I think the idea to avoid leaching is ESG driven,allowing for an...

I think the idea to avoid leaching is ESG driven,allowing for an easier and hopefully faster permitting regime..........

• Heap leaching process

The mined ore is crushed to a certain size by the crusher. Because the leaching stage does not need to reach the same small particle size as the flotation process, the heap leaching process does not need a grinding stage, the ore can be directly sent to heap leaching after crushing. The oxide ore (mix with partial sulfide ore) is placed on a leaching pad and sprayed with the strong acid solution to permeate the crushed ore. As time goes on, the copper in the crushed ore is leached into the solution as the pregnant solution, and then pumped into solvent extraction equipment for further purification.

• Pool leaching

The pool leaching process is a common leaching method used in early wet copper smelting. Using the strong sulfuric acid solution to leach the 1-2% copper-contained oxidized ore (particle size is -1cm). Because the concentration of copper in the leach solution is high, it can be directly used for the copper electrodeposition.

• In-situ leaching process

During in-situ leaching, the well spacing is generally 30x30cm (or 15×7.5m), and the diameter of the borehole is 15-25cm. A plastic pipe is set in the hole through the ore body, and the leaching agent flows into the ore body along the plastic pipe, the leaching solution is pumped back to the ground from the bottom of the ore body.
The in-situ leaching process can be used to treat the residual ore of old mines or the unmined oxidized copper ore and lean copper ore. The in-situ leaching process has better potential than other processes for those abandoned mines or uneconomical copper mines with other processes.

• Agitation leaching process

Agitation is carried out in the leaching tank equipped with the agitation leaching device. The fine grains (-75um accounts for 90%) oxidized ore or calcined sulfide ore are leached by high concentrated sulfuric acid solution. There are two ways of leaching: air agitation and mechanical agitation.
Because of the small particle size and sufficient agitation, the agitation leaching process has a faster leaching speed and higher recovery rate than the pool leaching process. Therefore, the agitation leaching process can treat high-graded ore or the ore with lower-graded tailings (Cu < 1%).