A Location-Sizing and Routing Model for a Biomethane Production Chain Fed by Municipal Waste

Abstract

Biomethane production from municipal waste is a well-developed technology; however, so far the literature has mainly focused on technical issues forgetting about optimizing the supply chain design or confining it to the first strategic echelon.This paper proposes an integrated approach for a biomethane supply chain from Organic Fraction of Municipal solid Waste (OFMSW), addressing both strategic plant location-sizing and tactical vehicle routing.A two-stage iterative approach following a cluster-first location&sizing&route-second approach is implemented to optimize investment and transportation costs.A novel classification of waste producers into small and large categories allows for a tailored approach, minimizing transportation costs through waste pooling for small producers and allocating vehicles effectively for large producers.Extensive computational experiments on a case study on the Lazio Region demonstrate the cost-effectiveness of the proposed approach, which saves 30% of transportation costs with respect to a location-sizing model. Additionally, the sensitivity analysis highlights the significant impact of including huge-scale plants in the solution.

Keywords: Biomethane, waste management, Circular economy, Location-routing, Mixed Integer Linear Programming