Technical conditions for dripping leaching and spray leachin
2020-08-10 09:25Introduction：Technical conditions for dripping leaching and spray leaching In recent years, the droplet irrigation equipment used in agricultural water supply has been popularized in the United States as dripping equipment for heap leaching of gold dep
Technical conditions for dripping leaching and spray leaching
In recent years, the droplet irrigation equipment used in agricultural water supply has been popularized in the United States as dripping equipment for heap leaching of gold deposits, which is called trickle leaching. The main pipe shall be 150 millimetres in diameter and shall be connected at 90 degrees of angle to the drop pipe of 12 millimetres in diameter along the main pipe every 0.9 metres, and shall be fitted with a droplet emitter at every 0.8 metre long along the dripping pipe, Droplets emitted from droplet emitters fall from a height of 250 mm, much lower than the spray height of ordinary sprinklers, so the loss of evaporation and floatation of the solution is small. If the cold season occurs, the heap leaching can be carried out by embedding the dripping pipe into the depth of 0.6 ~ 0. 9 meters above the ore heap, which will not freeze, and the heap leaching can continue. The experiment also shows that the scaling phenomenon of calcium carbonate can be greatly reduced by using dripping device.The technical conditions for spray or trickle leaching include the following:
1. Granularity of ore entering reactor : for highly oxidized, porous, fragile ores, the ore size can be controlled below -50 mm. For general oxidized ores, they may be controlled below -25 mm, and for dense ores, the ore size entering the reactor should be controlled below -15 mm or -10 mm;
2. In the leaching solution, the concentration of sodium cyanide should be controlled between 0.03% and 0.1%, the initial stage of leaching can be controlled in the high limit, and the final stage of leaching can be controlled at the bottom limit;
3. The pH value of the leaching solution should be controlled between 10~12;
4. The leaching strength of leachate is generally controlled at 20-25 L / (m2 ·h), and the drop strength is 12 L /( m2·h). When the ore has poor permeability or high impurity content, or when the ore heap is large, the spray or droplet strength may be low, whereas, the high value can be obtained;
5. The leachate should be sprayed intermittently so that the ore heap can be oxygenated for 1 hour spraying and stop for half an hour.
