Key Benefits

  • Robust
  • Easy to maintain
  • Cost-effective

Leaching and adsorption circuits for maximum recovery

During the leaching and adsorption process, it's important to have equipment that can guarantee you the maximum precious metals recovery. At FLSmidth we understand this and offer leaching and adsorption circuits designed not only for optimal performance but also cost-effectiveness and simplicity.

During the leaching and adsorption process, it's important to have equipment that can guarantee you the maximum precious metals recovery. At FLSmidth we understand this and offer leaching and adsorption circuits designed not only for optimal performance but also cost-effectiveness and simplicity.

 

Our adsorption circuits include the Carbon in Column (CIC) circuit, the Leach - Carbon in Pulp (CIP) circuit, and the Carbon in Leach (CIL) circuit, all have similarities, but differ when it comes to the leaching and adsorption process.

 

The CIC circuit is an adsorption-only system used to treat relatively clear pregnant solutions, such as heap leach, CCD, and pre-leach thickener overflow. The circuit utilizes upflow tanks to form an active fluidized bed of carbon to adsorb gold and silver through series of adsorption stages. The CIC circuits are commonly configured in cascade orientation, but may be supplied in vertical design to limit floor space requirements and cost. We offer our cascade CIC columns available up to 6.1 meters in diameter for flow rates up to 2,500 m3/hr per train.

 

The Leach-CIP circuit is a system comprised of separate leaching and adsorption tanks. In leaching, ore which has been ground to pulp is placed in agitated tanks with sodium cyanide solution and gold and silver is dissolved into the slurry solution. The leach may require 24 to 72 hours to complete, and after the leach is completed, the leached slurry is routed to the CIP circuit. In CIP, adsorption of gold and silver onto activated carbon is completed in agitated tanks with interstage screens used to retain the activated carbon within the tank. The tanks are configured in stages and can be configured in cascade orientation making use of gravity slurry flow or in an active carousel configuration where the slurry is effectively pump from tank to tank. Leach-CIP is effective and comprises most of the grinding circuit leach installations. While it may have a larger footprint, it promises a lower carbon inventory, smaller gold lockup, and lower carbon attrition.

 

The CIL circuit utilises combined leaching and adsorption tanks, meaning that this circuit has the capacity to complete both processes at the same time. This also means that cyanide, ore pulp, oxygen and carbon are all introduced together. In CIL, adsorption of gold and silver onto activated carbon is also completed in agitated tanks with interstage screens used to retain the activated carbon within the tank. The sizing of the tanks is calculated based on the time required to completely leach the ore, usually 24-72 hours. The tanks are configured in stages and can be configured in cascade orientation making use of gravity slurry flow or in an active carousel configuration where the slurry is effectively pump from tank to tank. It can achieve high recovery of preg-robbing ore and is known for its smaller footprint on the environment.

 

With these circuits available to you, we assure you that you’ll find a system that suits your plant's needs.

Maintainable and inexpensive metals recovery

Our three recovery circuits possess many advantages, particularly as they improve on older and highly regarded techniques of leaching and adsorption.

Proper design

Our leach and adsorption circuits are designed and supplied to exceed the specifications of your plant. From small to large systems, our designers seek to provide long-lasting circuits with careful attention made to proper residence time, agitation, slurry mixing, oxygen dispersion, eliminating short circuiting, slurry density and reagent introduction, including cyanide and pH control.

Easy to maintain
Our CIC, CIP and CIL circuits have been designed with maintainability in mind. We aim to reduce space requirements, while also making sure that equipment is easy to access.  We only use proven and reliable equipment in our systems.
Cost-effective
Our CIC, Leach-CIP and CIL circuits have the capacity to extract gold and silver up to your expectations.  Through designing and selecting robust and proven equipment, our FLSmidth systems will provide your plant with high reliability and performance, exceeding your expectations for total cost of ownership and operation.  

Features that cultivate better leaching and adsorption

Leach and Adsorption options

  • Carbon Steel Tanks available in various configurations suitable to your build site:
    Steel plate pre-rolled with edges prepared for welding in the field $
    Flanged plate for field erection with final seal welding completed in field $$
    Fully bolted for field erection $$$
  • Cascade or Vertical CIC Columns in Carbon Steel or Stainless Steel Fabrication
  • Leach, CIL and CIP Tank configuration in Cascade (Gravity) Flow or Carousel Design
  • Static or driven (vibrating) trash and carbon safety screens
  • Ancillary Equipment: Structural Steel with Operating Platforms, Slurry Pumps, Carbon Transfer Pumps, Vibrating Screens, High Pressure Sprayers, Automation and Instrumentation, Piping and Valves

Leach and Adsorption Systems options

  • Ore/Metallurgical Testing and Circuit Sizing: Leach and adsorption tests for site-specific solutions to determine recovery performance and overall circuit sizing
  • Process, Layout and Detail Engineering: Electrowinning System Process, General Arrangement and Detailed Mechanical engineering
  • Complete System Engineering: Complete Process, General Arrangement and Detailed Mechanical engineering offered for upstream and downstream processes
  • Troubleshooting services for system and equipment

KREBS® Quick Release™ system for pump rebuilds

Read Story


Stories from FLSmidth