EFFICIENCY IMPROVERMENT OF BAGASSE UTILIZATION IN SUGAR MILLS

Abstract

Biomass energy is useful in mitigating greenhouse gases as biomass growth captures CO2 from the atmosphere. This captured CO2 is eventually released upon the use of these biomass feed stocks, leading to a short duration carbon cycle. One prominent biomass feedstock is the sugarcane bagasse that is a by-product of sugarcane mills. Conventionally, the bagasse produced after crushing sugarcane is utilized in mills by directly burning it in the boilers. However, an efficient way of utilizing this biomass fuel would be through gasification. The biomass gasification process yields syngas which is used as fuel for meeting the heat and power demands of the sugar mill, as well as excess electricity, which can be supplied to the grid. Additionally, this syngas produced can be for manufacturing methanol and other high-value chemicals. The present study aims to highlight the efficiency improvement potential of bagasse gasification. The entire sugar mill as well as the bagasse gasification process, have been modelled in the ASPEN Plus software. Heat integration has been performed to optimize the process flowsheets. The electrical energy generated by combusting bagasse is estimated to be 0.1-0.2 kWh/kg of bagasse combusted. In contrast, the gasification process can increase this energy generation up to 0.5 kWh/kg of bagasse at 12% moisture content. This study aims to provide awareness about the cleaner and efficient utilization of the energy that lies dormant in these industrial residues.