Kinetic based simulation of fixed bed gasifier and performance study on syngas production from different biomass feed-stocks

Abstract

Biomass is one of the most clean and renewable energy resources. In recent times, researchers have given more attention to biomass due to its zero emission of greenhouse gases such as carbon monoxide. In biomass utilization technologies, biomass gasification is an attractive mechanism for utilization of waste biomass generated from different agro-industries. Despite the application of fixed bed flow gasification on a large scale, the reaction rate in the hot conversion zone is almost unknown. However, knowledge regarding the rates of the gasification reaction at high temperature and high pressure is crucial for detailed design and optimization of these gasifiers. The study focused on the simulation of biomass (coffee bean and rice) husk gasification process based on the kinetics of the gasifier in order to investigate the produced syngas composition. The AspenPlus simulation was used to investigate the effect of operating parameters on the composition of the produced gas. Effect of different proportions of the simulation parameter includes gasification temperature, pressure, reactor volume, equivalence ratio and moisture on gas production and composition. Results of sensitivity analysis showed that an increase in temperature led to a rise in the production of H₂ and CO gases. Whereas, an increase in moisture content of the biomass showed lower heating value of the produced gas. Based on the obtained result, the maximum lower heating value of syngas was obtained at the gasification temperature of 800^oC, steam to biomass ratio of 0.1, pressure of 1 bar, 0.05% of moisture content and 0.02 m³ of reactor volume.