摘要
为了考察微波功率、辐射时间和物料质量对铀矿石浸出率和浸出周期的影响,采用频率为2.45 GHz微波对花岗岩铀矿石进行加热,然后配置了不同预处理条件下的铀矿样进行室内柱浸试验,并分析了不同微波功率预处理时铀矿石比表面积和孔隙率的变化。研究结果表明:微波预处理的温度应控制在600℃以下。当微波功率为40 k W,辐射时间为40 s,矿石质量为4 kg时,铀浸出率为85.27%,浸出周期为67 d,较原矿浸出率提高7.69%,浸出周期缩短25 d。4 kg矿石经40 k W微波辐射120 s后,比表面积较原矿增大39.9%,孔隙率增加71.8%。利用扫描电镜(SEM)观察微波预处理前后表面形貌,预处理后原有微裂隙扩展并加深,并出现新的裂缝。微波预处理改善了铀矿石渗透性,有利于浸出。
In order to study the effects of microwave power,irradiation time and ore weight on uranium leaching rate and leaching time,a granite uranium ore was pretreated by 2. 45 GHz microwave,and then these uranium ore samples pretreated under different condition were prepared for indoor column leaching test. Meanwhile,the changes of specific surface area and porosity of uranium ore under different pretreatment conditions were analyzed. The results showed that the pretreatment temperature should be controlled under600 ℃. The microwave power of 40 k W,the irradiation time of 40 s,the material weight of 4 kg were the optimal pretreatment condition. Under the condition,the leaching rate of uranium rose to 85. 27%,7. 69% higher than the control group,and the leaching time of uranium was shortened to 67 d,25 d shorter than the control group. After irradiating 120 s with microwave power of 40 k W,the specific surface area and porosity of uranium ore increased by 39. 9% and 71. 8%,respectively. The scanning electron microscopy（ SEM） observation showed that the existing crack was deepened and new cracks were developed inside ore after irradiating. Microwave pretreatment was more favorable to leaching because it improved the permeability of uranium ore.
出处
《稀有金属》
EI
CAS
CSCD
北大核心
2016年第3期280-286,共7页
Chinese Journal of Rare Metals
基金
国家自然科学基金重点项目(U1401231)资助
关键词
微波预处理
堆浸铀矿石
比表面积
孔隙率
microwave pretreatment
heap leaching uranium ore
specific surface area
porosity
