Tag Archives: Herrenknecht

Anglo American eyes polyhalite potential with Sirius Minerals bid

Anglo American has gone public with a bid to buy Sirius Minerals and its North Yorkshire polyhalite project in the UK.

The all-cash bid, which values Sirius at £386 million ($507 million), comes shortly after Sirius announced a strategic review for the project that included a broader process to seek a major strategic partner for the asset.

Anglo says it identified the project as being of potential interest some time ago, given the quality of the underlying asset in terms of scale, resource life, operating cost profile and the nature and quality of its product.

The North Yorkshire polyhalite project, which is spilit into two stages, will see product extracted via two mine shafts and transported to Teesside, in the northeast of England, on a conveyer belt system in an underground tunnel. It will then be granulated at a materials handling facility (MHF), with the majority being exported to overseas markets.

Infrastructure development on the project includes sinking the shafts at the Woodsmith mine to access the polyhalite deposit (using Herrenknecht’s Shaft Boring Roadheader); developing a 37 km-long underground mineral transport system using tunnel boring machines; constructing a MHF in Teesside for granulating or chipping the mined material into the final product; and harbour facilities comprising an approximately 3.5 km-long overland conveyor, a ship berth and a ship loader located adjacent to the harbour on the River Tees.

In its announcement this morning, Anglo said: “The project has the potential to fit well with Anglo American’s established strategy of focusing on world-class assets, particularly in the context of Anglo American’s portfolio trajectory towards later cycle products that support a fast-growing global population and a cleaner, greener, more sustainable world.”

Anglo is not new to the fertiliser market having, until 2016, a phosphates business in Brazil. It sold the mine, beneficiation plant, two chemical complexes and two further mineral deposits that made up this business that year to China Molybdenum in a $1.5 billion deal that also included its niobium assets.

Sirius announced its strategic review back in September 2019 after it had to terminate a $2.5 billion revolving credit facility stage 2 financing for the project (to get it to 20 Mt/y capacity) due to a worsening of market conditions for a required bond raising.

This led to the company slowing development across the project in order to preserve funding to allow more time to “develop alternatives and preserve the significant amount of inherent value in this world-class project”, Chris Fraser, Managing Director and CEO, said at the time.

This saw the company lay out a pathway that would still see first polyhalite production in the June quarter of 2022, but could see the ramp-up to stage one 10 Mt/y polyhalite capacity reached in the September quarters of 2025 or 2026, depending on if there was a 12 or 24 month deferral of the planned development scope.

Anglo said, during the first two years after an offer is successfully completed, development work on the project is expected to be broadly in line with Sirius’ revised development plan “although Anglo American intends to update the development timeline, optimise mine design and ensure appropriate integration with its own operating standards and practices”.

It added: “Anglo believes that the project has the potential to become a world-class, low-cost and long-life asset. Sirius has progressed the development of the project to an advanced stage, with construction now under way for over two years.

“Sirius has indicated that this is currently the world’s largest known high-grade polyhalite deposit with a JORC reserve of 290 Mt, with a grade of 88.8%, and a resource of 2,690 Mt. The resource indicated by Sirius has the scale, thickness and quality to be mined efficiently using bulk mining methods through a relatively simple, low-energy, non-chemical production process.”

In addition, Sirius has indicated the project could operate at an EBITDA margin potentially well in excess of 50%, according to Anglo, leaving the project well positioned for strong through-the-cycle profitability with a long anticipated asset life.

“At this stage, the project requires a significant amount of further financing to develop and commission the operation that has proven challenging for Sirius to procure on an economic basis,” the diversified miner said. “Anglo American, as one of the world’s leading mining companies, has the resources and capabilities to help build on the achievements of the Sirius team. Anglo American remains committed to its disciplined capital allocation framework.”

Anglo explained that there is potential long-term benefits in applying its technical expertise in both the development and operational phases, as well as utilising its recognised Operating Model to drive safety and productivity to “world-leading standards”.

