Green hydrogen can decarbonize steel production primarily by replacing fossil fuels in Direct Reduced Iron (DRI) processes and enabling electric arc furnace (EAF)-based steelmaking. Here’s how:
1. Replacing fossil fuels in DRI production
Traditional DRI uses natural gas-derived syngas (hydrogen + carbon monoxide) to strip oxygen from iron ore, but this emits CO₂. Green hydrogen acts as a zero-emission reducing agent, producing only water vapor as a byproduct.
- Process: Pellets of iron ore are exposed to hydrogen instead of syngas, removing oxygen via Fe2O3 + 3H2 → 2Fe + 3H2O.
- Impact: Eliminates process emissions from reduction and avoids coal/coke use in blast furnaces.
2. Enabling hydrogen-based direct reduction (H-DRI)
H-DRI plants can be paired with renewable-powered electric arc furnaces to melt the reduced iron, fully replacing coal-dependent blast furnaces.
- Scalability: H-DRI with EAFs is closer to commercialization than alternatives like iron electrolysis.
- Infrastructure: Existing DRI-EAF plants (e.g., in the Middle East) are adapting to hydrogen blends, easing transitions.
3. Complementing carbon capture and storage (CCS)
While hydrogen targets process emissions, CCS can address residual CO₂ from auxiliary processes (e.g., power generation). Some projects use hydrogen as a bridge while scaling CCS retrofits.
Key challenges
- Cost: Green hydrogen remains expensive compared to fossil fuels, though costs are falling with electrolyzer advancements.
- Scale: Current hydrogen production capacity is insufficient for global steel demand; large-scale green hydrogen hubs are needed.
Note: While the exact chemical equation isn’t explicitly stated in the sources, the reaction is consistent with the described DRI process using hydrogen.
Original article by NenPower, If reposted, please credit the source: https://nenpower.com/blog/how-can-green-hydrogen-help-decarbonize-the-steel-industry/
