What Is the Difference Between Batch and CSTR Reactors? A Detailed Comparison When designing or selecting industrial reaction systems, process engineers frequently choose between two foundational reactor configurations: Batch Reactors and Continuous Stirred-Tank Reactors (CSTR) . The fundamental difference lies in their operational mode and flow dynamics: a batch reactor operates discontinuously in an unsteady state where materials are processed in closed cycles, while a CSTR