Retrofit of complex and energy intensive processes

Abstract Thermodynamic methods of process synthesis are very useful for the design of complex and energy intensive processes, but they cannot be used simultaneously with material balances. Algorithmic methods are simultaneous, but they are difficult to solve for complex and energy intensive processes because the number of variables increases with the number of combinations. We can approach the optimal design for complex and energy intensive processes if we combine the two methods. The combined approach is composed of two steps, the thermodynamic and the algorithmic one. In the first one we eliminate unpromising structures and we include new, potentially good ones by studying an Extended Grand Composite Curve. In the second one we can optimize the superstructure obtained by using Mixed-Integer Nonlinear Programming. The combined approach can be used for optimal design of energy and material parameters of continuous processes as well as for energy recovery. In a retrofit case study we have targeted energy saving using rigorous models and fixed amount flow rates to find two promising structures, and then we have used parameter and simultaneous structural optimization to determine the best alternative and its parameters.

[1]  Ignacio E. Grossmann,et al.  A structural optimization approach in process synthesis—I: Utility systems , 1983 .

[2]  Z. Kravanja,et al.  Heat integration of reactors—I. Criteria for the placement of reactors into process flowsheet , 1988 .

[3]  Ignacio E. Grossmann,et al.  Simultaneous optimization models for heat integration—I. Area and energy targeting and modeling of multi-stream exchangers , 1990 .

[4]  Peter Mizsey,et al.  Toward a more realistic overall process synthesis—the combined approach , 1990 .

[5]  Ignacio E. Grossmann,et al.  Simultaneous optimization and heat integration with process simulators , 1988 .

[6]  P. Glavic,et al.  Completely analyze energy-integrated processes , 1993 .

[7]  B. Linnhoff,et al.  The design of separators in the context of overall processes , 1988 .

[8]  Christodoulos A. Floudas,et al.  Automatic synthesis of optimum heat exchanger network configurations , 1986 .

[9]  B. Linnhoff,et al.  Supertargeting; Optimum synthesis of energy management systems , 1989 .

[10]  Ignacio E. Grossmann,et al.  Computational experience with dicopt solving MINLP problems in process systems engineering , 1989 .

[11]  Arthur W. Westerberg,et al.  A Simple Synthesis Method Based on Utility Bounding for Heat‐Integrated Distillation Sequences , 1985 .

[12]  Ignacio E. Grossmann,et al.  Simultaneous optimization models for heat integration—II. Heat exchanger network synthesis , 1990 .

[13]  John J. McKetta,et al.  Encyclopedia of Chemical Processing and Design , 1976 .

[14]  I. Grossmann,et al.  A mixed-integer nonlinear programming algorithm for process systems synthesis , 1986 .

[15]  Bodo Linnhoff,et al.  Cost optimum heat exchanger networks—1. Minimum energy and capital using simple models for capital cost , 1990 .

[16]  Bodo Linnhoff,et al.  Using pinch technology for process retrofit , 1986 .

[17]  Bodo Linnhoff,et al.  A User guide on process integration for the efficient use of energy , 1994 .

[18]  James M. Douglas,et al.  A hierarchical decision procedure for process synthesis , 1985 .

[19]  B. Linnhoff,et al.  Supertargeting; Different process structures for different economics , 1989 .

[20]  Christodoulos A. Floudas,et al.  A retrofit approach for heat exchanger networks , 1989 .

[21]  C. Floudas,et al.  A mixed integer nonlinear programming model for retrofitting heat-exchanger networks , 1990 .

[22]  I. Grossmann,et al.  Relaxation strategy for the structural optimization of process flow sheets , 1987 .

[23]  Peter Mizsey,et al.  A predictor-based bounding strategy for synthesizing energy integrated total flowsheets , 1990 .

[24]  Kristian M. Lien,et al.  Decomposed algorithmic synthesis of reactor-separation-recycle systems , 1993 .

[25]  S. Ahmad,et al.  Total site heat integration using the utility system , 1994 .

[26]  David Kendrick,et al.  GAMS, a user's guide , 1988, SGNM.

[27]  James M. Douglas,et al.  A systematic procedure for retrofitting chemical plants to operate utilizing different reaction paths , 1990 .