Gold-arsenic-bismuth ore dressing technology
SUZHOU OCAN POLYMER MATERIAL CO.,LTD , https://www.ocanplasticgroup.com
Of a gold mine in Guizhou is a low-temperature hydrothermal deposits, ore structure, structure and composition of matter is more complex. The type of ore process is a hard-to-select, difficult-to-dip Carlin-type gold ore.
Metallic minerals ore mainly pyrite, arsenopyrite and followed stibnite, there is a small amount of sphalerite, cinnabar, natural mercury, yellow copper ore, galena, natural antimony. Metallic minerals account for 4.12% of the total ore, and gangue minerals are mainly quartz , calcite , and graphite .
The ore gold grade is 5.47g/t. Gold is mainly composed of fine-grained natural gold, of which medium-grain gold (0.053～0.037mm) accounts for 6.12%, fine gold (0.037-0.01mm) accounts for 5.99%, and fine-grained gold (less than 0.01mm) accounts for 18.11%. The secondary microscopic gold is 69.78%, that is, 69.78% of the gold inclusions are present in pyrite, arsenopyrite, stibnite (gold accounted for 66.66%) and gangue.
For this refractory ore, the enhanced flotation closed-circuit process (see Figure 1), the gold recovery rate increased from 70% of conventional flotation to over 91%, and the gold grade of tailings decreased from 2g/t to 0.5g/t.
Figure 1 Flotation closed circuit test process
The experimental research proves that:
1. Sodium carbonate is added into the grinding medium. The slurry is aerated and stirred, pre-oxidized, increasing the oxidation time of sodium carbonate and gold-bearing minerals, and removing the surface pollution of gold minerals, which can improve the recovery rate of gold;
Second, the use of copper sulfate as an activator of arsenic pyrite and stibnite, prolonging the stirring time, can fully oxidize the mineral;
3. In the acidic medium, copper sulfate is used as the activator, and the two collectors of butylammonium black and butyl xanthate are used in proportion to produce a synergistic effect, increase the collection performance, and improve the selectivity. Increased gold recovery rate.