



Process synthesis
Our aim in process synthesis is to develop systematic design optimization methods for selecting configurations and operating conditions in process systems, including metabolic networks. The major thrust in the work is to develop superstructure representations at various levels of abstraction (aggregated to detailed), model the corresponding optimization problems, and develop effective solution techniques and strategies for these problems (MINLP, MILP, Disjunctive Programming).
Areas of application include synthesis of energy systems, integrated process water systems, complex distillation systems, process flowsheets and metabolic networks.
Software:
MAGNETS  SYNHEAT  GLOBESEP  PROSYN
Representative publications:
Barttfeld, M., P.A. Aguirre and I.E. Grossmann, "Alternative Representations and Formulations for the Economic Optimization of Multicomponent Distillation Columns," Computers and Chemical Engineering 27, 363383 (2003).
Bruno, J.C., F. Fernandez, F. Castells and I.E. Grossmann, "MINLP Model for Optimal Synthesis and Operation of Utility Plants", Transaction of the Institution of Chemical Engineers , 76, pp.246258 (1998).
Caballero, J.A. and I.E. Grossmann, "Aggregated Models for Integrated Distillation Systems," I&EC Research , 38, 23302344 (1999).
Daichendt, M.M. and I.E. Grossmann, "Integration of Hierarchical Decomposition and Mathematical Programming for the Synthesis of Process Flowsheets," Computers and Chemical Engineering , 22, 147175 (1998).
Duran, M.A. and I.E. Grossmann, "Simultaneous Optimization and Heat Integration of Chemical Processes," AIChE J. 32, 123 (1986).
Floudas, C.A., A.R. Ciric and I.E. Grossmann, "Automatic Synthesis of Optimal Heat Exchanger Network Configurations," AIChE J. 32, 276 (1986).
Galan, B. and I.E. Grossmann, "Optimal Design of Distributed Wastewater Treatment Networks," Ind.Eng.Chem. Res. 37, 40364048 (1998).
Grossmann, I.E., J.A. Caballero and H. Yeomans, "Advances in Mathematical Programming for Automated Design, Integration and Operation of Chemical Processes," Proceedings of the International Conference on Process Integration (PI'99), Copenhagen, Denmark (1999).
Jackson, J. and I.E. Grossmann, "A Disjunctive Programming Approach for the Optimal Design of Reactive Distillation Columns, Computers and Chemical Engineering 25, 166111673 (2001).
Kravanja Z. and I.E. Grossmann, "New developments and capabilities in PROSYN an automated topology and parameter process synthesizer", Computers Chem. Engng,, 18, 10971114 (1994).
Lee, S., C. Phalakornkule, M.D. Domach and I.E. Grossmann, "Recursive MILP Model for finding all the Alternate Optima in LP models for Metabolic Networks," Computers and Chemical Engineering 24, 711716 (2000).
Papoulias, S.A. and I.E. Grossmann, "A Structural Optimization Approach in Process Synthesis. Part I: Utility Systems," Part II: Heat Recovery Networks," Part III: Total Processing Systems," Computers and Chemical Engineering 7, 695 (1983).
Turkay, M. and I.E. Grossmann, "Structural Flowsheet Optimization with Complex Investment Cost Functions", Computers and Chemical Engineering 22, 673686 (1998).
Viswanathan, J. and I.E. Grossmann, "Optimal Feed Locations and Number of Trays for Distillation Columns with Multiple Feeds," I&EC Research, 32, 29422949 (1993).
Yee, T.F., I.E. Grossmann and Z. Kravanja, "Simultaneous Optimization Models for Heat Integration. I. Energy and Area Targeting. II. Synthesis of Heat Exchanger Networks,". III. Optimization of Process Flowsheets and Heat Exchanger Networks," Computers and Chemical Engineering 14, 1151 (1990).
Yeomans, H. and I.E. Grossmann, "A Systematic Modeling Framework of Superstructure Optimization in Process Synthesis," Computers and Chemical Engineering , 23, 709731 (1999).
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Planning
Our aim in the area of planning is to develop multiperiod mixedinteger optimization models (MILP, MINLP, Disjunctive Programming) for the optimization of longrange term decisions for investment and supply chain management. Decomposition methods and aggregated models for discrete uncertainties are being investigated.
Our major areas of concentration are process networks, utility plants, gas and oil exploration systems, product development in pharmaceutical and agrochemicals.
