A multi-objective robust optimization model for site-selection and capacity allocation of municipal solid waste facilities: A case study in Tehran

Abstract

This paper introduces a multi-objective robust optimization model for a municipal solid waste (MSW) management system consisting of customers, transfer stations, landfills, recycle plants, and waste transport vehicles. The proposed model addresses the economic, environmental, and social perspectives of this system simultaneously by minimizing the total cost, the greenhouse gas emission, and the resulting visual pollution, respectively. This model can aid decision makers to locate the optimal sites of MSW recycling and disposal facilities, optimize the capacity allocation of landfills to transfer stations and population centers, optimize the capacity allocation of transfers stations and recycle plants to population centers, determine the most suitable technology for each operation, and find the right number and type of transport vehicles based on aforementioned objectives. Comparing to prior studies, considering all three dimensions of sustainability (i.e. economic, environmental and social) simultaneously, attempting to locate all three major MSW processing and disposal facilities (namely, transfer stations, recycling plants, and landfills) at the same time, and Considering uncertainties involved in this group of facility location problems are the innovations of this study. The proposed model, which is also fully compatible with the waste segregation at source approach, was validated by the use of real data for long-term planning of Tehran's MSW management system by examining five candidate sites for the construction of new facilities. The results show the efficiency of proposed model.