Spraying Method and Environment on Heap Leaching Process of Gold Ore

01Spraying method for heap leaching of gold ore

The choice of spraying method will affect the cyanide leaching efficiency, the uniformity of the distribution of the leaching solution on the ore pile, and the atomization loss of the leaching solution. In actual production, the ore dressing plant adopts intermittent spraying, which can help replenish the oxygen consumed in the ore pile and improve the leaching efficiency. Generally, you can choose to spray for one hour and stop for 0.5 hours. During the spraying process, you need to pay attention to the uniformity of the spraying and leave no dead corners. If there is a gap, you need to spray manually. In order to reduce the consumption of reagents, it is necessary to reduce the generation of atomization as much as possible during the spraying process, pay attention to the changes in wind direction and wind force in time, and prevent the loss of spraying. During the spraying, check whether there is ditch flow, overflow, and water accumulation at any time, and take measures to solve it in time.

02Spraying intensity of gold ore heap leaching

Spraying intensity refers to the amount of leaching liquid sprayed on a certain amount of ore or per square meter of the top surface of the heap in a unit time. Increasing the spraying intensity will accelerate the circulation of the leaching liquid, thereby increasing the leaching speed of gold. However, if the spraying intensity is too high, it will accelerate the leaching of impurities in the heap, thereby reducing the gold grade in the leaching liquid and increasing the difficulty of handling the gold-containing leaching liquid. If the spraying intensity is too low, the leaching operation cycle will be extended. The spraying intensity is related to the permeability of the heap, the size of the heap, and the impurity content in the ore. If the permeability of the heap is poor, or the impurity content is high, or the heap size is large, the spraying intensity should be controlled at a lower value, otherwise it should be controlled at a higher value.

03Effect of temperature on heap leaching of gold ore

Temperature has a great influence on gold ore heap leaching. When the temperature is low, the leaching rate of gold decreases, especially when the temperature is below ten degrees, the leaching rate of gold will be greatly slowed down. On the contrary, the higher the temperature, the faster the leaching rate of gold. However, it should not be too high, otherwise it will reduce the solubility of oxygen in the leaching solution and accelerate the hydrolysis of cyanide, consuming cyanide. In the process of heap leaching of gold ore, it is generally not necessary to heat the leaching solution, unless it is in a cold area. In order to prevent freezing and appropriately extend the heap leaching operation time, it is necessary to consider technical feasibility and economic rationality.

04Effect of weather on heap leaching of gold ore

Different weather conditions will have different impacts on heap leaching operations. Rainy seasons and regions will increase the amount of leaching liquid, reduce the pH value and cyanide concentration of the leaching liquid and the grade of gold. When it is in a dry season or a rainy area, it will cause the loss of spraying liquid and gold. In areas with a long freezing period, the suitable heap leaching period is short. In summary, the impact of weather conditions on gold ore heap leaching production needs to be considered.

To sum up, the efficiency and effect of the gold ore heap leaching process are multiplely affected by the spray method, spray intensity and environmental conditions. In actual production, rational selection of spray parameters based on the characteristics of the ore pile and local climatic conditions, and taking adaptive measures in special environments such as cold, drought or rain, can significantly improve the gold extraction effect of the heap leaching process and reduce the cost. This provides important support for the cost-effective mining of gold deposits.