What Factors Affect The Sorting Efficiency Of Spiral Chute?

The spiral chute mainly uses the inertial centrifugal force generated by the rotation of the spiral to separate light and heavy minerals. It is widely used in gravity separation due to its simple equipment structure, low power consumption, and large processing capacity. What are the factors that affect the separation efficiency of the spiral chute?

What factors affect the sorting efficiency of the spiral chute?

1. Spiral chute structure and performance

A. Spiral chute diameter

The spiral chute diameter has a direct impact on the processing capacity and recovery rate. Generally, the larger the spiral chute diameter, the greater the ore flow volume and flow rate, and the greater the processing capacity per unit time. The smaller the spiral chute diameter, the smaller the lower limit of the recovery particle size, and the higher the recovery rate.

B. Longitudinal inclination of spiral chute

The angle between the tangent of the spiral chute cross-section curve and the vertical axis is called the longitudinal inclination. The larger the longitudinal inclination, the faster the slurry flow rate, and the greater the centrifugal force on the material. Therefore, a small inclination is used when selecting fine-grained minerals, and a large inclination is used when selecting coarse-grained minerals. A suitable longitudinal inclination can make the slurry flow along the chute, obtain good mineral processing indicators, and improve mineral processing efficiency.

C. Horizontal inclination of spiral chute

The horizontal inclination is complementary to the vertical inclination. The horizontal inclination also affects the distribution of the slurry flow on the chute surface. The larger the horizontal inclination, the greater the water flow depth. Therefore, a small horizontal inclination is used when selecting fine-grained ore, and a large horizontal inclination is used when selecting coarse-grained ore.

D. The number of turns of the spiral chute

The number of turns of the spiral chute determines the separation distance and separation time. In actual operation, it needs to be determined according to the properties of the selected materials and the operating indicators. When the useful minerals and the gangue minerals are closely embedded, it is advisable to choose a large number of turns to extend the separation distance and time and improve the separation efficiency. However, the number of turns should not be too many, otherwise it will increase the height of the spiral chute and increase the difficulty of operation. Industrial separation mostly uses 4-6 turns of the spiral trough.

2. Feed ore properties

Appropriate feed size, shape, and density have a great influence on the separation of useful minerals and gangue minerals.

A. Mineral particle size

Usually, the upper limit of the spiral chute feeding particle size is 6mm. Muddy minerals need to be desludged and graded before feeding to prevent material blockage and affect the sorting efficiency.

B. Mineral particle shape

The shape of mineral particles will also affect the movement speed of minerals in the spiral chute. When the useful heavy minerals are mostly irregular or flaky in shape and the gangue minerals are round, the heavy minerals move slowly, which is conducive to stratification and sedimentation, reducing the grade of tailings and improving the sorting efficiency.

C. Mineral density

Since the spiral chute is mainly based on the different density differences of minerals for sorting, the greater the density difference between useful minerals and gangue minerals in the selected ore, the more conducive it is to sorting.