摘要
包头混合型稀土精矿通常采用浓硫酸高温强化焙烧、水浸、除杂工艺生产硫酸稀土溶液,萃取转型常用镁盐皂化有机相的方式,水浸及皂化过程引入的钙离子与硫酸根结合产生硫酸钙。过饱和硫酸钙极易在生产设备中结晶,堵塞相口和管道,严重时经常导致生产无法正常进行,是制约稀土分离的瓶颈。通过设计降钙工艺来改善萃取生产线的结晶程度,延长生产线清理周期。研究结果表明,硫酸钙晶种添加浓度为50 g/L~60 g/L、搅拌时间60 min~80 min、搅拌强度350 rpm~400 rpm、陈化时间60 min~80 min、反应温度为常温、初始钙离子浓度2 g/L~3 g/L时,降钙率达到50%以上。能有效延缓稀土萃取转型及分离生产线上硫酸钙结晶,具有一定的实际指导意义。
Baotou mixed rare earth concentrate is used to produce rare earth sulfate solution usually by concentrated sulfuric acid high temperature roasting,water immersion and removing technology.Magnesium salt saponification is adopted for extraction transformation,and calcium ions produced during water immersion and saponification are introduced to combine with sulfate in the solution to produce calcium sulfate.The supersaturated calcium sulfate crystallizes easily in the production equipment,and blocks the phase ports and pipelines,even lead to the failure of normal production,and is the bottleneck restricting the separation of rare earth.By reducing the concentration of calcium ions in the solution,the crystallization degree of extraction production line was improved,and cleaning cycle of the extraction line was prolonged.The results showed that under the conditions of calcium sulfate crystal seed adding amount 50 g~60 g,mixing time 60 min~80 min,stirring intensity 350 rpm~400 rpm,aging time 60 min~80 min,ambient reaction temperature,and initial concentration of calcium ions 2 g/L~3 g/L,calcium reduction rate is above 50%.The research findings are expected to provide practical guiding for the delay of calcium sulfate crystallization during rare earth extraction transformation and separation.
作者
李虎平
韩满璇
胡广寿
王斌
田斌
LI Hu-ping;HAN Man-xuan;HU Guang-shou;WANG Bin;TIAN Bin(Gansu Rare Earth New Material Limited-liability Company,Baiyin 730922,China)
出处
《稀土》
EI
CAS
CSCD
北大核心
2021年第1期93-98,共6页
Chinese Rare Earths
关键词
稀土萃取分离
硫酸钙
结晶
降钙
rare earth extraction and separation
calcium sulfate
crystallization
calcium reduction
