(93a) Recipes, Models, Chemical Processing and CRE

The essence of chemical engineering is to come up with recipes and models to help us efficiently make the materials wanted by man. In the first half of the 20th century studies focused on the chemical reaction step, and the book by Hougen and Watson was the guiding text for this approach. We call this the American approach. In the 1950's European engineers broadened their scope to consider not just the chemical step but also the heat, mass, diffusion and flow pattern steps which affect the overall rate. These are all critical for getting a reasonable processing model. We call this the European approach. The European approach is more teachable and in general is simpler and more direct, and thus has been widely adopted by engineers working in all sorts of areas. In the coming century the dominant emphasis in chemical engineering will shift from the processing of petroleum to some other feed material, maybe coal. This paper sketches this story.