Research On Multi-stage CO₂ Emission Characteristics And Peak Path Of Iron And Steel Industry In Jilin Province

In order to make a contribution to limiting global-mean temperature rise to 1.5?announced in the Paris Agreement,the Chinese government has promised to peak carbon emissions no later than 2030 and achieve Carbon Neutrality by 2060.It is essential to seek socioeconomic development in a low-carbon way for achieving these two ambitious goals.As the significant industrial sector for supporting industrialization and urbanization,iron and steel industry contributed 20%of total CO₂ emissions of China.Therefore,it is extremely critical to investirgate carbon emissions in manufacturing processes of iron and steel industry and explore the pathways for Carbon Peak and Carbon Neutrality,so as to facilitate the realization of 1.5?target and China's carbon peak and carbon neutralization target.This paper takes multi-stage CO₂ emission characteristics and carbon peak path of iron and steel industry as the research object.An integrated LCA-LEAP model is developed by combining the life cycle assessment(LCA)and long-range energy alternatives planning(LEAP)models.Three scenarios are set up including the business as usual scenario(BAU),the new policy scenario(NPS),and the low-carbon scenario(LCS).The model is used to systematically measure the CO₂ emissions of various stages and technologies of iron and steel production for the period 2020-2030.The CO₂emissions resulting from different energy use in each process at each stage of the iron and steel production life cycle are quantified.The CO₂ emission reduction rate of introducing five measures in the iron and steel production lifecycle,namely equipment large-scaling,increasing penetration of electric arc furnace technique,application of hydrogen reduction ironmaking technology,technology upgrading and energy structure change,are evaluated and analyzed at different application levels.Finally,potential paths for future low-carbon development in the steel industry are proposed based on the study results.The results of the study indicate that:(1)BAU will peak at 30.71 Mt in 2027 and gradually decline to 26.93 Mt in 2030.NPS will peak at 29.02 Mt in 2025 and then drop to 24.75 Mt in 2030.LCS will peak at 27.33 Mt in 2023 and fall to 23.18 Mt in 2030.The carbon emissions per ton of steel in the NPS and LCS will decrease by 8.08%and 13.90%,respectively,compared to the base year.The three scenarios have different peak years for CO₂ emissions,but all show an upward and then downward trend.BAU simulates the current level of technology in the iron and steel industry and will peak in 2027.In NPS and LCS,the peak value of CO₂ emissions will decrease in advance due to the gradual introduction of hydrogen-reduction ironmaking technology,increasing the proportion of electric arc furnaces,and equipment large-scaling.(2)The iron and steel industry consist of four stages:raw material acquisition,material processing,manufacturing and recycling.In the multi-stage carbon emissions of the iron and steel industry,the material processing stage uses the most fossil energy,accounting for 80.67%-86.55%of the total CO₂ emissions,which is mainly due to the high energy consumption of blast furnace ironmaking in the ironmaking process of the material processing stage.CO₂ emission ranks behind material processing in the manufacturing stage(10.81%-16.53%),raw material acquisition stage(2.31%-2.49%)and recycling stage(0.15%-0.45%).From the perspective of energy consumption types,the three scenarios emit the most CO₂ from the use of cleaned coal in iron and steel production,accounting for more than 20%,followed by anthracite,coal gas and electricity.(3)Different measures have different carbon emission reduction effects,and Equipment large-scaling measures have the largest CO₂ emission reduction benefits.100%equipment large-scaling contributes to the largest,accounting for 30.05%in total emission reduction in LCS.Application of hydrogen reduction ironmaking technology with a share of 30%results in 19.55%reduction.Replacing 15%of converter steelmaking with electric arc furnace(EAF)technique contributes to 14.74%reduction.The CO₂ emission intensity of blast furnace and base oxygen furnace(BF-BOF)technique is over 2.5 times that of EAF whose application rate is restricted by the recycling amount of scrap steel.By 2030,the CO₂ emissions per ton of steel in LCS will decrease by 5.05%and 11.09%for BF-BOF technique and EAF technique,respectively,compared to the base year.(4)Achieving low carbon development of iron and steel production heavily will rely on the increase in the penetration rate of hydrogen-reduction ironmaking technology and EAF technique,low carbon electricity,and high electrification rate.The LCA-LEAP model constructed in this study is also suitable for conducting studies on energy use and CO₂ emissions in other industries,helping researchers to obtain systematic and refined data on emissions and emission reductions.The research results and findings can provide an important scientific basis for decision makers to formulate low carbon development policies for the iron and steel industry and accelerate the achievement of carbon peaking in the iron and steel industry.