The CO2 reduction potential for the oxygen blast furnace with CO2 capture and storage under hydrogen-enriched conditions

Abstract

The CO2 emission reduction of blast furnace (BF) is critical to the clean and sustainable development of the steel industry. Herein, we studied the CO2 emission reduction potential of oxygen blast furnace (OBF) and oxygen blast furnace under hydrogen-enriched conditions (OBFh-ec) with CO2 capture and storage, via establishing mathematical models, including the stack and bosh model, the combustion zone model, and the gas recycling system model. The in-furnace status, mass and energy consumption, and the CO2 emission of the OBF under four typical conditions were analyzed based on the models. Considering the relationship between BF and upstream and downstream processes, the CO2 emission that BF processes should bear in an integrated steel mill was calculated. The results indicated that, compared with the conventional BF, the CO2 emissions of OBFh-ec decreased by 9-14%, and decreased by 38-44% when the CO2 storage technology was used. Importantly, the hydrogen-enriched injection will affect the carbon emission reduction effect of CO2 capture and storage. The fuel consumption and the comprehensive energy consumption of OBFh-ec decreased. The mechanism in the CO2 emission reduction of OBFh-ec was interpreted based on analyzing the chemical reactions, temperature, and mass flow in the furnace. This study has important implications for understanding the CO2 reduction potential of the OBF using CO2 capture and storage with hydrogenous fuel injections.