An influence of the inert gas on the operation and design of a multi-tubular reactor

The heat transfer effect of carbon dioxide inert gas on a multi-tubular reactor was investigated on three partial oxidation systems such as the partial oxidation of butane to maleic anhydride, o-xylene to phthalic anhydride and propylene to acrolein using a numerical simulation. The heat removal capacity of carbon dioxide inert gas was larger than that of nitrogen resulting in higher conversions when operating the multi-tubular reactor. While the multi-tubular reactor is designed for o-xylene partial oxidation using a carbon dioxide inert gas, the diameter of the reaction tube can be increased up to 1.8 times comparing with that of the reaction tube using a nitrogen inert gas due to efficient heat transfer, which shows 3.2 times productivity gains. The phase diagrams of inlet and coolant temperatures also show that the workable or safe ranges of reactant inlet and coolant temperatures are larger with a carbon dioxide gas.