By Deborah Johnston, PE

Are you considering adding solution handling capacity to your heap leach operations? If your reasons for wanting to add a carbon-in-column plant are for primary gold recovery or as a scavenger circuit to pull ounces from re-circulation, your next question might be, “Would a vertical design make more sense?”

Cascading columns (also known as gravity) Carbon-in-Column (CIC) Plants are one of the most common and proven engineering solutions for processing solution from heap leach pads. They consist of large-diameter columns that are filled with activated carbon. The pregnant solution flows through the carbon columns, generally in a step-down arrangement so that the overflow from the highest elevation column will flow to the next column. The gold absorbs onto the surface of the carbon. The loaded carbon is periodically removed from the columns and sent for stripping.

With at least four Vertical Carbon-in-Carbon (VCIC) Plants commissioned in the past two years in Nevada alone, a vertical plant design is something you might want to consider. The advantages of the vertical column approach include the following:

  • Smaller footprint.
  • Reduced amount of valving between stages.
  • Reduced fabrication costs.
  • Between 20 and 30 percent lower installation costs.

If your operation is constrained by any of the issues above, “going vertical” might be the way to go.