Smart and Green Urban Solid Waste Collection Systems: Advances, Challenges, and Perspectives

Abstract

This paper provides a thorough literature review of current state-of-the-art systems analysis techniques for urban solid waste collection and identifies four intrinsic deficiencies of the existing studies over different types of cities. As a demonstration, a multiconstrained and multicompartment routing problem is modeled with roll-on roll-off scheduling strategies in a two-stage decision-making process to exhibit the highest complexity of its kind in practical implementation. The constraints of time windows, intermediate facilities, multishifts, and split deliveries make an ideal combination of all essential complexities in modeling practices. To overcome the relevant challenges, a unified heuristic algorithm is proposed for addressing node routing and roll-on roll-off routing problems. The proposed heuristic algorithm that concatenates initialization and improvement phases solves the models with numerical efficiency to search for the most cost-effective and environmentally benign solutions. Results indicate that differentiated collection increases opportunities to pursue the best routing strategies with sustainable implications through sensitivity analysis at the expense of higher collection costs. The analysis concludes with the perspectives of a smart and green waste collection system designed to create a more sustainable waste management systems in the future.