New scale-up and design method for stirrer agitated batch mixing vessels

Abstract Residence time distribution theory and probability conditions predict that the infusion rate of a slug of tracer into a batch mixer can be characterized by a single quantity, a decay rate constant. This constant is then used to define a dimensionless mixing-rate number. Experiments in turbine-agitated and propeller-agitated fully-baffled tanks verify the theory, and relate this mixing-rate number to the stirrer Reynolds number and to the Power number for mixing. These new correlationships allow calculation of time needed or energy input needed to achieve any desired degree of uniformity of the mixture.