Software:
PLANNER  FLEXPLAN  MULTISITE  GREENPLAN
Representative publications:
Bok, JK, I.E. Grossmann and S. Park, "Supply Chain Optimization in Continuous Flexible Process Networks", I&EC Research 39, 12791290 (2000). Iyer, R. and I.E. Grossmann, "Synthesis and Operational Planning of Utility Systems for Multiperiod Operation", Computers and Chemical Engineering 22, 979993 (1998). Jackson, J. and Ignacio E. Grossmann, "A Temporal Decomposition Scheme for Nonlinear Multisite Production Planning and Distribution Models," I&EC Research, 42, 30453055 (2003). Lee, H., J.M. Pinto, I.E. Grossmann and S. Park, "MILP Model for Refinery Short Term Scheduling of Crude Oil Unloading with Inventory Management", I&EC Research, 35, 16301641 (1996). Maravelias, C.T. and I.E. Grossmann, "Simultaneous Planning for New Product Development and Batch Manufacturing Facilities," I&EC Research 40, 61476164 (2001). Norton, L.C. and I.E. Grossmann, "Strategic Planning Model for Complete Process Flexibility," Ind.Eng.Chem.Res., 33, 6976 (1994). Perea, E., I.E. Grossmann, E. Ydstie, and T. Tahmassebi, "Dynamic Modeling and Decentralized Control of Supply Chains," Ind.Eng.Chem. Research 40, 33693383 (2001). Sahinidis, N., I.E. Grossmann, R.E. Fornari and M. Chatrathi, "Optimization Model for Long Range Planning in the Chemical Industry," Computers and Chemical Engineering 13, 1049 (1989). Van den Heever, S.A., and I.E. Grossmann, "An Iterative Aggregation/Disaggregation Approach for the Solution of a Mixed Integer Nonlinear Oilfield Infrastructure Planning Model," I&EC Research 39, 19551971 (2000).
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Scheduling
Our aim in the area of process scheduling is to develop effective discrete optimization models and solution strategies (MILP, MINLP, Disjunctive Programming, Hybrid MILP/Constraint Programming) that exploit the structure of short term and cyclic scheduling problems of multiproduct batch and continuous processes.
In addition, we are concerned with the scheduling of tests for new product development (agrochemicals and pharmaceuticals). Software:
STBS  CYCLE  PARALLEL  MULTISTAGE  BATCHSPC  BATCHMPC  PRODEV
Representative publications:
Birewar, D. and I.E. Grossmann, "Efficient Optimization Algorithms for ZeroWait Scheduling of Multiproduct Batch Plants," Ind. Eng. Chem. Res. 28, 1333 (1989). Jain, V. and I.E. Grossmann, "Cyclic Scheduling and Maintenance of Parallel Process Units with Decaying Performance", AIChE J., 44, pp. 16231636 (1998) Jain, V. and I.E. Grossmann, "Resource Constrained Scheduling of Tests in New Product Development," accepted for publication Ind.Eng.Chem. Res. (1999) . Maravelias, C.T. and I.E. Grossmann, "A New General ContinuousTime State Task Network Formulation for Short Term, Scheduling of Multipurpose Batch Plants," I&EC Research, 42, 30563074(2003). Maravelias, C.T. and I.E. Grossmann, "Minimization of Makespan with DiscreteTime StateTask Network Formulation," Ind. Eng. Chem. Res, 42, 62526257 (2003). Maravelias, C.T. and I. E. Grossmann, "A Hybrid MILP/CP Decomposition Approach for the Continuous Time Scheduling of Multipurpose Batch Plants," to appear in Computers and Chemical Engineering (2004). Pinto, J. and I.E. Grossmann, "A Continuous Time MILP Model for Short Term Batch Scheduling of Multistage Batch Plants", I&EC Research , 34, 30373051 (1995). Pinto, J.M. and I.E Grossmann, "A Logic Based Approach to Scheduling Problems with Resource Constraints", Computers and Chemical Engineering , 21, 801808(1997). Schmidt, C.W. and I.E. Grossmann, "Optimization Models for the Scheduling of Testing Tasks in New Product Development", Ind.Eng.Chem. Res. 35, 34983510 (1996). Schmidt, C.W. and I.E. Grossmann, "The Exact Overall Time Distribution of a Project with Uncertain Task Durations," Eur. J. of Opns. Res., 126, 614636 (2000). Sahinidis, N.V. and I.E. Grossmann, "MINLP Model for Cyclic Multiproduct Scheduling on Continuous Parallel Lines," Computers and Chemical Engineering 15, 85 (1991). Voudouris, V.T. and I.E. Grossmann, "Optimal Synthesis of Multiproduct Batch Plants with Cyclic Scheduling and Inventory Considerations," I&EC Research, 32, 19621980 (1993).
