How To Process Gold Ore In Yanacocha Gold Mine Peru

Yanacocha is South America's largest gold mine, located in the province and department of Cajamarca, approximately 800 kilometers northeast of Lima, Peru. Yanacocha’s operations are situated between 3,500 and 4,100 meters above sea level with development activities in four primary basins. The operation is a joint venture between Newmont (51.35%), Minas Buenaventura (43.65%) and the International Finance Corporation (5%)

The Yanacocha gold district is a 10x4km zone of altered rocks within a belt of tertiary volcanics that extends the whole length of Peru. Andesitic domes and dome complexes have been silicified and leached by epithermal gold-bearing solutions in at least nine distinct deposits. The mineralised sequences, which can also contain significant amounts of silver, are flanked by extensive argillitic alteration, and subsequent events have created siliceous breccia pipes with localised high gold grades.

How To Process Gold Ore In Yanacocha Gold Mine Peru
The process of gold from mining the first is drilling using Ingersoll-Rand DM45E and Atlas Copco machines and blasting are the responsibility of Minera Yanacocha. elimination of materials containing gold and silver began with drilling the ground to make a hole that will then condition with explosives..

The explosions carried out and the subsequent removal of ground begin to form large holes in the ground called pits. Stone materials have been destroyed and then transported by haul trucks ( which can load up to 250 tons of mineral rock) The ore is transported 2.5km or more to the leach pads using wheeled loaders and 85t-capacity trucks, and is heaped by stackers

Heap leaching is the process to extract precious metals like gold, silver, copper and uranium from their ore by placing them on a pad (a base) in a heap and sprinkling a leaching solvent, such as cyanide or acids, over the heap. This process dissolves the metals and they collect at the bottom of the pad.
Ground Preparation and pad construction: Here the soil on a slightly sloping ground is compacted and covered by an impermeable pad (can be made of plastic). Ore stacking: Then the crushed ore is stacked in the form of big heaps. Amount of fines is decreases as low as possible to improve permeability. Then the leaching agent such as cyanide or acid is sprayed over the heap. As, the reagent passes through the heap; the valuable metals get dissolved in it. The solution containing metal is drained from the heap and collected in a pond and the solution is sent for subsequent process for metal recovery to the processing plant.

With gold mineral processing plant ball mill trying to process the metal that can not be obtained by heap leaching. Gold recovered within 24 hours, unlike the heap leach process lasted almost 60 days. Construction began in mid-2006 and concluded in early 2008, with an investment of 270 million dollars and the production plan for 9 years. 1500 workers participated in the construction of this important project which has a processing capacity of 5,000,000 tons / year.

Carbon In Columns comprise the cyanide leach solution, and agitated in the leach tanks, and agitated with the ore while the gold is being dissolved. This assures a rapid interface between the carbon and the gold loaded cyanide solution.  Granular, hard carbon is used, in the size range of 10-16 mesh. The carbon is then removed by screening, across a carbon screen, allowing the liquid and finely ground ore (-100 mesh) to pass through easily, and retaining the carbon on the screen.  The pregnant cyanide solution flows through the carbon columns, which are generally situated in step fashion, so that the overflow from the highest column will gravity flow to the next column, alleviating the requirement for pumping. The gold adsorbs onto the surface of the carbon. The loaded carbon is periodically removed from the columns, and sent to the stripping circuit.

The gold obtained in the Merrill Crowe process is subjected to operations of drying kiln retort at 650 ° C. Finally, the obtained product undergoes a process of smelting electric arc furnace to 1,200º C for the Dore, a bar made of a mixture of gold and silver. After recovery, the contained metal is smelted and cast as 400oz doré bars containing 75% gold and 20% silver. The UK-based refiner Johnson Matthey is responsible for shipping the bars.