Methanol

Abstract

A single pressure process for the production of methanol wherein the make-gas is produced by steam reforming a hydrocarbon feedstock, in admixture with recycled purge gas from the synthesis loop, at such a pressure that the make-gas can be fed without further compression, to the synthesis loop at a pressure no lower than the pressure at the inlet to said circulator. The reforming is effected by primary steam reforming followed by partial oxidation with oxygen and secondary reforming, without any bypass of the feedstock of the primary reforming stage, so as to give a make-gas of approximately stoichiometric composition for methanol synthesis. The primary reforming is effected at above 55 bar abs. over a catalyst disposed in tubes heated by passing the secondary reformed gas stream past the external surfaces of the reformer tubes in a direction counter-current to the flow of reactants undergoing primary reforming in said reformer tubes. In this way heat is transferred from said secondary reformed gas stream through the walls of said tubes to supply the endothermic heat of the steam reforming reaction. In preferred forms of the process the steam is incorporated into the feed to the reformer by saturation and the excess of steam is removed from the reformed gas by direct contact with cold water: in this way a high pressure steam system recovering power from the reformed gas is not needed.