Review of Optimisation Models for Split Pickup and Delivery Problem in Solid Waste Collection System

ASM Sc. J., 20(2), 2025

Published on October 30, 2025

https://doi.org/10.32802/asmscj.2025.1556

Author: Thaeer Mueen Sahib, Rosmiwati Mohd-Mokhtar and Azleena Mohd-Kassim

Abstract

Waste management typically involves technical, climatic, environmental, demographic, socio-economic, and legislative parameters. Such complex nonlinear processes are challenging to model and optimise using fundamental methods. This article reviews optimisation methods for municipal waste collection, concentrating on the Split Pickup and Delivery Problems (SPDP). Throughout our review, a final list of twenty-eight (28) related articles was extracted and investigated to generate new knowledge in the domain of study, which examined several optimisation methods in terms of objectives and constraints related to time, vehicles, and route services, with most variants employed. Based on the review, existing studies have focused on single objective methods with a ratio of 75%, whereby only 25% focused on solving multi-objective problems. Furthermore, the evaluation of optimisation methods to define the knowledge gap, identify the challenges, and provide recommendations were presented by authors that will aid the researchers and serve as a guide for their work. Overall, it is necessary to use real-world data for a more realistic evaluation of SPDP and provide optimal estimation techniques of the uncertain parameter, especially in symmetric and bounded random variables in demand.

Keywords: delivery problem, optimisation methods, Solid waste collection, split of pickup