Heap Characterization

HGS has developed characterization techniques that provide direct measurement of key physical, hydraulic and chemical parameters along the profile of a heap. Our techniques are efficient and non-invasive and can be implemented without the need of traffic of heavy-equipment on the heap surface. Current tools include:

  • Penetration profiles - A quick approach to determine the suitability of a heap profile for a leaching process. This approach provides a qualitative measure of the ore strength and/or degree of densification of the ore.
  • Surface Permeability Measurements - Uses standard and state-of-the-art tools and measuring techniques to determine the ability of the ore surface to accept leaching solution. Ideal to assess the impact of alternative stacking procedures and traffic on the ore surface.
  • Moisture Content profiles - Relies on state-of-the-art electric resistivity techniques and laboratory calibration methods to generate a detailed estimate of the moisture distribution below the surface of the heap.
  • Permeability profiles - A recently developed tool that permits the detailed characterization of the permeability of the ore, the most critical hydrodynamic parameter for the design of a percolation leaching process. Application of this technique is specially suited to collect a large number of measurement to define the heterogeneity of the ore permeability which in turns provides the necessary basis to select an optimal irrigation scheme.
  • Close-Spacing Sampling - Relies on high-density sampling and geochemical characterization techniques to define the chemical profile on the subsurface of the heap.
  • Electrical Resistivity Imaging - Uses advanced electrical resistivity techniques to investigate subsurface structures within the heap arising from solution-ore contact. In combination with HGS' laboratory measurements of the relationship between electric resistivity and moisture content, ER measurements provide a rapid diagnosis of wetting uniformity a key driver of the leaching process at the industrial scale.

Secondary Au recovery Project