The production of biogenic carbon and green hydrogen through biomethane pyrolysis: the environmental benefits for the metallurgy sector

The iron and steel industry is responsible for around 4% of androgenic CO2 emissions in Europe and 9% worldwide. This is due to the massive use of carbon coke in metallurgy, which is not only linked to energy purposes, but also to the chemical process of iron ore refining. The steel sector urgently needs to find alternative solutions to improve en- vironmental sustainability, with the transition to a low-carbon scenario representing a major challenge. The pyrolysis of methane is gaining more and more attention for the production of hydrogen, as this alternative process to hydrogen production does not generate any CO2 emissions, but provides a solid carbon product that can be re-used in an industrial symbio- sis. If biomethane is used, the pathway is even carbon-negative, and generates a net GHG reduction compliant with the EU ETS (Emission Trading Scheme). However, given the high demand for inlet streams in the EU steel sector, the biomethane currently available is not able to meet the entire hydrogen demand assuming that the steel is produced using the DRI-EAF (Direct Reduction Iron- Electric Arc Furnace) route. Only when looking at the European projections for biomethane production in 2050, it is expected that the demand for steel hy- drogen can be totally met, in particular by using 48% of the available biomethane, allowing up to 6 million tons of green hydrogen to be produced, and a significant reduction in net CO2 emissions. Finally, the aim of this work is to assess the energy consumption and environmen- tal benefits resulting from the production of green hydrogen and biogenic carbon in Europe for DRI-EAF, compared to the benchmark market (DRI-EAF fed with natural gas) and the electrolysis alternative.