Iron ore reduction is a primary unit operation in current metallurgy processes and dominates the energy consumption and greenhouse gas (GHG) emissions of the iron-making process. Therefore, even a slight improvement of the energy efficiency or GHG emissions of iron ore reduction would yield considerable benefits to the cost of pig iron and, more importantly, to mitigation of the associated carbon footprint. The current study presents a discrete model that describes the iron ore reduction process for a single pellet. The transient reaction progress can be predicted and is validated against experimental measurements under various operating conditions, including different reducing gases and temperatures. The effects of pressure, isothermality, gas composition, and flow rate on reduction are investigated. The reduction rate increases significantly with increasing pressure until 5 atm, and the entire reduction process occurs more slowly under non-isothermal conditions than under isothermal conditions. This work provides a solid foundation for the development of a comprehensive particulate system model that considers both heat and mass transfer.

减少铁矿石是当前冶金过程中的主要单元操作，并且在炼铁过程中占能源消耗和温室气体（GHG）排放的主导地位。因此，即使稍微降低铁矿石的能源效率或GHG排放量，也将为生铁的成本，尤其是减轻相关的碳足迹带来可观的收益。当前的研究提出了一个离散模型，该模型描述了单个颗粒的铁矿石还原过程。可以预测瞬态反应进程，并可以在各种操作条件下（包括不同的还原性气体和温度）根据实验测量值对瞬态反应进行验证。研究了压力，等温性，气体组成和流速对还原的影响。还原速率随着压力的增加而显着增加，直到5个大气压，并且整个还原过程在非等温条件下比在等温条件下进行得更慢。这项工作为开发同时考虑传热和传质的综合颗粒系统模型提供了坚实的基础。