How to Process Gold Ores by Heap Leaching

Heap leaching is also a common gold extraction process and is considered to be the most economical gold extraction process at present. It has obvious advantages in low-grade and ultra-low-grade gold mine projects.

Heap leaching is widely used because of its simple process, easy operation, low energy consumption, low investment in equipment and infrastructure, and low cost.

Gold Heap Leaching Process Flow

Gold ore heap leaching process mainly includes six stages: ore preparation, leaching pad construction, heap building, leaching solution preparation, liquid distribution & collection, and pregnant solution processing.

(1) Ore preparation

It mainly includes crushing, granulation and pre-treatment.

Crushing is to ensure that the ore has good permeability;

Granulation is aimed at fine ore and ore with high clay content to improve the permeability of the ore pile;

Pre-treatment is to add solution leaching solution in the granulation process for pretreatment to improve the leaching rate of ore.

(2) Leaching pad construction

The bottom of the yard is laid before heap building, in order to collect the pregnant solution and prevent the leakage of the leaching solution.

(3) Heap building

Build ore piles with good and uniform permeability.

(4) Leaching solution preparation

Prepare leaching solution for heap leaching.

(5) Liquid distribution & collection

The liquid distribution is to spray the leaching solution evenly on the ore pile with the aid of the liquid distribution system;

Liquid collection refers to the collection of pregnant solution through the liquid ditch.

(6) Pregnant solution processing

The pregnant solution is deposited and extracted by means of activated carbon adsorption or desorption electrolysis system.

Although the gold heap leaching process is simple to operate and requires little investment, it may not be suitable for all gold mines. For a gold mine to choose what kind of beneficiation process and equipment, it still needs to be determined through the processing test.