INTEC   05402
INSTITUTO DE DESARROLLO TECNOLOGICO PARA LA INDUSTRIA QUIMICA
Unidad Ejecutora - UE
capítulos de libros
Título:
A novel approach to lot-sizing and scheduling of multistage batch
Autor/es:
MARCHETTI, PABLO A.; MÉNDEZ, CARLOS A.; CERDÁ, JAIME
Libro:
Proceedings of XVIII Congreso Brasileño de Ingeniería Química
Editorial:
Asociación Ingenieros Químicos - Brasil
Referencias:
Año: 2010; p. 1029 - 1038
Resumen:
This work presents a pair of MILP continuous-time formulations to
address the combined lot-sizing and scheduling of multi-product batch plants with
multiple processing stages. The proposed mathematical models can handle multiple
orders per product with different due dates as well as variable processing times. A predefined
set of batches for each order with enough elements to guarantee optimality is
initially proposed. Batch integrity is preserved throughout the entire processing sequence,
but a lot of final product can be split to satisfy two or more orders. Both MILP
formulations use a precedence-based continuous-time representation, but deal with batch
allocation and sequencing decisions in a different manner. The first model rigorously
arranges individual batches assigned to the same unit, while the second sequences
clusters of batches featuring the same product, due-date, and processing route. In the
latter formulation, final contents of clusters are model decisions. Effective symmetry
breaking constraints based on allocation variables to avoid redundant solutions were also
developed. The proposed formulations were applied to several examples, yielding very
good results at quite competitive CPU times.