Material flow analysis in closed-loop supply chains: modelling of packaging waste recycling at different hierarchical levels

Abstract

Due to recent trends in environmental legislation, closed-loop systems are becoming increasingly important not only for countries and regions, but also for firms that have to fulfill product responsibilities. Therefore, Supply Chain Management (SCM) has to be extended to Closed-Loop Supply Chain Management (CLSCM). As a quantitative basis, Material Flow Analysis helps to structure the complex cyclic network and to map several processes. The article describes an approach to the modelling of cyclic systems at different hierarchical levels, using the packaging recycling system as an example. It gradually refines a general closed-loop framework into material flow charts (top down procedure). Additionally, it offers elementary models for building up transformation networks (bottom-up procedure). These building blocks are distinguished by transformation type and process flexibility and can be linked directly to optimising operations research models.