A Location Model of Collector in a Multi-Commodity Flow Supply Chain

In this paper, a collector is established in an existing four-tier supply chain network which is composed of suppliers, manufacturers, distributors and consumer markets. The collector is in charge of the dismantling of discarded products, the extraction of raw materials, the final disposal in accordance with the environmental protection requirements, after that, sending the parts can be recycled back to the manufacturer. At each potential site, we develop a network equilibrium model by variational inequality. The behavior of each participant as well as the effect of their interaction in different level is analyzed, and the equilibrium condition of this new system is obtained. This location model put the maximal profits of enterprises as a target, and a stable market price can be obtained, we decide the optimal site by the profit of collector. Finally, a numerical analysis on a test case illustrates the model formulation.