Multiproduct batch plants design using linear process performance models

Abstract

In this contribution, a novel linear generalized disjunctive programming (LGDP) model is developed for the design of multiproduct batch plants optimizing both process variables and the structure of the plant through the use of process performance models. These models describe unit operations using explicit expressions for the size and time factors as functions of the process variables with the highest impact. To attain a linear formulation, values of the process variables as well as unit sizes are selected from a set of meaningful discrete values provided by the designer. Regarding structural alternatives, both kinds of unit duplications in series and in parallel are considered in this approach. The inclusion of the duplication in series requires different detailed models that depend on the structure selected. Thus, in a new approach for the multiproduct batch plant design, a set of potential structural alternatives for the plant is defined. V V C 2010 American Institute of Chemical Engineers AIChE J, 57: 122-135, 2011 Keywords:LGDP, performance models, multiproduct batch plants, duplication in series IntroductionA large number of optimization models for the design of multiproduct batch plants have been developed over the last decades.1 This kind of plants produces a number of related products using the same equipment in the same operation sequence. Mainly, approaches with constant time and size factors are the most used in the modeling of such plants. [2][3][4][5][6][7][8][9][10][11] Similar approaches using constant factors have also been presented in the field of multipurpose batch plant design. [12][13][14][15][16] However, these models fix the process variables to get a determined process recipe avoiding the evaluation of various economic trade-offs involved in the design decisions. To attain more detailed formulations, process performance models have been included into the design of multiproduct batch plants. The performance models describe size and time factors as a function of the process decision variables (i.e., variables with the highest economic impact on the process) selected for the optimization. Several contributions [17][18][19][20][21][22][23] have tackled performance models instead of fixed recipes to incorporate information about the production process in the plant design. Specifically, the performance models entail additional algebraic equations obtained from mass balances and simplified kinetic equations that describe every unit operation in the process. They may be constant values, an equation, or even a system of equations in accordance with the selected level of detail.In all of the aforementioned problem formulations, the final model is nonlinear and, generally, depending on the proposed representation for the unit operations, nonconvex.Correspondence concerning this article should be addressed to M. S. Moreno at smoreno@santafe-conicet.gov.ar. 122AIChE Journal January 2011 Vol. 57, No. 1 Typically, the most common approach used to solve this problem has been to formulate it as a mixe...

Optimization of a biotechnological multiproduct batch plant design for the manufacture of four different products: A real case scenario

“…The design of multi‐product batch plants using an optimization‐based approach has been studied for more than 40 years and different approaches to deal with the complexity of the optimization models that result in non‐convex mixed‐integer non‐linear problems (MINLP) goes from the development of new algorithms that are able solve these type of problems (Borisenko et al, ; Kocis and Grossmann, ; Li et al, ; Viswanathan and Grossmann, ) to the reformulation of them into mixed‐integer linear problems (MILP) (Moreno and Montagna, ; Sandoval et al, ; Voudouris and Grossmann, ) that can be solved using the known accurate commercial solver CPLEX. In the majority of the cases, the aim of these efforts is to be able to find the optimal design of multi‐product batch plants in real scenarios which is, according to Barbosa‐Póvoa (), still a challenge.…”