Niobium (Nb), rare earth elements (REEs), and titanium (Ti) in Bayan Obo tailings are dispersed across various fine mineral phases. To efficiently recover these valuable elements from Bayan Obo tailings, a novel processing method of complex multimetallic-associated ores, utilizing smelting reduction and crystallization control, is proposed and investigated in this study. First, by observing the crystallization behaviors of CaO-SiO-LaO-NbO-TiO slag, we observed that Nb and La (lanthanum) were easily dissolved in the perovskite phase that was selected as the target phase for mineral phase reconstruction due to its good flotation characteristics. The effects of (CaO)/(SiO) and the temperature control profile on the crystallization behaviors are discussed in detail. Based on the above investigation, a mineral phase reconstruction experiment performed on Bayan Obo tailings using smelting reduction and crystallization control was carried out. The results indicated that after carbothermic smelting reduction at 1,600 °C, the iron oxides in the tailings were selectively reduced to molten iron that could settle separately from the molten slag, while Nb, REEs, and Ti were enriched in the slag. After temperature-controlled crystallization of the molten slag, 94 % of the Nb and 63 % of the REEs precipitated in the perovskite, and this created a good mineral phase for the efficient flotation of Nb, REEs, and Ti. Finally, a novel processing method for Bayan Obo tailings is proposed after a feasibility analysis of reactor selection, product value, energy consumption, and eco-friendliness.

中文翻译：

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含铌稀土钛熔渣熔融还原及结晶控制重构白云鄂博尾矿矿相


白云鄂博尾矿中的铌 (Nb)、稀土元素 (REE) 和钛 (Ti) 分散在各种细粒矿物相中。为了有效地从白云鄂博尾矿中回收这些有价值的元素，本研究提出并研究了一种利用熔炼还原和结晶控制的复杂多金属伴生矿的新型加工方法。首先，通过观察CaO-SiO-LaO-NbO-TiO渣的结晶行为，我们观察到Nb和La（镧）很容易溶解在钙钛矿相中，钙钛矿相由于其良好的性质而被选为矿物相重构的目标相。浮选特性。详细讨论了 (CaO)/(SiO) 和温度控制曲线对结晶行为的影响。在此基础上，对白云鄂博尾矿进行了熔融还原和结晶控制的矿相重构实验。结果表明，经过1600℃碳热熔炼还原后，尾矿中的铁氧化物被选择性还原为铁水，并与熔渣分离沉降，而Nb、REE和Ti则富集在熔渣中。熔渣控温结晶后，94%的铌和63%的稀土元素在钙钛矿中沉淀，这为铌、稀土元素和钛的有效浮选创造了良好的矿相。最后，通过对反应器选型、产品价值、能耗和生态友好性的可行性分析，提出了一种新的白云鄂博尾矿处理方法。