风化壳淋积型稀土矿浸取过程的模拟计算研究Ⅰ:液-固萃取模型  

Simulation on Leaching Process of Weathered Crust Elution-Deposited Rare Earth Minerals:Ⅰ Liquid-Solid Extraction Model

作　　者：程福祥 吴声[1,2] 廖春生 严纯华[2] Cheng Fuxiang;Wu Sheng;Liao Chunsheng;Yan Chunhua(China Minmetals(Bei-jing)Research Institute of RE Co.,Ltd,Beijing 100085,China;College of Chemistry and Molecu-lar Engineering of Peking University,State Key Laboratory of Rare Earth Materials Chemistry and Ap-plications,Beijing National Laboratory for Molecular Sciences,Beijing 100871,China)

机构地区：[1]五矿(北京)稀土研究院有限公司,北京100085 [2]北京大学化学与分子工程学院,稀土材料化学及应用国家重点实验室,北京分子科学中心,北京100871

出　　处：《中国稀土学报》2022年第1期103-112,I0003,共11页Journal of the Chinese Society of Rare Earths

基　　金：国家重点研发计划资助项目(2019YFC0605005)资助。

摘　　要：风化壳淋积型稀土矿物中稀土元素主要富集在以高岭土为主的粘土矿物中,目前主要通过原地浸矿工艺开采。开采过程中,浸矿液自矿体顶部注液孔流至矿体底部或集液巷道的过程中,不断交换浸出粘土中的稀土离子,其过程可视作液-固萃取,因此可通过其中的萃取平衡和物料平衡关系进行模拟计算。介绍了一种基于液-固萃取模型的风化壳淋积型稀土矿柱浸过程模拟计算方法,并探讨了离子交换反应系数、浸矿剂浓度、原矿品位等因素对于浸矿效果的影响。计算表明:铵根离子具有较强的交换浸出稀土的能力;浸出液所能达到的理论浓度峰值主要决定于浸取液中初始硫铵浓度;浸矿所需顶水理论注入量可依据矿体饱和含水率估算,并进而通过模拟计算的浸矿液/顶水比计算所需浸矿液注入量;浸矿液硫铵浓度越高,原矿稀土品位越低,则稀土离子穿透曲线浓度峰值持续时间就越长,之后浓度下降速度也越快,同时浸矿液/顶水比以及硫铵投入/稀土产出比也越小,说明浸矿剂利用效率越高。Rare earth elements(RE)in weathered crust elution-deposited minerals are enriched on clay mineralmainly consisted of kaolinite and extracted popularly by in-situ leaching process at the present time.In the process,NH4+ion in the leaching solution continuously exchange with rare earth ions on clay during flowing down to the bottom of the mine or collection tunnels from injection holes on the top of the mine,which can be considered as a liquid-solid extraction process and therefore simulated accordingly by extraction equilibrium and mass balance.The present article introduced a simulation method of column leaching of weathered crust elution-deposited rare earth minerals on the basis of liquid-solid model,and discussed the influences of reaction constant,leaching agent content,mine grade,etc.on leaching efficiency.The results show that NH4+ion behaves as a strong exchanger to rare earth in the mineral,and its initial content in leaching solution determines the theoretical peak content of RE in resulting leaching liquor;the consumption of water for discharging leaching liquor can be calculated according to saturation water rate inmineral,and then that of leaching solution calculated according to the solution/water ratio obtained from simulation;both the higher content of leaching agent and the lower RE grade of mine will lead to the longer duration of peak content and the steeper drop after the peak in the respective RE leaching curves as well as the smaller ratios of both leaching solution to water and(NH_(4))_(2)SO^(4) input to RE output,and therefore the higher efficiency of leaching agent performance.

关 键 词：风化壳淋积型稀土矿 柱浸 液-固萃取模型 离子交换机制 稀土穿透曲线 

分 类 号：O614.33[理学—无机化学]