Speeding the design of bioseparations: A heuristic approach to engineeringdesign

A variety of economic and social pressures require lowering the costs of eq uipment and process development, and particular emphasis must be placed on speeding what is basically a heuristic activity. The early stages of concep tualization and screening of alternatives are the most critical, and it is precisely these which have largely been ignored in the public literature an d academic curricula. Such early decisions must be made without detailed un derstanding, and they are essentially evolutionary activities (Lightfoot, E . N. Chem. Eng. Frog. 1998, Jan, 67-74). Evolution dynamics are notoriously unpredictable, and yet observation of biological evolution shows that they can be both surprisingly fast and efficient. Here methods are suggested fo r achieving high efficiency for equipment-and process development. A critic al feature of evolutionary dynamics is the need to identify system anomalie s, and these can only be discussed effectively through use of specific exam ples. Here examples will be taken from the general area of separations proc esses, with particular emphasis on biological separations.