Kell Process – Opening The Way For Full Spectrum Platinum Beneficiation

By Author: kellprocess name
Total Articles: 2
Comment this article

Kell Process has transformed the way metallurgical engineering worked. It is a robust, yet flexible solution that uses a fraction of the electricity consumed in smelting. The process removes the grade constraint, resulting in extraction of more platinum in the plants.

Kell Process is a smelting alternative in the processing of platinum group metals (PGMs). It slashes electricity consumption by doing away with the power-guzzling smelting step, opening the way for full spectrum platinum beneficiation.

Kell’s hydrometallurgical process transudes the PGMs out of the concentrate. It eliminates the need to melt the concentrate at 1600C, which is like using the sledgehammer to crack the nut. Kell Process consumes just 14% of the electricity in comparison to smelting – 140 kWh of electricity for every ton of concentrate processed vs. 1000 kWh of electricity for every ton of concentrate smelted. The main reason that Kell consumes only a fraction of smelting’s power requirement is that the waste concentrate moves through the process without being altered and without consuming any electricity.

Emission of lower ...
... amount of carbon dioxide and no milling means that the process is even more environment-friendly. It emits only 440 kg of carbon dioxide (CO2) a ton of concentrate treated compared with 1400 kg of CO2/t done while smelting the concentrate.

Kell Process was initially used as a treatment route for concentrate sourced from UG2 platinum reef in South Africa. It copes well with the chromite in the concentrate, which smelting finds problematic. Smelters have to use the floatation process to deal with chromite. However, this results in the lost recovery of the metals. The process removes the grade constraint, resulting in 5% more platinum being recovered in the plant.

Thanks to consistent refinement since 1999, the year when it was patented, Kell is now a robust process with flexible implementation. Operating conditions of the process can now be modified as per the requirements, making the process applicable to the concentrates that base metals like nickel, copper and cobalt.

Kell Process is not only operationally economic, but it also brings down capital investment. The process makes use of standard pieces of off-the-shelf or out-of-the-catalogue equipment. The modularity feature eliminates the need to put in money in a big smelter.

Another major advantage Kell Process offers is that it is in sync with the refining process of the PGMs. In fact, the third stage of Kell Process makes the first stage of the refining process. At this stage, all metals are in the form of solution, making it easier for the companies to decide what they want to get from it. Kell Process draws to forth the true value of hydrometallurgy.

Being a flexible solution, Kell Process allows more parts to be added, depending on the capital expenditure to facilitate the manufacture of items like auto catalysts or fuel cells. As the metallurgical engineers go down the process stream, it is likely to be refined even more.

Kell Process follows a flow sheet that provides a viable hydrometallurgical process for treating concentrate. It broadly comprises the selective leaching of base metals by pressure oxidation, followed by the leaching of PGMs after a roasting pretreatment step. The process works well for different minerals. Different concentrates put to the test have all given 99% platinum recovery.

Author of this article is an expert in Kell Process, which is considered a major innovation in the field of metallurgical engineering.