Scaling Up Stirred Tanks with Boiling

We distinguish three situations where boiling occurs in a stirred tank  

The bulk fluid at its boiling point but agitation is good and few bubbles form on the metal surfaces. Instead, homogeneous nucleation occurs near the surface of the liquid where the temperature exceeds the boiling point. The liquid head suppresses boiling deep within the vessel, and the bubble volume is typically a few percent of the liquid volume. This form of heat transfer also scales as 

In some chemical systems, boiling can create relatively stable foams. Foams can also result from the release of a gaseous byproduct. Such problems are usually apparent on the small scale. Anti-foaming agents are sometimes effective. 

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