The blast furnace (BF) remains the predominant technology for reducing iron ore today and is expected to be a key component of the global steel industry for years to come.
Modern BFs operate near theoretical efficiency limits but continue to be refined, and many innovative practices are being developed to significantly reduce their carbon footprint.
Innovative practices for reducing CO2 emissions:
Description of practices:
1. Top gas recycling:
Capturing waste CO2 from the blast furnace top gas, converting it into a synthetic gas (syngas) and reinjecting it.
2. Lower-carbon circular reductants:
Replacing fossil coal and coke with biocarbon, hydrogen, and other circular carbon sources.
3. Direct and indirect use of hydrogen:
Hydrogen from internal or external sources can be directly injected, thereby reducing coke rate or combined with BF gas in a methanation process for reinjection.
4. Electrification:
Electricity can further support processes such as hot blast generation and heating, as well as auxiliary systems, reducing reliance on fossil-derived energy.
5. Plasma injection:
The use of plasma torches to heat the hot blast air, and sometimes in conjunction with hydrogen and other auxiliary fuels.
6. Oxyfuel injection:
Injecting natural gas, PCI, or hydrogen with nearly pure oxygen facilitates easier CO2 capture. Often used in conjunction with CCS and top gas recycling.
7. Digitalisation:
Advanced control systems using AI and data analytics optimise performance, enable predictive maintenance, and support real-time emissions monitoring.
8. Carbon capture and storage / carbon capture, storage, and use
Carbon can be captured for use in various industrial processes and stored deep underground in geological formations, thereby reducing its emission intensity. For more information, please visit this page.