岩石流体反应–流动耦合试验装置的开发  

DEVELOPMENT OF ROCK-FLUID REACTION-FLOW COUPLING TESTING APPARATUS

作　　者：魏宁[1] 李小春[1] 王颖[1] 王燕[1] 

机构地区：[1]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,湖北武汉430071

出　　处：《岩石力学与工程学报》2008年第7期1499-1504,共6页Chinese Journal of Rock Mechanics and Engineering

基　　金：中国科学院知识创新工程青年人才领域前沿项目(O731071Q01)

摘　　要：原地溶浸采矿过程是一个典型受化学反应、流体流动以及物质迁移等多种因素非线性耦合作用的复杂过程。原地溶浸采矿过程中,伴随溶浸过程,矿层的渗透性分布会发生非常大的变化,这可能加剧矿层的非均匀性,使得溶浸剂和溶浸液在矿层中会发生非均匀流动现象,降低溶浸的范围和矿层的采收率。国内外现有的溶浸试验装置侧重于化学分析,不能很好地反映地浸现场条件下的高应力、高流体压力条件和流体流动的特点,同时在测量范围、精度上也不能满足科学研究的要求。为此研制岩石流体反应–流动耦合试验装置,该装置可以严格控制岩体应力和流体温度,实时在线监测系统内的流体压力、流量以及温度,实时分析流体的化学成分和岩芯的渗透性,通过分析手段可获得溶浸过程中的反应动力学参数和岩体成分等性质,实现对岩石流体反应流动耦合过程的全面分析。结合新型天然成因试剂地浸采铀法,在该试验装置上进行原状砂岩地浸试验,分析地浸过程中砂岩的渗透性、溶浸流体化学成分及铀矿采收率的变化情况。其中,当液固比为4时,铀的采收率接近60%,地浸过程中岩芯的渗透系数变化跨越3个数量级。这些试验数据显示,该装置的试验效果良好,加氧条件下矿层原地液地浸采铀是可行的,但渗透性的高度变异会影响到现场地浸的采收速率和采收率。In-situ leaching（ISL） is a typical flow process coupled with chemical reaction and solute transport.The permeability distribution of porous ore deposits will change dramatically during leaching process,and it may lead to preferential flow or ＂dead leaching zone ＂that decreases the overall recovery rate of minerals.Existing leaching apparatuses mainly focus on the chemical process under atmospheric pressure,and can not perfectly model the in-situ condition with high confining pressure and fluid pressure.Permeability of uranium orebody may change by several orders of magnitude during leaching process.These apparatuses are not suitable for high precise and large-scale permeability monitoring.For these reasons,a new rock-fluid reaction-flow coupling testing apparatus is developed.The flow rate,pressure,different pressure,fluid component can be gained simultaneously with this apparatus.Permeability,solution transport coefficient,and chemical reaction rate can be obtained by analytical methods.The apparatus is used for natural reagent leaching experiment with natural ore bearing aquifer groundwater.Experiment results show that uranium recovery rate is about 60% when the liquid solid ratio reaches 4,and permeability changes by 3 orders of magnitude during natural reagent leaching process.The experiment proves that the rock-fluid reaction-flow coupling testing apparatus works well and efficiently,and in-situ uranium leaching by natural ore bearing aquifer groundwater under oxygen oxidizing condition is applicable and effective.The results also show that field leaching experiment may face non-uniformity flow which will decrease recovery rate.

关 键 词：岩石力学 溶浸 反应–流动过程 渗透性 原地溶浸 

分 类 号：TU45[建筑科学—岩土工程] TL212.12[建筑科学—土工工程]