CO2+O2浸出工艺溶浸通道堵塞控制措施探究

在地浸采铀浸出过程中，渗透性是决定浸出效率的重要因素，保持良好的渗透性对铀的浸出具有举足轻重的作用。目前，矿层结垢堵塞溶浸通道致使矿层渗透性降低影响浸出效率，是各地浸矿山运行中存在的普遍问题。基于对纳岭沟铀矿床水文地质条件及CO2+O2地浸采铀试验过程中主要沉淀物的生成机理分析，旨在针对矿层渗透性降低的情况，通过分析浸出过程中沉淀物类型及特性，探究沉淀物生成及堵塞矿层的主要原因，提出通过采区投入运行前20~30 d内加入CO2进行微酸预酸化直至HCO3-浓度维持在1 000 mg/L，调节溶浸通道环境，保持主要沉淀物高溶解度；随后注氧氧化，控制余氧含量为20 mg/L左右；摒弃目前袋式过滤方式，采用活性炭、石英砂、阳离子树脂等集中过滤方式，有效去除溶浸液中的有害金属离子，减少回注矿层形成二次沉淀等主要技术措施，有效控制沉淀物在溶浸通道的生成与积累，实现地浸铀矿山高效浸出运行。

Study on the control measures for the blockage of solution channel in CO2 + O2 leaching process

In the process of ground leaching uranium aching, permeability is the important factor that determining the leaching efficiency, and maintaining good permeability plays an important role in uranium leaching. At present, the blockage of the mineral layer scale reduces the mineral layer permeability and affects the leaching efficiency is the general problems existing in the operation of immersed mines. Based on the hydrogeological conditions of Naling ditch naluranium deposit and the generating mechanism of main sediment in CO2 + O2 underground uranium extraction test, to address the reducing permeability of the ore layer, by analyzing the type and characteristics of the sediment during the leaching process, to explore the main reasons of sediment generation and blockage of mineral layer, proposing to add CO2 for micro-acid pre-acidification within 20 to 30 days before the mining is operation until the HCO3-ion concentration is maintained at 1 000 mg/L, and adjust the environment of immersion channel, keep the main sediment at high solubility; Then inject oxygen for oxidation, and regulate the residual oxygen content at about 20 mg/L; Moreover, instead the current bag filtration method, the technical measures, such as the centralized filtration method, such as activated carbon, quartz sand, and cationic resin, removing the harmful metal ions from the dissolved solution effectively, reducing the formation of secondary precipitation in reinjection layer was used in the study, to control the generation and accumulation of sediment in the soluble immersion channel effectively, thus realize the efficient leaching operation of ground-dip uranium mines.