An Extended EOQ Model in Production-Recycling System

In this paper, we develop an extended EOQ model with used products recycling and finished products producing to satisfy the fixed demands. This model involves the repair and the continuous collection of used products and allows multiple production lot-sizes problems. Based on the present model, we present a joint policy associating with the collection of used products and the production of finished products under the minimization of total costs of the inventory system, and we deduce simultaneously the optimal economic order quantity of finished products and the optimal inventory level of repairable products models. Finally, we give several numerical examples to illustrate the validity of the models.