ABSTRACT
When considering the options for intensifying reactions that involve multiple fluids, it is helpful to identify the shortcomings of the conventional equipment that is currently in use. In this context, perhaps the most frequently used item is the stirred vessel fitted with a cooling jacket, shown in Figure 1. A turbine impeller generates a circulation comprising two toroidal vortices, and the turbine torque is normally prevented from driving a free vortex by the use of wall baffles, as shown. If a gas-liquid reaction is involved, then the gas is usually injected directly below the impeller via a suitable sparging arrangement. The popularity of the stirred vessel is due to its perceived simplicity and adaptability, coupled with the fact that it is superficially straightforward to scale-up from the laboratory beaker that was used when the process was being developed. Unfortunately, it suffers from several serious problems, as indicated later.
