Japan’s Kobe Steel technology can cut blast furnace emission by 20%

18 February 2021

Japan’s Kobe Steel said (16th February) that it has successfully demonstrated technology which can significantly reduce CO2 emissions from blast furnace operations by combining Midrex and the blast furnace operation technology in the iron and steel business. Compared to the blast furnace method, the Midrex Process can reduce CO2 emissions by 20 to 40%, using hydrogen as a reductant.

Kobe was conducting the demonstration test for a month-long using a large blast furnace (4,844 cubic metres) of the Kakogawa Works in Hyogo Prefecture, Japan, in October 2020.

The quantity of CO2 emissions from the blast furnace is determined by the reducing agent rate (RAR) or the quantity of carbon fuel used in blast furnace ironmaking. The demonstration test verified that RAR could be stably reduced from 518 kg/tonnes hot metal to 415 kg/ tonnes hot metal by charging a large amount of hot briquetted iron (HBI) produced by the Midrex Process.

The results indicate that new technology can cut CO2 emissions by nearly 20% compared to a conventional method. In addition, the world’s lowest level of coke rate (239 kg/thm) has been achieved in the demonstration test of this technology.

The Midrex Process uses natural gas as the reductant and pellets made of iron ore as the source of iron to make direct reduced iron through the reduction process in the shaft furnace. Compared with the blast furnace method, the Midrex Process can reduce CO2 emissions by 20-40%.

Concept of CO2 Reduction Solution using hydrogen — Kobe Steel Concept of CO2 Reduction Solution. Source: Kobe Steel

Kobe said: We will keep improving this CO2-reduction solution technology while reducing CO2 emissions and achieving lower costs for CO2 reduction. Beyond our efforts to reduce emissions from our facilities, we will strive to contribute to the acceleration of CO2 reduction by introducing this solution to blast furnaces around the world.

While the natural gas-based Midrex Process, paired with an EAF, has the lowest CO2 emission of any steelmaking route using iron ore. The emission can be further reduced by using hydrogen as a fuel and chemical reactant in the process. The best option is to use green hydrogen to produce DRI as feedstock for steelmaking known as Midrex H2.