Carbon carrier modeled for CO2 emission assessment in steel industry

Abstract

Detailed carbon identification of steel industry is fundamental for CO₂ management and future sustainable production. Herein, Carbon carrier characterized by carbon tracing and assignment is established to identify carbon flow in complexed energy-mass net of steel manufacturing. For traditional iron & steel process, the emission intensity is ∼2.33 t CO₂/t steel if steel is the only product. While considering other by-products and their carbon assignment, the emission intensity would be decreased to ∼1.11 t CO₂/t steel, with the rest assigned to Linz-Donawitz Gas ∼0.30 t CO₂/t steel, Blast Furnace Gas ∼0.84 t CO₂/t steel, and Coke Oven Gas ∼0.08 t CO₂/t steel. Comprehensive utilization of energy and mass is helpful to reduce CO₂ intensity of each product. Waste heat recovery and equipment efficiency improvement of the traditional process can reduce ∼16 % and ∼15 % CO₂, respectively. Steel-making by Electric Arc Furnace achieves 90 % CO₂ cut-down. With application of Carbon carrier, industry carbon management can be conducted to accelerate future decarbonization.