Closed-circuit method for improving refractory gold ore concentrate quality and recovery rate

Abstract

A closed-loop method for the gold ore difficult to dress to increase the grade and recovery rate of gold ore concentrate includes such steps as dissolving sodium pyrophosphate (Na4P2O7.10H2O) in water to obtain solution, adding it to crude ore slurry while stirring to obtain the primary ore concentrate, adding said solution while stirring to obtain the primary fine ore concentrate, refining to obtain the final ore concentrate, and returning all failings back for further dressing.

Description

1. Technical field [0001] The invention relates to a closed-circuit method for improving the grade and recovery rate of gold concentrate in refractory gold mines. 2. Background technology [0002] As the world's gold production continues to increase year after year, there are fewer and fewer easy-to-separate ores in nature, and it has become an inevitable trend to extract gold from difficult-to-separate gold ores. [0003] The properties of refractory gold ores are very complex. First, gold is distributed in a variety of gold-bearing minerals in ultramicroscopic form; second, there are many kinds of gangue minerals, including silicate, aluminosilicate minerals, and carbonate minerals; Third, it contains clay minerals that are easy to muddy. These unfavorable factors seriously affect the beneficiation index. The usual practice is to use lime, water glass, sodium fluorosilicate, cyanide, etc. as inhibitors for flotation. Lime is mainly used as an inhibitor of pyrite in gold...

AI Technical Summary

Problems solved by technology

Lime is mainly used as an inhibitor of pyrite in gold ore, but it also has an inhibitory effect on gold minerals; water glass is mainly used as an inhibitor of silicate and other gangue minerals, but it has an inhibitory effect on carbonate minerals and aluminosilicate Salt minerals have poor inhibitory effects; cyanide is mainly used as a metal sulfide and pyrite inhibitor, but it also has a strong inhibitory effect on gold and can dissolve gold, causing gold to be lost to tailings, and its toxicity is also serious Environmental issues

In addition, there are organic substances used as inhibitors, but due to limited sources or expensive prices or unsatisfactory inhibitory effects, they are rarely used in industrial applications at present.

For example, the Dongbeizhai Gold Mine in Sichuan, my country is a very large gold mine, but it is also recognized as an extremely difficult arsenic-rich carbon fine-grained gold mine at home and abroad. Some authoritative organizations in China have conducted flotation tests on it: once obtained If the grade of gold concentrate is 18-20 g / t, the recovery rate is about 90%; if the grade of gold concentrate is increased to 25 g / t, the recovery rate will drop to about 75%, that is, the gold concentrate of refractory gold ore cannot be recovered. Increased ore grade and recovery

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