CBE Seminar - Prodromos Daoutidis

Prodromos Daoutidis

Professor and Executive Officer
Department of Chemical and Materials Science
University of Minnesota

Control of Complex Integrated Process Networks

Abstract:

Tight integration is a key enabler towards achieving energy efficiency and sustainability, both in existing chemical plants, but also in emerging technologies for power generation and for production of fuels and chemicals from renewable resources.  Operation and control of tightly integrated plants is, however, challenging, owing to the interactions among the different process units, which limit the effectiveness of classical decentralized control structures. Indeed, the development of control strategies for large scale, tightly coupled networks is a classic problem in control.    

Recent results will be presented which establish that process networks with large rates of material and / or energy recycle, exhibit multi-time-scale dynamics, with individual units evolving in a fast time-scale with weak connections, which become significant over slower time-scales giving rise to a slow evolution of the entire process network. A model reduction framework based on singular perturbations will be described which enables obtaining a hierarchy of low-order nonlinear models valid in the different time-scales. A graph reduction analogue of this framework which can be fully automated will also be described.  This multi-time-scale analysis lends itself naturally to a hierarchical control framework, whereby network-level control objectives can be addressed at a supervisory level using available model-based control designs.  Several illustrative case studies on reaction-separation networks, reactor – heat exchanger networks, heat integrated and thermally coupled distillation columns, and hybrid power production systems will be discussed.  For networks without segregation of material/energy flows due to large rates of recovery and recycle, an alternative approach to their control will be presented. At its heart is the use of hierarchical clustering methods to decompose complex networks into weakly interacting sub-networks, using appropriate notions of distance and compactness. 

Bio:

Prodromos Daoutidis is Professor and Executive Officer in the Department of Chemical Engineering and Materials Science at the University of Minnesota. He received a Diploma degree in Chemical Engineering (1987) from the Aristotle University of Thessaloniki, M.S.E. degrees in Chemical Engineering (1988) and Electrical Engineering: Systems (1991) from the University of Michigan, and a Ph.D. degree in Chemical Engineering (1991) from the University of Michigan. He has been on the faculty at Minnesota since 1992, having served as Director of Graduate Studies in Chemical Engineering (1998-2004) and Chair of the Physical Sciences Policy and Review Council (2000-03), while he has also held a position as Professor at the Aristotle University of Thessaloniki (2004-06). He is the recipient of several research and teaching awards and recognitions, including the NSF CAREER Award, the PSE Model Based Innovation Prize, the Ted Peterson Award of the CAST Division of AIChE, the George Taylor Career Development Award, the McKnight Land Grant Professorship, the Ray D. Johnson / Mayon Plastics Professorship and the Shell Chair at the University of Minnesota. He has also been a Humphrey Institute Policy Fellow. He has served as Program Coordinator in Areas 10B and 10D of the CAST Division of AIChE, and as AIChE Director in AACC. He is the Associate Editor for Process Systems Engineering in the AIChE Journal. He has co-authored four books, over 200 refereed papers, and has supervised 33 graduate students and post-docs, 7 of which currently hold academic positions. His research interests are in design and control of energy systems, process and plant-wide control, control of nonlinear and distributed parameter systems, model reduction, dynamics and control of chemical and biological systems, and control of advanced materials processing.