Tag Archives: Burkina Faso

Metso to deliver a high-capacity grinding mill for Bomboré gold mine expansion

Orezone Gold Corp has awarded Metso an order for an 18 MW SAG mill for the Phase II Expansion at its Bomboré gold mine in Burkina Faso.

Christoph Hoetzel, SVP, Grinding business line at Metso, said: “The Premier™ SAG mill to be delivered to Bomboré is part of our Planet Positive offering thanks to its energy efficiency.

“This high-capacity SAG mill, which will be one of the largest gear driven mills installed in Africa, is based on proven technology. It features an efficient LSS drive, and a Polymer Hydrostatic Shoe Bearing system, which significantly improves radial and axial bearing reliability and longevity. It is also equipped with the Metso MillSense™ mill charge sensor system, which helps to stabilise and optimise the grinding process to ensure reliable operation and increased throughput.”

In October 2023, Orezone released the results of an expansion study which will incorporate a 4.4 Mt/y hard-rock plant to the 5.9 Mt/y oxide plant for a total processing rate of 10.3 Mt/y – a significant increase in gold production at a low incremental capital cost, it says. First gold from the hard-rock plant is scheduled for the September quarter of 2025.

Metso says it offers the industry’s widest range of horizontal grinding mills, including Premier and Select™ mills. These mills, Metso says, can be easily integrated with its mill relining equipment and are supported by the company’s extensive services network to ensure optimisation during the mills’ lifetime.

Metso also offers a comprehensive mill linings range and relining services, with materials and designs optimised for each specific application.

Metso Outotec confirms Premier grinding mill order for West African’s Kiaka gold project

Australia-based West African Resources has awarded Metso Outotec an order for state-of-the-art comminution equipment worth €30 million ($32 million) to be delivered to its greenfield Kiaka gold project in Burkina Faso.

Metso Outotec’s delivery includes two Planet Positive Premier™ grinding mills with a total installed power of 27 MW, as well as Metso Outotec’s proprietary metal and rubber mill linings and spare parts.

Kiaka, an asset with 7.7 Moz of reserves and resources on its books, is West African Resources’ second gold mine in the country on top of its operating Sanbrado asset.

WAF’s feasibility study, released in August 2022, outlined pre-production capital costs of $430 million and a 2.5-year pre-tax pay back at a $1,750/oz gold price for the project. Kiaka was expected to operate over an 18.5-year life of mine, producing, on average, 219,000 oz/y of gold (on a 100% basis).

Matt Scully, Project Director, West African Resources, said: “We are pleased to again team up with Metso Outotec for this project. West African is in an exciting growth phase, as we aim to be a multi-project, producing more than 400,000 oz/y of gold in 2025.”

Oskar Gustavson, Technology Director, Grinding at Metso Outotec, said: “The Premier SAG mill to be delivered to the Kiaka project is one of the largest gear-driven grinding mills in the world with its 18 MW of installed power. The Premier ball mill has been designed to pair smoothly with the SAG mill. Both mills are equipped with fail-safe Metso Outotec Polymer Hydrostatic Shoe Bearing systems, significantly increasing reliability and reducing maintenance costs. We are delighted to work with West African Resources on this project.”

West African secures Lycopodium and Metso Outotec mills for Kiaka gold project

West African Resources Limited is heading towards construction at its 90%-owned Kiaka gold project in Burkina Faso, having registered strong funding interest, awarded an engineering, procurement and construction management (EPCM) contract and booked the mill package for the development.

Kiaka, an asset with 7.7 Moz of reserves and resources on its books, is the company’s second gold mine in the country on top of its operating Sanbrado asset.

WAF’s feasibility study, released in August 2022, outlined pre-production capital costs of $430 million and a 2.5-year pre-tax pay back at a $1,750/oz gold price for the project. Kiaka was expected to operate over an 18.5-year life of mine, producing, on average, 219,000 oz/y of gold (on a 100% basis).

West African Executive Chairman, Richard Hyde, said strong competitive bids from its debt finance process supported the company’s targeted debt of $300 million for the project.

In the meantime, WAF has signed a notice of award with Lycopodium based on the engineering company’s priced proposal for the EPCM of a new carbon-in-leach treatment plant for Kiaka. This award incorporated Lycopodium’s early commencement of the engineering and procurement portion of the contract to complete the engineering and tendering of the long-lead mill package.

Lycopodium was also the contractor on the Sanbrado construction project.

In line with this, Lycopodium and WAF have undertaken a competitive tender process for the supply and delivery of the SAG and ball mill package for Kiaka.

