What is the principle and nature of construction of Wilfley Table? Which mineral product is separated in tabling? IAS 2024, 15 Marks

Introduction:

The Wilfley Table is a type of gravity concentration equipment used for separating fine materials from a mixture based on their specific gravity. It is widely used in the mining industry for processing minerals such as tin, tungsten, gold, and silver.

Wilfley Table: Principle and Nature of Construction

Principle

• Gravity Separation: The Wilfley Table operates on the principle of gravity separation, where particles of different specific gravities are separated using a combination of gravity and lateral flowing water.
• Differential Settling: Materials are sorted by their settling rates in a flowing film of water. Denser particles settle faster and move differently than lighter ones.
• Riffles and Inclination: The riffles on the table surface and its inclination help separate heavier particles by trapping them while lighter materials are washed away.

Nature of Construction

• Table Design:
  
  • A rectangular, inclined table made of durable materials.
  • Riffles are embedded on the surface to enhance the separation process.
• Inclination and Motion:
  
  • The table is inclined along its length and slightly tilted along its width.
  • A mechanical oscillatory motion is imparted to the table, which facilitates the movement of particles.
• Feed Arrangement:
  
  • Material (slurry containing ore and water) is fed at one end of the table.
  • A uniform water flow across the surface assists in transporting lighter materials.
• Product Collection:
  
  • Heavier particles concentrate at one end (closest to riffles).
  • Lighter waste materials are washed to the far side.

Minerals Separated Using Tabling

Key Mineral Products:

• Heavy Minerals: The Wilfley Table is effective in separating heavy minerals such as:
  
  • Gold
  • Tungsten
  • Cassiterite
  • Chromite
  • Iron ores
• Lighter Gangue: Materials like quartz or feldspar, which have lower specific gravity, are separated as tailings.

Conclusion:

The Wilfley Table is a simple yet effective gravity concentration device that is widely used in the mining industry for separating fine materials based on their specific gravity. Its construction, which includes a deck with riffles and a frame, allows for efficient separation of minerals such as tin, tungsten, gold, and silver.