The Oyu Tolgoi gold and copper project, also known as Turquoise Hill, is situated in the south Gobi region of Mongolia, around 80km north of the Chinese-Mongolian border and 550km south of Ulaanbaatar.
It is one of the biggest gold and copper mines in the world and has the potential to produce more than 500,000 tonnes per annum (tpa) following improvements in 2027.
The mine is jointly owned by multinational resources company Turquoise Hill Resources (66%) (previously Ivanhoe Mines) and Erdenes OT, owned by the Government of Mongolia (34%). Rio Tinto, which has a 51% stake in Turquoise Hill Resources, has been operating and managing the development of the Oyo Tolgoi mine since 2010.
An integrated development plan (IDP) suggests that the Oyu Tolgoi Mine will be capable of average annual production in excess of one billion pounds of copper and 330,000oz of gold for at least 35 years. Peak annual production exceeding 1.2 billion pounds of copper and 650,000oz of gold is projected for the first ten years.
On 31 March 2010, Turquoise Hill Resources announced that the necessary conditions to develop and operate the mine were completed.
The development phase of the project began following approval by the Mongolian Government in April 2010. Approximately $758m has been approved by a joint committee between Turquoise Hill Resources and Rio Tinto.
In 2011, a new zone of shallow copper-gold-molybdenum mineralisation was discovered approximately 10km north of the Oyo Tolgoi property, extending the deposit’s strike length beyond 23km.
Investment agreement with Mongolian Government
In 2009, an investment agreement between Turquoise Hill Resources, Rio Tinto and the Mongolian Government was presented in parliament after getting approval from the Cabinet and the National Security Council.
During the same period, Turquoise Hill Resources entered an agreement with GoviEx Gold to introduce proprietary Zeus technology at Oyu Tolgoi in an expanded induced polarisation survey. The survey will test Oyu Tolgoi’s copper and gold mineralised trend.
Oyu Tolgoi owners signed a $4.4bn project finance agreement with global financial institutions and export credit agencies from the US, Canada and Australia, as well as 15 commercial banks in December 2015. The agreement includes an additional $1.6bn supplement debt to complete underground development.
Geology and reserves
The South Gobi area lies near the boundary of the South Mongolian and the South Gobi tectonic units. Mainly Palaeozoic volcanic, sedimentary and intrusive rocks and Mesozoic sedimentary cover underlie the region.
The series of deposits discovered by Turquoise Hill Resources at Oyu Tolgoi and on the adjoining Shivee Tolgoi joint-venture property during the past six years stretch across 6.6km, and have a total proven and probable reserves of 1.45 billion tonnes graded at 0.86% Cu, 0.30g/t Au and 1.97g/t Ag as of December 2015.
Mining at Turquoise Hill
Turquoise Hill is developing a stage one open-pit mine on the near-surface Southern Oyu deposits and a stage two underground block-caving mine at the Hugo Dummett North and South deposits. The initial development programme for the Hugo North underground block cave mine is currently underway with a 1,385m shaft no.1 completed in 2009. In the same year, lateral development continued. Preliminary works for the development of a raise-bore ventilation shaft was also carried out at shaft one. Surface works for constructing shaft two were also undertaken in 2009.
“The Expanded Case envisions the ramping up of production from the underground block-cave mines.”
The first phase, the Base Case, consists of a concentrator with a single SAG (semi-autogenous grinding) circuit with an initial throughput rate of 100,000tpd. In March 2010, the key mining equipment was purchased. It included the major components for the 100,000tpd phase one copper-gold concentrator.
Production at Hugo North is expected to commence in 2021, with average production exceeding 550,000t of copper and 450,000oz of gold from 2025 to 2030. The softer, underground mill feed is expected to support a higher throughput rate of 95,000tpa of SAG milling capacity in the concentrator circuit comprising two grinding lines each installed with a SAG mill and two parallel ball mills.
Phase two of the IDP, the Expanded Case, will start with a decision in year three to develop a block-cave mine at the Hugo South Deposit and proceed with the stripping of stages three and four of the open-pit mine.
The Expanded Case envisions the ramping up of production from the underground block-cave mines and the doubling of the capacity of the concentrator, including the addition of a second SAG milling circuit, to increase Oyu Tolgoi’s underground production to at least 140,000tpd by year seven.
Production and costs of Oyo Tolgoi
Oyo Tolgoi owners believe the project has the potential to achieve a mill throughput of 95,000tpd.
Provided that the expansion is undertaken as scheduled, the IDP indicates that Oyu Tolgoi open pits could produce 35 billion pounds of copper and 11 million ounces (Moz) of gold over the projected, initial 35-year life of the mine, based on resources delineated to May 2005. IDP’s sensitivity analysis shows that the project’s rate of return is most sensitive to changes in the copper price, followed by changes in the gold price, changes to the operating costs and, finally, changes in capital costs.
It states that at $1.10 copper and $400 gold, the after-tax IRR increases to 22.08%; the after-tax NPV increases to $3.39bn at an 8% discount rate and $2.39bn at a 10% discount rate.
According to the 2016 Oyo Tolgoi feasibility study, the project’s open-pit and underground mine operations are together expected to produce 23.87 billion pounds of Cu, 10.44Moz Au, 74Moz Ag over a mine life of 40 years.
