How does gas-based DRI, as used in Monterrey, change a steel mill's CBAM figure?

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Senseible · Accepted Answer

Natural gas reduction emits far less CO2 per tonne of iron than a coal blast furnace, so DRI made with gas carries a low direct figure into the steel. Count the gas burnt in the reformer and shaft as direct emissions of the DRI, then add the EAF's own direct emissions. In a gas-based shaft furnace, natural gas is reformed into hydrogen and carbon monoxide, which strip oxygen from iron ore pellets. The carbon in the gas leaves as CO2 from the reformer stack and process gas. That CO2 is the DRI's direct emissions; the pellets bring their own embedded emissions as a precursor. The EAF adds electrode, charge carbon and burner gas emissions. Electricity for the shaft furnace, compressors and the EAF is not counted for steel under CBAM today, though buyers counting the full footprint will add it. Some gas-based plants capture CO2 from process gas and sell it. Only CO2 that is permanently stored or used in ways the CBAM monitoring rules accept can be deducted; CO2 sold for drinks or other short-lived uses still counts as emitted.

How does gas-based DRI, as used in Monterrey, change a steel mill's CBAM figure?

Where the CO2 comes from

Then the EAF

Captured CO2

Worked example: one tonne of DRI (illustrative inputs)

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