Hydrogen plasma reduction of iron oxides

Hydrogen plasma reduction (HPR) is a novel and facile metallurgical technology which has been receiving increasing attention. It can be applied for green ironmaking by reducing iron ore with significantly less energy consumption and carbon emissions using highly active hydrogen species resulting from the excitation of hydrogen gas. This study reviewed the hydrogen plasma generation mechanisms and reduction reaction features, as well as its applications to reduction of iron oxides. Considering the challenges confronted by current HPR process regarding energy input, equipment stability, thermal control, and cost effectiveness, promising technological solutions were discussed. Among them, the microwave hydrogen plasma reduction (MHPR) technology is expected to offer a new path for ironmaking owing to its long plasma torch lifetime, high reduction rate, good process controllability, and great environmental friendliness.