Mercury-Free Gold Mining Technology developed by IAST

EQUIPMENT-Georgetown: Guyana has made significant strides in moving towards mercury free gold mining with the Institute of Applied Science and Technology (IAST) recently revealing its latest technological advancement to facilitate this process.

The IAST invited technical members of the Guyana Geology and Mines Commission (GGMC), including acting Commissioner Newell Dennison and recently appointed Chairman of the Board, Stanley Ming; members of the Guyana Gold and Diamond Miners’ Association (GGDMA) including Mr. Patrick Harding, and other stakeholders to their headquarters to showcase their latest technological advancement in the mining sector.

Also attending were Major General (rtd) Joseph Singh, Special Advisor to President Granger; Chair of the Board of the Private Sector Commission, Major General (rtd) Norman McLean and Dr. Rajneesh Mehra, Director of Pinnacle Green Resources (Guyana) Limited.

Harding had contacted the IAST and suggested to Dr. Narine that the cyanidation/activated carbon route, which is used elsewhere, should be investigated and adapted to Guyana.

Professor Narine, Director of the IAST, explained that over the past two and a half years, the institute has been researching the use of cyanidation and activated carbon (derived from shells of coconuts) for the mercury-free extraction of Gold in Guyana.

Dr. Narine explained that the motivation for the project stemmed from the fact that Guyana had in October 2013 become a signatory to the Minamata Convention, which is focused on the eradication of mercury use in applications which allows it to escape in the environment.

Narine, who is also a Professor at Trent University and Director of the Trent Centre for Biomaterials Research, was able to fund a Guyanese student, Mr. Vishol Kishun (who has significant experience in the Gold sector, having worked at the GGMC), using funding he received as a winner of the Anthony N. Sabga Caribbean Award for Excellence in Science and Technology, to pursue a Masters Degree at Trent University on the subject.

The IAST partnered with local miner, entrepreneur and owner of Guyana’s newest eco-resort, Mr. Chunilall Baboolall on the project.  Mr. Baboolall shipped ore from Guyana at his own cost to Trent University, where Mr. Kishun was able to use the state of the art equipment in the Trent Centre for Biomaterials Research to study the comparative merits of using mercury and cyanidation/activated carbon, on ore directly from Guyana.

Mr. Kishun’s findings were encouraging – the efficiency of gold extraction using the cyanidation/activated carbon approach consistently ranged between 92 to 94 percent, whilst extraction of the same ore under the same controlled conditions using mercury only yielded efficiencies in the range of 30 – 40 percent. Mr. Kishun is now preparing this work for publication in an international journal. However, the laboratory scale investigation, Professor Narine indicated, was more important in a practical sense for it provided the justification for the IAST to invest in At-scale mining equipment, which employs the cyanidation/activated carbon process.

The equipment was bought and modified at the IAST, and Mr. Baboolall once again partnered with the institute to ship ore from his mining operations in the interior to the institute for testing of the At-scale equipment.

The IAST Director and his team were clearly in a heightened state of excitement to report that they have been able to confirm that the At-scale processing equipment delivered similar efficiencies of extraction as the laboratory scale process – between 90 and 94 percent.

The equipment was showcased to the invited stakeholders – the process was deliberately made as simple as possible to allow maximum maneuverability in the field and robust to be able to handle the vigour of the rough terrain in Guyana’s mining sector.

Reactions from the stakeholder community were enthusiastic and extremely positive. Stanley Ming, Chairman of the GGMC and Newell Dennison, acting Commissioner both expressed their gratitude to the IAST for taking this initiative and applauded the project as being both thorough and practical.

The GGMC officials immediately committed to working with the IAST to deploy the equipment. Mr. Patrick Harding of the GGDMA indicated that he felt certain that the technology was impressive enough and robust enough to be immediately adopted by as many as 10 of his organization’s largest miners.

The GGMC and IAST will be working together to mount the equipment on a mobile platform, and this will be deployed shortly to Mr. Baboolall’s concession for further demonstration.  In the meanwhile, construction of a second set of equipment will begin immediately to facilitate access by other miners.

The IAST is also developing a training video and manual for the safe utilization of the chemicals involved and the equipment itself, and an app for Ipads and Mobile Phones for miners to use in the field to determine the amounts and concentrations of chemicals to be used. The GGMC will also be endorsing the technology and helping to disseminate it to the mining community.

Mr. Kishun pointed out that the technology benefits three sectors in the Guyanese economy – the more efficient extraction of Gold will benefit the miners, the removal of mercury from the environment will benefit the environment and biodiversity of the country, and the utilization of coconut shells currently wasted in the country to produce activated carbon will benefit the coconut and wider agricultural industry.

To this end, Pinnacle’s Director, Dr. Rajneesh Mehra indicated at the meeting that they will be moving to immediately supply the local market with high quality activated carbon produced in India, and will be shipping a plant from India (with parts from Germany) to Guyana, so as to produce the material from Guyana’s locally sourced coconut shells.

The IAST has been a proponent of this project for some time, and developed all of the local feasibility studies, which is being used by Pinnacle in their commercial project.

The technology will employ sodium cyanide, which is a harmful chemical.  However, as explained by Mr. Kishun, this chemical does not persist in the environment and is effectively dissipated in sunlight.

Therefore, one aspect of managing this new process will be the training of miners in the safe disposal of cyanide, in lined ponds specifically constructed for this purpose. Mr. Kishun indicated that the technology has so advanced that there are now very accurate hand held devices which will measure the concentrations of cyanide down to parts per billion, which are much lower than the safe levels recommended by the WHO.

Professor Narine was careful to point out that the extraction of gold is not a benign process – “this process does leave a footprint, but by using the best technologies available, we can minimize that footprint and furthermore, leave the environment in a state where it can be rejuvenated by our own efforts and the corrective energies of nature itself.