The multi-trip vehicle routing problem with increasing profits for the blood transportation: An iterated local search metaheuristic

This paper studies a multi-trip routing problem of a shuttle fleet to transport blood units from collection sites to a blood center. In this problem, the blood units intended to produce platelets and cryoprecipitate must be processed within eight hours from their donation and arrive at the blood center at a time less than its closing time to guarantee enough processing time. Since it is assumed that blood units are donated at a collection site following a constant ratio over its operating hours, this problem is modeled as a multi-trip vehicle routing problem with increasing profits for which a mixed-integer linear programming formulation is proposed. A hybrid iterated local search metaheuristic and an extended version are developed as solution methods. The extended version includes a mixed-integer linear programming component into the local search of the hybrid metaheuristic to optimize the decision on the departure times of the trips. The solution methods are tested on a new set of instances based on the blood collection system of Bogota, Colombia. •The problem formalization and its mathematical programming model are included.•Whole blood to get blood components and time limits to process platelets are studied.•A metaheuristic and a matheuristic are proposed as solution methods.•A new set of instances based on a real-world case is presented.•Tests validate the applicability of the methods and provide the best-known solutions.