Gas Injection into Blast Furnace Tuyeres

Injecting gas into blast furnace tuyeres presents a promising method for reducing carbon emissions, especially when using gas with a high hydrogen content. This decarbonization technology reduces emissions without significantly increasing the cost of iron production, making it a low capital expenditure (CAPEX) and high return on investment (ROI) solution.

Various gases containing reducing agents can be injected at the tuyere to reduce carbon emissions in blast furnaces. Some of these gases are by-products of steelmaking processes and can be utilized in the blast furnace to achieve an overall carbon reduction.

Some common gases used for this purpose:

Hydrogen Gas and Synthesis Gas (Syngas) Injection

Injecting hydrogen-rich gas into blast furnace tuyeres is becoming increasingly feasible as synthetically manufactured gases and hydrogen become commercially viable. Pure hydrogen can be purchased directly from the market at this time, and synthetically manufactured gases can be produced through processes like steam reforming, pyrolysis, and gasification. Both hydrogen and syngas help reduce carbon emissions by utilizing a clean hydrogen-bearing gas at the tuyeres.

Coke Oven Gas (COG) Injection

Coke oven gas is typically available at iron and steel production facilities. If there is an excess, it is sensible to use this valuable stream by injecting coke oven gas into blast furnace tuyeres. Coke oven gas offers benefits similar to syngas, with an approximate CO₂ reduction of around 7%. While coke oven gas can present initial challenges, if suitably clean, it can be readily compressed and injected into the blast furnace tuyere.

Alternative Gas Injections

Moreover, alternative gases can be injected into the furnace tuyeres to achieve overall carbon reduction, such as natural gas, coal bed methane, and gases blended with additional hydrogen.

Primetals Technologies recognizes that the pathway to a low-carbon future in ironmaking lies not only in breakthrough technologies but also in optimizing existing processes with innovative approaches. Gas injection at the blast furnace tuyeres—particularly using hydrogen or hydrogen-rich gases offers a practical, scalable, and economically sound solution to reduce carbon emissions.

By harnessing the potential of available resources such as coke oven gas, syngas, and hydrogen, steel producers can take meaningful strides toward sustainability without compromising operational efficiency or profitability. As the industry faces increasing pressure to decarbonize, adopting tuyere gas injection is a critical step toward achieving cleaner, greener steel production.