Molybdenum production is anticipated towards the second half of the project’s expected operational period of 100 years. The first shipment of copper concentrate took place in July 2013 while the mine produced nearly four million tonnes of shipments by July 2018.
see & read more on
https://www.mining-technology.com/projects/oyu-tolgio/
Rio Tinto Copper
Our very first mine was a copper mine on the banks of the Rio Tinto river, in Andalusia, Spain – bought in 1873 by a British-European investor group led by Scottish entrepreneur Hugh Matheson.
Today, our copper operations around the world are at various stages in the mining lifecycle, from exploration to rehabilitation. At each of our copper operations, we use leading-edge technologies that drive safe, efficient and productive methods of extracting, processing and refining copper, supplying customers in China, Japan and the US.
Oyu Tolgoi, in the South Gobi region of Mongolia, is one of the largest known copper and gold deposits in the world. When the underground is complete, it will be the world’s largest copper mine.
South Gobi, Mongolia
Oyu Tolgoi, in the South Gobi region of Mongolia, is one of the largest known copper and gold deposits in the world. It is also one of the most modern, safe and sustainable operations in the world. When the underground is complete, it will be the world’s third largest copper mine.
Open pit mining began at Oyu Tolgoi in 2011 and the copper concentrator, the largest industrial complex ever built in Mongolia, began processing mined ore into copper concentrate in 2013. Current infrastructure at Oyu Tolgoi will allow the mine to operate for decades to come.
Oyu Tolgoi is jointly owned by the government of Mongolia, which has 34% ownership, and Turquoise Hill Resources, which owns 66%. Rio Tinto owns 50.8% of Turquoise Hill Resources and manages the operation on behalf of the owners.
Innovation at Oyu Tolgoi
Most of the value lies deep underground and to reach the ore body we are building a world-class underground mine. It will include a state of the art control room to oversee the operation that will have approximately 200 kilometres of tunnels.
3.4BT
Ore Reserves
5 Shafts
Deepest Reaching 1.3KM
5.5m x 5m
Average Tunnel Height & Width
We will use leading underground mining technology known as block caving to mine the ore body. Block caving is technically complex, but it is also one of the safest and most cost-effective methods of mining ore from deep below the ground as it uses the force of gravity.
Put simply, a void is created under the ore body, which then collapses gradually under its own weight. The ore passes through ‘funnels’ in the rock, known as draw points. A series of lateral tunnels over several levels are used to extract the ore and to haul it for crushing before it is transported to the surface via shaft or conveyor belt.
We have made significant progress on a number of key elements in the construction of the Oyu Tolgoi underground mine during 2019. However, the ground conditions are more challenging than expected and we are reviewing our mine plan and considering a number of mine design options. Delays are not unusual for such a large and complex project and we are focused on finding the right pathway to deliver this high value project.
We have the world’s best underground mining experts working on delivering the revised mine design in the first half of 2020. Once the design has been finalised, we will progress with a definitive estimate of cost and schedule for the project in the second half of 2020.
At Oyu Tolgoi, we are using technology to build a connected mine and keep our people safe. We are installing a wireless network to connect our people and equipment underground with the teams on the surface. All team members have a Personal Location Indicator, which allows us to track their whereabouts, providing critical information during an emergency. Similar sensors allow us to track the location and performance of all equipment and we have real time monitoring of atmospheric conditions. The team in Mongolia are supported by the Rio Tinto Underground Mining Centre, which connects our caving experts in the Brisbane hub with our operations team at Oyu Tolgoi. These groups work together to improve safety and productivity performance by using the vast amount of data being collected.
Growth
Global demand for copper is set to grow, driven by urbanisation, industrialisation and increasing requirements for renewable energy: copper plays a key role in electrification and power production. For example, a wind turbine capable of generating a megawatt of power – enough to supply several hundred homes – needs more than three tonnes of copper.
Given its significance to the global copper industry and the likely multi-generational nature of the business, Oyu Tolgoi is being developed with a distinctly long-term view. Guided by Oyu Tolgoi's vision, 'From natural wealth to enduring value, knowledge and skill', the partners and stakeholders involved in the project are focused on delivering a safe and globally competitive copper business that contributes to and facilitates the prosperity of Mongolia.
At full production, the underground mine will produce 95 thousand tonnes of ore each day. This will triple Oyu Tolgoi’s annual production of copper concentrate; making us the world’s third largest copper mine.
see & read ore on
https://www.riotinto.com/Operations/mongolia/oyu-tolgoi
Our Kennecott mine is a world-class, integrated copper mining operation located just outside Salt Lake City, Utah, in the United States. In 2019, after 75 years of operation, Kennecott retired its coal-fired power plant in Magna, Utah. Power for the operation will come from renewable energy certificates purchased from Rocky Mountain Power – primarily from wind and solar resources.
Closing the plant and acquiring renewable energy certificates will remove more than one million tons of carbon dioxide every year from Kennecott’s Wasatch Front operations, reducing its annual carbon footprint by as much as 65%. The renewable energy certificate program is Green-e energy certified, and meets the environmental and consumer-protection standards set by the Center for Resource Solutions.
In the US, the Resolution Copper Project reached a significant milestone in 2019 with the release of a Draft Environmental Impact Statement (DEIS) which will allow us to continue progressing one of the world’s most significant copper deposits towards development.
Our Winu Project, a copper and gold system in Western Australia, is at a very early stage, but our initial results are promising.
Rio Tinto, Turquoise Hill en Entree Resources are partners in this Oyu Tolgio project. |
