Abstract The reaction mechanism models of dechlorination and [Zn] reclaiming in the roasting steelmaking zincrich dust process are studied. The dust collected from a steelwork contains 63.8% zinc and 3.18% chlorine (mass percent), of which, almost all zinc elements exist in ZnO and ZnCl2 forms, and all the chlorine elements are stored in ZnCl2. When the dust is roasted at above 732∘C in an air atmosphere, the ZnCl2 in the steelmaking zinc-rich dust is volatilized into steam and then oxidized into ZnO. Finding the position where the chemical reaction occurs is the key to determining the reaction mechanisms of dechlorination and [Zn] reclaiming. In this study, two groups of thermal experiments are designed and executed for roasting in different atmosphere environments and at different roasting temperatures. Based on the experiment results, the mechanism model is discussed and built, and the reaction of dechlorination and [Zn] reclaiming is shown to be a multi-step process. Because O2 from the air cannot transmit into the dust particle interior or dust bed effectively, the chemical reaction of [Zn] reclaiming occurs in the external gas environment outside of the dust, where the [Zn] recalcining reaction should be limited by the dynamics of new nucleation of ZnO solids.

中文翻译：

---

焙烧炼钢富锌粉尘工艺脱氯与[Zn]回收反应机理模型的实验验证

摘要 研究了焙烧炼钢富锌粉尘过程中脱氯和[Zn]回收的反应机理模型。从钢厂收集的粉尘含有63.8%的锌和3.18%的氯（质量百分比），其中几乎所有的锌元素都以ZnO和ZnCl2的形式存在，所有的氯元素都储存在ZnCl2中。当粉尘在空气气氛中在732∘C以上焙烧时，炼钢富锌粉尘中的ZnCl2挥发成蒸汽，然后氧化成ZnO。寻找化学反应发生的位置是确定脱氯和[Zn]回收反应机理的关键。在这项研究中，设计并执行了两组热实验，用于在不同的气氛环境和不同的烘烤温度下进行烘烤。根据实验结果，讨论并建立了机理模型，表明脱氯和[Zn]回收反应是一个多步骤的过程。由于空气中的 O2 不能有效传递到粉尘颗粒内部或粉尘床，[Zn] 回收的化学反应发生在粉尘外部的外部气体环境中，其中 [Zn] 再煅烧反应应受到动力学的限制。 ZnO 固体的新成核。