Design of Closed Loop Supply Chain of Wood Plastic Composite (WPC) Industry

Substituting woody products with wood plastic composite (WPC) products has attracted many interests in recent years. This article seeks to provide an approach to construct a reliable network of closed loop supply chain (CLSC) facilities for WPC industry. The WPC products could be thoroughly collected and recycled and used as raw material for producing new products. In this paper, a mathematical model has been developed that involves deciding direct and reverse flows in the supply chain. The proposed model is mixed Integer linear Programming (MILP) one which minimizes total costs including opening facilities, production, distribution, collection and recycling costs in the forward and reverse sides of the CLSC. The proposed model is applied in a real case of production WPC doors. Sensitivity analysis is performed to evaluate the behavior of the model respect to the changes of the important parameters. The acquired results confirm the applicability of the proposed MILP model in designing real CLSCs.