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Uncertainty
The handling of uncertainties in process synthesis, planning and scheduling is being addressed in our research work. Uncertainties in process parameters are evaluated through flexibility analysis, and through stochastic programming. Uncertain demands are considered in planning problems, and uncertain time duration in scheduling problems. Representative publications:
Balasubramanian and I.E. Grossmann, "A Novel Branch and Bound Algorithm for Scheduling Flowshop Plants with Uncertain Processing Times," Computers and Chemical Engineering 26, 4157 (2002).
Balasubramanian, J. and I. E. Grossmann, "Approximation to Multistage Stochastic Optimization in Multiperiod Batch Plant Scheduling under Demand Uncertainty," I&EC Research 43, 36953713 (2004).
Clay, R.L. and I.E. Grossmann, "A Disaggregation Algorithm for the Optimization of Stochastic Production Planning Models," Computers and Chemical Engineering 21, 751774 (1997).
Goel, V. and I.E. Grossmann, ""A Stochastic Programming Approach to Planning of Offshore Gas Field Developments under Uncertainty in Reserves", Computers and Chemical Engineering, 28, 14091429 (2004).
Grossmann, I.E. and C.A. Floudas, "Active Constraint Strategy for Flexibility Analysis in Chemical Processes," Computers and Chemical Engineering 11, 675 (1987).
Pistikopoulos, E.N. and I.E. Grossmann, "Optimal Retrofit Design for Improving Process FlexibilityLinear Systems," Computers and Chemical Engineering 12, 719 (1988).
Schmidt, C.W. and I.E. Grossmann, "The Exact Overall Time Distribution of a Project with Uncertain Task Duration," accepted for publication Eur. J. of Opns. Res. (1998)
Straub, D.A. and I.E. Grossmann, "Design Optimization of Stochastic Flexibility," Computers and Chemical Engineering, 17, 339 (1993).
Swaney, R.E. and I.E. Grossmann, "An Index for Operational Flexibility in Chemical Process Design. Part I: Formulation and Theory,". Part II: Computational Algorithms," AIChE J. 31, 621 (1985).
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Mixedinteger linear and non linear programming
Our aim in this area is to develop novel model representations, and novel solution methods for the optimization of problems involving discrete and continuous variables. For the case of MILP problems we have developed branch and bound methods that incorporate logic inference to reduce the number of nodes that need to be enumerated. In the case of MINLP problems we have developed outerapproximation methods for problems that involve linear discrete variables and nonlinear continuous variables, and which have been implemented in DICOPT within the GAMS modeling system. In addition, areas of current research include generalized disjunctive programming, global optimization and multiperiod optimization.
Representative publications:
Duran, M.A. and I.E. Grossmann, "An OuterApproximation Algorithm for a Class of Mixedinteger Nonlinear Programs," Math Programming 36, 307 (1986). Grossmann, I.E., "Review of Nonlinear MixedInteger and Disjunctive Programming Techniques," Optimization and Engineering, 3, 227252 (2002). Jain, V. and I. E. Grossmann, "Algorithms for Hybrid MILP/CP Models for a Class of Optimization Problems ", INFORMS Journal of Computing, 13, 258276 (2001) Kocis, G.R. and I.E. Grossmann, "Relaxation Strategy for the Structural Optimization of Process Flowsheets," Ind. Eng. Chem. Res. 26, 1869 (1987). Quesada, I. and I.E. Grossmann, "An LP/NLP Based Branch and Bound Algorithm for MINLP Optimization," Computers and Chemical Engineering, 16, 937 (1992). Raman, R. and I.E. Grossmann, "Symbolic Integration of Logic in Mixed Integer Linear Programming Techniques for Process Synthesis," Computers and Chemical Engineering, 17, 909 (1993). Sahinidis, N.V. and I.E. Grossmann, "Convergence Properties of Generalized Benders Decomposition," Computers and Chemical Engineering, 15, 481 (1991). Viswanathan, J. and I.E. Grossmann, "A Combined Penalty Function and Outer Approximation Method for MINLP Optimization," Computers and Chemical Engineering 14, 769 (1990).
