Tasiast Archives - International Mining

A bespoke end-to-end switchgear and circuit breaker solution from ABB Electrification is powering up a new solar plant at Kinross Gold’s Tasiast operation in Mauritania, which is looking to significantly reduce emissions via the use of renewable energy.

The Tasiast project has recently increased capacity to 24,000 t/d of gold while reducing costs.

To help meet the company’s sustainability targets, an integrated PV solar plant has been finalised – with power generation capacity of 34 MW and a battery system of 18 MW – to provide around 20% of the site’s power.

The Tasiast solar project is expected to reduce greenhouse gas emissions by approximately 530,000 t over the life of the mine, which could save approximately 180 million litres of fuel over the same period, according to the company. The new scheme is also contributing to the Government of Mauritania’s GHG reduction targets in the country.

Long standing ABB partner, Voltalia, based in Portugal, was tasked with the systems integration and value chain of the new project. Despite already being covered for protection relays, IED and energy metres, the main MV switchgear required integration in the Low Voltage Compartment (LVC) and interoperability with other devices from different manufacturers, so all components operated in conjunction, complementing each others functions and meeting all customer demands.

Subsequently, ABB specified 15 SF6-free and UniGear ZS2 air insulated switchgear panels. These offer additional benefits such as a smaller footprint, easy maintenance and assembly, plus withdrawable voltage transformer, according to ABB. The solution also included 13 of ABB’s VD4 vacuum circuit breakers – there are more than two million in active operation globally – which minimise maintenance and costly downtime, increase safety and provide primary and secondary protection guarantees.

Jeremy Martin, Project Manager at Voltalia SA, said: “Working with ABB on the Tasiast solar project was again a good experience. ABB’s technical expertise played a key role in achieving our objectives for this project. Working alongside a committed partner like ABB reinforces our belief that collaboration can bring about real change.”

Crucially, ABB technology comes with compact dimensions free of SF6 insulating gas in the switchgear or the circuit breaker – without compromising performance, safety or reliability – which was a key differentiator for both Voltalia and Kinross, ABB says.

With the relays taking up significant space and having to be fitted within the confines of the LVC door, without interfering with the wiring and other components, the ZS2’s footprint flexibility proved ideal, according to ABB. For extra protection, ABB also integrated two relays in one panel and the Relion RED615, with its superior line differential protection and control for incomer units, complemented the functionality required and fitted in the tight LVC door front access, it added.

Nuno Nunes, Sales Engineer at ABB Portugal, said: “The mining industry is committed to reducing its emissions and integrating more renewable energy sources, so it was great to be involved in this innovative project, which uses our space-saving and SF6-free switchgear and circuit breakers to help provide continuous power supply for the new solar plant to operates at peak levels.”

Nida Deveci, Sales Manager and UGUR ACAR Project Manager for ABB Turkey, explained: “The factory acceptance test with our partner Voltalia was successful at the first attempt and proved that the collaboration and understanding was clear and good from the offset. They were very pleased with the speed of our responses and appreciated the technical revisions and adjustments we brought to the table to complete the process satisfactorily for all concerned parties.”

Aggreko has helped Kinross Gold shore up its power supply at the Tasiast gold mine in Mauritania, providing a turnkey heavy fuel oil (HFO) solution that has given the company time to review its longer-term energy needs.

The Tasiast mine is one of the largest open-pit gold mines in Africa, located in the remote north western region of Inchiri in Mauritiana.

As an off-grid mine it needed to have its own power supply and was being powered by a 25 MW HFO Wartsila power plant, with an additional 10 MW of diesel, both of which Kinross own, Aggreko said.

“The diesel technology was ageing, very inefficient and prone to regular breakdowns, which was incurring Kinross huge maintenance costs,” Aggreko explained.

Furthermore, the company had recently completed phase one of an expansion of the mine. This included the installation of a new SAG mill to increase the rock crushing capacity by 50% – from 8,000 t/d to 12,000 t/d – however, the power generation capacity had not been upgraded. This meant the redundancy available on site was significantly decreased once the mine expanded and heightened the risk of power failures.

The life of mine was expected to be at least another decade away in 2029 too, and, with the diesel price volatility impacting operations, Kinross needed to think about power for the mine over the longer term, as well as what it could do to alleviate the cost implications it was suffering, short term, Aggreko said.

It engaged Aggreko to explore the options.

To address the immediate issues, Aggreko offered a solution that was easy to integrate into the team’s current power mix, it said.

“Replacing the existing diesel plant with 13 MW of Aggreko’s HFO power meant we could reduce their reliance on diesel, and they could keep the old diesel sets as additional redundancy for emergencies,” the company said.

“We synchronised with their existing Wartsila HFO plant and integrated the systems smoothly with no interruptions to their operations – ultimately safeguarding production.”

With Aggreko providing a turnkey solution, the company didn’t need to worry about operating or maintaining this new plant, it said.

Delivering the plant on time was also crucial for Kinross, Aggreko said.

With eight months of planning, the contract was signed in June 2019. This requested Aggreko to deliver and commission the plant by the last day in November of the same year.

“Putting our deep experience of operating in Africa to use, specifically our knowledge of local importation and logistics challenges, we delivered the project not only on time, but also on budget,” Aggreko said.

Aggreko concluded: “Kinross have reliable, guaranteed power 24/7 to ensure their gold production is unaffected by power issues or further shutdowns, and it’s given them the breathing space and time to review longer-term power options for the remaining life of the mine.

“The solution we put in place to use HFO also made the fuel management easier using one fuel across both their existing Wartsila plant and the new plant, which was also more cost effective.”

Tasiast produced 391,097 ounces of gold equivalent in 2019, according to Kinross. For the second consecutive quarter, the mine achieved record quarterly production and a record average throughput rate of 16,100 t/d in the March quarter, as the mine continued to benefit from the phase one expansion.

The company is also in the middle of a phase stage expansion at the operation, which could see throughput capacity increase to 24,000 t/d by mid-2023.

ABB solution underwrites solar power plant installation at Kinross Tasiast

Aggreko stabilises power supply for Kinross at Tasiast gold mine