Simulation of a three phase reactor for the solvent methanol process

Single pass conversions in conventional vapor phase methanol synthesis are low, necessitating recycle of large quantities of unconverted reactants. In the Solvent Methanol Process (SMP), the use of an inert and highly selective solvent in the synthesis loop enables the removal of methanol as soon as it is formed and helps overcome equilibrium limitations that exist in the vapor phase process. An industrial scale, packed bed, adiabatic reactor with cocurrent upflow of synthesis gas and solvent has been simulated for the SMP. The simulation shows that very high single pass conversions of CO and Hzare attainable such that recycle can be eliminated. Reaction rates are however lower than vapor phase rates due to pore diffusion limitations.