predictability of the gasification process was used. In the Hydrodynamic Analysis, the fluidization conditions are analyzed. By combining these analyses, it is possible to obtain the proper geometry of the reactor. The first geometric parameter to be obtained is the diameter of the bed. In order to determine the height of the reactor, this element is divided into two regions for analysis: the bed region and the freeboard region. In the described application, the following was foreseen for the operation: mass flow rate of sugarcane bagasse of 10 kg/h (dry basis), ER of 0.3 and S/B of 0.6. With this, a gasifier of 0.32 m in diameter and 0,36 m in height with respect to the bed region was obtained; for the freeboard region, a conical region was introduced that resulted in 0.27 m height and an opening angle of 5 °, and for the cylindrical region 0.36 m in diameter and 1,54 m in height - which resulted in a total height of 2.17 m.