Prospects of green iron- and steelmaking via the FFC Cambridge process

The FFC Cambridge Process promises green iron-/steelmaking, where the respective metal oxides are used as the cathode in a molten electrolyte. Laboratory tests have validated the process at 500–900°C in molten chlorides, carbonates, fluorides or hydroxides. The reduction proceeds mainly through Fe(III)→Fe(II)→Fe(0), with energy consumption as low as 2.8–3.0 kWh/kg and current efficiencies exceeding 90%. With an inert anode and electricity from renewables, the process produces zero or near-zero CO 2 . The electrolysis can also produce, for example, magnetic powders and marine engineering alloys. Particularly, preliminary studies showed potentials of the FFC iron powder as a regenerative fuel (regefuel) for combustion. The combustion-produced iron oxides can be readily recovered and fed back to the process, contributing to a closed-loop fuel cycle. Further improvements are expected for, for example, fuel loading, fluidisation and airflow management, aiming at minimising local heat loss from in-situ sintering and maximising fuel-air mixing for more complete combustion.