Investigation of High-H2 Reducing Gas Delivery Through Shaft-Level Tuyeres With Computational Fluid Dynamics

Abstract

As both a significant contributor to the steelmaking process and the largest single source of CO2 emissions in integrated steelmaking, the blast furnace is a critical area of focus for decarbonization efforts. Generally, the replacement of coke with injected fuels such as natural gas or syngas has been a key pathway for reducing emissions. These injectants provide higher concentrations of H2 reducing gas, decreasing reliance on CO reactions, but they are limited by their endothermic impacts on flame and reducing gas temperature. One potential method of circumventing these limitations is the use of shaft-level tuyeres for high rates of hot reducing gas delivery, in a similar fashion to the direct-reduced ironmaking process. In this paper, the impacts of such a system are investigated with Computational Fluid Dynamics to predict the reaction rates, coke replacement ratios, and carbon emissions of the blast furnace process under the proposed operating scheme.