Integrated production and inventory routing planning of oxygen supply chains

In this work, we address a production and inventory routing problem for liquid oxygen supply chain comprising facilities, distribution network, resources. The key decisions of the involve levels plants, delivery schedule through heterogeneous vehicles, strategies national stock-out prevention. Due to complexity, propose two-level hybrid solution approach that solves using both exact metaheuristic methods. At upper level, develop mixed-integer linear programming (MILP) model determines customer allocation. lower original is reduced several multi-trip vehicle problems by fixing optimal production, inventory, allocation clustering customers. A well-recognised metaheuristic, guided local search method, adapted solve low-level problems. real-world case study in UK illustrates applicability effectiveness proposed optimisation framework. • Integrated planning chains. consisting an MILP metaheuristics proposed. tested on real UK. Sensitivity analysis termination criterion conducted.