Modeling municipal solid waste disposal consortia on a regional scale for present and future scenarios

Abstract

Efficient Waste Management Systems (WMS) management is a global challenge since the waste volume has grown continuously. In WMS Life Cycle Assessment (LCA), collection and transport are the primary environmental and economic impact sources. This study aims to analyze the best inter-municipal consortia configuration for adequate Municipal Solid Waste (MSW) disposal in landfills using Linear Programming (LP) and Mixed Integer Linear Programming (MILP) for the current and future scenarios for the years 2021 and 2033, respectively. It was considered factors such as MSW volume generated by each municipality, transportation distance, and landfill construction cost applied on a regional scale to the Rio Grande do Sul State in Brazil. Our findings appointed a 56% reduction in fuel consumption and carbon dioxide (CO2) emissions for the current scenario of 2021, with annual savings exceeding US$10 million. In addition, the best consortia configuration and the optimal number of landfills were determined for the future scenario, and a 60% reduction in fuel consumption and CO2 emissions was achieved, reaching an annual saving of over US$13 million per year exceeding US$250 million until 2033. In addition to economic savings for municipalities and taxpayers, the optimized WMS would result in environmental and health gains, reducing transport-related CO2 emissions by around 411 thousand tons.