Following the evaluation of tenders, the company selected Metso Outotec to supply the 18 MW SAG mill and 9 MW ball mill. Metso Outotec also provided the SAG and ball mills at Sanbrado (construction of the comminution circuit, pictured). WAF has signed the order with Mesto Outotec, which contains a firm pricing and delivery schedule for the mill package components that fits well into the Kiaka construction schedule, it said.

The mining company says it has mobilised earthworks equipment to the Kiaka project site. The initial areas to be cleared include the permanent camp area and the process plant area. Access road upgrades are also planned to be undertaken during the current dry season.

The construction schedule for Kiaka remains on track, with major works expected to commence in the March quarter and first gold in 2025.

WAF says it also remains on target to meet 2022 production and cost guidance of 220,000-240,000 oz of gold produced at an all-in sustaining cost of less than $1,100/oz.

West African Resources spells out Kiaka gold mine potential

West African Resources has released the results of a feasibility study for its 90%-owned Kiaka gold project in Burkina Faso, heralding a potential open-pit mining operation that can support a processing plant throughput of 8.4 Mt/y.

Kiaka is 140 km southeast of Ouagadougou, and 45 km south of the company’s existing Sanbrado gold mine.

The Kiaka mining study is based on conventional open-pit mining methods, with run of mine ore being directly fed to the crushing circuit. Mining operations will use a combination of 140 t (Cat 6015) and 230 t (Cat 6020) hydraulic excavators matched to 95 t dump trucks (Cat 777s).

Drill and blast will be required from near surface, with the parameters selected based on the relatively hard rock mass qualities and the required selectivity for mining of the ore. Given the broad mineralised zone, a portion of the blasting will be able to be undertaken on 10-m benches with more selective zones blasted on 5-m benches, the company noted. As such a combination of top hammer (Sandvik Panterra DP1500) and downhole hammer (Sandvik Leopard DI650) capable blast hole rigs will be employed.

To achieve the targeted processing rate, a total material movement averaging 21 Mt/y is required for the first seven years of the production schedule. With the pit staging deferring waste movement, this increases to an average of 35 Mt/y for the next six years of production before reducing to an average of 15 Mt/y for the remainder of the mine life.

The production profile is suited to an initial fleet of 2 x 230 t excavators and 1 x 140 t excavator matched to 95-t class trucks. The fleet will increase to 3 x 230-t excavators with 2 x 140-t excavators for the higher production requirement. Further work to investigate bulk mining scenarios and optimise fleet selection will be conducted, with further refinement of the drill and blast parameters also being undertaken in conjunction with fleet optimisation.

Kiaka’s free-milling gold ore is intended to be processed through a conventional single stage gyratory crushing and semi-autogenous ball mill crusher (SABC) milling circuit followed by carbon-in-leach (CIL) processing. Extensive metallurgical test work indicates Kiaka will deliver life of mine gold recoveries of 90% at a nominal 100-micron grind size.

Following review of the option studies the company selected the following major equipment:

  • Primary gyratory crusher – a Metso Outotec Superior™ MKIII 54-75;
  • SAG mill – 18 MW; and
  • Ball mill – 9 MW

The crusher can achieve 8.4 Mt/y for the design blend at 65% availability. At a 70% loading, the throughput rate ranges from 9.2 Mt/y to 10.2 Mt/y on the design blend. The selected mills also have higher than typical design margin for the nameplate throughput rate with modelling conducted by OMC showing the selected comminution circuit is capable of a throughput of:

  • 8.4 Mt/y (1,050 t/h) for 100% fresh ore feed when the 80th percentile ore characteristics are used;
  • 9 Mt/y (1,125 t/h) for 100% fresh ore when modelled at the average (50th percentile) ore characteristics;
  • 14 Mt/y (1,750 t/h) for 100% oxide ore feed; and
  • 10 Mt/y (1,250 t/h) for a blended feed of 23% oxide and 77% fresh ore.

On a 100% basis, life of mine (18.5 years) production is scheduled to come in at 219,000 oz/y of gold.

West African Executive Chairman and CEO, Richard Hyde, said: “Kiaka will access power from the Burkina Faso grid predominantly supplied by low-carbon hydroelectric power from Ghana and the Ivory Coast with large Burkina Faso low-carbon solar projects planned to come online early in the mine life to supplement the grid.”

Hyde says WAF will investigate expanding Kiaka to plus-10 Mt/y through the addition of secondary crushing and debottlenecking the process circuit, as well as evaluating tenders for key major equipment received during the feasibility study, which had ranged widely in price and delivery lead times.

“There remains scope to reduce the capital expenditure and cost contingencies on this equipment, as well as shorten the lead times,” Hyde said. West African Resources is also looking at an owner-mining versus contractor (the current plan) study looking to lower mining costs and VAT working capital.

