Your scrap, my scrap! The flow of scrap materials through international trade

With increasing international trade of secondary materials it is imperative to start including it in our analysis of recycling systems. The goal of this work is to set a materials-flow based foundation to do so. We provide a method for calculating the flow of scrap materials through an interconnected network of international trade. All analysis is presented through the specific example of copper scrap collected in USA, Germany, and Japan, which are leading generators of copper scrap. Results show how the open-economy form can contrast with a closed-economy one, and how different trade networks of the three countries result in different flows, decay rates, and potential recycling returns.