Abstract
Direct reduced ironmaking (DRI) processes are gaining popularity as the preferred technologies to reduce blast furnace related greenhouse gas emissions. Mass and energy balances were developed in Metsim™ modeling software to demonstrate the transition of the well-known Midrex™ and Energiron™ ZR processes from natural gas to hydrogen. Each process was modeled using high Fe containing DR grade iron ore pellets as well as blast furnace grade iron ore (lumps and pellets) for both natural gas and hydrogen operations. Total energy consumption and related greenhouse gas emissions were calculated for natural gas, hydrogen, and mixed fuel operations to illustrate pathways to reduce ironmaking greenhouse gas emissions. Implications of the fuel type on the gas handling train will also be discussed.