摘要
铀资源是的世界上重要的战略资源,如何安全高效开发利用铀资源,对保障国家能源供应和国家战略安全意义重大。CO_(2)+O_(2)地浸采铀是砂岩型铀矿采冶的主要方式,研究CO_(2)+O_(2)溶浸过程中水动力场和化学场的耦合机制是预测地浸采铀过程中铀动态浸出的关键核心。以内蒙古某煤铀共存矿床为对象,通过COMSOL构建地浸过程中溶质运移的对流与弥散模型,通过PHREEQC构建砂岩型铀矿CO_(2)+O_(2)溶浸过程的热力学数据库,利用iCP平台(Interface COMSOL-PHREEQC)建立COMSOL-PHREEQC耦合框架的CO_(2)+O_(2)地浸采铀的反应运移数值模型,模拟了CO_(2)+O_(2)地浸过程中铀矿动态浸出过程。同时,基于参数敏感性分析定量比较了不同参数对铀浸出效果影响的重要性程度。研究结果表明,本模型能够模拟预测CO_(2)+O_(2)溶浸过程中铀的反应运移过程。模拟结果发现CO_(2)+O_(2)地浸采铀过程中,抽、注液孔周围水动力强,溶浸液与铀矿物发生强烈的化学反应,形成高浓度的铀区;在水动力作用弱的地方,溶浸液不能及时到达,形成低浓度铀区。浸出铀的运移过程主要受对流和弥散作用控制。浸出铀可以通过下部煤层采动裂缝进入采煤工作面和采空区内,影响煤矿安全开采活动。参数敏感性分析结果揭示抽液流量、CO_(2)和O_(2)体积分数是铀浸出率的关键控制因素,而铀的浸出率与地层渗透率、地下水流速之间并不是呈单调的递增关系。研究结果对砂岩型铀矿CO_(2)+O_(2)地浸开采具有一定的指导作用。
Uranium resource is important strategic resource in the world.How to develop and utilize coal⁃uranium re⁃sources safely and efficiently is of great significance for ensuring national energy supply and national strategic security.The CO_(2)+O_(2)in⁃situ leaching of uranium is the main way of mining and smelting sandstone⁃type uranium mines.Stud⁃ying the coupling mechanism of hydrodynamic field and chemical field during the CO_(2)+O_(2)leaching process is the key to predicting the dynamic leaching of uranium in the process of CO_(2)+O_(2)in⁃situ leaching.In this study,a coal⁃uranium coexisting deposit in Inner Mongolia is taken as the object,the convection and dispersion model of solute mi⁃gration in the in⁃situ leaching process is constructed by COMSOL,and the thermodynamic database of the CO_(2)+O_(2)dis⁃solution process of sandstone⁃type uranium ore is constructed by PHREEQC.Using the iCP platform(Interface COM⁃SOL-PHREEQC),a numerical model of the reaction and migration of CO_(2)+O_(2)in⁃situ leaching of uranium in the COMSOL-PHREEQC coupling framework is established,and the dynamic leaching process of uranium ore during CO_(2)+O_(2)in⁃situ leaching is simulated.Meanwhile,the importance of different parameters on the uranium leaching effect is quantitatively compared based on parameter sensitivity analysis.The results show that this model can simulate and predict the reaction and migration of uranium in the process of CO_(2)+O_(2)leaching.The simulation results show that in the process of in⁃situ leaching of uranium with CO_(2)+O_(2),the hydrodynamic force around the pumping and injection wells is strong,and the leaching solution has a strong chemical reaction with uranium minerals,forming a high concen⁃tration uranium area,while in the place with weak hydrodynamic action,the leaching solution cannot reach in time,forming low concentration uranium areas.The migration process of leached uranium is mainly controlled by convection and dispersion.The leached uranium can enter the working face and goaf through the mining fractures in the lower coal seam,affecting the safe mining activities of the coal mine.The results of parameter sensitivity analysis reveal that the ex⁃traction flow rate,CO_(2),and O_(2)concentration are the key control factors of the uranium leaching rate,while the uranium leaching rate is not monotonously increasing with formation permeability and groundwater flow rate.The research re⁃sults have a certain guiding role in the CO_(2)+O_(2)in⁃situ leaching mining of sandstone⁃type uranium deposits.
作者
张海涛
张通
李旭
贺江辉
杨鑫
何玉鹏
邵则凡
ZHANG Haitao;ZHANG Tong;LI Xu;HE Jianghui;YANG Xin;HE Yupeng;SHAO Zefan(School of Earth and Environment,Anhui University of Science and Technology,Huainan 232001,China;Institute of Energy,Hefei Comprehensive Nation-al Science Center,Hefei 230031,China;State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines,Anhui University of Science and Technology,Huainan 232001,China;Uranium Industry Limited Company in China,Beijing 100013,China)
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2023年第S02期680-690,共11页
Journal of China Coal Society
基金
合肥综合性国家科学中心能源研究院资助项目(21KZS216)
国家自然科学基金资助项目(42272281)
安徽省教育厅资助项目(KJ2021A0441)。
作者简介
张海涛(1986-),男,安徽桐城人,讲师,博士。E-mail:entao0824@163.com;通讯作者:张通(1990-),男,山东济宁人,副教授,博士。E-mail:1099731996@qq.com。
