Introduction
The shaking table is one of the main equipment for gravity separation. It is widely used in the separation of tungsten, tin, tantalum, niobium, gold and other rare and precious metal ores. It can be used for roughing, concentrating, sweeping and other operations to separate coarse sand (2-0.5mm), fine sand (0.5-0.074mm), ore mud (-0.074) and other different particle sizes. It can also be used to separate iron, manganese ore and coal. When processing ores such as tungsten and tin, the effective recovery particle size range of the 6-S fiberglass shaking table is 2-0.22 mm.
Definition
The ore dressing shaking table can make the ore particles move in different directions according to their density and particle size, and fan out along the diagonal from the feed trough, and discharge along the edge of the bed in turn. The discharge line is very long and can accurately produce a variety of products of different qualities, such as concentrate, sub-concentrate, medium concentrate and tailings.
The ore dressing shaker is used as a re-selection equipment and has been widely used in the separation of minerals such as placer gold, mainly for gold or coal selection.
Ore dressing shaker classification: ore sand ore dressing shaker, ore mud ore dressing shaker, FRP ore dressing shaker, 6-S ore dressing shaker, LS ore dressing shaker, etc.
Influencing factors
Asymmetry of shaking table motion
It has a great influence on the selective transport of ore particles in the longitudinal direction and the looseness of the bed. Appropriate asymmetry requires both good selective transport performance and sufficient looseness of the bed. For coarse-grained materials that are difficult to loosen and easier to transport, the asymmetry can be smaller, and for fine-grained materials that are easier to loosen but more difficult to move, the asymmetry is larger.
Stroke and stroke frequency
They directly determine the speed and acceleration of the bed surface. Therefore, they also have a great influence on the loose stratification and selective transport of the bed. The optimal stroke and stroke frequency should make the bed well separated and stratified, and have strong selective transport capacity. For coarse-grained materials, selection operations and heavy loads, a large stroke and a small number of strokes are used. The general stroke is 16-30 mm and the number of strokes is 200-250 times/min. For fine-grained materials, roughing operations and light loads, a small stroke and a large number of strokes are used. The general stroke is 8-10 mm and the number of strokes is 250-300 times/min.
Water volume and slope
They both affect the lateral water flow velocity and water layer thickness on the bed surface, and determine the speed of lateral transportation of ore particles and the size of the cleaning effect. Therefore, they are factors that are often adjusted during operation. Increasing the slope can reduce the amount of water, and vice versa. Increasing the amount of water and reducing the slope can make the water layer thicker. During operation, the amount of water and the slope must be well matched. For coarse-grained materials, difficult-to-select materials and selection operations, a larger flow rate and a thicker water layer are required, and a small slope and a large water system should be adopted. For fine-grained materials, easy-to-select materials or roughing operations, a larger flow rate and a thinner water layer are required, and a large slope and a small water system should be adopted. The inclination angle is generally 0-10 degrees, and the water volume is 20-50 liters/minute.
Feed volume and feed concentration
Both affect the stratification and transportation speed. Too large a feed volume will make the bed too thick, the stratification worse, and the transportation speed increase, thereby increasing the tailings grade and reducing the recovery rate. Too small a feed volume will greatly reduce the processing capacity. If the concentration is too high, sand piles will appear, and if the concentration is too low, grooving may occur. The feed volume and concentration should be well matched. The principle is to select the best feed concentration within the allowable feed volume load range. Generally, the feed concentration is 15%-25%, with a high value for coarse particles and a low value for fine particles. When processing sand ore above 0.2 mm, the production capacity is 0.7-2.3 tons/unit-hour, and when processing fine particles below 0.2 mm, the production capacity is 0.2-0.5 tons/unit-hour.
Feed particle size and shape
They affect the accuracy of sorting by density. For this reason, grading, desludging and de-coarsening before selection are very necessary. Round and heavy mineral particles not only interfere with the sorting of fine particles, but also easily lose in the tailings. If the coarse and round ones are gangue, it is beneficial to sorting. Fine mineral mud is not easy to settle and easily loses in the tailings. The graded materials have uniform particle size, easy operation and adjustment, and reasonable load distribution of coarse and fine shaking tables, which is conducive to improving production capacity.
