Concepts for Scale-up in a Loop Reactor

Authors: 
Shinkle, A. A., The Dow Chemical Company

Batch chemical operations are regularly used for fine and specialty chemicals due to versatility of the reactor for use on the next product.  However, continuous processes have begun to gain traction.  One particular kind of continuous reactor is the loop reactor which is a vessel-less CSTR involving a loop of piping which the process fluid is recirculated around at a much faster rate than product is withdrawn.  Loop reactors are commonly considered when one of the following conditions are met: hazardous chemicals are used, significant heat removal is needed, reaction rate is fast, significant decomposition reactions occur, or high local mixing is required.  This poster discusses several design concepts and key challenges that may be useful when setting up lab-scale loop reactor systems.  Specific focus is placed on the role of multiple phases in the loop reactor.  Examples of lab-scale loop reactors built at Dow Chemical are given along with statistics showing how the loop reactor process compares with the equivalent batch process.