At present, countries around the world are gradually emerging from covid-19, the economy is in the recovery phase, and economic prosperity will drive the consumption of gold. As the role of gold as a defensive asset is re-recognized, the gold spot market will be very optimistic in the future.
Markets insider shows that the international gold ore price has shown a sharp upward trend in the past 5 years. This year (2021) the gold is reported at more than $1,700 per ounce.
Africa is the world's 3rd largest gold producer
With the gold rush, gold has been enthusiastically sought after by bankers, mining companies, manual absenteeism and minor absenteeism.
African gold mining traditionally is dominated by South Africa and has shifted its focus to countries such as Ghana, Mali, and Burkina Faso.
At present, Ghana is one of the world's leading gold producers and the largest producer in Africa. In 2020, it produced about 150 metric tons of gold.
South Africa's gold mine production accounts for 4.2% of the world's precious metal production. South Deep is the largest gold mine in the world. Mponeng Mine is the deepest gold mine in the world. And for TauTona Mine, it is home to the world's deepest mining operations, rivaled only by Mponeng Mine.
Gold processing plants in Africa
Do you know which types of gold ore are most welcomed by Africans? Alluvial gold, placer mine, rock gold, gold sulfide ore, and oxidized gold ore can be processed into the valuable gold bars, jewelry, etc.
So, how to get the most gold at a lower cost?
1. Nigeria 80 TPH alluvial gold & placer mine processing plant
Nigeria gold processing plant processed the mud-containing alluvial gold and placer gold ore, mostly in the form of particles. Its production capacity is 80 t/h. The feed size is 0-200 mm, and the placer gold size is 0-3 mm.
The gold processing plant uses the gravity separation method, and the equipment is configured as a trommel screen + jigger + shaking table.Gold processing steps:
1. Wet crushing and washing
Large raw gold ore is fed by a vibrating feeder and enters a trommel screen. The high-pressure water in the drum crushes and washes the ore containing clay and silt. Large coarse ore is discharged from the tail of screen, and fine ore enters a jigger.
The coarse-grained grade without gold and the fine-grained grade with more gold is sent to a jigger for rough sorting and clear concentration. The useful concentrate is obtained from the tailings of the jigger.
3. Extraction of gold
Then it is concentrated by a shaking table to obtain the high-grade gold concentrate.
- Trommel screen can process the soil-containing alluvial gold, placer gold and river mud gold. It is economical, simple and efficient while allowing rapid and large-volume processing.
- Jigger is a gravity beneficiation equipment. As the gold density is relatively high (19.3 grams per cubic centimeter), and the density difference between gold and gangue is large, most useful minerals can be recovered by the jigger.
- Shaking Table is very effective. The separation efficiency is higher than other fine-grain gravity separation equipment. It can separate coarse sand (2-0.5mm), fine sand (0.5-0.074mm), and slime (-0.074mm) of different particle sizes. It concentrates a large amount of gold ore at a time, and the gold concentrate obtained is highly enriched.
2. South Africa 600 TPD low-grade rock gold processing plant
A gold processing plant in South Africa processes rock gold, which is a kind of sulfide gold mine with complex composition. Its production capacity is 6000 tons/day. The feed size is 100 mm.
The plant usesflotation method. The equipment is configured as a jaw crusher+ cone crusher + vibrating screen + ball mill + spiral classifier + flotation machine. The final gold recovery rate is about 70%.Gold processing steps:
1. Two-stage crushing
The crushed gold ore is screened by a vibrating screen.
After screening, the gold ore enters a ball mill for grinding. The grinding fineness is required to be above 180 mesh.
The ground gold ore enters a classifier. Then the qualified gold ore enters the flotation machine, while the unqualified ore continues to be ground.
Add reagents to the flotation machine and mix them. Then a high-grade gold concentrate is obtained.
- When the composition of gold ore is complex and it is difficult to hand by the gravity separation, flotation is the best option, but a large amount of capital is required.
- During flotation, useful minerals accumulate on the top of flotation machine in the form of foam. By scraping off these foams, the gold concentrate is obtained, while the useless minerals fall into the bottom of tank and are discarded as tailings.
3. Tanzania 10 TPH rock gold processing plant
The material processed by the Tanzanian gold processing plant is rock gold, which is a kind of oxidized gold ore. The gold particle size of the rock is very fine. The production capacity is 10 tons/hour. The feed size is 0-125 mm.
The plant uses the gravity method. The equipment is configured as a jaw crusher+ hammer crusher + ball mill + shaking table. The result is that the free gold recovery rate is 97%. This plant is very popular with African gold miners, as it has the lowest cost and fastest return compared with the flotation plant.Gold processing steps:
Next, the gold ore is fed into a ball mill to grind into the gold powder, so that the free gold is completely freed.
3. Extraction of gold
Finally, the gold ore is sent to a shaking table. After being recovered and enriched by a shaking table, the gold concentrate is obtained.
Besides, the most popular gold extraction methods also include Gold Cyanide Process, Carbon Pulp Gold Extraction Process, and Resin Pulp Gold Extraction Process. They are all based on the ground gold ore.
- Gold Cyanide Process: The ground goldmines are contacted with a cyanide-containing solution to separate the solids from the clear solution; the precipitation method is used to recover gold from the zinc powder solution. Metso provides a world-leading process of gold cyanidation.
- Carbon Pulp Gold Extraction Process (CIP/CIL): This process uses activated carbon for gold recovery. That is, put the activated coconut carbon into the cyanide ore slurry to adsorb the dissolved gold. Then gold is extracted. Mesto has a mature CIP/CIL technology as well.
- Resin Pulp Gold Extraction Process: Through ion exchange resin, gold can also be extracted from ore pulp. This process causes gold to be adsorbed on solid spherical polystyrene resin beads. SGS is a famous Resin Pulp Gold Extraction manufacturer. In 2017, it was named one of the best multinational companies by Forbes.
Africa has rich gold mine resources. To obtain the most gold at a lower cost, it is essential to establish an efficient gold processing plant.
Fote Machinery has more than 40 years of experience in gold processing equipment. It has successfully helped South Africa, Nigeria, Zambia, Sudan, Ghana, Kenya, and other African countries to establish large, medium, or small gold processing plants. All machines can be customized according to your needs.