All slime cyanidation-countercurrent method is successfully applied to a gold mine

The original beneficiation process of the gold mine was all slime cyanidation CIP process. Because  of the change of mining method, the mud content reached more than 15%, which  makes the leaching period longer and limited processing capacity; the flotation  recovery rate decreased; the production cost became higher. Xinhai needed to change  the process to reduce the cost. 

After contracting this gold reconstruction  project, Xinhai decided to take the test with all slime  cyanidation-countercurrent washing-carbon solution method, because the required leaching ore particle of this new process is larger than the process of  original process.

The problems of all slime cyanidation CIP process 

This process required the leaching ore  granularity is fine, -200 mesh accounted for 85%, but the gold mine granularity  is coarse, and the mill processing capacity is limited resulting in the entire  gold processing decreasing, and the cost of ore dressing increasing; secondly, carbon leaching carbon was weared seriously reaching 120g/t according to Xinhai  Research Institute testing; so the overall economic benefits were low. 

The all slime cyanidation-countercurrent  washing-carbon solution method designed by Xinhai Mineral Processing Research  Institute adopted classifying control and thickening before leaching. The  details of the test as follow

1. Leaching rate kept stable while the  leaching ore particle size was changing in certain range.

2. Ore pulp would not become layering with  the strong agitation.

3. The low pulp concentration did not  affect the leaching because of the simple ore properties and fast leaching  speed.

Technology Index Comparison

According to the comparison, it showed that  the mineral dressing recovery rate was the same, but the cost of all slime  cyanidation-countercurrent washing-carbon solution method saved 15.06 Yuan/ton  which brought benefits over 3 millon Yuan per year.