Carbon Emission Model for A Closed-loop Supply Chain System with Energy Recovery

This paper develops a mathematical model for calculating carbon emissions in a multi-echelon closed-loop supply chain (CLSC) system with energy recovery. The model integrates carbon tax to align the sustainable performance of the CLSC system. This study introduces an energy recovery mechanism that converts consumer waste into alternative energy to enhance the system's sustainability and profitability. The energy from waste is employed in the upstream supply chain as a substitute for a primary energy source. The model includes the cost frameworks related to direct emissions, encompassing transportation and manufacturing activities. The model aims to calculate the amount of emission and its corresponding cost in the CLSC system, considering material recycling and energy recovery. The findings from this study offer several insights for companies aiming to establish more sustainable supply chain practices, promote a circular economy, and minimize carbon emissions. Several findings of this study include: 1.) the integration of energy recovery into the supply chain can be evaluated by calculating the amount of carbon emissions emitted from the shipment of waste and recovered items, the production of energy from waste, and the combustion of energy from waste as a secondary source of energy in the upstream supply chain, 2.) a higher percentage of post-consumer recycled content contributes to a lower total supply chain emission, even though transportation-related emission may slightly increase, 3.) a higher recyclable item rate benefits the system by decreasing the direct emission costs incurred to the supply chain.