Exploratory Study of Gold Recycle from the Tailing of All-sliming Cyanidation CIP

摘要

Gold ore is processed by all-sliming cyanidation CIP (carbon in pulp) at a gold mine in Gansu province of China. The leaching residue (tailing) Au grade is about 0.52 g/t, which is much valuable to be recovered. Mineralogical analysis shows that the loss of gold in leaching residue is mainly organic carbon adsorption gold and inclusion gold, accounting for 45.55% and 54.45% respectively. The inclusion gold is mostly wrapped by ganguc and metallic mineral separately, accounting for 35.56% and 18.89%. Excluding the gold in gangue, both the gold adsorbed by organic carbon and wrapped in metallic mineral could be recycled by flotation process. Study has been carried out for recovering gold in cyanide residue by solely column flotation apparatus. During the semi-industrial test, B and E type sparger were adopted in flotation columns to evaluate their influence on process performance. To further improve metallurgy technology the ultrasonic device was introduced into flotation column tank. The results showed that ultrasonic pretreatment is negative influence, and the E type sparger is better than B type sparger. The concentrate Au grade is up to 10.14g/t, and34.3% of Au lost in tailing was recovered while feed grade being 0.52g/t. The column flotation process was proven being a proper way to recycle gold from the tailing of all-sliming cyanidation CIP.