CMI-Based Multi-Period LRIP In Recycling Systems For Scrap Tires

With the continuous improvement of people's living standards and the rapid development of automobile industry, car ownership is increasing rapidly, the generation of waste tires is also greatly accelerated. Environmental pollution and waste of resources caused by waste tires become more serious day by day. So, to promote recycling of waste tires is imperative.To make the waste tires recycled better, the fist task is to recycle waste tires, and the most important thing is to build an efficient operation of the waste tires recycling logistics system. In that system, location of recycling facilities, vehicle routing arrangements and inventory control are three core issues. At present, those three core issues are all solved separately or pairwise integration. In fact, there is a close relationship among facilities location, vehicle routing and inventory control. For example, if facilities are located according to the principle of minimum total system cost, as the total costs including location costs, transportation costs and inventory costs, so the vehicle routing arrangement and inventory control will affect facilities location. On the contrary, the vehicle routing arrangement and inventory control will also be affected by facilities location decision-making. For another example, taking multi-frequency and low-volume collection strategies will increase transportation costs. So, it is necessary to study on integrated (Location-Routing-Inventory Problem, LRIP).At present, only a small number of scholars have studied on LRIP in reverse logistics system optimization. However, they all assumed that each recycling point's all recyclable waste products must be collected in this cycle, not considering the affect of the recycling point's inventory and the collection frequency on the overall system operations. So, this paper based on research at home and abroad, for waste tires recycling system, based on (Collector Managed Inventory, CMI), considered the integrated optimization of recycling centers location, collection vehicle routing arrangements and the inventory control of both recycling points and recycling centers, established a multi-period LRIP optimization model and designed a two-phase algorithm to resolve that model. In addition, based on the same parameter value, compared and analyzed the LRIP optimization results under CMI and non-CMI, indicating that CMI-based approach can significantly optimize the waste tire recycling logistics system, and improve the effectiveness and efficiency of waste tires recycling. This paper list different sizes'total cost and running time under algorithm-1 and algorithm-2, and compared the strengths and weaknesses between algorithm-1 and algorithm-2. By changing the parameters value, this paper also observed the parameter's affect on optimization results of LRIP.This paper based on the same waste tires recycling system, established LRP optimize model, designed a two-phase algorithm, and based on the same parameter value, this paper compared the optimization results of CMI, non-CMI and LRP, found that CMI did get better results. By changing the parameters value, this paper further observed the parameter's affect on optimization results of CMI, non-CMI and LRP.