Prominer maintains a team of senior gold processing engineers with expertise and global experience. These gold professionals are specifically in gold processing through various beneficiation technologies, for gold ore of different characteristics, such as flotation, cyanide leaching, gravity separation, etc., to achieve the processing plant of optimal and cost-efficient process designs.
Prominer has established strategic relationships with equipment suppliers and commercial laboratories, so that together with advanced technology we deliver the best in gold processing plants.
Gold Processing Plant:
Based on abundant experiences on gold mining project, Prominer helps clients to get higher yield & recovery rate with lower running cost and pays more attention on environmental protection. Prominer supplies customized solution for different types of gold ore. General processing technologies for gold ore are summarized as below:
I. Physical Gold Processing Technology:
II. Chemical Gold Processing Technology:
Carbon in Leaching (CIL)
Carbon in Pulp (CIP)
Heap Leaching (Dump leaching)
Desorption Electrolysis Process
For alluvial gold, also called sand gold, gravel gold, placer gold or river gold, gravity separation is suitable. This type of gold contains mainly free gold blended with the sand. Under this circumstance, the technology is to wash away the mud and sieve out the big size stone first with the trommel screen, and then using centrifugal concentrator, shaking table as well as gold carpet to separate the free gold from the stone sands.
Flotation process are widely used for improving the sulfide type gold ore grade. The ore pulp slurry is pumped to flotation cells for extracting. The flotation cells are divided into several parts: roughing, concentration and scavenging (the exact numbers of stages for each part should be decided by test work to reach the best recovery), and with the use of frothing agent and collecting agent, the gold concentrate will be collected. The flotation concentrates can be sold to the smelting factory based on normal trade or processing agreement. The flotation concentrates go to cyanide process or calcination process (if there is arsenic together with the concentrate) and further process to get pure gold in the smelting factory. During this process, the silver & copper can also be collected.
CIL or CIP
CIL is mainly for processing the oxide type gold ore if the recovery rate is not high or much gold is still left by using ﬂotation and/ or gravity circuits. Slurry, containing uncovered gold from primary circuits, is pumped directly to the thickener to adjust the slurry density. Then it is pumped to leaching plant and dissolved in aerated sodium cyanide solution. The solubilized gold is simultaneously adsorbed directly into coarse granules of activated carbon, and it is called Carbon-In-Leaching process (CIL).
Heap leaching is always the first choice to process low grade ore easy to leaching. Based on the leaching test, the gold ore will be crushed to the determined particle size and then sent to the dump area. If the content of clay and solid is high, to improve the leaching efficiency, the agglomeration shall be considered. By using the cement, lime and cyanide solution, the small particles would be stuck to big lumps. It makes the cyanide solution much easier penetrating and heap more stable. After sufficient leaching, the pregnant solution will be pumped to the carbon adsorption column for catching the free gold. The barren liquid will be pumped to the cyanide solution pond for recycle usage.
Electrowinning & Smelting
The loaded carbon is treated at high temperature to elute the adsorbed gold into the solution once again. The gold-rich eluate is fed into an electrowinning circuit where gold and other metals are plated onto cathodes of steel wool. The loaded steel wool is pretreated by calcination before mixing with ﬂuxes and melting. Finally, the melt is poured into a cascade of molds where gold is separated from the slag to gold bullion.