A comprehensive literature review of biomass characterisation and application for iron and steelmaking processes

This study provides a fundamental literature review of biomass characterisation and application for utilisation as a reducing agent and fuel in an integrated steelmaking process. This review contains and evaluates the existing literature concerning the properties of different biomass sources and available pre-treatment technologies for upgrading biomasses to have similar characteristics to fossil coal. The suitability of biofuels in different operating units including Brazilian mini blast furnaces, cokemaking, larger blast furnace injection, sintering and production of carbon composite agglomerates are analysed. There is a considerable opportunity to reduce CO₂ emissions in the integrated steelmaking process by using biomass-based reducing agents. The literature reports that charcoal optimisation in the integrated steel plant can achieve reduction in net CO₂ emissions of 31–57%, depending on the substitution rate. Although, some level of pre-treatment is also necessary for efficient use of biomass, the pre-treatment requirement will depend on the unit operation where the biomass material is added. Solid biofuels are considered the most suitable form of biomass-based reducing agents due to similarities in the physical properties with the injected coals; this will make coal replacement more straightforward and lower the costs required for plant modifications.