基于低温还原氮化-低温选择性氯化的钒铬渣高效分离新工艺基础研究

钒铬渣钒和铬的高效分离已经成为影响我国钒清洁生产的难题，更是严重制约大宗高铬型钒钛磁铁矿综合利用的瓶颈问题。目前针对钒铬高效分离问题所提出的各种基于常规焙烧—浸出工艺似乎都难以实现经济、高效和清洁。因此，独辟蹊径，系统地提出一套革命性的工艺将对解决上述问题具有积极意义。申请人提出了低温氮化—低温选择性氯化处理钒铬渣的新工艺，即通过氮化和氯化耦合达到金属分离的多级选择性，同时实现铁、铬、钒、钛回收与尾渣的无害化。项目通过研究将阐明工艺参数及物相组成对钒铬渣还原氮化的影响规律与调控方法，掌握还原氮化与磨选工艺对氮化渣物相解离的影响规律及分选率提升手段；探明氮化渣低温氯化行为与选择性氯化机制，氯化物中TiCl4与VOCl3的分离方法；明确氯化尾渣中铬回收的影响规律和调控方法，实现尾渣的无害化排放。最终为钒铬渣的高效分离提供解决方案，更为大规模的利用高铬型钒钛磁铁矿资源提供方向。

The efficient separation of vanadium and chromium from vanadium-chromium slag has become a difficult problem affecting the clean production of vanadium in China. The most serious is that it restricts the comprehensive utilization of high-chromium vanadium-titanium magnetite. At present, all kinds of methods proposed basing on the conventional raosting-acid leaching process seem to be difficult to achieve the economic, efficient, and clean separation of vanadium and chromium. Therefore, a revolutionary and systematic process was needed in order to solve the above problems. In this project, a low temperature nitridation and low temperature selective chlorination method was proposed to deal with the vanadium-chromium slag. The recovery of iron, chromium, and titanium can be achieved at the same time based on the multistage selectivity of metal separation of the coupling of nitridation and chlorination. The research will illustrate the influence of process parameters and phase composition on the reduction and nitridation behavior of vanadium-chromium slag, the influence of reduction-nitridation and grinding process on the phase liberation of nitride slag and methods to promote the separation efficiency, the influence law and control method of chromium recovery from chlorinated slag, the separation method of TiCl4 and VOCl3 in chloride, influence and control method of chromium recovery in chlorinated tailings, and the harmless discharge of tailings. This research can provide a solution for the efficient separation of vanadium-chromium slag, and provides a more large-scale utilization of high-chromium vanadium-tianium magnetite resources.