Decarbonizing Hard-to-Abate Industry

Abstract

Heavy industry — steel, cement, chemicals, and refining — accounts for roughly a quarter to a third of global CO₂ emissions, and its high process temperatures and reaction chemistry (calcination, ore reduction) resist simple electrification or fuel-switching. This paper surveys four decarbonization pathways from a process-engineering standpoint: hydrogen-based direct reduction and combustion, direct electrification of low- and medium-temperature process heat, carbon capture, utilization and storage (CCUS), and clinker substitution or CO₂ mineralization in cement manufacture. Current technoeconomic benchmarks are compiled for each pathway, including green hydrogen and H₂-DRI-EAF steel cost trajectories, heat pump abatement-cost ranges, capture-route selection criteria, and supplementary cementitious material (SCM) substitution limits, with India-specific policy context under the National Green Hydrogen Mission. A six-point screening framework is proposed to sequence efficiency, electrification, hydrogen, materials substitution, and CCUS investment for a given plant or process line.