Integrated scheduling and dynamic optimization of batch processes using state equipment networks

Abstract

A systematic framework for the integration of short‐term scheduling and dynamic optimization (DO) of batch processes is described. The state equipment network (SEN) is used to represent a process system, where it decomposes the process into two basic kinds of entities: process materials and process units. Mathematical modeling based on the SEN framework invokes both logical disjunctions and operational dynamics; thus the integrated formulation leads to a mixed‐logic dynamic optimization (MLDO) problem. The integrated approach seeks to benefit the overall process performance by incorporating process dynamics into scheduling considerations. The solution procedure of an MLDO problem is also addressed in this article, where MLDO problems are translated into mixed‐integer nonlinear programs using the Big M reformulation and the simultaneous collocation method. Finally, through two case studies, we show advantages of the integrated approach over the conventional recipe‐based scheduling method. © 2012 American Institute of Chemical Engineers AIChE J, 2012

Economic Benefit from Progressive Integration of Scheduling and Control for Continuous Chemical Processes

“…Economic benefit from integrating process dynamics into batch and semi-batch scheduling has also been demonstrated via mixed-logic dynamic optimization in state equipment networks and solution with Benders decomposition in resource task networks [7,39]. Potential for economic benefit from integrating process dynamics into design, scheduling, and control problems has also been demonstrated [41,44,52].…”

“…Traditionally, implementation of process control and scheduling are separated; however, research suggests that opportunity is lost from separate implementation [1][2][3]. Many researchers suggest that economic benefit may arise from integrating production scheduling and process control [4][5][6][7][8][9][10]. Though integration may provide economic benefit, scheduling and control integration presents several challenges which are outlined in multiple reviews on integrated scheduling and control (ISC) [3,[11][12][13][14].…”

Combined Noncyclic Scheduling and Advanced Control for Continuous Chemical Processes

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Application of ANSYS on Screw Type Air Compressor Structure System in Dynamic Optimization

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