Reactive simulation of gas-catalyst thermochemical properties in a pilot-plant catalytic MTO fluidized bed

Abstract

The methanol-to-olefin (MTO) process enables economical production of light olefins thus decreases the reliance on petroleum resources. The reactive multiphase flow patterns and reaction behaviors inside pilot-plant MTO fluidized reactor are numerically simulated with multiphase particle-in-cell model. Based on the model validation, the thermochemical properties of catalytic particle (e.g., heat transfer coefficient (HTC), temperature) and gas phase thermal characteristics are comprehensively investigated with the discussion on several crucial operating parameters. The results reveal that large HTC of catalyst particle is located in the crucial reaction zone and freeboard zone. The HTC of catalyst material covers a range of 50 to 150 W/(m2·K). Gas-solid hydrodynamics and gas concentrations exhibit spatial non-uniform distribution. Moreover, the reactant gas flow rate is more positively sensitive to the product distributions and gas thermal properties. Enlarging the reaction pressure significantly enhances the heat transfer. The vertical dispersion coefficient of catalyst is two orders of magnitude larger than the horizontal ones.