Fig. 2: Hydrogen uptake during hydrogen-based ironmaking processes.
a Hydrogen desorption spectra of the HyDR, HyDR+melt, and HPSR samples measured by hot extraction tests with a constant ramping rate of 1000 °C/h. b Average hydrogen content (solid square) from measurements obtained for three constant ramping rates of 800, 1000, and 1200 °C/h. These values are denoted as ‘Ramping’. The corresponding error bars represent the standard deviation from the three measurements. The figure shows for reference also the hydrogen content measured by rapid heating to 800 °C at a heating rate of ~800 °C/min (open circle), followed by isothermal holding for 15 min. This value is denoted as ‘Rapid’. c Comparison of the hydrogen contents along the conventional metallurgical (BF stands for blast furnace, BOF for basic oxygen furnace, EAF for electric arc furnace, VAD for vacuum arc degassing) and hydrogen-based metallurgical processes. The corresponding error bars represent the standard deviation from data reported in the literature studies and measurements in the present study. d Deconvolution of hydrogen desorption spectrum of the HyDR product. e. Kissinger plots for the four deconvoluted peaks at ramping rates of 800, 1000, and 1200 °C/h, where Tp stands for the peak temperature of the deconvoluted peaks and Φ for the ramping rate. Details for the Kissinger method are in the Supplementary Method section. f Hydrogen contents corresponding to the four deconvoluted peaks.
