JANUARY 2017JANUARY 2017

Informed and in-depth editorial on the world mining industry

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FATIGUE & COLLISIONAVOIDANCE

LITHIUM GRAPHITE REEs

SOUTH AFRICANTECHNOLOGY

MAINTENANCE

PROCESS CONTROL & DESIGN

SOUTH AFRICANTECHNOLOGY

MAINTENANCE

PROCESS CONTROL & DESIGN

FATIGUE & COLLISIONAVOIDANCE

LITHIUM GRAPHITE REEs

COVER JANUARY(X)_proof 20/12/2016 16:10 Page 1

54 International Mining | JANUARY 2017

LITHIUM GRAPHITE REEs

Fuelling technology

With ever increasing demand for graphite,rare earths and lithium in key marketssuch as electronics; hybrid electricvehicles and rare earth magnets, PaulMoore looks at some key processing andtechnology developments

Small scale Jameson Cells are ideal for graphitecircuits, particularly for producing final gradeconcentrate

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Graphite developmentsGlencore Technology has been involved with the graphite industry for over 20 years, with several Jameson Cells installed at the Ancuabe operation in Mozambique in the mid 1990s. The company told IM: “However, the industry has been dominated by price slumps and peaks, with the most recent dramatic price increases between 2011 and 2013, having fallen back to sustainable levels. The continued interest in graphite, through the use of lithium batteries for electric vehicles and power grids, as well as graphene production, is offering opportunities for graphite projects worldwide.”

Graphite processing generally involves a flotation stage in its flowsheet, making the most of the natural hydrophobicity of the graphite. Due to the need to have high purity graphite concentrate, the cleaning stage in the flowsheet involves multiple stages of flotation cleaning using conventional cells, with three or four stages

of cleaning not uncommon. However this results

in circuits requiring large floor spaces and infrastructure, and high recirculating loads.

“Work being done by Glencore Technology offers a better solution to conventional graphite

cleaning circuits.” Virginia Lawson, Jameson Cell Manager at Glencore Technology commented:

“Two of the unique aspects of the Jameson Cell is the downcomer and wash water. The downcomer generates fine bubbles and creates high sheer forces, which provide the energy necessary for bubble contact with the graphite. Once the particles attach to the bubbles and pass out of the downcomer in the cell, they rise to the top of the cell. Prior to reporting to the concentrate launder the collected graphite is washed, ensuring the entrapped non floating gangue is washed out of the concentrate. The net result is a very clean concentrate being produced, able to achieve final grade concentrate from just one flotation stage.”

to include a small scale Jameson Cell at the

head of a cleaning circuit to produce final grade concentrate. It can also be used in conjunction with conventional cells to target graphite composites with slow residence times. These circuits can then utilise small scale IsaMills™ to

target the graphite composites for further recovery.”

Glencore Technology works with third party providers who undertake small scale Jameson Cell testwork, and review the metallurgical results and make recommendations for full scale cells and flowsheets for graphite projects.

Lawson adds: “We also think the graphite, a layered anisotropic mineral similar to molybdenum, also benefits from the turbulent and random collisions of particles and bubbles in the downcomer, while in a conventional cell, the minerals and bubbles tend to flow parallel to each other, following natural flow lines produced in the cell, reducing the chance of bubble and particle collision. Considering the small tonnages cleaned in most graphite circuits, and the superior grade recovery curves we have seen for testwork to date, it provides a good opportunity

Original unabridged story available on International Mining website: https://www.joomag.com/magazine/im-2017-january/0696058001483186480?access_key=8c576d484323d1e3e33519eb1da7cd22