Environmental Benefits Assessment Model On Remanufacturing Process For End-of-life Construction Machinery Products Under Uncertainties

End-of-life engineering machinery products contain many reusable components and a variety of recycled materials.Recycling and remanufacturing of end-of-life engineering machinery products are value-added processes and of great environmental benefits during which the resources can be reused and energy consumption can be reduced.While,different from the original manufacturing,the remanufacturing process is accompanied with many uncertainty factors,for instance,quality uncertainty and human factor uncertainty,which leading to the uncertainties of process routing,process time and the amount of repair materials.And these uncertainties further result in changes in the environmental benefits brought by remanufacturing.However,the existing environmental benefits assessment models for remanufacturing process are failing to reflect these uncertainties factors.Therefore,how to establish a quantitative model under uncertainties to effectively assess environmental benefits of remanufacturing process under the condition of multi remanufactured products remains a problem to be resolved.In the light of the problem mentioned above,this paper chooses end-of-life construction machinery products as study object,and the environmental benefits of remanufacturing process are studied from two aspects:quality uncertainty and human factor uncertainty.And then an environmental benefits assessment model for remanufacturing process under uncertainties is put forward.Validated by a case study,the influence rules of uncertain factors effect on the reduction of carbon emissions were obtained.Specific research contents are as follows:(1)The process of remanufacturing is systematically analyzed,and the process routing of remanufacturing is determined.Consulting a lot of literature,types of carbon emissions and impact factors at each stage are analyzed and summarized.Analyze the uncertain factors in remanufacturing process,and identify the key factors(quality uncertainty,human factor uncertainty).(2)An overall complex quality coefficient measurement method under the condition of multiple remanufactured products is put forward to describe the uncertainty of quality.And the impacts of quality uncertainty of recycled products on carbon emissions in remanufacturing are analyzed,an environmental benefits assessment model with the evaluating indicator "a reduction in carbon emissions”under quality uncertainty is established.Validated by a case study,the result indicates that the amount of the reduction of carbon emission increases with the increasing overall complex quality coefficient and its marginal rising rate decreases gradually;(3)Classify staff efficiency levels,and describe the human uncertain factor with the efficiency grade distribution probability.The impacts of human uncertainty on carbon emissions in remanufacturing are analyzed.An environmental benefits assessment model under human uncertainty with the evaluating indicator "a reduction in carbon emissions" is established.Validated by a case study,the result indicates that the amount of the reduction of carbon emission decreases gradually with the increase of working efficiency until reaches the maximum value,and the change range of carbon emission reduction becomes larger with the increase of the working efficiency factor of the employees,and the rising speed is accelerated.