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Introduction Ore Processing Fire Assaying

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In order to model reclamation of the model heap, the model heap is exhaustively rinsed to recover all the ore and to clean the heap so it can be returned to natural use.

Study reclamation of a heap leach pad by removing the soluble metals from the pile through repeated rinsing. (How is it possible to tell that the pile is clean? Analyze for chemicals that are limited by drinking water standards. In this case, check for copper in solution by adding ammonium hydroxide. The dark blue ammonium-copper complex extends the visible detection limit of copper.)
To check for the presence of copper in the apparently clear solution after exhaustive leaching of the model heap, ammonium hydroxide (from the grocery store) is added. The dark blue color much more visible to the eye is a complex of ammonia and copper ion. The orange precipitate to the right is iron hydroxide (rust) because in this case, the simulated ore included a lot of iron pyrite, some of which leached into the model pregnant solution.

Prepare the heap leach pad for reclaimed use. (What else must be considered? Slope stability, soil preservation methods)

 

 

SUGGESTED FOLLOW-UP (DISCUSSION)

What problems were encountered with the leaching? The fines in the "ore" sample clogged the filter. The solution did not go all the way through the heap. Some may not have gotten wet.

How could those problems be overcome? The fines could be eliminated through agglomeration. Solutions could be added to the leach so the rocks got completely wet. The angle of the heap pad could be changed and the spraying could be placed carefully so the solution has to go through the whole leach heap.

 

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