The encyclopedia · Engineering & Operations · Technical decision · 2022–2030
POSCO bets steel on HyREX — hydrogen-reduced iron instead of coke in blast furnaces
POSCO's HyREX makes steel with 100% hydrogen in fluidized-bed reactors, cutting CO2 per ton from 2.05t to 0.4t and reusing its FINEX know-how.
POSCO
The solution
Steel is made by stripping oxygen from iron ore, and the world's standard way — coke in a blast furnace — releases large amounts of CO2: about 2.05 tonnes per tonne of molten iron. With carbon neutrality on the horizon, POSCO decided the blast furnace itself had to go.
POSCO's answer, HyREX, marries four fluidized reduction reactors with an electric smelting furnace: powdered ore is reduced directly by 100% hydrogen into direct reduced iron, then melted electrically. It builds on FINEX — the fluidized-bed process POSCO commercialized first in the world in 2007 — and skips the pelletizing that rival shaft-furnace routes require, so lower-grade ore still works.
POSCO says green-hydrogen HyREX cuts CO2 to about 0.4 tonnes per tonne of steel, a fivefold reduction, at roughly 30% higher production cost than coal-based routes today. A 300,000-tonne demo plant is planned from 2027, with commercial technology targeted for 2030 and blast furnaces replaced by 2050.
Why it worked
- Reuses proven FINEX fluidized-bed technology
- Skips pelletizing, allowing lower-grade ore
- Fivefold CO2 cut from the core process
- Cost gap is large but expected to narrow
What can be applied
When regulation threatens the core process, reuse your own earlier invention: HyREX builds on POSCO's FINEX fluidized-bed technology, so competitors climb a paid-for learning curve.
Aftermath
POSCO named HyREX the 'new national treasure No.1' and in 2022 began demo-plant design with Primetals; in 2024 it unveiled the first ESF test furnace, which drew its first molten iron in April. Commercialization is targeted by 2030, with the entire blast-furnace fleet to be replaced by 2050.
Sources
spotted an error? The archive wants to know.