Simulation of pyrolysis and gasification of sub bituminous coal using aspen plus: article

The purpose of this study is to simulate the decomposition process of the coal by pyrolysis process and to simulate the gasification process of the pyrolysed product. Simulation of this process was done in order to transform the coal into synthesis gas. This was done by using pyrolysis and gasification process. Gasification is a process where thermochemical reactions takes place. The coal was transformed by partial oxidation into synthetic gases. In the simulation by using Aspen Plus, the main syngas formed is carbon monoxide, hydrogen and carbon dioxide. These gas are used in electricity generation as a fuel to the turbines. In this project, the rigorous model that was used to simulate the pyrolysis and gasification process is R-Yield and R-Gibbs respectively. R-Gibbs model are used to determine the equilibrium composition of the expected products which involves various kinds of chemical reactions. R-Yield model was used to simulate the decomposition yield of the coal based from the ultimate analysis and proximate analysis obtained from references. The R-Yield model was simulated with the help of FORTRAN code which is needed to calculate the amount of yield. The syngas yield from the gasifier are 85.47% mass. A solid-gas separator was used to simulate the separation of the ashes obtained from the pyrolysis process. The main concern of the process is the cleaning of the gas. The results obtained shows that the cyclone which was used for the solid-gas separation was successfully separated with an efficiency as high as 95%.