Chemical Engineering Science

Abstract

This chapter considers chemistry to be the science of the transformation of substances, including transformations that do not involve chemical reactions (such as distillation or grinding). Chemical engineering science is the discipline concerned with the mechanical, physical, physicochemical, and chemical aspects of all (industrial) processes in which substances are transformed. Processes in chemical plants are not only dependent on chemical events, but also (and often predominantly) determined by “transport phenomena” (momentum, heat, and mass transfer). Knowledge of combined mass, heat, and momentum transfer is crucial to chemical engineering. For a chemical reaction to proceed, there has to be energy and mass transfer, usually supported by forced flow of gases and liquids (momentum transfer). Further, there is virtually no production of chemicals without some pre-processing of raw materials and, crucially, “downstream processing” to separate and purify reaction products. In general, the cost of operations before and after a (bio)chemical reactor is greater than the expenditure of the reactor itself. This chapter assumes that the focus or “essence” of chemical engineering has been the same over the past century, viz. “unit operations and transport phenomena.”