The rational selection of placer gold beneficiation equipment directly impacts the economic benefits of placer gold mining. The placer gold beneficiation process typically includes three stages: classification, gravity concentration, and cleaning/purification. This article will briefly introduce the core equipment in the placer gold beneficiation process flow and their working principles.
I. Pre-treatment Equipment for Placer Gold Ore - Trommel Screen
The first step in the placer gold beneficiation process is pre-treatment using a Trommel Screen. The rotating drum of the trommel screen effectively separates oversized gravel and clay impurities, significantly improving the efficiency of subsequent gravity concentration stages. The screen mesh design ensures that ore material of suitable particle size proceeds to the next stage.
II. Roughing and Concentration for Placer Gold - Jig Machine
The screened material is then processed by a Jig Machine. Utilizing the principle of vertical alternating water flow, the jig machine causes ore particles to stratify naturally by density on the screen plate: high-density gold particles settle to form the concentrate, while lighter gangue is carried away by the water flow. The jig machine, known for its large processing capacity and high recovery rate, is the core equipment for the roughing and concentration of placer gold.
III. Fine Gold Recovery - Vibrating Sluice Box
The Vibrating Sluice Box is particularly effective for recovering fine gold particles from placer gold ore. This improved type of sluice combines mechanical vibration with water flow scouring to efficiently recover fine gold particles remaining in the jig machine's tailings. The vibrating water film generated makes it especially suitable for processing clayey placer gold sand. It is also simple to maintain and easy to operate.
IV. Micro-fine Gold Recovery - Centrifugal Concentrator (Knelson Concentrator)
For micro-fine gold particles (-0.074mm) that are difficult to recover using traditional equipment, the Centrifugal Concentrator offers unique advantages. By generating a centrifugal force field of 200-300 G, it forces micro-fine gold particles to concentrate strongly on the inner wall of the rotating bowl. The centrifugal concentrator can increase the overall recovery rate of placer gold by 15-20%.
V. Placer Gold Concentrate Purification - Shaking Table
Concentrate purification for placer gold can be achieved using a Gold Concentrating Shaking Table. Its asymmetric reciprocating motion, combined with specially designed riffles on the deck, can upgrade the concentrate grade by three to four times or more. The shaking table is a key piece of equipment for producing high-grade concentrate.
How to Select Placer Gold Beneficiation Equipment?
Match Processing Capacity: Select equipment models appropriately based on the scale of the processing capacity.
Adapt to Ore Characteristics: Make targeted selections for different ore types such as sticky placer gold ore or lateritic placer gold ore.
Consider Ore Particle Size and Gold Dissemination Fineness: Ensure the processing particle size range of each piece of equipment meets the requirements.