A material flow and economic exchange model to characterize the impact of vehicular changes and policies on the automotive recovery infrastructure.

摘要

Presently, about 95% of all vehicles that retire from the use phase of their life cycle enter the automotive recovery infrastructure. The recycling infrastructure includes the dismantler (or "junk yard") who removes components for reuse, the shredder who recovers the metallic material content, and the non-ferrous operator who separates the non-ferrous stream of the shredder into various non-ferrous material streams. Usually, the cash flows opposite to the flow of materials. The only exception in the automotive recovery infrastructure is when the shredder and the non-ferrous operator pay a tipping fee to the landfill operator to dispose of automotive shredder residue. In the present condition, this "for-profit" recovery infrastructure in U.S. is considered a successful business in terms of environmental sustainability as compared to other products such as home appliance, aluminum cans, and plastic bottles. It recovers approximately 80% of the vehicle by weight mainly because of high ferrous material content in the vehicle. At times in the past, this "for-profit" infrastructure has failed for one reason or another, and vehicles have collected around the country creating an environmental problem. The focus of this dissertation is on characterizing the existing automotive recovery infrastructure using a Material Flow and Economic Exchange model, and then predicting the impact of "on-going" vehicular changes on the infrastructure. The concern is that the original equipment manufacturers are undertaking vehicular changes such as new materials and powertrain technologies that may undermine the profitability of the recycling infrastructure.; The first part of the research involves development of a mathematical basis for the Material Flow and Economic Exchange model. The model is realized using the discrete event simulation software ARENA. The simulation model validation is performed using historical data and information gathered from various business entities in the recovery infrastructure. The second part of the research uses the validated simulation model to study the impact of vehicular material change scenarios, increased levels of dismantling, and increased shredder plastic recovery efficiency on the environmental and economic sustainability of the infrastructure. The analysis is conducted using a 24 experimental design structure. The third part of the research examines strategies that could be employed by the recovery infrastructure to reduce the waste generated below an acceptable level. The acceptable level for the amount of waste generated is based on the recovery targets set by the European Union end-of-life vehicle directive. The impact of these strategies on the environmental and economic sustainability of the recovery infrastructure is investigated. The policies that will ensure the economic sustainability of the infrastructure under these strategies are also studied. The outcome is in terms of suggestions about changes that might be required to achieve the environmental and economic sustainability of the infrastructure.