Gold mine beneficiation involves several processes to extract and refine gold from ore. Here’s a structured overview of the key steps and technologies used:
1. Crushing & Grinding
– Primary Crushing: Jaw crushers or gyratory crushers break down large ore chunks.
– Secondary Crushing: Cone crushers further reduce size.
– Grinding: Ball mills or SAG mills pulverize ore into fine particles for liberation.
2. Gravity Separation (For Free Gold)
– Shaking Tables, Sluices, Jigs: Separate coarse gold particles based on density differences.
– Centrifugal Concentrators (e.g., Knelson, Falcon): Enhance recovery of fine gold.
3. Flotation (For Sulfide Ores)
– Uses chemicals (collectors like xanthates) to make gold-bearing sulfide minerals hydrophobic.
– Froth flotation separates gold-bearing sulfides from waste rock.
4. Cyanidation (For Refractory & Free Gold)
– Heap Leaching: Low-grade ores are stacked and sprayed with cyanide solution.
– CIL/CIP (Carbon-in-Leach/Pulp): Activated carbon absorbs dissolved gold from cyanide solution.
– Electrowinning/Refining: Gold is stripped from carbon and smelted into doré bars.
5. Bio-Oxidation & Pressure Oxidation (For Refractory Ores)
– Used when gold is locked in sulfides (e.g., pyrite). Microbes or high-pressure/temperature break down sulfides before cyanidation.
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6. Tailings Management & Environmental Controls
– Cyanide detoxification (e.g., SO₂/air process). 
– Dry stacking or filtered tailings to reduce environmental impact.
Emerging Technologies
– Sensor-Based Sorting (XRT, Laser): Pre-concentrate ore before processing.
– Thiosulfate Leaching: Alternative to cyanide for eco-friendly extraction.
Would you like details on a specific stage or type of gold deposit?
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