Kell Process Solutions & Applications

Application of Kell to provide a process solution to the recovery of metals from a particular sample typically follows the workflow outlined in the Testing & Engineering section at the bottom of this page. Some example applications of Kell into the industry are given in the following sections.



Platinum Group Metals

Kell Process is working with most of the major and mid-tier PGM producers and several explorers in assessing specific potential Kell Process applications.

The Kell Process Plant at Sedibelo Platinum Mines’ (SPM) Pilanesberg PGM Mine


A Kell plant has been approved for construction at Pilanesberg Platinum Mine in South Africa, subject to financial closure. The project has sufficient resources for 50 years of mining. A world class PGM concentrator – processing of 220 ktpm Merensky ore and 75 ktpm UG2 ore, producing 15,000 oz/m PGM (Pt, pd, Rh, Au) plus Cu, Ni and Co in concentrate.

Kell plant target products: Pt, Pd & Au sponges; Cu cathode; Ni & Co sulphates (battery grade)

  • Plant throughput: 110,000 tpa
  • Feed concentrate: 60,000 tpa PPM UG2 & Merensky concentrates
  • Design/Construction: 21 months
  • Commissioning: 3 months
  • Ramp-up:18 months
  • Construction phase: ~300 jobs
  • Operations phase: 144 jobs

Kell Metallurgical Complex in Zimbabwe

The Kell team has extensive experience working with the Government in Zimbabwe where beneficiation and “full value addition” continues to be a pillar of their domestic policy.  

The Kell Process is uniquely positioned to provide Zimbabwe a leapfrog solution to the platinum sector.  An innovative, hydrometallurgical complex to process PGM’s in Zimbabwe removes the need for dirty, SO2 emitting smelters, base metal refineries, precious metal refineries and additional thermal coal power stations to be built.  All of which would require a decade and billions of capital investment in archaic plants.

In May 2017 a binding Memorandum of Agreement was concluded with Government to construct several Kell plants in Zimbabwe.  The Government has also issued Kell with a Government guarantee from the Cabinet of Zimbabwe that will ensure local beneficiation is achieved.

Kell is committed to helping Zimbabwe embrace innovative advancements in mining technology that will lead to a period of high GDP growth.  In addition to PGM’s, Kell is working with local partners to establish a hydro-metallurgical “Hub of Excellence” that will beneficiate refractory gold, lithium, nickel, copper and other key minerals.

Refractory Gold

Kell is working with major, mid-tier and junior gold producers and explorers to assess Kell application to treat different gold-bearing materials, for example:

  • High-grade carbonaceous polymetallic ore
  • Refractory gold concentrate
  • Refractory gold polymetallic concentrate
  • Double refractory Cu-Au concentrate

Kell Application to a ‘Triple Refractory’ Gold Concentrate

An engineering study and supporting laboratory testwork has been completed to assess a Kell plant as a solution for treating a ‘triple refractory’ gold concentrate from which gold is not recoverable using cyanide. Subject to review and approval, this application would target production of 99.99% gold, fine (99.9%) silver and A Grade LME copper cathode (99.9935%) directly on site for sale to end users.

Cyanide would not be used in the process, eliminating the need for cyanide management, handling and detoxification and further eliminating the risks of wildlife deaths in cyanide tailings dams.

Other Kell Applications

Several Kell applications are being actively assessed for different feed materials and are at various stages of the testing, engineering and financial analysis workflow:

  • Polymetallics
  • Base Metals
  • Lithium (hard rock and brines)
  • Autocat Recycling

Testing & Engineering

The following workflow outlines the generic development path for any particular Kell application. In some instances the client may choose to fast-track via parallel workflows. Kell has worked with Simulus Engineers & Laboratories in Perth Australia since 2010 for provision of Kell testing & engineering services. 

  • Laboratory scale amenability test (~10 kg) developed to take a sample through all process stages and determine metal extractions
  • Batch testing successfully completed for ~20 PGM, gold and polymetallic ore producers
  • Some 20 Scoping and Prefeasibility level studies and preliminary economic assessments completed, all show attractive returns, particularly when Kell replaces smelting offtake contracts
  • Pilot testing successfully completed for several PGM producers in 2011-2016
  • Feasibility study successfully completed for SPM in 2013-2016 for installation of a 280 koz/year Kell plant at its minesite supported by optimization pilot testwork totaling 9 weeks of integrated continuous operation
  • Long-lead capital items detailed design
  • Design and fabrication of modular process skids
  • Plant construction and commissioning