Bio-PCI a renewable reductant for blast furnaces: CO₂ mitigation potential and economical assessment

The steel industry is under pressure to reduce its CO₂ emissions, which arise from the use of fossil coal. In the long-term, the injection of pulverized particles of charcoal from biomass (biochar) through the BF tuyerees, here called Bio-PCI (Bio-Pulverized Carbon Injection), offers attractive features from the environmental and metallurgical viewpoints. Biochar presents advantages based on its carbon-neutrally and on its imparting fewer impurities to the iron than coke. The potential of Bio-PCI, has been assessed from its CO₂ abatement potential and economic point of view. A cost objective function has been used to measure the impact on iron production of biochar substitution in highly fuel efficient BF among the top 9 hot metal producers; estimations are based on cost determinants in ironmaking. This contribution aims to shed light on two strategic questions: under which conditions can be economically attractive to implement Bio-PCI? And where is such a techno-economic innovation likely to be taken up earliest? Results indicate a potential CO₂ mitigation of 18% - 40% with respect current emission rates; on the economic assessment findings show that biochar cannot solely on price compete with fossil coal, thus lower biochar cost or the introduction of carbon taxes are necessary to increment the competitiveness of Bio-PCI. Based on actual prices of raw materials, electricity and carbon taxes, biochar should be between 130.1-236.4 USD/t and carbon taxes 47.1-198.7 USD/t CO₂ to facilitate Bio-PCI substitution in examined countries. With respect to the implementation, Brazil, followed by India, China and USA appeared to be in better position to deploy Bio-PCI.