Sugarcane Bagasse Gasification: Thermodynamic Modelling and Analysis of Operating Effects in a Steam-Oxygen-Blown Fluidized Bed using Aspen PlusTM

Sugarcane bagasse is an abundant agricultural residue derived from the sugar-alcohol industry, which is usually burned in boilers for power generation. However, this practice results in relatively low yields and ash production, requiring the investigation of novel methods of sugarcane bagasse conversion. In this context, gasification arises as a promising option: it is a thermochemical process that converts a wide range of carbonaceous resources into syngas, a gaseous mixture that mainly contains H2, CO, CO2, CH4 and light hydrocarbons, and can be applied in the generation of heat, power, and chemicals. Gasification can be held in different gasifier configurations, but special attention is given to fluidized beds due to advantages such as feeding flexibility and scalability, high heat and mass transfer rates, and high reaction rates. Despite the given panorama, there is a lack of data in the literature of sugarcane bagasse gasification in bubbling fluidized beds operating with steam and oxygen as gasifying agents. To address this subject, this work performed a simulation of sugarcane bagasse gasification in a steam-oxygen-blown bubbling fluidized bed based on Gibbsfree energy minimization using Aspen PlusTM. With the proposed model, a 24 factorial design was conductedwith the intent to study the influence of gasification temperature, pressure, biomass moisture content, and steam-to-biomass ratio (S/B) on syngas production. The obtained results have shown how different operating conditions and their interactions affect gasification exothermic and endothermic reactions and, consequently, compositions and performance indicators. Finally, the present work has demonstrated that sugarcane bagasse gasification is a potential and feasible process for clean energy production, contributing as an alternative for this agricultural waste use.