The utilization of ultrafast air-cooling has been proposed to reduce energy consumption in hydrogen-based mineral phase transformation (HMPT) technology for more sustainable iron recovery. Optimal conditions, including a grinding fineness of −74 μm accounting for 90 wt%, a reducing gas concentration of 20 vol%, a roasting temperature of 540 °C, and an air-cooling temperature of 300 °C, yielded an iron concentrate with a TFe grade of 59.29 wt% and a recovery of 89.40 wt%. The beneficiation indexes obtained by ultrafast air-cooling were comparable to those of the N-cooling method. The reaction mechanisms were comprehensively studied to optimize the process, which revealed controlled oxidation of artificial magnetite to maghemite and hematite under ultrafast air-cooling conditions. The heat released during oxidation was recycled, leading to reduced energy consumption. Furthermore, ultrafast air-cooling increased particle porosity and cracks, thereby reducing subsequent grinding energy requirements. This research advances carbon reduction efforts in the steel industry, facilitating the transition to carbon neutrality.

中文翻译：

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使用超快空气冷却进行热回收，通过氢基矿物相变回收绿色铁：中试规模研究

有人建议利用超快空气冷却来降低氢基矿物相变（HMPT）技术的能耗，从而实现更可持续的铁回收。最佳工艺条件为磨矿细度为-74 μm，占90 wt%，还原性气体浓度为20 vol%，焙烧温度为540 ℃，空冷温度为300 ℃，得到的铁精矿为TFe 品位为 59.29 wt%，回收率为 89.40 wt%。超快空冷法的选矿指标与氮气冷却法相当。全面研究反应机理以优化工艺，揭示了超快空气冷却条件下人造磁铁矿向磁赤铁矿和赤铁矿的受控氧化。氧化过程中释放的热量被回收，从而减少了能源消耗。此外，超快空气冷却增加了颗粒孔隙率和裂纹，从而减少了后续研磨能量需求。这项研究推进了钢铁行业的碳减排工作，促进向碳中和的过渡。