Operation of coaxially cooled fixed-bed catalytic reactors: conditions of existence of the pseudoadiabatic regime

Abstract

The Pseudoadiabatic Operation (PO) of multitubular fixed-bed catalytic reactors allows to control the hot-spots for highly exothermic reaction systems, locating them at the outlet of the unit. This regime can be applied succesfully to the methanol-to-gasoline conversion process (MTG). A theoretical demonstration is presented, for first-order or pseudo-first-order reactions, proving that the fully countercurrent mode does not admit PO regimes. The study is completed with the development of an “ a priori” criterion for the prediction of operating conditions admitting the PO when the inlet coolant temperature is different from that of the reactant stream.