In our role as a chemical process engineer, we need to follow up on raw material into products. How it takes will depend on a bunch of assumptions. In any case, to that come true, an industrial plant will have operating units, operation process or a mix of them.
A simple way to differentiate them is to consider that the operation unit refers to the physical processing of raw material. I mean, there is no chemical reaction to turn raw material into products. On the other hand, in the operation process, chemical reactions take place.
A good start to go deeper in this subject is to take a look at “The principles of Chemical Engineering” (William H.Walker, Warren K. Lewis and William H. McAdams). The authors first explained that the variety of chemical industries have processes which follow the same physical laws. They summed-up these similar processes into unit operations. For instance: heat transfer, fluid flow, distillation, absorption, drying etc.
Thinking about the operation process we have combustion and polymerization just to name some of them. This is a huge subject for sure.
