Simulation and Optimization of Hydrogen Production using the Coal Gasification Process

In this study, hydrogen production was simulated and optimized using the coal gasification in the moving-bed reactor. In this reactor, coal from the top and the combination of oxidizing gas and steam from below is in contact with solid and gas produced comes out from the top of reactor. The results of the simulation have been compared with the experimental values and the average relative error of 2.47% indicated acceptable accuracy of simulation results. The effects of inlet gas temperature, reactor pressure, ratio of steam to oxygen and coal to oxygen are investigated on the hydrogen production efficiency. Although some studies have been published regarding the modeling of the moving-bed reactor in the coal gasification, limited parametric studies are available to investigate the effect of different variables on the reactor performance with Pittsburgh coal as food. Also, in this study, simulation with discrete temperature for gas and solid to determine the exact maximum temperature of the solid phase, the kinetics of all possible reactions, simultaneous use of shrinking core and volumetric models in different areas of reactor and considering the distribution of gas components in the pyrolysis stage, happened that it is useful to find out more precisely the composition of the product gas. Finally, the reactor performance for generating maximum hydrogen yield is optimized using the particle swarm optimization method. The optimization results show that there is a 24.3% increase in hydrogen production yield compared to the basic mode.