Heap Leach Air Injection

A feature of SVFlux™ and SVAirFlow™ Professional
(part of SVOffice™ 2009)



June 7, 2011

The following example uses SVAirFlow™ coupled with SVFlux™ to simulate heap leaching with air injection. The purpose of this example is to illustrate the distribution of pore air pressure, air density, and heap saturation in the case of air injection in a heap leaching scenario. Air injection is a commonly used practice for heap leaching scenarios where the reactions are oxygen-consumptive.

Complete details of this model may be found in the SVAirFlow™ Examples Manual and the numerical model may be examined in the distribution models under the project and model listed below:

  • Project:  Leaching
  • Model:   LeachingAirInjection

The example is a two-dimensional model of SVAirFlow™ coupled with SVFlux™. It consists of gravel, air pipe, and heap material, as illustrated in Figure 1:


Figure 1: Model geometry of leaching remediation

The boundary conditions are specified as shown in the following table:

ApplicationBoundaryBoundary Typevalueunits
SVFlux™ BCHeap topY-Flux expression0.04m^3 / hr - m^2
 Heap slopeZero flux  
 Heap bottomNo BC  
 Air pipeZero flux  
 Gravel (top)No BC  
 Gravel (bottom)Zero flux  
 Gravel (right slope)Zero flux  
 Gravel (left slope)Head pressure expression0kPa
SVAirFlow™ BCHeap topAir pressure expression0kPa
 Heap slopeAir pressure expression0kPa
 Heap bottomNo BC  
 Air pipeAir pressure expression10kPa
 Gravel (top)No BC  
 Gravel (bottom)Zero flux  
 Gravel (slope)Air pressure expression0kPa

Figures 2 and 3 show the distribution of pore air pressures. The contour for air density and water saturation is shown in Figure 4 and 5 at the time of 48 hours. The degree of heap water saturation without air injection is also provided in Figure 6 and 7.

The results show that numerical modeling can provide an excellent way to gauge air saturation and optimize heap leach design.


Figure 2: Pore-air pressure contour under the air injection at 24 hours


Figure 3: Pore-air pressure contour under the air injection at 48 hours


Figure 4: Air density contour under the air injection at 48 hours


Figure 5: Heap saturation contour under the air injection at 48 hours


Figure 6: Heap saturation distribution without air injection at 48 hours


Figure 7: Heap saturation distribution without air injection at 96 hours


For more information on this feature, feel free to contact us directly, or visit our online store to purchase SVFlux™ and SVAirFlow™.