Direct reduction of mixed biomass-Fe2O3 briquettes using biomass-generated syngas

This paper presents a novel ironmaking technology using biomass and iron oxide. The biomass instead of coke was mixed together with iron ore powder, water, limestone and bentonite for the production of Fe2O3 briquettes. The sintering process and direct reduction of briquettes were simultaneously conducted in the same reactor. Briquettes with different composition were isothermally reduced directly to metallic iron with H2–CO mixtures at different temperatures (ranging from 900 to 1100 °C) and reaction time (30–60 min) to investigate the effects of briquettes composition, reduction temperature, reaction time and reducing gas composition on the quality of metallic iron. The results show that the increase of reduction temperature, reaction time and H2 content of the reducing gas are favorable for the quality of pig iron, within the experimental conditions. At a reduction temperature of 1100 °C and reaction time of 60 min, the Fe content in product achieves the maximum 94.7%.

► The biomass powder instead of coke was mixed together with iron ore powder, water, limestone and bentonite for the production of Fe2O3 briquettes.
► The sintering process and ironmaking process were simultaneously conducted in the same reactor.
► The syngas produced by biomass steam catalytic gasification was selected as reducing gas.
► Dehydration of combined water and pyrolysis of biomass make the briquette porous, increasing contacting area of iron oxide and reducing gas.