(519a) Incorporating Sustainability Into the Design of Chemical Process: From Reaction Pathway Selection to Process Design

It is important to incorporate sustainability issues into the design of chemical process, as more and more social and environmental concerns arise, and natural resources become costly and less available.  Sustainability is multi-dimensional and complex in nature, as economic, societal and environmental issues need to be considered together.  Thus a structured approach is needed to assist in incorporating sustainability into the new process design, as well as the retrofit of an existing design.  In this paper, a sequential approach from reaction pathway selection to process design is proposed, in light of sustainability.  At the early design stage, the sustainability performance of each potential reaction pathway is evaluated in terms of possible profit, driving force of the pathway (Gibbs energy), inherent safety index, environmental analysis, mass efficiency, reaction selectivity and conversion, respectively.  This can help the designers to screen out the inferior reaction alternatives systematically and efficiently, thus reduce the complexity and labor in the following design stage.  Then in the detailed process design stage, the sustainability performance of each process is assessed sequentially considering economic, societal, environmental and efficiency issues.

Root cause analysis is a powerful tool to identify and illustrate the fundamental cause of a problem.  Integrating root cause analysis into the presented sequential sustainable design approach can help identify the root cause and improvement opportunity for a specific design.  The idea of this approach is illustrated via several case studies.