NOVEL AND SIMPLE JET-STIRRED REACTOR FOR HOMOGENEOUS AND HETEROGENEOUS REACTIONS WITH SHORT RESIDENCE TIMES

A novel and simple cylindrical jet-stirred reactor with short residence times (about one second) is described. Stirring is achieved by means of four turbulent jets issuing from nozzles. Perfect macromixing has been checked for space times between 0.5 and 4 s in the empty reactor and from 0.5 to 1.5 s in the reactor packed with glass rods. Heat transfer at the wall of both the empty and packed reactors has been studied in the perfect mixing range. For instance, the following correlation was obtained for the empty reactor:. Nu = 12 + 0.0460 ReNozzle Pr-1.5. This device was found to be a much better heat exchanger than an empty tube reactor with the same diameter and at the same flowrate. Finally, ten individually jet-stirred cells have been connected in series, allowing plug flow to be approached. Thanks to the high heat transfer rate at the wall, it was shown by computer simulations that the well-known hot spot" problem could be avoided in the jet-stirred cascade if exothermic reactions were carried out in both empty and packed jet-stirred reactors. © 1979."