Mark Shelley and Mahmoud El-Halwagi

Auburn University

Chemical Engineering Department

Auburn, AL 36849

With the increasingly stringent environmental specifications, there is a growing need for systematic procedures for pollution prevention. To date, most pollution-prevention activities have been undertaken to tackle specific case studies with limited scope of applicability. This approach has restricted the transfer of pollution-prevention expertise from one case to another. Such limitation calls for the development of generally-applicable tools for pollution prevention. The purpose of the seminar is to outline a comprehensive methodology for tackling pollution-prevention problems. This approach is based on a relatively recent development of a new field in integrated process design called mass integration. Mass integration is a holistic approach to the optimal allocation, generation and separation of species throughout the process. It is based on fundamental engineering principles coupled with process integration and systems engineering. An important characteristic of mass integration is its ability to identify performance targets for the whole process ahead of detailed design. Robust performance targets are set for pollution prevention, yield improvement, energy integration and cost effectiveness ahead of design. Trade-offs are made at the targeting stage, allowing the designers to avoid unnecessary design detail. Next, process synthesis methods and chemical engineering tools are employed to systematically make the trade-offs and to realize the targeted performance.

Most petroleum and petrochemical facilities involve the processing of complex hydrocarbon mixtures that are composed of almost infinite number of compounds. Therefore, typical mass integration techniques cannot be readily employed to optimize the generation, allocation, and interception of these numerous species. In this work, we present a novel framework for optimizing complex-hydrocarbon processing facilities. First, new clustering techniques are developed to map the infinite compounds into finite spaces. These finite spaces provide the necessary degrees of freedom for characterizing and optimizing a complex hydrocarbon mixture. The clusters are formed through unique physical transformations that are based on important processing characteristics. Once the clusters are derived, we incorporate them into mass-integration tools such as source-sink mapping and mass-pinch diagrams. In particular, we focus on condensation and allocation of infinite volatile organic compounds (VOCs). The theoretical principles of the work will be presented along with illustration via case studies.