地浸采铀过程中含矿层渗透性演化的示踪试验

铀资源既是核军工基石又是核电发展的粮仓，在当前复杂的国际形势与大力发展核电的时代，更是一种不可或缺的重要资源。随着内蒙古巴彦乌拉铀矿地浸采铀的运行，矿层堵塞、铀浸出量下降等问题逐渐浮现。为探明地浸采铀过程中含矿层渗透性的演化特征，在巴彦乌拉铀矿床C10采区某试验单元开展了井间示踪试验。试验结果表明，地浸一年后含矿层砂岩孔隙度与渗透性降低，其原因与含矿层砂岩孔隙发生堵塞有关。地浸二年后C10采区试验单元在三个渗流方向即KZ13238-KC13036、KZ13238-KC13038和KZ13238-KC13438方向均产生了优势渗流通道。地浸二年后各方向渗流通道溶浸液流速较地浸一年均有不同程度降低，且下降幅度相较于前一年更大。表明随着采区的运行，含矿层孔隙堵塞情况日益严重，含矿层渗透性不断降低。研究结果可以为地浸中含矿层渗透性演化特征提供示踪证据。

Tracer Test of Permeability Evolution of Ore-bearing Layer during In-situ Leaching of Uranium

Uranium resources are not only the cornerstone of nuclear military industry but also the granary for the development of nuclear power. In the current complex international situation and the era of vigorously developing nuclear power, it is an indispensable and important resource. With the operation of in-situ leaching of uranium at Bayanwula uranium mine in Inner Mongolia, problems such as ore bed blockage and decreased uranium leaching amount are gradually emerging. In order to explore the evolution characteristics of the permeability of ore bearing layers during in-situ leaching of uranium, a cross-well tracer test was conducted in a certain experimental unit of the C10 mining area of the Bayanwula uranium deposit. The experimental results indicate that after one year of in-situ leaching, the porosity and permeability of the sandstone in the ore bearing layer decrease, which is related to the blockage of the pores in the sandstone in the ore bearing layer. After two years of in-situ leaching, the C10 mining area test unit has developed advantageous seepage channels in three seepage directions, namely KZ13238-KC13036, KZ13238-KC13038, and KZ13238-KC13438. After two years of in-situ leaching, the flow rate of the solution in the seepage channels in all directions decreases to varying degrees compared to that in the first year of in-situ leaching, and the downward decrease is greater than the previous year. It indicates that with the operation of the mining area, the pore blockage of the ore bearing layer is becoming increasingly serious, and the permeability of the ore bearing layer is continuously decreasing. The research results can provide tracer evidence for the evolution characteristics of the permeability of ore-bearing layer in in-situ leaching.