Research On The Production Planningin In Iron And Steel Remanufacturing Under Carbon Cap-and-trade Regulation

The steel industry,which provides the raw materials for economic development,plays an important role in national economy.However,the extensive growth mode of high energy consumption and emissions in this industry have led to the environmental issues.In recent years,the increasing amount of scrap iron and steel has actively promoted the development of domestic scrap iron and steel remanufacturing.Compared with general steel manufacturing process,the uncertainty of scrap iron and steel recycling,market randomness and the uncertainty of environmental impact make the production decision-making of the scrap iron and steel remanufacturing system more complex,and in this case the traditional production planning tools is not applicable.Besides,China launched a unified national carbon trading market at the end of December 2017.As one of the eight most important emissions industries,the steel industry will become a core member in the carbon trading market,it has a very important theoretical and practical value to study scientifically making a production planning for scrap iron and steel remanufacturing under carbon cap-and-trade regulation.Therefore,our contributions are as two fold: one is achieving a highly coordinated operation between subsystems and full utilization of equipment,and the other is improving the utilization rate of scrap iron and steel scrap and reducing carbon dioxide emissions from enterprises.This paper studies the production planning optimization problems of scrap iron and steel remanufacturing system considering both economic and environmental benefits.Based on the analyse of uncertainty characteristics of the scrap iron and steel remanufacturing system and the impacts of carbon emission policy,we apply operations research,closed-supply chain management theory,probability theory and convex optimization theory to form the best production planning in scrap iron and steel remanufacturing under carbon cap-and-trade regulation from the four perspectives,i.e.backward demand,internal investment,positive demand and the whole system optimization.Main research contents are as follows:Firstly,we review the literature in three aspects,i.e.the remanufacturing production planning under carbon cap-and-trade regulation,the production planning in iron and steel remanufacturing and the production planning in iron and steel remanufacturing under carbon cap-and-trade regulation.To provide theoretical foundation for further research,the main processes and general characteristics of the scrap iron and steel remanufacturing system are analyzed,and the uncertainties in the system and the primary influencing factors of the production planning are summarized.Secondly,we study the production planning in scrap iron and steel remanufacturing considering the scrap iron and steel furnace charge trading under carbon cap-and-trade regulation from demand aspect.It is benefit to effectively distributed the scrap iron and steel furnace charge among enterprises and matching supply and demand of the scrap iron and steel.In this part,we construct a transaction price function based on the yield of scrap iron and steel furnace charge under the yield uncertainties of the scrap iron and steel furnace charge.Combined with the actual tradable situation of the scrap iron,steel furnace charge and production process of the scrap iron and steel remanufacturing,a two-stage stochastic programming method is applied to build the scrap iron and steel remanufacturing production planning model.Then,we can obtain the optimal decision of the scrap iron and steel price,production and trade.We employ some numerical examples are carried out to analyze the impacts of the scrap iron and steel furnace charge yield,scrap iron and steel furnace charge transaction price,carbon cap and carbon price on production decision,total profit and total carbon emissions.It provids some guidance for the scientific and rational formulation of recycling,trading and remanufacturing planning in scrap iron and steel under carbon cap-and-trade regulation.Thirdly,we investigate the production planning in scrap iron and steel remanufacturing considering introducing carbon emission reduction investment under carbon cap-and-trade regulation from internal investment side.First,according to the intrinsic correlation between carbon emission reduction investment and carbon dioxide reduction,the relation function is established.Then,based on the operation characteristics of scrap iron and steel remanufacturing,we build the production planning model to gain maxmum the profit for scrap iron and steel remanufacturing.Third,we analyze the impacts of carbon emission policy on the production planning and carbon emission reduction investment planning,and reveal the condition of the carbon cap-and-trade policy on the production planning.The results show that the investment of carbon emission reduction is beneficial to improve the profit and reduce the carbon emission.Fourth,we explore the production planning in scrap iron and steel remanufacturing considering the carbon emission regulations and demand updating from backward demand side.According to the dynamic characteristics of steel market demand and the production process characteristics of scrap iron and steel remanufacturing,the two-stage stochastic programming method is applied to build a scrap steel remanufacturing production planning model,which is based on the market demand information updating probability.We also proposed a production planning model under the carbon tax policy to compare with the primitive model.The effects of EAF steelmaking cost,carbon price,carbon tax and the probability of low market signal on the optimal production quantity,total profit and total carbon emissions are analyzed by some numerical examples.The results show that carbon cap-and-trade regulations contribute to the realization of high profits and low emissions in scrap iron and steel remanufacturing enterprises.Fifth,considering the uncertainty of recycling and market demand and carbon cap-and-trade regulation,we study the collaborative production planning of scrap iron and steel remanufacturing from the perspective of the whole system optimization.It is useful to coordinate the recycling,reprocessing and remelting subsystems,and market demand.We establish two production planning models by the two-stage stochastic programming,which are designed for two preference situations of low carbon and low smelting cost.So that we obtain the optimal recycling strategy and production strategy.The sensitivity analyses on various problem parameters are discussed with the help of the numerical examples.The results show that increasing short-process steelmaking ratio can meet the economic and environmental benefits.Innovations of this thesis are mainly manifested in the following aspects.(1)The industrial chain,which includes the scrap iron and steel remanufacturing enterprises and scrap iron and steel processing and distribution enterprises,contributing to the trading of scrap iron and steel furnace charge.The existing research literatures rarely investigate the scrap iron and steel furnace charge trading.The transaction price function is constructed,which depends on the yield of scrap iron and steel charge.Then,we analyze the impacts of scrap iron and steel charge trading on the production plan.The obvious innovations are embodied in the research problem and the construction of the model.(2)The steel industry is the key sector of energy conservation and emission reduction,and carbon emissions reduction investment is an effective measure to control carbon dioxide emissions.Unlike previous research literatures,we propose the relation function based on the intrinsic relationship between carbon emission reduction investment and carbon emission reduction.From the perspective of internal investment management,we investigate how to realize the needs of carbon emission reduction and profit for scrap iron and steel remanufacturing enterprises by adjusting production and carbon reduction investment plan under the carbon cap-and-trade regulation.(3)The uncertainties in market demand and carbon emission right are the major factors affecting the production planning of emission-dependent enterprises.Different from existing research,we investigate the optimization of scrap iron and steel remanufacturing production planning considering market demand updating under the carbon cap-and-trade regulation.On the one hand,we introduce the market demand information updating probability,its impacts on production decision are analyzed,and the thresholds value of production decision are obtained;On the other hand,we analyze the effects of carbon emission policy on the utilization of production equipment,and propose the critical conditions of short-process steelmaking.(4)Most of the existing literatures focus on the reprocessing or remelting of scrap iron and steel separately.From the perspective of the whole system optimization,it has certain realistic guiding significance to study the collaborative production planning of scrap iron and steel remanufacturing under two cases of low carbon preference and low smelting cost preference.We consider the three processes of recycling,reprocessing and resmelting of scrap iron and steel remanufacturing.This study can help improve the relevant research theories and methods of scrap iron and steel remanufacturing,and it has important practical significance to help scrap iron and steel remanufacturing enterprises to make reasonable production planning under carbon cap-and-trade regulation.