Ultrasonic vibrator tray processes

DETAILED DESCRIPTION The techniques of this invention provide unexpectedly effective and economic methods and apparatus for beneficiating such crushed or granulated ores.
In the case of coal gob piles and coal slurry ponds, they achieve surprisingly efficient recovery of valuable coal, while also improving the characteristics of the residue for densely packed back-filling of coal mining pits, open or underground, and filling the voids of the underground excavations to prevent subsidence, and reducing the settling times for ponds and settling basins to produce clarified wash water for recycling or other uses.
These multiple advantages are achieved through a novel technique by which the ore is mixed with approximately up to about thirty-five percent solids by weight and sixty-five percent by weight of water to create a slurry, which is delivered in a fast-flowing shallow sheet descending along an inclined thin sheet metal vibrator tray actuated by a plurality of ultrasonic transducers to produce standing wave patterns of ultrasonic vibrations.
The vibrator tray is preferably suspended by flexible cables to maximize its flexural freedom to vibrate and undulate, and the vigorous vibratory energy thus imparted to the advancing slurry sheet produces rapid de-agglomeration and separation of ore from ash and other residues.
A second tray can be superimposed on the first tray to permit reflection of the ultrasonic vibrations.
Differing densities of the different types of particles reinforce the separation.
Settling, centrifugal separators or screens achieve nearly complete recovery of the valuable coal fines.
The same novel technique can be used to separate gold and other valuable minerals from crushed ore, with equally successful results.
In using the process of the present invention on the valuable mineral ore, minerals not soluble in water tend to cling to the valuable mineral particles.
Various chemicals such as mercury, thiourea, cyanide or bromide can be added to the process to obtain better separation of the valuable mineral particles from the ore using amalgamation, leaching or agglomeration techniques