Study On Energy Conservation And Emissions Mitigation In China's Iron And Steel Industry On The Basis Of Dynamic Material Flows Analysis

China's iron and steel industry(CISI)is a typical energy-and emission-intensive industry,facing the issues of the huge amount of energy consumption and emissions,the low proportion of short steel-making route,and excess producing capacity.In previous studies,analyses on steel production,scrap amount,effects of energy saving and emissions mitigation technologies,and energy consumption and emission at industry level,were relatively independent,lack of comprehensive and reasonable analysis process.To study the potential for energy saving and emission mitigation in CISI from 2015 to 2050,a comprehensive assessment approach was developed and applied on the basis of the dynamic Material Flow Analysis(MFA)model,the energy consumption and emission model,Logarithmic Mean Divisia Index(LMDI)decomposition and conservation supply curves(CSC),aiming to provide guidance for the future development of CISI and energy saving and emission mitigation.First,in this thesis,the development of MFA method was reviewed,and the advantages of dynamic MFA were indentified,compared with static MFA.Meanwhile,the lifetime distribution was adopted to calculated obsolete scrap instead of fixed lifetime,and the dynamic MFA model was established with the bottom-up structure of downstream steel-consuming departments,including construction,vehicle,machinery,appliances and other.The results show that China has experienced the peak of steel demand,which will decrease gradually to 440.38 Mt in 2043 and tend to stabilize.The amount of scrap will grow steadily and rapidly from 175 Mt in 2010 to 429 Mt in 2050.On the basis of e-p analysis method for specific energy consumption,the energy consumption and carbon emission prediction model was established.Four scenarios were setted,including business-as-usual(BAU)scenario,the structure adjustment(STA)scenario,the energy-efficiency improvement(EEI)scenario,and the strengthened policy(STP)scenario,to predict the total amounts and intensities of energy consumption and emissions.The results show the reductions are different under each scenario.Furthermore,through LMDI,steel production is the main driving force for the decline in energy consumption and emissions.Besides in short term,energy saving and emissions reduction rely more on the popularization of technology,while in the long term,producing structure adjustment will be dominant.According to the principles of advancement,applicability,and economic feasibility,fourty energy saving and emissions mitigation technologies in CISI were elected to draw CSC.Nineteen,nineteen,and eighteen technologies are cost-effective for SO2,NOx,and dust emissions,respectively.In addition,end-of-pipe control technologies bring huge potential for emission mitigation.The results of sensitive analyses show that discount rate and cost subsidy have large effects on the cost effectiveness of technologies.