压力波动法地浸采铀的数值模拟初步研究  

Numerical study on in-situ leaching uranium with pressure fluctuation

作　　者：魏宁[1] 李小春[1] 朱前林[1] 刘乃忠[2] 苏学斌[2] 王晓东[2] 

机构地区：[1]岩土力学与工程国家重点实验室中国科学院武汉岩土力学研究所,武汉430071 [2]核工业北京化工冶金研究院,北京101149

出　　处：《铀矿冶》2011年第3期124-129,共6页Uranium Mining and Metallurgy

基　　金：国家自然科学基金资助项目(40902073)

摘　　要：目前国内外的地浸研究侧重地浸化学机制及工艺,不能很好地解决铀矿层非均质性引起溶浸流体非均质流动带来的"非优势流动区域"和"溶浸死区"等问题。基于流动传质理论、室内试验和注气现场试验,笔者提出了压力波动溶浸开采的方法,即采用高压缩性的气液混合溶浸流体进行压力波动条件下的地浸开采。基于分散相气液混合流体特性和流动-反应-传质理论,采用COMSOL-Multiphysics软件模拟了传统中性地浸和压力波动法地浸的采铀过程。数值模拟结果显示:压力波动过程中,溶浸流体在矿层中胀缩变形,可促进高渗透区域与低渗透区域的流体流动传质过程,特别是低渗区域的对流-弥散传质作用;铀回收率随压力波动次数变化而变化,回收率曲线明显区别于传统地浸回收率曲线,铀回收速率和回收率提高。初步结果表明,压力波动法地浸对提高非均质铀矿层的回收速率和回收率在技术上具有可行性。Recent researches and innovation of in-situ leaching focus on the chemical process,which can not solve the low recovery in＂dead leaching zone＂ and ＂non-preferential zone＂ caused by preferential flow and solute transport phenomena in heterogeneous ore deposits.Based on hydrodynamic effects and phenomena in highly heterogeneous porous media,gas injection experiments and laboratory experiment results,an innovative method for in-situ leaching,named as leaching with pressure fluctuation,was put forward to enhance the leaching effect and uranium recovery,especially in those uranium ore deposits with high heterogeneity.Based on the characteristics of gas/liquid mixture and flow-reactive-transport theory,a numerical modeling tool is established.By the numerical simulation,the field-scale traditional leaching method and the new method were studied.The simulation results show that the gas-liquid mixture will expand/shrink greatly in different flow zone during the pressure fluctuation process,and the deformation will enhance the solute transport effect among different flow zones,especially in non-preferential flow zone,and enhance the uranium recovery.The primary results show that in-situ leaching with pressure fluctuation is feasible technically.

关 键 词：地浸采铀 非均质 优势流动传质 高压缩性流体 压力波动 

分 类 号：P641.3[天文地球—地质矿产勘探] TD853[天文地球—地质学]