臭氧冰氧缓释剂的制备及其对某金矿滴淋堆浸的强化效果研究

钨作为一种稀有金属,目前主要应用于合金、电子和化工等领域,我国钨矿资源较为丰富,但多数属于难选矿物,其中具有开采经济价值的只有白钨矿和黑钨矿,但随着目前黑钨矿资源的减少,如何高效合理的利用白钨矿对国家经济的发展尤为重要。由于白钨矿和钙质脉石矿物具有相似的表面特性况且白钨矿作为脆性矿物,在破碎过程中容易产生微细粒,因此白钨矿与钙质脉石矿物方解石、萤石的有效分离和如何有效回收微细粒白钨矿是目前在浮选白钨矿所不可避免的两个难题。针对这两个问题,本文从白钨矿的晶体化学、浮选作用机理对浮选白钨矿进行了的介绍；此外还讨论了微细粒白钨矿的浮选工艺。其中白钨矿的晶体结构不同会使白钨矿表面呈现出不同的疏水性,进而影响白钨矿的可浮性。浮选作用机理方面根据作用效果阐述了抑制剂和捕收剂两类：无机抑制剂广泛的应用于白钨矿的浮选工艺中,；有机抑制剂对于白钨矿的浮选能达到很好的选择性；根据捕收剂性质以及特点,介绍了阴离子捕收剂、阳离子捕收剂、两性捕收剂以及组合捕收剂不同的作用效果,但大多数还处于理论研究阶段。微细粒白钨矿目前的浮选工艺主要有空化浮选、剪切絮凝浮选以及载体浮选三种方式,都是通过间接增加微细粒白钨矿的表观粒径,使微细粒白钨矿处于已易于浮选的状态,其优点是能减小微细粒白钨矿对浮选指标的影响,但未从根本上解决微细粒白钨矿浮选的问题。最后对白钨矿的浮选进行了总结。

Study on the enhancement effect of ozone ice as oxygen release agent on heap leaching of gold ore

One problem facing the gold heap leaching process is the oxygen deficit reducing the leaching rate and efficiency. In this research, ozone ice was prepared and embedded in the gold ore heap where additional oxygen was gradually supplied during the leaching process as the ice melted and ozone was decomposed. As a result, the generated oxygen would participate in the leaching and improve the gold leaching performance. The maximum ozone concentration of the 1-L ozone ice was obtained at 897.6 mg/L and the retention rate of ozone was about 90%. A column leaching device was designed and used for batch leaching tests on 50 kg gold ore samples of each batch. Ozone ice with ozone concentration of 600 mg/L were embedded regularly during a 21-day leaching period where sodium cyanide with the concentration of 300ppm was added at the rate of 6 L/(m2·h).The gold leaching rate was 55.08%, which was 10.48% higher than that of the blank control group.