Japan: Nippon Steel achieves major emissions reduction breakthrough in blast furnace hydrogen trial

• Steel major records rare feat of 43% drop in emissions
  
  
• Pre-heating H2 unlocks significant emissions reduction potential
  
  

Japan Metal Daily: Japan Steel Corporation has established a basic technology for the development of a hydrogen-reduction steelmaking method using a blast furnace. A small test reactor located in the Kimitsu district of the East Japan Steel Works (Kimitsu City, Chiba Prefecture) succeeded in reducing carbon dioxide (CO2) emissions from the furnace body up to 43% by increasing the heating temperature of hydrogen.

The interim target of a 40% reduction, which was set for 2025, was exceeded by one year ahead of schedule. This is the world's highest CO2 emissions reduction rate from a blast furnace that uses hydrogen.

This development test was conducted in November-December as part of the Super Course 50 programme to develop hydrogen reduction steelmaking technology using the government's Green Innovation (GI) fund. JFE Steel and Kobe Steel are also participating. Kimitsu's tests are mainly handled by Nippon Steel.

Hydrogen pre-heating

Hydrogen is accompanied by an endothermic reaction when reducing iron ore, which causes a decrease in furnace temperature, so there is a limit to the amount of blowing. The test reactor with an internal volume of 12 cubic metres was used to verify whether it was possible to supplement the thermal energy by heating and blowing hydrogen in advance.

In this test, in addition to heating the hydrogen itself, the amount of heat input was improved by raising the temperature of the air blowing into the furnace at the same time as hydrogen. By improving the heat balance in the furnace, we succeeded in increasing the reduction effect by 10 percentage points from the previous 33%.

The actual value of 43% achieved by Nippon Steel is much higher than the similar actual value disclosed by domestic and foreign steelmakers.

According to Nippon Steel, the overseas reduction rate is up to 30%. This result shows an emissions reduction rate of more than 10 percentage points. The Super Course 50 programme aims to eventually reduce CO2 emissions from large blast furnaces by 50%.

Future ready

In the future, Nippon Steel will move to the next stage where it is aiming to reduce emissions by 50% while incorporating other low-carbon technologies.

The company is planning to proceed with a demonstration of an actual machine using hydrogen-based gas generated in the steel mill at Nippon Steel's Kimitsu No. 2 blast furnace with an internal volume of 4,500 cubic metres.

Note: This article has been written in accordance with a content exchange agreement between Japan Metal Daily and BigMint.