离心萃取器在黄金萃取中的应用

摘要

传统的金萃取过程为间歇作业，存在操作不连续和有机相损失大等缺点。而离心萃取器作为一种新型的高效萃取设备，具有萃取效果好、可连续操作和操作弹性好等优点，因而在液-液萃取中得到广泛应用。对离心萃取器在金萃取过程中的萃取性能进行了实验研究，结果表明：在保证DBC不发生乳化的前提下，转鼓的最大转速为3000 r/min；随着转鼓转速的增大，金萃取率先显著增大，而后增速减缓，而流比的减小使得转速对萃取率的影响减弱；随着流比的减小，萃取率逐渐降低，且降低速度逐渐增大，而转速的增大使得萃取率随流比的变化幅度增强；随着萃取级数的增大，萃取率迅速增加，但增加速度逐渐减小，最终达到稳定。对含金料液进行4级连续逆流萃取，控制转鼓转速为2000 r/min，流比O/A=1∶3，金萃取率可达98%以上。%Traditional gold extraction is an intermittent process,that has such problems as long operation time, large organic phase-loss and so on.As a new type of high efficient extraction equipment,the centrifugal extractor has the advantages of high efficiency,continuous operation and high operating elasticity,so it is widely used in liquid-liquid extraction.The application of centrifugal extractor in gold extraction was studied.The results show that the max rotation speed is 3 000 r/min under the premise that DBC is not emulsify.With rotation speed increasing,the extractability increases obviously first and then the increase rate slows down gradually,but the decrease of the phase ratio delays this tendency.With the decreasing of phase ratio,the extractability decreases gradually,the decrease rate becomes more significant,and this tendency is also enhanced by the increasing of rotation speed.With the increasing of extraction stages,the extractability increases rapidly,but the growing rate decreases,and finally reaches a steady state.Four stages of counter-current extraction was carried out in centrifugal extractor.Under the conditions of 2 000 r/min rotation speed,O/A=1∶3,the extractability could be arrived at 98%.