Volume 61

Estimating Material and Energy Demands of a Transition to Hydrogen-Based Steelmaking Using Mathematical Optimization Carl Haikarainen, Yandong Zhai, Marwa Mortadi, Henrik Saxén

Abstract

One potential alternative for reducing CO2 emissions from the steel industry involves replacing the traditional coal-based steelmaking route with hydrogen-based steelmaking technologies. From a chemical and energetic point of view, this would mean replacing coal as source of energy and carbon for the iron ore reduction process with hydrogen as reductant and electricity as the main energy input. As a highly energy-intensive industry, the sourcing of energy for its needs greatly affects its overall environmental impacts and its role in a wider energy system. This paper evaluates a possible evolution of energy and material demands in different development stages of a steel plant transitioning towards hydrogen-based steelmaking technologies using a long-term mathematical optimization model. Moving to iron ore reduction by hydrogen from electrolysis with electricity from wind turbines would shift the raw material requirements from large amounts of mined coking coal to smaller amounts of diverse materials for the wind turbines and electrolyzers, including rare earth elements, as well as an increased need for natural gas and recycled steel scrap. While the total quantity of required materials will inarguably be reduced, the impacts of construction of and reliance on increased electricity generation will need to be considered.

Keywords steel production, hydrogen, integrated systems, decarbonization, optimization