Process Intensification and Miniaturization in Gasification Technology: Downdraft Gasification of Sugarcane Bagasse

Abstract

On a global scale, the quantity of biomass waste is steadily increasing, particularly in densely populated urban areas. The electricity and heat energy generation from biomass gasification is a viable sustainable process and substitutes fossil fuels, which can decrease greenhouse gas emissions, in particular, reduce carbon dioxide gas. In this work, sugarcane bagasse as a biomass fuel was considered for combustible gas generation by utilizing an intensified downdraft-throated gasifier. The study showed that sugarcane bagasse has a calorific value of around 17.7 MJ/kg and can be densified in the form of briquettes, which is found to be an appropriate feedstock for gasification in a downdraft gasifier generating an average of 2.05 N m(3) of produced gas per kilogram of bagasse with a calorific value between 3.30 and 4.56 MJ/N m(3). Biomass feed rates for the gasifier varied between 2.87 and 7.44 kg/h were utilized in the experiments. The produced combustible gas mixtures were determined as CO, H-2, CH4, C2H2, C2H4, and C2H6, which constitute 25-27% v/v of the entire produced gas. The volume of produced synthetic gas (syngas) ranged from 2.05 to 2.16 N m(3)/kg of bagasse gasified. Above 99% transformation of solid carbon in the bagasse to product gas was accomplished by utilizing the intensive gasification system; however, it is required to apply a gas clean-up process to mitigate against any possible harmful impacts.