The iron species in the lower valence state in steel slag are capable of thermochemical H₂O splitting and producing hydrogen energy. The defining of the slag reactivity with varying particle size distributions was put forward. The results showed the hydrogen generation rate was primarily dependent on temperature and particle size. The kinetics analysis revealed a typical self-retardation reaction behavior for the fine slag, due to the clogging of macropores upon oxidation. In comparison, the reaction kinetics of the coarser slag were described well by three-dimension diffusion model and exhibited better resistance against the rate decline. The coarser slag had much more grain junctions and fewer fraction of RO phases distributed at the particle surface. Due to the lack of free surfaces, the volume expansion derived from the oxidation of RO phase would cause larger mismatch stresses at grain boundaries, and further trigger the cracks formation.

钢渣中低价态的铁物种具有热化学能H ₂O分裂并产生氢能。提出了不同粒度分布下炉渣反应性的定义。结果表明，氢气的产生速率主要取决于温度和粒径。动力学分析揭示了细渣的典型的自延迟反应行为，这是由于氧化时大孔的堵塞。相比之下，用三维扩散模型很好地描述了粗渣的反应动力学，并表现出更好的抵抗速率下降的能力。较粗的矿渣具有更多的晶粒结点，并且在颗粒表面分布的反渗透相的分数更少。由于缺少自由表面，由RO相氧化引起的体积膨胀会在晶界处引起更大的失配应力，