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General Disjunctive Programming
In contrast to the algebraic representations of MINLP models, GDP models are expressed in terms of boolean and continuous variables and involve an objective function, global constraints, and constraints expressed with disjunctions with OR operators, and logic propositions. Solution algorithms include the logicbased outerapproximation method and nonlinear convex hull based branch and bound. The former has been implemented in the code LOGMIP. Representative publications:
Grossmann, I.E. and S. Lee, "Generalized Disjunctive Programming: Nonlinear Convex Hull Relaxation and Algorithms", Computational Optimization and Applications 26, 83100(2003).
Grossmann, I.E. and M. Turkay, "Solution of Algebraic Systems of Disjunctive Equations", Computers and Chemical Engineering, 20, S339S334 (1996). Lee, S. and I.E. Grossmann, "New Algorithms for Generalized Disjunctive Programming: ", Computers and Chemical Engineering 24, 21252141 (2000). Raman, R. and I.E. Grossmann, "Modeling and Computational Techniques for Logic Based Integer Programming," Computers and Chemical Engineering, 18, 563 (1994). Vecchietti, A. and I.E. Grossmann, "LOGMIP: A Disjunctive 01 Nonlinear Optimizer for Process Systems Models, Computers and Chemical Engineering 23, 55556 (1999). Vecchietti, A., S. Lee and I.E. Grossmann, "Modeling of Discrete/Continuous Optimization Problems: Characterization and Formulation of Disjunctions and their Relaxations," Computers and Chemical Engineering 27, 433448 (2003). Sawaya, N.W. and I.E. Grossmann, "A Cutting Plane Method for Solving Linear Generalized Disjunctive Programming Problems," submitted for publication (2004). Turkay, M. and I.E. Grossmann, "LogicBased MINLP Algorithms For the Optimal Synthesis Of Process Networks," Computers and Chemical Engineering , 20, 959978 (1996).
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Global optimization
Our aim has been to address NLP, MINLP and GDP problems that exhibit special algebraic structures. These include problems with bilinear, linear fractional and separable concave functions, and are motivated by problems in the heat exchange and separations areas. The basic approach relies on developing valid underestimates which are incorporated within a spatial branch and bound enumeration method.
Representative publications:
Bergamini, M.L., P. Aguirre and I.E. Grossmann, "Logic Based Outer Approximation for Global Optimization of Synthesis of Process Networks," submitted for publication (2004)
Lee, S. and I.E. Grossmann, "A Global Optimization Algorithm for Nonconvex Generalized Disjunctive Programming and Applications to Process Systems, " Computers and Chemical Engineering 25, 16751697 (2001).
Quesada, I. and I.E. Grossmann, "Global Optimization of Bilinear Process Networks with Multicomponent Streams," Computers Chem. Engng,, 19, 12191242 (1995). Quesada, I.E. and I.E. Grossmann, "A Global Optimization Algorithm for Linear Fractional and Bilinear Programs," Journal of Global Optimization, 6, 3976 (1995). Zamora, J.M. and I.E. Grossmann, "A Branch and Contract Algorithm for Problems with Concave Univariate, Bilinear and Linear Fractional Terms," accepted for publication, Journal of Gobal Optimization 14, 217249 (1999) Zamora, J.M. and I.E. Grossmann, "Continuous Global Optimization of Structured Process System Models", Computers and Chemical Engineering 22, 17491770 (1998).
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Multiperiod Optimization
Our aim is to develop general models for selecting process configuration, capacity expansion and discrete operation of units. Generalized Disjunctive Programming is being used for this purpose, for which decomposition methods are developed.
Representative publications:
Sahinidis, N.V. and I.E. Grossmann, "Reformulation of the Multiperiod MILP Model for Capacity Expansion of Chemical Processes," Operations Research 40(Supp. 1), S127S144 (1992).
Varvarezos, D.K., I.E. Grossmann and L.T. Biegler, "An Outer Approximation Method for Multiperiod Design Optimization, Ind. Eng. Chem. Research 31 14661477 (1992).
Varvarezos, D., L. T. Biegler and I.E. Grossmann, "Modeling Uncertainty and Analyzing Bottleneck Characteristics in Multiperiod Design Optimization", Computers and Chemical Engineering, 19, 497511 (1995).
Van den Heever, S.A. and I.E. Grossmann, "Disjunctive Multiperiod
Optimization Methods for Design and Planning of Chemical Process Systems," Computers and Chemical Engineering, 23, 10751095 (1999).
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