December 1, 2022
When it comes to low-carbon technology in the iron and steel industry, one has to mention hydrogen direct reduction ironmaking, which is commonly referred to as a type of hydrogen metallurgy, and is one of the recognized paths to realize ultra-low carbon ironmaking. Hydrogen direct reduction ironmaking refers to the process of producing direct reduced iron by reducing solid-phase iron ore (hematite, magnetite, etc.) with hydrogen. The direct reduced iron obtained under this condition contains many micropores, similar to sponge, and is often called "sponge iron". Sponge iron has high activity and is easy to oxidize/combust in the air. In order to reduce the oxidation of sponge iron, usually Sponge iron is pressed into block products to reduce its specific surface area and reactivity.
Since my country's iron and steel smelting technology is mainly based on the blast furnace-converter long process, that is to say, the blast furnace ironmaking process is the main carbon emission unit, accounting for about 74% of the total carbon emissions. Carbon as a reducing agent and heat source produces a large amount of carbon dioxide, so the key to reducing emissions is carbon raw material substitution and process change. Therefore, it is an effective way to develop short-process technology for scrap steel recycling, oxygen-enriched blast furnace, tempering co-production, and waste heat and energy utilization.
