subject: Advantages Of Kell Process In Extraction Of Platinum Group Metals [print this page] Kell Process brings in an array of advantages like easy processing, more metal yield, lesser power costs and environmental benefits. It is a robust process which can be implemented in flexible manner. The process has been developed in recent years to make it even more advanced.
Kell Process has changed the way platinum group metals (PGMs) were processed. It considerably lowers electricity consumption in the processing by doing away with the power consuming smelting step, offering the producers a substitute to smelting of their flotation concentrates. The process recovers approximate 99% of the platinum and 98% of the residual platinum group metals and base metals.
Major advantage of Kell Process is it uses just 14% of the electricity in comparison to smelting. While smelting consumes 1000 kWh of electricity for every ton of concentrate, Kell uses just 140 kWh of electricity for every ton of concentrate processed. This is because the waste concentrate moves through the process without consuming any electricity.
The process is environment-friendly as well as it emits lower amount of carbon dioxide and involves no milling. Only 440 kg of carbon dioxide (CO2) per every ton of concentrate treated is released compared with 1400 kg of CO2/t done while smelting the concentrate.
Easy processing, more metal yield, lesser power costs and environmental benefits are not all the advantages Kell Process bring in. Over the decade, the process has been developed to become more advanced. Now, the process can tackle the chromite in upper group two (UG2) reef, which was tricky for smelting which used the floatation process to cope with the chromite, resulting in the loss of recovery.
Going through a series of refinement, Kell is a powerful process which can be implemented in flexible manner. Producers can modify the operating conditions of the process as per the requirements, making it applicable to the base metals like nickel, copper and cobalt. Not only is the system operationally economic, but it also reduces capital investment, bringing down the total costs.
Kell Process allows greater concentrate of mass pulls, has higher tolerance to intergrowths in concentrates and provides substantial increase in PGM recovery. Commercially proven unit operations are embodied in the Kell Process, after comprehensive testing and process modeling.
Considerable technical upside can be gained from the application of hydrometallurgical processing route to process PGM concentrates. If the processing route is capable of handling lower grade concentrates having elements deleterious to conventional smelting, it offers several flowsheet possibilities. These include supplementing the processing stages and treatment of the entire concentrate stream. Hydrometallurgical treatment of low-grade concentrates and middling streams is blended with higher-grade concentrates to produce smelter-compliant feed.
Kell Process has been successfully tested on different sulphide concentrates, showing high extraction efficiency for the metals Pt, Pd, Rh, Au, Ni, Co, Cu. The process was recently subjected to extensive sequential testing and comparison against twenty plus alternative flow sheet variations including several hydrometallurgical approaches and variants. The objective was to undertake a fatal flaw analysis and advise on improvements that could be made to optimize the process. Recommendations of the engineers were incorporated into subsequent testing and process design, resulting in the development of a robust processing system, which is even more effective in precious metals recovery. Thanks to the advantages it brings in, Kell Process is increasingly making inroads in the field of metal extraction.
