Start
Nov 05, 2009 - 16:00
End
Nov 05, 2009 - 17:30
Venue
Creativity Hall (Room No 118)
Event Type
Speaker
Prof Nitin Kaistha Dept of Chemical Eng. IIT Kanpur
Title
Plantwide Control for Throughput Maximization: A Case Study
ABSTRACT: Issues in plantwide control system design for throughput maximization are considered in this work. The impact of the basic plantwide regulatory control structure and an explicit supervisory optimizing controller on maximizing the throughput is quantitatively evaluated for a simple process module. The module consists of the reaction A + B --> C occurring in a CSTR followed by a distillation column separating the product from the recycled unreacted reactants. The column vapor boilup hitting a maximum acts as the principal bottleneck constraint limiting the throughput due to column flooding. Through an evaluation of four reasonable plantwide control structures the location of the throughput manipulator the composition analyzer for overall component inventory balancing and the local column reflux management policy are shown to significantly affect the maximum throughput. Locating the throughput manipulator close to the bottleneck constraint allows for tighter constraint control using the supervisory optimizing controller minimizing the throughput derating necessary due to disturbances. The effect of the optimizing controller algorithm PI or DMC on the throughput derating is also quantified. Control system design for process operation near multiple bottleneck constraints is also demonstrated. Designing the plantwide regulatory control system to minimize the process variability propagated into the principal bottleneck constraint emerges as the key heuristic from the case study.ABOUT THE SPEAKER: Dr. Nitin Kaistha obtained his B. Tech. in Chemical Engineering from IIT Kanpur in 1996. He followed it up with a PhD from University of Tennessee Knoxville (UTK) in 1999. After brief stints as a Post-Doctoral Fellow at UTK and a Research Scientist at Hindustan Lever Research Center Bangalore he joined IIT Kanpur as Assistant Professor in September 2002. His research interests are in the areas of plantwide control system design reactive distillation design and control and process intensification.