A Continuous Stirred Tank Reactor (CSTR) is a reaction vessel in which reagents, reactants and often solvents flow into the reactor while the product/s of the reaction concurrently exit/s the vessel. In this manner, the tank reactor is considered to be a valuable tool for continuous chemical processing.
Continuous Stirred Tank Reactors (CSTR) have effective mixing and perform under steady-state with uniform properties. Ideally, the output composition is identical to composition of the material inside the reactor, which is a function of residence time and reaction rate.
In situations where a reaction is too slow or when two immiscible or viscous liquids are present requiring a high agitation rate, several Continuous Stirred Tank Reactors (CSTR) may be connected together into a cascade. A Continuous Stirred Tank Reactor (CSTR) assumes ideal mixing, and thus, is the complete opposite of a Plug Flow Reactor (PFR).