Analysis of factors influencing CO_2 emissions in an integrated steel works based on Life Cycle Analysis (LCA)

The amount of CO2 emission in steel works occupies a great share of the total industry CO2 emissions in China.Reducing CO2 emission in steel works is urgent for energy saving,environmental protection and sustainable development.This study aims at identifying the main factors resulting in CO2 emissions in steel works and proposing countermeasures based on the study of the life cycle inventory (LCI) of iron and steel products.A certain integrated steel works is taken as an example of LCI analysis by use of the Tornado Chart Tool.Through computations and analyses,it is found that the Electric Furnace Route has less environmental impact than that of the Basic Oxygen Furnace (BOF) Route.The top important CO2 emission factors of the factory are CO2 emission factor of Blast Furnace Gas (BFG),liquid steel consumption coefficient of continuous casting,continuous casting slab consumption coefficient of hot rolling and hot metal ratio of steelmaking.Corresponding effective measures for CO2 emission reduction such as removing CO2 contained in BFG,decreasing the hot metal ratio of BOF,recycling BFG,and optimizing the product structure are thus proposed.