“Integration into Anglo American’s global marketing network would provide full mine-to-market capabilities and build on Anglo American’s institutional experience in the world’s major fertiliser markets,” it added.

Sirius’ polyhalite product, POLY4, is a multi-nutrient fertiliser certified for organic use and has the potential to generate demand at a competitive cost that supports a strong margin, according to Anglo.

“POLY4 is an attractive low-chloride alternative to traditional potassium-bearing mineral products on a cost-effective basis. It includes four of the six key nutrients that plants need to grow – potassium, sulphur, magnesium and calcium,” it said. “The use of fertilisers is one of the most effective ways to improve agricultural yields and therefore help to address the anticipated future imbalance between food, feed and biofuel demand and supply caused by a fast-growing global population and limited additional land availability for agricultural use.”

Herrenknecht brings boxhole backreaming to shaft sinking market

Herrenknecht expects to install one of its new boxhole backreaming machines in a mine in Asia later this year, one of the company’s Mining Project Managers, Alexander Frey, told attendees at an SME technical presentation, in Denver, Colorado, last week.

Looking to produce a system able to develop ore passes with simultaneous drilling and lining, the company has adapted boxhole boring machines it has been working on for the past nine years – which use an adapted form of the pipe jacking method – and come up with the boxhole backreaming machine.

This new machine can stabilise the shaft with thrust pipes and a steel liner, which avoids collapses of the shaft or a rework, while reducing the amount of activities in the upper level during mine development.

Herrenknecht has already built one machine and tested it at a mine in the Black Forest of Germany, Frey said. This testing saw the company sink an ore pass with a 2.8 m diameter and 22 m length at an angle of 19°. During this test work in 150 MPa Gneiss rock, Herrenknecht achieved reaming rates of up to 1.3 m/h, Frey said. According to Frey, the machine, which is equipped with a cutterhead like those employed on raiseborers, can cut really hard rock.

He added that the machines would likely be used for safely and efficiently sinking ore passes with a maximum 70 m shaft length and 3 m diameter, but it could also find other industry applications.

Rio Tinto starts up TBM at Kemano Second Tunnel project in Canada

Rio Tinto, together with the Cheslatta Carrier and Haisla First Nations, has celebrated the launch of the tl’ughus tunnel boring machine, a key milestone towards completing the Kemano Second Tunnel project for the BC Works aluminium smelter in Kitimat, British Columbia.

The 1,300 t machine was named by the Cheslatta Carrier nation after a giant snake that, according to legend, once bored through the mountains and landscape around the nearby Nachako Reservoir.

It will dig 7.6 km of tunnel through a mountain as part of a C$600 million ($458 million) project to enhance the long-term security of a clean power supply for the BC Works smelter.

Rio Tinto Aluminium Managing Director Altantic Operations, Gervais Jacques said: “Launching the tl’ughus in partnership with the Cheslatta Carrier and Haisla First Nations is an important milestone for our world-class aluminium operations in British Columbia. Our smelter in Kitimat produces some of the world’s lowest carbon aluminium and this project will enhance the long-term security of its supply of clean, renewable hydropower.”

Construction of the Kemano Second Tunnel project is expected to be complete in 2020. It will supply the Kemano powerhouse with water from the Nachako Reservoir, creating a back up to the original tunnel built over 60 years ago.

Frontier Kemper Aecon has been selected as the main contractor for the project, with Hatch being the EPCM. Herrenknecht has supplied the TBM.

The project will see some 250,000 m³ of tunnel rock excavated by the tl’ughus, while 8.4 km of an existing portion of the second tunnel (excavated in the 1990s) will be refurbished.

Phase 1 of the project was completed in 2013 to coincide with the Kitimat Modernisation project and involved construction of interconnections to the existing portion of the second tunnel.

The Cheslatta Nation selected the name for the tunnel boring machine – tl’ughus – as it shares many parallels with the Kemano second tunnel project, according to Rio.

Kitimat produced 433,000 t of aluminium last year, up from 408,000 t in 2016 and 110,000 t in 2015.