Kobelco's achievement is said to be the result of the integrated efforts of the business, which operates a construction and quarrying machine subsidiary of the same name, in leveraging its diverse operations. The demonstration test was conducted for a month at a 4,844m³ blast furnace at 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. In the demonstration test, Kobelco says it was verified that RAR could be stably reduced from 518kg/thm (ton hot metal) to 415kg/tHM by charging a large amount of hot briquetted iron (HBI) produced by the MIDREX Process. Kobelco claims the results indicate that this technology can reduce CO₂ emissions by approximately 20% compared to a conventional method.
The MIDREX Process is the leading direct reduced iron (DRI) making process, which produces approximately 80% of the world's direct reduced iron with natural gas (approximately 60% of the world's direct reduced iron at large).
The MIDREX Process uses natural gas as the reductant and pellets made of iron ore as the source of iron to make DRI through the reduction process in the shaft furnace. Compared to the blast furnace method, the MIDREX Process can reduce CO₂ emissions by 20 to 40%. There are over 90 MIDREX modules worldwide.
Kobelco, which also trades as the Kobe Steel Group, also claims the world's lowest coke rate - 239kg/thm - was achieved in its demonstration test. The company sees it as a promising solution that could become readily available shortly at a lower additional cost than other CO₂ reduction measures. Kobelco is considering licensing the technology worldwide.
A company statement said: "We will keep improving this CO2 reduction solution technology while further 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.
"In addition, we believe that the success of the demonstration test on an actual blast furnace has made a significant step forward in providing low CO2 steel products to customers. As moving forward with our environmental efforts on the scale of the whole supply chain, we will establish production and sales systems and define the terms and conditions for sales so that we can provide customers with low CO2 steel products that offer new added value."
Kobelco says it aims to develop and establish technologies that can reduce CO₂ emissions as quickly as possible and at the lowest possible cost to proceed with the initiatives to create a green society toward achieving carbon neutrality in 2050, as declared by the Japanese government.
"Kobelco has always strived to and will continue to provide solutions to the needs of society by making the best use of the talents of our employees and our technologies to realise a world in which people, now and in the future, can fulfil their hopes and dreams while enjoying safe, secure, and prosperous lives."