Gold ore mining process and processing equipments

Gold Mining Details

Brief Introduction of Gold Ore Processing Flow

NO．	Equipment	NO．	Equipment	NO．	Equipment
1	Gyratory crusher	2	Conveyer The major coveying equipment for gold ore transport.	3	Stockpile
4	Lime feed system The major feeding machine for gold primary crushing.	5	Primary cyclones	6	SAG mill
7	Ball Mill The major grinding equipment for gold grinding.	8	Secondary cyclone	9	Trash screen The major screening equipment for gold ore screening.
10	Leach and CIL tanks	11	Carbon safety screen	12	Tailings dam
13	Hydrochloric acid	14	Loaded-carbon recovery screen	15	Acid wash and water rinse tank
16	Stripping column	17	Sodium cyanide	18	Carbon regeneration kiln
19	Stripped carbon	20	Eluate tank	21	Electrowining cells
22	Electrorefining cells	23	Remelt furnace	24	Dore bullion bar

Primary, secondary crushing, and grinding of gold ore to reduce the ore down to a fine particle size

During gold ore processing, gold ore is stockpiled at the gold processing plant. It is firstly fed into a hopper with a loader, and then is conveyed by belt conveyor to jaw crusher for primary crushing and then to cone crusher for secondary crushing while lime is adding into it to raise the pH of the ore. After primary crushing, the gold ore is fed into the SAG mill along with water, and then convoyed to ball mill for further grinding which reduces the gold ore to slurry.

The slurry fine enough passes through the trammel to primary hydrocyclone which uses centrifugal and gravitational forces to classify the rock particles according their size. The fine particles will be pumped to a secondary hydrocyclone, while the larger ones return to the SAG mill for regrinding.

80% of the gold ore particles of the obtained slurry after the process are less than 70 microns in size, which is required for gold liberation. It passes through the thickener to remove some of the water, and the moves into the leaching circuit.

Leaching and absorption of ground ore slurry to extract the precious metals from the rock

The slurry of ground ore and lime passes into a series of leach tanks added of sodium cyanide solution which dissolves gold. The obtained slurry moves into a series of carbon absorption tanks. Carbon is heated to 600 degrees C and fed through the tanks to remove the gold from the solution.

The tailings – the barren slurry out the tanks, is pumped to the tailings storage dam. The carbon which has absorbed gold is pumped to the eluate tank to wash off the gold with superheated water. The washed solution, namely pregnant eluate, is passed to the electrowinning circuit.

Electrowinning and electrorefining circuit for precious metals recovery to produce doré bullion bars

The pregnant eluate moves to a series of electrowining cells which contain cathodes to attract gold from the slurry. The cathodes are then rinsed, yielding a muddy sludge. The powder obtained after drying the muddy sludge is mixed with fluxes and put into the remelt furnace. After several hours of heating, the molten material is poured into a cascade of moulds to produce doré bullion bars.