Optimal Planning of Supply Chains for Multi-Product Generation from Municipal Solid Waste

Abstract

In recent years there has been increased the amount of generated municipal solid waste in most of the developing countries, where the waste management systems are not adequate because of lack of organization and infrastructure. A special case is Mexico, where the municipal solid waste management is responsibility for the government; however, the waste management in Mexico is not adequate due to the lack of landfills and culture about of waste separation. In this regard, this work proposes a mathematical model for the optimal planning of supply chains based on municipal solid waste, where several processing technologies for different waste as well as the total costs for the entire waste management network are considered. This planning problem is mathematically formulated as a multi-objective optimization problem that seeks to maximize the net annual profit (economic objective) and minimize the environmental impact, which is measured through the percentage of the total utilized waste respect to the waste that can be used as raw material. The proposed optimization approach was applied to a case study in Mexico. The results show that it is possible to implement a supply chain for using municipal solid waste that maximizes the net profit of the network reducing significantly the impact to the environment. Furthermore, the results are shown through a Pareto curve that can be used by decision makers to implement a network for waste processing to obtain multiple products in places where there is not any waste management system at all.