7TH EUROPEAN COKE AND IRONMAKING CONGRESS - ECIC 2016

Saving energy and reducing CO2 emissions from the steel works are important issues for the steel industry. Because heat loss at the blast furnace is already less than 10% of input energy, saving energy at the blast furnace decreases the energy supply to downstream processes in the steel works. However, it is possible to reduce energy consumption for agglomeration processes such as coking and sintering without reducing the energy supply to downstream if the regulations applied to burden material strength can be relaxed. The inner volume of an oxygen blast furnace can be reduced to half that of a conventional blast furnace with the same production because the productivity of the oxygen process is almost double that of the conventional furnace. As a result, the blast furnace burden load is reduced, and regulations on burden strength can be relaxed. In this paper, the burden load and amount of energy saving of the oxygen blast furnace were evaluated by using the Discrete Element Method and a heat and energy balance model, respectively. Energy supply is also a societal responsibility for steel works, especially after the Great East Japan Earthquake of 2011. Therefore, the energy balance of the oxygen blast furnace under operation as a gasification furnace was also evaluated.