Multi-depot green capacitated location routing problem considering uncertainty and in-facility queuing

Nowadays, designing a framework for an environmentally-friendly waste collection network is of higher importance due to population growth. This study presents a multi-depot green capacitated location routing problem (MGCLRP) considering the time window and in-facility queuing under uncertainty. A scenario-based robust optimization is employed to deal with demand and travelling time uncertainties. Moreover, the M/M/c queuing system calculates the expected total wait time at a recycling center. As a solution method, we develop an algorithm to find the optimal number of potential locations and use this optimal number to find the main objectives of the problem. Then, two versions of NSGA-III, enhanced by greedy initializations, are proposed to solve the large-scale instances. The obtained results show the superiority of the proposed NSGA-III over the simple version of this algorithm. Finally, we investigate the applicability of the given model in a practical case study for Tehran.