Transport logistics for a biogas plant : an approach for an optimal collection of manure from local farms by the planned biogas plant Biogas Väst Skaraborg AB

Abstract: Vehicle routing problems (VRPs) are a prevalent concern for businesses that rely on effective logistics to collect and transport items. Biogas Väst, a company that collects liquid manure from local farms and returns residue, is facing a VRP that includes both linehaul and backhaul operations. Biogas Väst's challenges is an inventory routing problem with backhaul (IRPB). This thesis focuses on the construction of a mathematical model based on a version of IRP given by Berg (2020) to address the goal of transporting manure from farms to the biogas plant. Backhaul operations were added to the model, inventory and transportation data was acquired from Biogas Väst to verify relevance to their specific environment. While the resulting model is a simplified version of the real-world problem, it can be used to build heuristics to determine the best routing plan. The research method entailed examining the problem and collecting data from Biogas Väst to inform the model's development. The model was subsequently tested and analysed, demonstrating that some changes is required to make it suitable for Biogas Väst. The thesis's goal is to develop a model which can be used for determining the optimal routing plan, which strives to improve Biogas Väst's logistical operations and overall efficiency. The result for testing the model became 27,3 hours. This was scaled to fit the real case which resulted in a requirement of 3,66 vehicles which drives 13,5 hours daily. The IRPB with linehaul and backhaul is a difficult challenge that necessitates careful consideration of several elements, including vehicle capacity, travel distance, and timing limitations. The mathematical model established in this thesis is a good beginning for approaching a practical solution for this problem, but further effort is needed to produce a practical solution that suits the specific demands of Biogas Väst.