某火山岩型铀矿石二段逆流搅拌浸出试验研究

Experimental study on a volcanic rock type uranium ore by two stage countercurrent agitation leaching

某火山岩型铀矿石组成复杂,Ca、Mg、Al的总质量分数为15.48%,主要耗酸物质为绿泥石、方解石和磷灰石。常规搅拌浸出试验表明,该铀矿石酸法浸出的尾渣铀质量分数可降低至0.013%,酸用量高达25%,浸出液余酸质量浓度为82.5g/L,铀浸出率89%。而加压碱浸时的铀浸出率只有72%。根据试验铀矿石需要用高余酸分解磷灰石的浸出特征,开展了二段逆流搅拌浸出的试验研究,与常规一段浸出相比较,可以节省酸用量26%。

The composition of a volcanic type uranium ore is complex, total content of calcium, magne-sium and aluminum is 15.48%. The main acidic consumption minerals are chlorite, calcite and apa- tite. Conventional agitation leaching experimental results show that when acid usage content is 25%, and spent acid concentration in the leached solution is 82.5 g/L, the content of uranium ia the leached tailing is reduced to 0.013%, and leaching rate is 89%. But the uranium leaching rate is only 72% by alkaline pressure leaching. By the uranium ore characteristics which need higher spent and concentra- tion to decompose apatite, two stage countercurrent agitation leaching experiment was carried. Com- pared with conventional agitation leaching experimental result, two stage countercurrent agitation leaching experiment can save 26 % of acid.