Optimization of the production planning process in a nuts and dried fruits industry

Abstract

A resource-constrained machine scheduling problem is addressed in this paper. The problem arises in an industry located in the Canary Islands (Spain) and is characterized by a set of jobs to be completed on multiple processing lines, where each job has a specific processing time and a sequence-dependent setup time. The objective is to maximize the productivity of the processing lines, subject to constraints such as availability of personnel and processing lines, due dates, precedence order, and setup times, among others. In order to solve this problem, an optimization model that represents the problem as a mixed-integer program is proposed. The paper also introduces a constraint satisfaction heuristic to find near-optimal solutions of the problem. The effectiveness of the proposal is demonstrated through computational experiments on a set of real and synthetic instances, showing that the proposed technique is able to find solutions that are close to the optimal ones within a reasonable amount of time.