The simplest type of reactor is a batch reactor. Materials are charged in a batch reactor, and the reaction proceeds with time. A batch reactor does not reach a steady state, and control of temperature, pressure and volume is necessary. Thus, a
batch reactor has ports for sensors and material input and output. Batch reactors are used in small-scale production and reactions with biological materials, such as in brewing, pulping and production of enzymes.
===CSTR (Continuous Stirred-Tank Reactor)===