PROCESS SYNTHESIS FOR WASTE MINIMIZATION

The hierarchical decision procedure described by Douglas provides a simple way of identifying potential pollution problems early in the development stages of a design. The procedure focuses on the decisions required to complete a design. If these decisions are changed, then process alternatives are generated. Some of the decisions affect the exit streams from (and the feeds to) the process, and in some cases these exit streams have an adverse environmental impact. Hence, if we can make decisions, i.e., find alternatives, that do not lead to pollution problems, we can develop "cleaner" processes. The hierarchical decision procedure also can be used to decompose existing designs, and then process alternatives that eliminate existing pollution sources can be identified.