A steel mill asks our Liaoning magnesia refractory plant for carbon data. What counts?
Count CO2 from calcining magnesite, about 1.09 tonnes per tonne of magnesia from chemistry alone, plus kiln fuel and electricity. Refractories are not CBAM goods, so this is a Scope 3 figure for the buyer. Give it per tonne of brick or mix shipped.
Process CO2
Calcining magnesium carbonate releases its carbon. Per tonne of pure MgO, the chemistry gives about 1.09 tonnes of CO2; correct for the ore's actual purity.
Energy
- Coal, gas or petcoke in shaft and rotary kilns.
- Fuel for dead-burning or fusing.
- Electricity, including electric arc fusing for fused magnesia.
For the buyer
Refractories are outside CBAM, so the steel mill uses your figure for its own footprint. Give it per tonne of product with the purity and fuel assumptions stated.
What Senseible does here
Senseible reads bills, fuel invoices and production records into dated, fingerprinted records, so the figure you send a buyer can be traced to its documents.
Sources: IPCC 2006 Guidelines for National Greenhouse Gas Inventories, GHG Protocol Corporate Value Chain (Scope 3) Standard, CBAM Regulation (EU) 2023/956, consolidated
Last reviewed 2026-10-22.