A CP Approach to the Scheduling of Resource-Constrained Multiproduct Continuous Facilities

Abstract

This contribution presents a new Constraint Programming (CP) formulation to address the optimal operation of multiproduct continuous processes. In particular, facilities having continuous stages, which manufacture intermediate or final products and a limited number of intermediate storage tanks, are tackled. The problem involves finding (i) the optimal sequence of production runs and (ii) the optimal agenda of usage of each storage tank. The proposed formulation is able to handle different features found in industrial environments such as dissimilar machines, sequence-dependent changeover times, forbidden campaign-machine assignments, production runs´ length constraints, etc. Moreover, one of the main contributions of this paper is the handling of constrained resources of various types, such as intermediate storage tanks of limited capacity and qualified manpower required at some stages.