(635a) Process Integration as An Enabling Tool in Environmental Impact Assessment

Environmental impact assessment EIA is one of the most commonly used tools employed to evaluate the ecological consequences of new projects and design retrofits. It spans various spatial and temporal time scales. In addition to the analysis provided by EIA, it is used as a driving force for revisiting environmentally-undesirable designs. Various design alternatives are typically proposed to mitigate the environmental effects of the original design. The generation of these design alternatives is normally carried out based on brainstorming, evolutionary techniques, and heuristics. Given the numerous potential design alternatives, such approaches are not guaranteed to provide an optimum or near-optimum solution except in simple cases. The purpose of this paper is to introduce process integration as a systematic framework and an enabling tool for generating design alternatives within the EIA. A generic representation is developed to capture the environmental performance of the process while embedding all design configurations of interest. Next, process integration tools are used to target and screen design alternatives. The multiple scales associated with the micro-, meso-, and macro-scales of the problem (e.g., molecular, unit, process, and environment) are addressed The problem is then formulated as an optimization problem that seeks to minimize the cost of the design modification (or the new project) while complying with the relevant environmental metrics used in the EIA. Hierarchical solution techniques are used to attain a cost-effective solution and to rank the list of generated alternatives. A case study is solved to show the uniqueness and effectiveness of the new approach.