ENVIRONMENTAL-IMPACT CONSIDERATIONS IN THE OPTIMAL-DESIGN AND SCHEDULING OF BATCH PROCESSES

A systematic methodology for incorporating ecological considerations i n the optimal design and scheduling of batch/semi-continuous processes is presented in this paper. The methodology embeds principles from Li fe Cycle Analysis (LCA) within a general multi-objective formulation f or the design of multipurpose batch plants, with process economics and environmental impact as distinct design objectives. An expanded bound ary is defined around the process of interest, for the consistent eval uation of environmental impact, which is quantified by a set of metric s (for air, water pollution, global warming etc.). Examples from the d airy industry are presented to demonstrate the potential of the method ology to assist in arriving at environmentally friendly and economical ly favourable batch designs and schedules. Issues regarding the use of alternative cleaning and legislation policies on batch operation and design are also discussed. (C) 1997 Elsevier Science Ltd.