Low cost and high yields of gold ore dressing technology

A dilute cyanide-water solution is pumped through the series of plastic hose with sprays or drip emitters placed throughout the pile, and solution runs through the leach, dissolving gold. Pregnant solution (gold bearing solution) runs from the pile in the drainage pipes or ditches, and is collected in a series of ponds. The leach area is lined with several impermeable liners, primary and secondary liners, to prevent the possibility of any solution escaping into the ground. Monitoring wells are stratagically placed and continuously monitored to be certain that no leakage has occurred.The 1980s saw a rapid expansion in gold production from low-grade oxide deposits around the world. That expansion could not have occurred without the development of a new, low-cost method of recovering the gold. That process is called heap leaching.

Cyanidation (the actual dissolution of the gold) begins in the grinding step. Cyanide and lime solutions are introduced here, where newly liberated gold particles are constantly being polished by the grinding action and the solutions are heated by the friction. Depending on the ore and fineness of grind, from 30% to 70% of the gold may be dissolved during the grinding process. Henan Hongxing Mining Machinery Co., Ltd. is the professional manufacturer of complete sets of mining machinery, for example, coal concentrator. Welcome all of you to visit our official website.

Heap leaching avoids most of the above steps, and does not even require that a mill be built, making it a very low-cost method of processing ore. Here, broken ore is heaped onto a thick polyethylene sheet, called a liner, and then dilute cyanide solution is sprinkled on top of the heap. As the solution trickles down through the ore, the gold is dissolved. Before the heap is constructed, the polyethylene liner is laid down in such a way that the cyanide solution will drain to a central point. From here the gold-laden solution is channeled into a man-made pond.

Extracting Gold Out of Solution: Traditionally, recovering the gold from the cyanide solution was achieved by separating the gold-laden, or pregnant, solution from the barren solids present and then precipitating the gold.

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