A SHELL-AND-TUBE PYROLYSIS REACTOR FOR OLEFIN PRODUCTION

A new thermal cracking technology using shell-and-tube type pyrolysis reactors, in which the accent is shifted from radiative to convective heat transfer, is introduced. A smooth temperature distribution can be achieved with the proposed reactor geometry. This lowers the coking rate and increases the run length of the reactor and the lifetime of the tubes. A reactor model accounting in great detail for the reactor geometry and the different heat-transfer mechanisms is combined with a rigorous kinetic model based on radical reaction mechanisms to predict the temperature distribution in the reactor, the heat transfer from flue gas to process gas, and the naphtha conversion, together with the associated product yields for the various tubes.