十红滩砂岩型铀矿床南段地浸条件分析

Analyzed the conditions of leaching uranium in south area of Shihongtan uranium deposit

分析了十红滩铀矿床南段的地层结构、地球化学、矿物成分和化学组成、水文地质、水文地球化学等特征。结果表明:矿层具有地浸必要的稳定隔水顶、底板,埋藏深度适宜,但含水层连续性不好,存在多层钙质夹层;铀矿物以沥青铀矿为主,与黄铁矿、方解石紧密共生,矿石中的SiO2偏低,Al2O3、CaO、Fe2O3偏高,易产生Ca、Fe等化合物的沉淀;铀矿石中以四价形式存在为主,六价铀偏少,提高铀的浸出率难度大;地下水矿化度过高,水中的硫酸钙及碳酸钙的饱和指数都大于零。因此,南矿段地浸条件决定了无论采用常规的规酸法或与碱法开采都无法正常进行高效的浸出,新的工艺研究势在必行。

It was analyzed that the characteristic of stratum configuration, geochemistry, mineral composition and chemic component, hydrogeology and hydrogeochemistry in the southern of Shihongtan uranium deposit. The characteristic of leaching uranium in the area as fellow ： there are stable top and bottom aquifuge in the aquifer, but there are aquitard or impervious in the aquifer, so the aquifer is discontinuity. Uraninite is primary mineral and intimate intergrowth with pyrite and calcite. There are lower SiO2 but higher Al2O3 ,CaO,Fe2O3 content in mineral. The hexavalent uranium is few but the tetravalent is more in uranium mineral. The total dissolve solid in groundwater is higher than demand of leaching, because the saturation index of CaSO4 and CaCO3 more than 0. The characteristics of leaching imply that it is impossibility that natural and effectible leaching uranium not only acid leaching and also alkaline leaching. So, ameliorating condition and technology of leaching uranium are necessary.