Automating hierarchical environmentally-conscious design using integrated software: VOC recovery case study

Traditionally, chemical process design and optimization has mainly been based on economic considerations. Currently, the scope is being extended to include environmentally-conscious process design (ECD). ECD will be facilitated by the emergence of integrated design methodologies and tools. The objectives of this paper are to present a hierarchical design methodology for environmentally-conscious process design, and an integrated assessment and optimization software. An application for the recycle of VOCs from a gaseous waste stream is presented using this design methodology and software. Revenue increased and environmental impacts were reduced. The net present value for the optimum design is approximately $900,000, which is much higher than the base case design, -$2,498,200. A composite environmental index decreases from 1.19 × 10-4 in the base case to about 1.30 × 10-5 in the optimum case. This automated tool along with the embedded design methodology provides an effective and efficient way to perform environmentally-conscious chemical process design and optimization