Detailed design of unit operations is usually done in practice by third-party vendors. Process plant designers should not spend more time than is warranted by our responsibility to make sure that the design envelope given to vendors is robust in designing unit operations. Rule of thumb design is the norm for process plant designers, though simulation programs may have a limited applicability if used appropriately.
Unit operation design; rule of thumb
Process plant designers very rarely carry out detailed design of unit operations, as they do not intend to offer the process guarantees for the units. Detailed design is a job for those guaranteeing the performance of the unit operation.