Ore Dressing Shaking Table
A shaking table is an important device that uses gravity, friction, and inertial forces to separate minerals based on differences in density, particle size, and shape. It is widely used in mineral processing flowsheets for metallic ores, non-metallic ores, and coal.
1. Working Principle
Stratification Caused by Bed Motion
The shaking table surface is inclined longitudinally at a certain angle and driven by a transmission mechanism to perform reciprocating asymmetric motion: slow forward speed and fast backward speed.
As particles move with the table surface, they are affected by friction and inertia, leading to stratification: heavy minerals with high density and appropriate size tend to move toward the lower layer of the bed and advance forward, while light minerals remain in the upper layer and are carried backward or sideways by transverse water flow.
Water Flow and Riffles Enhance Separation
Wash water is fed along the table surface in a transverse direction, further washing away light minerals and helping heavy minerals form enrichment zones on the bed.
Riffles (or grooves) on the table surface disrupt the uniformity of the particle layer, increase looseness, and facilitate separation of particles with different densities.
Product Zoning and Collection
The table surface is divided longitudinally into concentrate end, middling end, and tailings end; transversely, products are concentrated in different positions according to their density and size, and are separately discharged by adjusting splitters.
2. Main Structure and Components
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Table Surface: Usually made of wood or fiberglass, with riffles or grooves on the surface, determining separation precision and processing capacity.
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Frame and Support: Supports the table surface and maintains its inclination, ensuring smooth movement.
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Transmission Mechanism: Mostly eccentric connecting rod type, converting motor rotation into reciprocating asymmetric motion of the table.
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Feed System: Includes feed troughs and water troughs, controlling pulp concentration, flow rate, and distribution uniformity.
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Launder and Splitters: Used to separate and collect different products such as concentrate, middling, and tailings.
3. Classification and Application Features
By Purpose and Processed Material
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Coarse Sand Shaking Table: Treats coarser fractions (e.g., 2–0.5 mm), with higher riffles, suitable for recovery of heavy minerals like tungsten and tin.
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Fine Sand Shaking Table: Processes medium-size fractions (e.g., 0.5–0.074 mm), most widely applied.
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Slime Shaking Table: Handles fine particles and slimes (<0.074 mm), with smoother surface, smaller stroke, and higher frequency.
By Drive Method
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Mechanical Shaking Table: Driven by cranks, connecting rods, cams, etc.; mature and reliable structure.
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Electromagnetic/Vibrating Shaking Table: Uses electromagnetic vibrators instead of mechanical drive; wide range of adjustable parameters, easy automation.
Typical Applications
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Metallic Ores: Gravity concentration of tungsten, tin, tantalum-niobium, gold, silver, etc.
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Ferrous Metals: Pre-concentration or cleaning of hematite, manganese ore, etc.
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Non-Metallic Ores: Desulfurization and deashing of coal; separation of feldspar, quartz, fluorite, etc., by density and size.
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Tailings Re-treatment: Recovery of valuable fine-grained minerals from old tailings.
4. Technical Characteristics
Advantages
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High separation precision; can simultaneously separate by density, size, and shape.
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Multiple products (concentrate, middling, tailings) obtained in one operation.
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Strong adaptability; capable of treating coarse to very fine particles.
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Simple structure, easy operation and maintenance, relatively low investment and upkeep costs.
Limitations
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Low unit area processing capacity, large floor space required.
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Sensitive to fluctuations in feed concentration, size distribution, and water quality; requires stable operating conditions.
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High slime content can cause coverage between particles, reducing separation efficiency.
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