This work investigates computationally the modeling of sugarcane bagasse pyrolysis in a bubbling fluidized bed reactor. An Euler−Euler multiphase approach, as invoked by the open code MFIX (Multiphase Flow with Interphase eXchanges), is adopted, and the simulations are carried out in a two-dimensional Cartesian domain. While several pyrolysis kinetic models have been developed for wood, coal, and generic biomass, generally using thermogravimetric analysis, no such model has been specifically tested or adapted to simulate sugarcane bagasse pyrolysis in fluidized bed reactors through computational fluid dynamics. In the present study, seven pyrolysis kinetic models available in the literature are implemented as MFIX user-supplied routines and evaluated within given operational temperature ranges. Initially, well-established wood pyrolysis results are used to validate the implementations. Following validation, six kinetic schemes are employed to simulate sugarcane bagasse pyrolysis. Results for the products distribution, formation reaction rate profiles, and tar composition at different operating temperatures of the fluidized bed reactor are obtained for all models and compared to published experimental results. Based on the assessed predictive performances of the models, indications are drawn for the most appropriate models to simulate the reactor under different operating conditions.

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Gasification of pelletized sugar cane bagasse, the waste residue from sugar cane, was carried out using an atmospheric pressure 100 kW th steam-oxygen blown circulating fluidized bed gasifier (CFBG). The purification of the syngas produced was carried out using a high temperature filter unit which contains 3 rigid ceramic candles with an outer diameter of 60 mm and a length of 1500 mm.Keeping the gasification temperature in the range of 800°-860°C and using magnesite M85 as the bed material, the effects of operational conditions (e.g. steam to biomass ratio (SBR) and oxygen to biomass stoichiometric ratio (ER)) and of catalytic and non-catalytic filtration on the composition distribution of the product gas and tar formation were investigated. Higher temperature and SBR values were favorable for increasing the mole ratio H 2 to CO and decreasing the tar compound (PAH) concentration on dry basis, measured via solid phase adsorption (SPA) sampling and subsequent GC analysis varying from approximately 2 to 6 g/m n 3 . At the same operational conditions, in the downstream filter, the conversion of tar content obtained using catalytic filter candles increased by a factor of 2.8 compared to the one with non-catalytic filter elements. The specification and distribution of major ash forming elements were investigated by SEM-EDS. Experimental results showed that bagasse is an interesting fuel for syngas production via the gasification process, both from a gas composition and from a tar production point of view.

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