A modelling based study on the integration of indirect biomass gasification, methanol and power production

This work focused on system modelling regarding the investigation of biomass gasification and its integration with methanol synthesis and power production. Indirect gasification technology was chosen and modelledusing Aspen Plus®. The gasification process along with the reaction kinetics were validated with experimental data from the literature. Different processing steps towards the conversion of biomass to methanol were identified and modelled. The identified process blocks were: Gasifier, Gas Cleaning Unit, Methanol Synthesis and the Energy Conversion Network were optimised by performing a series of sensitivity studies. The optimised model was then used to study the effect of choosing different technologies and parameters within the blocks on the overall process behaviour. Two different case studies were examined, each distinct from each other by a difference in technology of one of the blocks. The two cases concerned the impact of incorporation of Absorption Enhanced Reforming (AER) on the methanol synthesis process, simulated by using dolomite as the bed material. Sankey plots for each of these cases were drawn to visualize the energy losses in such complicated systems. The developed model accurately predicted the composition of the major product gas and operational conditions of all the identified blocks within the methanol synthesis process. The effect of incorporating AER on the overall methanol synthesis process was simulated. The developed model proved its use as a generic tool to compare the effect of different choices in technology on the performance of the overall process.