1. Comminution Equipment: Size Reduction & Liberation
In hard-rock gold mining, gold particles are encapsulated within tough quartz veins or sulfide ore matrixes. Comminution reduces run-of-mine (ROM) ore down to liberated microscopic sizes, making particles accessible for gravity separation or leaching.
- Primary Jaw Crushers: Heavy-duty, heavy-pit jaw crushers serve as the primary reduction stage, crushing large ROM boulders (up to 500–800 mm) down to 50–100 mm feed sizes.
- Secondary & Tertiary Cone Crushers: Utilizing hydraulic adjustment and high-speed crushing cavities, cone crushers further reduce primary-crushed ore down to a uniform 10–20 mm feed, ideal for grinding mills.
- Industrial Ball Mills & SAG Mills: Grinding is the heart of hard-rock liberation. Tumbling wet ball mills loaded with high-chromium forged steel balls grind crushed rock into fine slurry (typically reaching 74 microns / -200 mesh).
2. Washing & Pre-Screening Equipment
For alluvial (placer) deposits and clay-heavy oxide ores, high-energy comminution is unnecessary. Instead, specialized washing and screening equipment liberates gold from mud, silt, and gravel matrices:
| Equipment Type | Core Mechanism | Ideal Ore Type |
|---|---|---|
| Rotary Scrubber | High-torque tumbling cylinder with heavy internal lifters and water jets | High-clay, sticky mud, and compacted laterite deposits |
| Gold Trommel Screen | Revolving mesh cylinder with internal high-pressure spray bars | Clean river gravel, sand, and low-clay placer gold deposits |
| Vibrating Screen & Grizzly | High-frequency linear/inclined deck screening for size classification | Coarse boulder scalping and dry circuit screening |
3. Gravity Separation Equipment: Free Gold Recovery
Density-based physical separation is the most cost-effective gold recovery method. Because gold is significantly denser than surrounding gangue minerals (specific gravity of ~19.3 vs. ~2.6 for quartz), gravity separation captures free coarse and fine gold without expensive chemical reagents.
- Centrifugal Gold Concentrators: Utilizing high centrifugal acceleration (60G to 100G), centrifugal units (such as STLB or Knelson-type concentrators) force ultra-fine free gold (-200 mesh / <74 microns) out of slurry suspension, achieving up to 95%+ recovery.
- Pulsating Sluice Boxes & Mineral Jigs: Hydraulic jigs and pulsating sluice boxes prevent bed compaction, making them exceptional for capturing coarse-to-medium gold nuggets in high-volume throughput circuits.
- Shaking Tables (6-S): Featuring sloped decks with riffles subjected to reciprocating motion, shaking tables perform fine-grade dressing of gravity concentrates, yielding clean, high-grade gold dust ready for direct furnace smelting.
4. Chemical Extraction & Leaching Systems
When gold particles are sub-microscopic, encapsulated in sulfides, or refractory, physical gravity separation must be supplemented or replaced by chemical leaching circuits:
- CIL / CIP Cyanidation Tanks: In Carbon-in-Leach (CIL) and Carbon-in-Pulp (CIP) circuits, slurry is agitated in large tanks with cyanide solution while activated carbon absorbs dissolved gold complexes for high-efficiency recovery.
- Desorption & Electrowinning Systems: High-pressure, high-temperature elution columns strip gold from loaded carbon into rich pregnant solution, where electrolytic cells deposit metallic gold onto steel wool cathodes.
- Heap Leaching Equipment: For low-grade oxide deposits, crushed ore is stacked on impermeable liners and sprayed with dilute leaching solutions over extended cycles, offering low CAPEX processing for large-scale operations.
Key Factors in Selecting the Right Flowsheet Configuration
- ✔ Alluvial / Placer Deposit: Feed Hopper → Rotary Scrubber / Trommel → Centrifugal Concentrator → Shaking Table.
- ✔ Hard-Rock Free-Milling Ore: Jaw Crusher → Cone Crusher → Ball Mill → Centrifugal Concentrator → Shaking Table.
- ✔ Hard-Rock Refractory / Fine Ore: Jaw Crusher → Ball Mill → Flotation / CIL Circuit → Electrowinning → Smelting Furnace.
Conclusion
Selecting the optimal gold processing equipment combination requires matching machine capacities directly with site geology, ore hardness, and particle size distribution. By pairing heavy-duty comminution units with high-G centrifugal gravity concentrators or chemical leaching lines, mine operators can maximize recovery, reduce operational downtime, and ensure strong project returns.
Looking for Custom Gold Processing Equipment Solutions?
Whether you require a heavy-duty Hard-Rock Crushing & Ball Mill Circuit, a high-recovery Centrifugal Gravity Plant, or a turnkey Mobile Gold Washing Unit, SBM's specialized mining engineering team is here to support your project.
Contact our specialists today to get a free customized flowsheet design, equipment selection guidance, and a factory-direct quote tailored to your target tonnage.
