The Study On The Synergies Between Air Pollution And Carbon Emissions Control For Iron And Steel Industry In The Typical City In Hebei Province

China is a major steel producer in the world.Hebei province is the main steel producer in China.A typical city is the main gathering place of iron and steel enterprises in Hebei Province.The iron and steel industry is a typical long process industry with high energy consumption and high pollution,which has a great impact on the environment.Superimposed on the current low-carbon strategic demand of"carbon peak and carbon emission reduction",the energy saving and carbon reduction of the iron and steel industry is the general trend.In this paper,combined with the idea of life cycle management,the emission levels of air pollutants and carbon dioxide in the steel industry of typical cities were studied.Based on a series of standards,an inventory of air pollutants and carbon dioxide emissions in the steel industry of typical cities in 2019 was prepared.Based on the inventory,major iron and steel enterprises were classified and graded.Direct and indirect pollutant emission levels of typical steel production processes were studied.Finally,the long-term Energy Alternatives Planning System model is used to predict and analyze the emission reduction potential of air pollutants and carbon dioxide in the steel industry under different emission reduction control scenarios.The results of the study show that:（1）From 2012 to 2019,despite a 68.9%increase in crude steel production in a typical city,the total emissions of SO₂,NOx and PM_2.5decreased by 69.10%,39.24%and 69.95%,respectively,with significant results in controlling air pollutant emissions from the steel industry.（2）Among the three typical production processes,the total emission intensity of SO₂,NOx,PM_2.5and CO₂decreased by 9.6%～30.6%,in the blast furnace-recycled steel-electric furnace mixed production process because of the use of partially recovered scrap,compared with the blast-converter long process.The total emission intensity of SO₂,NOx,PM_2.5and CO₂in recycled steel-electric furnace process was reduced by64.1%～84.6%,compared with that in blast-converter long process.（3）By 2035,the synergistic emission reduction effect of output control is the most significant（38.8%）,the popularization of energy-saving technology（7.10%～14.77%）.The pollutant emission reduction is 10.40%～37.83%in the end treatment progress without considering carbon capture technology,and CO₂emission is not reduced.（4）Under the combination of electric furnace and energy-saving technology popularization,the reduction ratio of NO_xand CO₂is 18.23%and 15.76%,respectively.In the comprehensive scenario,the emission reduction ratio is 44.36%～73.15%.The emission reduction of NOx and CO₂by electric furnace+energy saving+end-of-pipe treatment can reach 147.66%and 36.5%of the emission reduction by output control respectively.NOx treatment can be achieved by other means without strict control of output,but CO₂emission reduction still needs to be controlled by output.Based on the above conclusions,it is suggested that strengthening the control of steel output and promoting energy saving technology are the main ways to realize the coordinated control of pollution reduction and carbon reduction in typical urban steel industry.It is necessary to accelerate the transformation of ultra-low emission of blast furnace and steel rolling process in enterprises.At the same time,the supply of clean electricity should be increased to reduce the increase of pollutant emissions in the power sector caused by the promotion of electric furnace steelmaking;The emission standards of volatile organic compounds and carbon dioxide in the steel industry should be improved as soon as possible in order to promote the reduction of both types of pollution in the long term.