Comparison of sugarcane bagasse conversion to syngas in downdraft and fluidized bed gasifier using ASPEN PLUS

Abstract

Sugarcane bagasse is generated in large quantities during the processing of sugarcane in the sugarcane industry. For a country like Indonesia with its vast agricultural residues such as sugarcane bagasse, it is imperative to have an efficient power generation system utilizing the residues. Gasification of sugarcane bagasse is a carbon dioxide emission neutral source of energy and also has the advantage of syngas production. Syngas composition varies based on gasification technology used and can be adapted to specific applications. Among the gasification technologies that are widely used are downdraft and fludized beds. The objective of this work, therefore, is to provide a comparison between downdraft and fluidized bed gasification based on the production capacity of syngas using Aspen Plus simulation. The sugarcane bagasse used in the simulation was obtained from sugar factory PG Gempolkrep Mojokerto, East Java. The results show that at the ratio of steam to biomass equal 1.0, H2 decreases with increasing temperature both with downdraft and fluidized bed gasification. CO increases with increasing temperature in the downdraft gasification, but decreases with increasing temperature in fluidized bed gasification. At temperature 750°C, H2 increases with increasing the ratio of steam to biomass, but decreases with increasing the ratio of steam to biomass. Meanwhile, CO decreases with increasing the ratio of steam to biomass for both downdraft and fluidized bed gasification. From the aspect of CO2 produced, it can be concluded that fluidized bed gasification is more environmentally friendly than downdraft gasification.