某火山岩型铀多金属矿氯化焙烧试验研究

Experimental Study on Chloridizing Roast of a Volcanic Type Uranium Polymetallic Ore

针对某复杂火山岩型铀多金属矿石在常规浸出工艺条件下铀、铜、银综合浸出率低的问题,开展了添加氯化钠氧化焙烧—硫酸浸出铀和铜—氨化浸出银的工艺研究,重点考察了焙烧温度、氯化钠添加量、焙烧时间等对多金属综合浸出效果的影响。结果表明,通过氯化氧化焙烧,可促使硫化矿物的热分解,使其包裹的金属暴露出来,并对金属矿物产生氯化作用,从而有利于浸出,在氯化钠加入量3%、焙烧温度500℃、焙烧时间2 h的条件下可以获得较高的综合浸出率,铀、铜、银的浸出率可以分别达到88.24%、80.52%、90.88%,比常规浸出条件下分别提高了5.89、39.61、45.27个百分点。

In view of the low comprehensive leaching rate of uranium,copper and silver in a complex volcanic rock type uranium polymetallic ore under the conventional leaching process,the process of chloride oxygen roasting-sulfuric acid leaching of uranium and copper-ammonia leaching of silver is studied.The effects of roasting temperature,sodium chloride content and roasting time on the comprehensive leaching effect of polymetallic were examined.The test results show that through the chlorination oxidation roasting,it can promote the thermal decomposition of sulfide minerals,expose the wrapped metal,and produce chlorination on metal minerals,which is conducive to leaching.The experimental results show that a higher comprehensive leaching rate can be obtained under the conditions of 3%sodium chloride,500℃roasting temperature and 2 hours roasting time.The leaching rate of uranium,copper and silver can reach 88.24%,80.52%and 90.88%respectively,which is 5.89,39.61 and 45.27 per cent higher than that of conventional leaching conditions.