Desenvolvimento de um reator de leito fluidizado aplicado à combustão de gás natural

Abstract

The burning of natural gas in conventional boilers typically generates high indices of NOX emission, which has aroused the interest of researchers for new forms of combustion. In this context, Combustion in Porous Media has emerged as a promising alternative, compared to the experimental results regarding the NOX emissions, obtained in a laboratory environment. As a developmental process of this technology, in terms of practical application, Fluidized Bed Combustion (FBC) is presented as advantageous due to the fact of the porous medium to move itself by action of gases under pellets resulting in lift force. This technology leads to its application to system projects dedicated to renewable energies, such as biomass. Then, this work has the purpose of investigating parameters of the porous bed fluidization and of FBC, applying them to the development of a fluidized bed reactor (FBR) in laboratory scale, since the use of natural gas as fuel. In this direction, the fluid-dynamic behavior of the bed was studied, which is constituted of silica particles, initially through a research setup in order for a later study on actual operating conditions. FBR was developed based on the preparation of the basic and constructive designs, utilizing the fundamentals of technology and laboratory investigations. The present phenomena in the process were experimentally analyzed, based on classical equations that characterize the fluiddynamic behavior of the bed, considering the influence factors such as: roughness of the inner surface of the reactor; operation temperature, flow regime, among others. The experimental work highlighted the importance of controlling FBR, concerning the fuel-air mixture ignition in the fluidized bed, pointing out the influence of temperature on the fluidization, which justified the use of engineering strategies to deal with the ignition process.