含钴废料氯化挥发提钴机理与过程调控

Cobalt is an important strategic metal. The cobalt reserves and production of China account for only 1.1% and about half of the world’s reserves and production, respectively. As the increase of cobalt consumption, there are large amounts of cobalt-bearing wastes produced every year in China, whose cobalt contents are much larger than the China’s mean grade of cobalt ores. Therefore, it is pretty significant for the utilization of cobalt-bearing wastes. The present process could not completely utilize the cobalt-bearing, such as beneficiating method, pyrometallurgy process, hydrometallurgy process and microorganism leaching method. In this study, the chlorination-volatilization process is adopted for the efficient utilization of cobalt-bearing wastes.. There are very few investigations about the chlorination-volatilization of cobalt compounds at present. Focusing on the chlorination-volatilization process development for the recovery of cobalt-bearing wastes, the followings are mainly investigated, including chlorination-volatilization law of cobalt compounds, effect of cobalt occurrence states on their chlorination-volatilization behaviors, gas-liquid-solid coupled reaction kinetic model for the chlorination-volatilization, controllable decomposition of chlorinating agent and ballability of cobalt-bearing wastes. A larger scale tests will be carried out further for the chlorination-volatilization process of cobalt-bearing wastes to solve the synergistic and coupling effects between temperature schedule, pellet property and cobalt chlorination-volatilization rate and to achieve the nearly complete volatilization of cobalt and efficient utilization of cobalt-bearing wastes based on the laboratory experiments. The results of this study could supply the theoretical foundation and technical support for the chlorination-volatilization process development for the recovery of cobalt-bearing wastes, and provide reference for the recovery of other rare and precious metals by chlorination-volatilization process.

钴是重要的战略金属。我国钴储量仅占世界1.1%，而产量占比近半。随着钴消费量的逐年增加，含钴废料大量产生，其钴含量远高于我国钴矿平均品位（0.02%）。因此，含钴废料的回收利用具有重要的意义。现有的选矿法、火法、湿法和微生物浸出法等工艺均不能全量化利用含钴废料。本课题提出了采用氯化挥发工艺全量化和高效利用含钴废料的技术路线。. 钴氯化挥发的相关研究至今几乎空白。围绕含钴废料氯化挥发回收工艺的开发，本课题主要研究钴化合物的氯化挥发规律与赋存形态的影响、气-液-固三相耦合反应动力学模型的构建、氯化剂的可控分解、含钴废料的成球性。在此基础上进行含钴废料氯化挥发工艺的扩大试验，解决温度制度、球团性能和钴氯化挥发率的协同耦合效应，以实现钴近乎全部挥发，含钴废料高效利用。研究成果可为含钴废料氯化挥发回收工艺的开发提供理论指导和技术支撑，并对今后其他稀贵金属的氯化挥发回收提供借鉴。

钴是重要的战略金属。我国钴储量仅占世界1.1%，而产量占比近半。随着钴消费量的逐年增加，含钴废料大量产生，其钴含量远高于我国钴矿平均品位（0.02%）。因此，含钴废料的回收利用具有重要的意义。本课题提出了采用氯化挥发工艺全量化和高效利用含钴废料的技术路线。围绕含钴废料氯化挥发回收工艺的开发，本课题明确了组分、温度、气氛、氯化剂种类、氯化剂添加量和还原剂等因素对钴化合物氯化挥发行为的影响以及钴化合物与固体氯化剂反应时的物相转变规律，揭示了钴赋存形态对其氯化挥发行为的影响，研究了钴化合物氯化挥发的动力学和氯化剂的分解动力学行为，解决了工艺制度、温度制度、球团性能和钴氯化挥发率的协同耦合效应，研究成果为含钴废料氯化挥发回收工艺的开发提供理论指导和技术支撑，并对今后其他稀贵金属的氯化挥发回收提供借鉴。