一、前言 粒度小于0.1mm左右的砂金,用重选法回收效果并不佳。过去不能经济有效地回收这样的细粒金,现在情况却有所改善。在新西兰,许多含金海滩砂砾中含有大量的重矿物,细粒金的表面具有疏水性,因而存在采用浮选法回收它们的可能性。应用传统的机械浮选机是有效的,但必须有粗、精、扫选的配置才能保证产品的低产率和高回收率;但是,难以保证粗粒矿物和重矿物的充分悬浮。在科罗拉多河砂中的细粒金采用充气旋流器回收是有效的,但对新西兰的粗粒的和重的海滨砂金则是无效的。而浮选柱对处理这些砂矿又是很有前途的,可获得产率 First, the preface Granularity less than about 0.1mm placer gold, re-election method recovery effect is not good. In the past, such fine grain gold could not be recovered economically and effectively, and the situation has now improved. In New Zealand, many gold-bearing beach grit contains a large amount of heavy minerals and the surface of fine grained gold is hydrophobic, so there is a possibility that they may be recovered by flotation. The use of conventional mechanical flotation machines is effective, but coarse, fine, and sweep configurations are required to ensure low yields and high recoveries; however, it is difficult to ensure adequate suspension of coarse and heavy minerals. Flotation of fine-grained gold in Colorado river sand using an aerated cyclone is effective, but it is ineffective for New Zealand’s coarse and heavy seashore placer gold. The flotation column for the treatment of these ores is very promising, yield can be obtained