Unit Operations of Chemical Engineering

Chemical engineering has to do with industrial processes in which raw materials are changed or separated into useful products. The chemical engineer must develop, design, and engineer both the complete process and the equipment used; choose the proper raw materials; operate the plants efficiently, safely, and economically; and see to it that products meet the requirements set by the customers. Chemical engineering is both an art and a science. Whenever science helps the engineer to solve a problem, science should be used. When, as is usually the case, science does not give a complete answer, it is necessary to use experience and judgment. The professional stature of an engineer depends on skill in utilizing all sources of information to reach practical solutions to processing problems. The variety of processes and industries that call for the services of chemical engineers is enormous. Products of concern to chemical engineers range from commodity chemicals like sulfuric acid and chlorine to high-technology items like polymeric lithographic supports for the electronics industry, high-strength composite materials, and genetically modified biochemical agents. The processes described in standard treatises on chemical technology and the process industries give a good idea of the field of chemical engineering, as does the 1988 report on the profession by the National Research Council! Because of the variety and complexity of modern processes, it is not practicable to cover the entire subject matter of chemical engineering under a single head. The field is divided into convenient, but arbitrary, sectors. This text covers that portion of chemical engineering known as the unit operations.