Increasing the share of hydrogen in reduction of iron oxide in the blast furnace iron making will directly reduce the share of blast furnace greenhouse gas emissions. In the present study, injection of H₂-rich biomass and plastic materials was studied in terms of its devolatilization, gasification and combustion characteristics. The released gases were identified using mass spectroscopy attached to a thermogravimetric analyzer and the corresponding kinetics parameters were estimated.

The devolatilization was found to occur through two or more steps. The first step is always associated with the release of CO₂, CO, H₂, H₂O and hydrocarbons while only CO and H₂ were detected during the later steps. Combustion and gasification starting temperatures of char of H₂-rich carbonaceous materials were lower than that of pulverized coal char by ≥ 100 °C. The estimated activation energies suggested that, under the present conditions, devolatilization, gasification and combustion were chemically controlled. Carbon reactivity of the char of the studied H₂-rich carbonaceous materials were higher than that of pulverized coal. Moreover, increased H₂–H₂O content in the blast furnace gas, due to injected H₂-rich carbonaceous materials, was found to improve the iron ore pellets reduction kinetics.