白云鄂博稀土矿浮选降磷的氧化与抑制协同作用  

The Synergistic Effect of Oxidation and Inhibition in Phosphorus Reduction of Bayan Obo Rare Earth Ore with Flotation

作　　者：曹永丹 黄进 柳召刚 常胜[1,2] 高凯 CAO Yong-dan;HUANG Jin;LIU Zhao-gang;CHANG Sheng;GAO Kai(School of Mining and Coal,Inner Mongolia University of Science and Technology,Baotou 014010,China;Key Laboratory of New Technologies of Modern Metallurgy and Application of Rare Earth Materials,Baotou 014010,China;School of Material and Metallurgy,Inner Mongolia University of Science and Technology,Baotou 014010,China;Baotou Research Institute of Rare Earths,Baotou 014030,China)

机构地区：[1]内蒙古科技大学矿业与煤炭学院,内蒙古包头014010 [2]内蒙古自治区稀土现代冶金新技术与应用重点实验室,内蒙古包头014010 [3]内蒙古科技大学材料与冶金学院,内蒙古包头014010 [4]包头稀土研究院,内蒙古包头014030

出　　处：《稀土》2023年第5期1-12,共12页Chinese Rare Earths

基　　金：国家自然科学基金项目(51634005,51764045);内蒙古自治区自然科学基金项目(2016ZD05,2019MS05039)。

摘　　要：现行稀土冶金工业生产所使用的浓硫酸焙烧法要求控制原料(即稀土精矿)铁磷比,目前包钢宝山矿业生产的品位65%稀土精矿中磷的相对含量偏高,需在后续冶金过程中加入以杂质形式除去的铁,增加成本和固废产出量的同时又会对后续萃取流程造成影响,因此需要在选矿过程中就将磷的含量降下来。以白云鄂博选铁尾矿为原料,以模拟选矿回水为选矿用水进行浮选试验,探究回水中杂质对稀土浮选指标的影响,得出稀土精矿中磷含量相对偏高的原因是选矿回水中作为絮凝剂的聚丙烯酰胺(PAM)使含磷矿物上浮。引入以羟基自由基(·OH)为氧化剂的高级氧化法(AOPs)对矿浆中的PAM进行氧化降解处理,减弱其对含磷矿物的活化作用,降低精矿中的磷含量,羟基自由基(·OH)同时可以将稀土矿物表面水解的Ce(Ⅲ)转化为能更容易与捕收剂羟肟酸结合的Ce(Ⅳ),提高精矿稀土品位。以水玻璃+焦磷酸钠作为组合抑制剂,与AOPs协同作用,在有效降低稀土浮选精矿磷含量的同时提高稀土品位,以“一粗三精”的工艺进行开路浮选验证试验,可以得到稀土品位63.30%、稀土回收率54.12%和含磷1.83%的高稀土品位低含磷量的稀土精矿。The concentrated sulfuric acid roasting method used in the current rare earth metallurgical industry needs to control the iron⁃phosphorus ratio of raw materials(i.e.rare earth concentrate).At present,the phosphorus content of the rare earth concentrate with grade of 65%produced by Baoshan Mining of Baotou Steel is relatively high.It is necessary to add iron removed in the form of impurities in the subsequent metallurgical process,which will increase the cost and solid waste output while affecting the subsequent extraction process.Therefore,the phosphorus content needs to be reduced in the beneficiation process.The flotation test was carried out with Bayan Obo iron tailings as raw material and simulated beneficiation backwater as beneficiation water to explore the influence of impurities in backwater on rare earth flotation index.It was concluded that the reason for the relatively high phosphorus content in rare earth concentrate was that polyacrylamide(PAM)as flocculant in the beneficiation backwater makes the phosphate minerals float.The advanced oxidation processes(AOPs)with hydroxyl radical(·OH)as oxidant was introduced to degrade PAM in the pulp,which weakened the activation of phosphorus⁃containing min⁃erals and reduced the phosphorus content in the concentrate.At the same time,hydroxyl radical(·OH)could convert Ce(Ⅲ)hydrolyzed on the surface of rare earth minerals into Ce(Ⅳ)which could be more easily combined with the collector hydroxamic acid,and improve the grade of rare earth concentrate.By using water glass and sodium pyrophosphate as a com⁃bined inhibitor,combined with AOPs,the phosphorus content of rare earth flotation concentrate could be effectively reduced while the rare earth grade can be improved.The verification test of open circuit flotation with“one roughing and three clean⁃ing”process,the rare earth concentrate with high rare earth grade and low phosphorus content was obtained with rare earth grade of 63.30%,rare earth recovery of 54.12%and phosphorus content of 1.83%.

关 键 词：选矿回水 降磷 聚丙烯酰胺(PAM) 高级氧化法(AOPs) 组合抑制剂 

分 类 号：TD955[矿业工程—选矿]