In gold ore dressing industry, there are not too much beneficiation methods used because of the stable property of gold ore itself. Gravity separation and cyaniding-leaching are generally used in actual dressing operation. Here, we will focus on gravity separating method. Placer gold ore exists in monomeric form as a gold element and native gold with large density. It is most efficient and economical to separate Placer gold ore with gravity separating method.
With little-complicated principles, the gravity separating equipment has simple structures. In addition to the normal placer gold ore separating equipment like various jigs and shaking tables, there are some other gravity separating equipment for placer gold ore, represented by chutes, I chutes, pulsating sluice box, etc. Thereinto, chutes are usually fixed chutes and can be divided into big chutes and small chute. With no need of power, little cost and simple operation, this kind of placer gold ore separating machine are very effectual to recover coarse particles bigger than 0.2 mm. However, it works discontinuously, with little recovery rate of fine gold particles and heavy labor intensity.
When it comes to cyaniding and leaching method, leaching tank and collecting devices are commonly used for processing placer gold ore. The representative products are single-impeller agitation tank and double-impeller agitation tank. The single-impeller Placer gold ore equipment, also called axial-flow type leaching agitation tank, is designed and manufactured by China Central Engineering Institute for Nonferrous Metallurgical Industries. It is suitable for the gold leaching-absorption and other operation, usually with relatively bigger density, higher viscosity, faster settling velocity, -200 mess ore particles more than 85% and slurry density less than 45%.