Scheduling multistage batch plants with sequence‐dependent changeovers

This article deals with the optimal short-term scheduling of multistage batch plants with parallel units and sequence-dependent changeovers, together with the optimal selection of the number and size of batches to be produced. A new resource-task network-based, multiple time-grid continuous-time formulation is proposed that explicitly considers a virtual, shared, intermediate storage unit per stage to keep track of material transfer between processing units belonging to consecutive stages of production. Adequate material transfer is implicitly ensured through mass balances and timing constraints relating the times of event points of dissimilar grids. The new formulation is compared with a conceptually different approach from another research group. The results for several example problems show that the new formulation is tighter, typically requiring fewer event points to find the global optimal solution, and is significantly more efficient computationally. The results also show that for single batch problems other approaches are preferable. © 2009 American Institute of Chemical Engineers AIChE J, 2009

[1]  C. Floudas,et al.  Production Scheduling of a Large-Scale Industrial Batch Plant. I. Short-Term and Medium-Term Scheduling , 2006 .

[2]  Ignacio E. Grossmann,et al.  Decomposition techniques for multistage scheduling problems using mixed-integer and constraint programming methods , 2002 .

[3]  Josef Kallrath,et al.  Planning and scheduling in the process industry , 2002, OR Spectr..

[4]  Jaime Cerdá,et al.  An MILP continuous-time approach to short-term scheduling of resource-constrained multistage flowshop batch facilities , 2001 .

[5]  Pedro M. Castro,et al.  Simultaneous Batching and Scheduling of Single Stage Batch Plants with Parallel Units , 2008 .

[6]  Yu Liu,et al.  Novel continuous-time formulations for scheduling multi-stage batch plants with identical parallel units , 2007, Comput. Chem. Eng..

[7]  R. Sargent,et al.  A general algorithm for short-term scheduling of batch operations */I , 1993 .

[8]  Ignacio E. Grossmann,et al.  Slot-based formulation for the short-term scheduling of multistage, multiproduct batch plants with sequence-dependent changeovers , 2008 .

[9]  Iftekhar A. Karimi,et al.  Scheduling a Two-Stage Multiproduct Process with Limited Product Shelf Life in Intermediate Storage , 2003 .

[10]  Iftekhar A. Karimi,et al.  An Improved MILP Formulation for Scheduling Multiproduct, Multistage Batch Plants , 2003 .

[11]  Iftekhar A. Karimi,et al.  A simpler better slot-based continuous-time formulation for short-term scheduling in multipurpose batch plants , 2005 .

[12]  A. Barbosa‐Póvoa,et al.  Simple Continuous-Time Formulation for Short-Term Scheduling of Batch and Continuous Processes , 2004 .

[13]  Iftekhar A. Karimi,et al.  Scheduling multistage, multiproduct batch plants with nonidentical parallel units and unlimited intermediate storage , 2007 .

[14]  Christodoulos A. Floudas,et al.  Unit-specific event-based continuous-time approach for short-term scheduling of batch plants using RTN framework , 2008, Comput. Chem. Eng..

[15]  N. Giannelos,et al.  A Simple New Continuous-Time Formulation for Short-Term Scheduling of Multipurpose Batch Processes , 2002 .

[16]  Christos T. Maravelias,et al.  Simultaneous Batching and Scheduling in Multistage Multiproduct Processes , 2008 .

[17]  P. Castro,et al.  Short-Term Scheduling of Multistage Batch Plants with Unlimited Intermediate Storage , 2008 .

[18]  Ignacio E. Grossmann,et al.  New general continuous-time state-task network formulation for short-term scheduling of multipurpose batch plants , 2003 .

[19]  Christos T. Maravelias,et al.  Batch selection, assignment and sequencing in multi-stage multi-product processes , 2008, Comput. Chem. Eng..

[20]  Jaime Cerdá,et al.  State-of-the-art review of optimization methods for short-term scheduling of batch processes , 2006, Comput. Chem. Eng..

[21]  Christodoulos A. Floudas,et al.  Enhanced Continuous-Time Unit-Specific Event-Based Formulation for Short-Term Scheduling of Multipurpose Batch Processes: Resource Constraints and Mixed Storage Policies. , 2004 .

[22]  Christodoulos A. Floudas,et al.  Continuous-time versus discrete-time approaches for scheduling of chemical processes: a review , 2004, Comput. Chem. Eng..

[23]  P. Castro,et al.  Two New Continuous-Time Models for the Scheduling of Multistage Batch Plants with Sequence Dependent Changeovers , 2006 .

[24]  Christodoulos A. Floudas,et al.  Continuous-Time Models for Short-Term Scheduling of Multipurpose Batch Plants: A Comparative Study , 2006 .

[25]  Pedro M. Castro,et al.  New Continuous-Time MILP Model for the Short-Term Scheduling of Multistage Batch Plants , 2005 .