Aspen Plus Simulation of Biomass Gasification with Known Reaction Kinetic

Abstract

The energy from biomass can be utilized through the thermochemical conversion processes of pyrolysis and gasification. The Aspen Plus simulation tool is applicable for simulation of the gasification processes. The most common way is to simulate the gasification reactor using Gibbs reactor, which applies Gibbs free energy minimization to calculate equilibrium. The reactions in the gasification process are complex and by using the Gibbs reactor, it is not necessary to specify the stoichiometry or the reaction rates. However, reactions that describe the major conversion rates in a gasifier can be extracted from the literature. By using these reaction rates in Aspen Plus, it is possible to simulate the gasification process also by using a continuous stirred tank reactor (CSTR). Comparison of the composition of produced gas based on simulation with Gibbs reactor and CSTR is performed. The influence of parameters like reactor temperature, residence time and steam flow rate are studied.