In the mid- to short-term, we plan to reduce carbon emissions by expanding the use of low-carbon fuel and raw materials, operating at a low HMR (Hot Metal Ratio), and introducing EAFS using the current facilities through low-carbon bridge technology. In the long-term, we aim to achieve carbon neutrality by gradually implementing POSCO’s hydrogen reduction ironmaking technology, ‘HyREX (Hydrogen Reduction).’

Pellets are raw materials processed into spherical shapes of a certain size after crushing and screening iron ore. Simply switching the blast furnace raw material from sintered ore to pellets can reduce the fossil fuel used in sintered ore production. HBI (Hot Briquetted Iron) is a raw material that has undergone a reduction process to remove oxygen from iron ore. When HBI is fed into the blast furnace, it reduces the amount of coking coal required for reduction. Generally, using 100kg of HBI per ton of molten iron production reduces CO₂ emissions by 100kg compared to sintered ore. POSCO is planning an HBI production project in iron ore-rich Australia to ensure a stable supply of HBI.

The converter,BOF(Basic Oxygen Furnace) is a large cauldron-shaped facility that holds molten iron produced in a blast furnace. By blowing oxygen into the molten iron, impurities are removed, and refined steel with desired components is produced. Assuming the total carbon emissions for producing one ton of molten steel is 100%, approximately 80% is generated during the production of molten iron. Therefore, converter-based bridge technology aims to reduce the amount of molten iron used in the converter and increase the amount of scrap.

There are mainly two approaches to reduce the amount of molten iron in the converter.

Since 2021, POSCO, in collaboration with the Research Institute of Industrial Science & Technology (RIST), has been conducting a public-private joint national R&D project to demonstrate carbon dioxide capture and conversion technology. This technology separates and captures high-purity CO₂ from high-temperature gases generated in blast furnaces, converters, and FINEX melting furnaces, then injects the CO₂ into the coke oven to be used as a heat source for byproduct gas power generation.
In January 2024, demonstration results at Pohang Steelworks revealed that injecting CO₂ at a medium purity level of 65-70% into the coke oven is economically feasible, as it does not require additional energy for further purification. Additionally, the calorific value of the coke oven gas (COG) increased by approximately 7%. Expanding this application to Pohang and Gwangyang Steelworks is expected to reduce CO₂ emissions by 320,000 tons annually. Furthermore, the commercialization of liquid carbon dioxide production using medium purity CO₂ byproduct gas is underway. This will enable the economic production of liquid carbon dioxide with a purity level of 99.99%, potentially expanding the industrial gas product portfolio and reducing CO₂ emissions by 170,000 tons annually (assuming the production of 200,000 tons of liquid carbon dioxide per unit).

Hydrogen reduction ironmaking is a technology that replaces metallurgical coal used as a reducing agent and heat source in the ironmaking process with hydrogen, drastically reducing GHG emissions. Recognized for its strategic importance to national security and its overall impact on the national economy, hydrogen reduction ironmaking technology was designated as a National Strategic Technology in January 2024.

POSCO’s proprietary hydrogen reduction ironmaking technology, HyREX, is based on the fluidized bed reduction furnace technology of the already commercialized FINEX process. This differs significantly in terms of raw materials and equipment technology from the shaft furnace method used by overseas steel companies.
From a raw material perspective, the shaft furnace uses pellets made by processing iron ore into uniform spherical shapes, but HyREX can use fine ore directly, making raw material procurement easier and production costs more economical. From an equipment technology perspective, HyREX’s fluidized bed reduction furnace technology offers superior temperature control compared to the shaft furnace. Most importantly, POSCO’s FINEX process, based on the fluidized bed reduction furnace, already incorporates hydrogen injection and direct reduced iron (DRI) manufacturing technology, which are key components of hydrogen reduction ironmaking, making it the most advantageous technology for implementing hydrogen reduction ironmaking.

POSCO embarked on obtaining the necessary permits and approvals for the 1.35 million square meter construction site of its hydrogen reduction ironmaking plant at Pohang Steelworks in 2021. In July 2022, POSCO entered into an engineering partnership agreement with Primetals, leveraging their expertise in FINEX facility design, to collaboratively work on the main facilities of the HyREX demonstration plant. In 2023, POSCO introduced a hydrogen fluidized bed reduction experimental furnace with a capacity of 50kg per batch at RIST to validate the hydrogen fluidized bed reduction technology. By April 2024, POSCO had completed and successfully tested a 1-ton per hour electric smelting furnace (ESF) pilot facility at Pohang Steelworks. This achievement laid a solid foundation for the development of core technologies essential to the electric smelting furnace and the commercialization of HyREX technology.
POSCO plans to develop and commercialize the core technology of the hydrogen reduction ironmaking process, the hydrogen fluidized bed reduction furnace, by 2030. By 2050, POSCO aims to gradually transition existing blast furnace facilities to HyREX facilities, achieving carbon neutrality. POSCO is also actively involved in forming technology development partnerships to drive the implementation of carbon neutrality within the global steel industry.
In partnership with the worldsteel and Swedish steel company SSAB, POSCO spearheaded the international Hydrogen Iron and Steel Making Forum (HyIS) from 2021 to 2022. From 2023 onwards, the HyIS forum will expand and evolve into the ‘Breakthrough Technology Conference,’ overseen by the worldsteel. POSCO will continue to accelerate low-carbon technology development in the steel industry through collaboration with global steelmakers, fostering cooperation over competition.