Sawmill scheduling: an application-oriented model

Sawmills play a key role in the primary sector of the wood industry producing lumber from tree logs through a multi-stage process including inspections, classification, sawing, drying, etc. The sawing step can become a bottleneck due to the high investment costs the necessary equipment present. Thus, their schedule can be of significant economic importance, resulting in several studies over the years. While most of the approaches in the literature consider a simple model of production and focus on the stochastic nature of real-life problems, present work details a more in-depth model to better tackle practical considerations of less automated and smaller sawmills. The proposed Mixed-Integer Linear Programming model addresses volatile labour availability and differences between the two most dominant sawing technologies. The efficiency of the model is tested on randomly generated instances. The proposed approach can provide the optimal solution within reasonable time for short-term instances.