A generalized mixing model for initial contacting of reactive fluids

Abstract This paper deals with the representation of phenomena occurring when a fluid stream containing reactive species comes into contact, mixes up and reacts with an excess of miscible fluid. The various steps of the mixing process are: erosion of fresh fluid, dilution of the smaller eddies into the reacting zone, invasion of this zone by incorporation of bulk fluid, and exchange or diffusion between small eroded and incorporated eddies in the reacting cloud. Material balance equations are derived both in a Lagrangian and in an Eulerian framework. It is shown that the Generalized Mixing Model (GMM) contains previously published models as special cases. Two samples of application are presented and discussed: mixing in semi-batch reactors of different sizes studied by a novel parallel-competing test reaction, and mixing of a stream of initiator in a recycle tubular reactor packed with static mixers for the polymerization of styrene.

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