Optimizing solid waste collection in Brussels

This paper reports on a project dealing with waste collection management. A methodology used in this case study combines an operations research method with systems engineering. It illustrates how waste transportation costs are minimized in a major urban area. Due to the complexity of a real size situation, a model is developed to consider a set of points for the collection routes rather than the arcs making up the streets. Several means of transportation including transportation by vehicle, rail and canal are evaluated. Collector vehicles reside overnight in depots and daily evacuate accumulated waste to an incinerator or a transfer station where it is deposited before being shipped out to the incinerator. The latter two sites are called terminal sites. Although optimization models are too difficult to solve with existing means, useful collection strategies are found to give some grounds to decisions made by urban administrators.