Extensive review of the opportunities to use biomass-based fuels in iron and steelmaking processes

Steel production is one of the most energy and carbon intensive industries contributing 5-7% of the global CO2 emissions. In the search for ways to decrease fossil CO2 emissions, biomass-based reducing agents are considered as one promising opportunity. This paper presents the results of a systematic literature review of technological possibilities and constraints, environmental performance and economical limitations of using biomass-based reducing agents in iron and steelmaking processes. The review indicates that biomass-based reducing agents could be applied in the main iron and steelmaking unit processes with varied fossil fuel replacement ratios. The greatest potential to replace fossil fuel is in the charcoal injection to the blast furnace. Life cycle emissions of steelmaking may be considerably lowered through biomass-based reducing agent use. The main constraint in facilitating the transition towards biomass-based steelmaking seems to be the high price of biomass and biomass-based reducing agents compared to fossil-based reducing agents. In the future, there is a need to develop simultaneously cross-industrial production platforms to produce biomass-based reducing agents and other, more valuable products from biomass. This would enhance the economic and environmental performance of producing steel with biomass-based reducing agents.