Packed bed methanol reactor with flow diverters

Abstract

This study proposes a novel forward mixed multistage packed bed reactor (FMMPBR) for methanol synthesis. The reactor and reactants are divided into multiple stages with the provision of flow diverters to optimise the concentration of reactants and amount of catalyst along the length of the reactor. A steady state 1-D reactor model of the FMMPBR for methanol synthesis was developed and validated against previously published experimental data. Multi-objective optimisation was carried out to optimise inlet flowrate, space velocity and the concentration of reactants in each stage of the reactor. Simulations were carried out with an objective to achieve either maximum carbon conversion or minimum temperature deviation (isothermicity). The performance of FMMPBR was compared with that of the standard tubular reactor. When optimised for maximum carbon conversion, the FMMPBR resulted in ∼5% higher carbon conversion, ∼15% lower catalyst requirement and lower operating flowrate compared to the standard single tube reactor; and when optimised for minimum temperature deviation along the reactor length, the FMMPBR resulted in slightly lower carbon conversion, ∼34% lower catalyst requirement, reduced temperature standard deviation by 25%, and higher production rate.