Tag Archives: thermal fragmentation

Nippon Dragon refining thermal fragmentation process at Rocmec 1

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Nippon Dragon Resources, a pioneer of the innovative thermal fragmentation mining process, says it has begun transforming its flagship gold property Rocmec 1, in Quebec, Canada, into a dynamic mine through investments in exploration, development, infrastructure and equipment.

In January, the company produced 1,000 t of mineralised material from the project. With the implementation of strict grade control procedures, the samples returned average grades of 6.5 g/t Au.

Nippon says plans have been completed to ramp up production to 3,000 t/mth within the next six months.

Mining at Rocmec 1 is based on state-of-the-art technology that integrates management and planning processes into digital platforms for project control and reporting, the company says. While it is currently finalising agreements with third-party milling facilities to readily bring bullion to market, its plans are to build a processing facility underground at Rocmec 1.

“Through the use of a completely mechanised thermal fragmentation extraction process, highly concentrated mineralised material is produced with minimum dilution,” the company explained. “Minimum mining waste is produced, and all waste material is stored underground, with zero environmental impact. Mine water is also recycled, drastically reducing our environmental footprint.”

Nippon has an exclusive licence for the thermal fragmentation mining process for narrow vein mining. The process involves drilling a series of 6 in (15 cm) pilot holes into the vein with a conventional drill. Thermal fragmentation (thermal head, compressed air and water) is then inserted and spalls the rock, quickly increasing the diameter of the hole to 30-110 cm. After this, ore can be extracted in 0-13 mm fragments. The leftover rock between fragmented holes is then broken to recover the remaining ore.

The proposed development plan at Rocmec 1 is based on the company’s permit to extract up to 44,000 t of mineralised material underground from its mining lease. The company says it is working on preparing and gathering the required information for the various government agencies and authorities to go beyond the permitted 44,000 t.

Alongside this work at Rocmec 1, Nippon says it has established a series of agreements with “renowned engineerin firms” to provide engineering services and support to operations. Service agreements have also been made with organisations to provide mining supplies and equipment maintenance services, it said.

The development and production equipment fleet has also been recently upgraded to meet the production targets, it said. Nippon has, in particular, optimised its thermal fragmentation units to permit full recovery of its narrow vein mineralised material economically and with minimum dilution.

Nippon Dragon’s thermal fragmentation tech gets to work at Rocmec 1

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Nippon Dragon Resources says it is using its thermal fragmentation technology on the Talus vein at its Rocmec 1 gold mine, in Quebec, Canada.

In a progress report this week, Nippon Dragon said thermal fragmentation operations had begun on the Talus vein – “probably a secondary sub parallel branch structure to the McDowell vein”, the company says – where grades range from 0.03-61.58 g/t Au and widths vary from 0.05-3.04 m, according to sampling.

Alongside this, the company said development of a raise and a sub-level on level 39 within the Talus mineralised structure had started from level 50. At the same time, development of two drifts in the mineralised vein on level 50 of the McDowell structure, which has the longest gold-bearing structure on the property, had begun.

It added: “Employee training on the thermal fragmentation units continues in an accelerated mode.”

Nippon has an exclusive licence for the thermal fragmentation mining process for narrow vein mining. The process involves drilling a series of 6 in (15 cm) pilot holes into the vein with a conventional drill. Thermal fragmentation (thermal head, compressed air and water) is then inserted and spalls the rock, quickly increasing the diameter of the hole to 30-110 cm. After this, ore can be extracted in 0-13 mm fragments. The leftover rock between fragmented holes is then broken to recover the remaining ore.

This precision allows for the extraction of high-grade precious and base metal veins without dilution, according to Nippon.

To date, Nippon Dragon has invested approximately C$33 million ($25 million) in rehabilitating the Rocmec 1 property, surface and underground infrastructure, diamond drilling, equipment and drifting. The property includes a 100 m deep two compartment shaft, an 844 m decline allowing access to five levels (50, 70, 90, 110 and 130 m). On these levels, a total of 1,700 m (drifts and cross-cut drifts) were driven.

A 2010 NI 43-101 report by SGS using a cutoff grade of 3 g/t Au reported a measured and indicated mineral resources of 570,300 t grading 6.52 g/t for 119,500 oz of gold and 1.51 Mt of inferred resources at 7.4 g/t Au for 359,600 oz of gold.

Nippon thermal fragmentation tech proves its worth at AngloGold narrow vein mine

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Nippon Dragon Resources has revealed more details about testing of its exclusive and patented thermal fragmentation technology in South Africa following a recent presentation from AngloGold Ashanti.

The company’s South Africa distributor, MaXem, who attended the open-day presentation organised by the Mandela Mining Precinct, provided the details, Nippon said.

Nippon’s thermal fragmentation process for narrow vein mining involves drilling a series of 6 in (15 cm) pilot holes into the vein with a conventional drill. Thermal fragmentation (thermal head, compressed air and water) is then inserted and spalls the rock, quickly increasing the diameter of the hole to 30-110 cm. After this, ore can be extracted in 0-13 mm fragments. The leftover rock between fragmented holes is then broken to recover the remaining ore.

This precision allows for the extraction of high-grade precious and base metal veins without dilution, according to Nippon.

AngloGold Ashanti, which is a MaXem client, said over 200 holes were drilled and fragmented using the thermal fragmentation technology at one of its underground operations in South Africa. Of these holes, several exceeded 30 m in length.

One of the objectives of the test work was to drill, fragment, clean and backfill a hole within a 25-hour period; an objective the company achieved, Nippon said, adding that over the 200 holes completed, productivity ranged from between 3-6 t/h.

Two other projects are currently under review by the Non-Explosive Rock Breaking Programme within the Mandela Mining Precinct, MaXem and other partners, according to Nippon. One of these is the spallability classification of different rock types and the other is the employability of the thermal fragmentation technology within the platinum sector.

The Mandela Mining Precinct is established as a public and private partnership between the South African Government, the mining companies, manufacturers of mining equipment, research organisations and academia to foster collaboration and innovation. It “assists the mining industry in bringing change to processes, technologies, skillsets and social and environmental impacts associated with current mining through the modernisation of mines via mechanisation and automation”, Nippon says.