Plant-Wide Waste Management. 1. Synthesis and Multiobjective Design

Abstract

Combinatorial process synthesis is a novel paradigm for flow sheet synthesis. Its two-staged synthesis algorithm generates all feasible operational alternatives followed by rigorous optimization of structurally superior flowsheets. In the conventional practice, process synthesis aims at minimizing total annualized cost. However, designs with maximum economic performance may cause unbalanced environmental impact. It should not be surprising that subsequent cleanup and waste treatment efforts often compound actual process overhead unaccounted for in the traditional design philosophy. Therefore, environmental considerations should be accommodated alongside economic performance. In this first paper of a triple series, we will introduce the concept of combinatorial process synthesis for developing plant-wide recovery and treatment policies for batch manufacturing sites. The flow sheet generation step combined with multiobjective optimization will render operating policies with optimal trade-off among the conflicting objectives cost and environmental impact. The discussion includes case studies illustrating the systematic and fully automatic waste management procedure.