10 Q&A You Need To Know About Spiral Chute

If you are eager to learn more about spiral chutes, you're not alone. Numerous resources online detail how these gravity separation devices work and their various applications in different industries. The spiral chute offers an efficient solution for separating materials based on specific gravity, making it an essential piece of equipment in mining, recycling, and food processing sectors.

01. Definition of Spiral Chute

The spiral chute is a type of gravity separation equipment that utilizes inertial centrifugal forces produced by ore pulp in a spiral motion to separate light and heavy minerals effectively.

02. Separation Range of Spiral Chute

Commonly, the spiral chute is employed to separate a variety of materials including non-ferrous and ferrous metals, non-metallic minerals, rare metals, and heavy minerals in tailings, especially those with a particle size ranging from 0.3 to 0.02 mm. Typical examples include iron, tin, tungsten, tantalum, niobium, gold, coal, monazite, rutile, and zircon.

03. Principle of Spiral Chute Beneficiation

This type of beneficiation leverages gravity flow separation. The process is influenced by the water current's impact, gravity's effect on mineral particles, inertial centrifugal force, and the friction between the mineral and the chute surface. The slurry is introduced into a sloped chute, where the flow of water loosens and stratifies the ore particles, allowing lighter minerals to exit the chute quickly, while heavier minerals remain or exit slowly from the lower part.

04. Composition of Spiral Chute

The spiral chute consists of six primary components:

• (1) The ore divider at the top for distributing slurry.
• (2) The ore feed chute connecting the ore divider and chute.
• (3) The chute itself, made of fiberglass and formed from multiple spiral sections bolted together.
• (4) The cutting chute that connects to the discharge end of the spiral chute.
• (5) The ore receiving bucket, an annular cylinder to collect streams for subsequent operations.
• (6) The chute bracket, which provides structural support through surrounding pillars and a cross frame.

05. Classification of Spiral Chute

The spiral chute can be classified into three categories based on ore particle size:

• (1) Coarse-grained chutes for particle sizes above 2-3 mm, with a maximum capacity of 100-200 mm.
• (2) Ore sand chutes handle grain sizes of 2-3 mm.
• (3) Sludge chutes are designed for particles less than 0.074 mm.

06. Structure Parameters of Spiral Chute

Key structural parameters include:

• (1) The diameter, where larger diameters enhance processing capacity.
• (2) The cross-sectional shape, which relates to the material's particle size, usually maintaining a long to short axis ratio of 2:1 for particles smaller than 2 mm.
• (3) The pitch-diameter ratio, with around 0.73 being optimal for sorting effectiveness.
• (4) The length and turns of the spiral chute, determining the material's travel distance and required laps for effective beneficiation.

07. Advantages of Spiral Chute

Several advantages make the spiral chute a preferred choice:

• (1) Energy efficiency since it has no moving parts and consumes no power.
• (2) Space efficiency, requiring a small footprint while maintaining high processing capability.
• (3) Water-saving, as no additional flushing water is needed during separation.
• (4) Stability in separation indices, showing minimal impact from variations in ore volume, concentration, particle size, and grade.

08. Disadvantages of Spiral Chute

Despite its benefits, there are limitations:

• (1) It requires a pump to lift the slurry due to large height differences.
• (2) It has a lower concentrate grade and is best suited for roughing purposes.
• (3) It performs poorly with conjoined or flaky ores.
• (4) Adjusting operational parameters to match changing ore properties can be challenging.

09. Operation Points of Spiral Chute

Essential operation considerations include:

Suitable Ore Concentration:

The recommended ore concentration for rough separation ranges from 30%-40%, while for beneficiation, it is 40%-60%, with allowances for 5% fluctuations during processing.

Suitable Ore Volume:

The volume of feed directly influences the flow thickness and speed; larger volumes are preferable for coarse material separation, while fine materials require smaller volumes.

10. Development Trend of Spiral Chute

Future trends indicate:

• (1) Progress towards large-scale operations for increased processing capacity.
• (2) Enhanced efficiency in separating fine particles, particularly those smaller than 0.047 mm.
• (3) Improved recovery rates and enrichment of valuable minerals.
• (4) Focus on energy-saving and environmentally-friendly designs, requiring minimal space.
• (5) Simple operational structures ensuring ease of maintenance.

To Wrap Up

As the emphasis on energy conservation and environmental protection grows, the trend towards employing gravity separation methods for pre-selecting and recovering heavy minerals will inevitably expand. For more insights about spiral chutes, we invite you to consult our online customer service.