(706b) Opportunity Cost-Based Systematic Process Intensification Under Multiple Objectives
In this work, we propose an optimization formulation that assists in the selection of the best design among several Pareto-optimal solutions. We use an opportunity cost-based approach which considers the trade-offs associated with different objective functions in terms of economic gain. The parameters are market-driven in contrast to the user-defined weights. Multiple objectives such as capital and operating costs, energy consumption, environmental footprint, fresh material acquisition, waste minimization, and safety are accounted for. Furthermore, accounting for the anticipated changes during the design phase itself yields better economic results by reducing the costs associated with future retrofits [4, 6]. The optimization model is also extended to account, from the design phase, for future uncertainties in the regulations, demand shift, and supply constraints. As a result, we can come up with a more flexible and sustainable process configuration. The formulation described can be applied also to retrofit existing designs, but it is best utilized during conceptual design phase, when there is maximum flexibility. The model is incorporated in the building block-based process design and intensification framework which provides plethora of non-intuitive design solutions [7â9]. We demonstrate the capability of the proposed formulation through several case studies with special focus on intensification of energy-intensive separation processes.
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