Voltvision brings energy efficiency enhancements to Endeavour’s Hounde mine

Voltvision, the high voltage (HV) electrical data analytics business, has announced the successful completion of Phase 1 of what it says is a pioneering energy efficiency and operational enhancement project at Endeavour Mining’s Houndé Mine in Burkina Faso.

The results of this initial phase have proved so constructive that Voltvision has been commissioned to roll out the project to all of Endeavour Mining’s mines and development projects across West Africa, it said.

This project hinges on Voltvision’s big data software solution, a program that has been designed by mining specialists and engineers to optimise energy consumption and improve predictive maintenance on all high voltage equipment used on mine sites. This software is coupled with a data extraction cube, a secure ‘plug-and-play’ analytics device installed on a mine’s network. This device extracts and transmits hundreds of energy-related data points to the cloud-based software using Wi-Fi /4G networks, Voltvision explained.

Manoli Yannaghas, Co-Founder and Managing Director of Voltvison, says: “The Phase One roll out of this project was intended to provide high resolution data extraction in support of existing data systems presented in mobile- and PC-based dashboards. This allowed the mine’s technical team to monitor incoming grid power quality and the power quality across the Houndé power system. It has also allowed the accurate recording and logging of power usage as well as the movement from source to point of use again across the whole HV and MV networks.

“Phase 1 of the project commenced in December 2021 when the Cube device was remotely installed across Hounde’s high voltage electrical network, with assistance from the Endeavour team. The ‘plug-and-play’ nature of the device allowed the project to commence with minimal hassle and zero downtime in production.

“In the four months since this installation, a wide range of data points, numbering more than 200 individual points, have been collected and analysed. Early analysis of this data has facilitated a clear and comprehensive understanding of how the mine’s electrical network is behaving and how power is utilised in real time. This has made it possible for the Endeavour team to identify hidden problems and inefficiencies and understand what changes are required to achieve greater energy efficiency across the entire operation. The correction of such efficiencies can deliver quick cost savings and CO2 reduction as well as edging closer to operational excellence.”

The data recorded in this initial phase is a solid foundation for Phase 2, which is due to commence in May, he added.

“Phase 2 is intended to identify further power savings opportunities; develop early warning mechanisms for grid outages; and extract demonstrable Scope 1 and 2 GHG emission numbers. Voltvision will also provide highly accurate asset management services on capital equipment using algorithms it has developed with leading machine learning universities to provide advanced warnings of performance changes and fault development.”

Voltvision’s electrical management software is in the process of being rolled out across the rest of Endeavour’s operations, as mentioned.

Yannaghas concluded: “Through this initial Phase 1, we have formed an excellent working relationship with Endeavour Mining and are exceptionally pleased with the results produced thus far. We look forward to further engagement and assisting the company in optimising its HV electrical asset base, realising cost savings and facilitating the decarbonisation of its mine and project portfolio.”

Second Gekko InLine Leach Reactor heads to West African Resources’ Sanbrado mine

Gekko says a second InLine Leach Reactor (ILR) has been ordered by West African Resources for its 90%-owned Sanbrado gold mine in Burkina Faso.

The order is one of several to have emerged on the back of strong gold prices, with interest from a range of milling operations across the globe including Russia, North America, South America and Africa, Gekko says.

First developed in 1997, the ILR has provided an alternative from traditional physical separation steps, such as using recovery tables, into a lucrative chemical separation process.

It offers superior recoveries in a proven, high efficiency, safe and highly secure system, according to the company.

Available as a completely automated batch model for processing high grade gravity gold concentrates, the ILR can also be configured as a continuous model for treating high throughput gold, silver and complex sulphide concentrates from InLine Pressure Jigs and flotation circuits.

“The ILR’s innovative design and unparalleled flexibility in gold and silver leaching chemistry is providing cost and production benefits to operations across more than 40 countries across the globe,” Gekko said.

Construction on Sanbrado commenced in late 2018, with first gold poured in March 2020, six months ahead schedule and $20 million under budget.

West African anticipates Sanbrado will produce between 250,000-280,000 oz of gold at all-in sustaining costs of $720-800/oz.

The company says: “The estimated operating costs for the project highlight that the project will be a conventional, low cost and high margin operation. This is a result of high grade ore from M1 South and the significant proportion of oxide and transition material in the mine schedule and the free milling nature of all ore types (average life of mine recovery of 93%), low reagent consumption and a high component of gravity recoverable gold.”

Howden delivers mine cooling plant at Roxgold’s Yaramoko mine

Howden says it has successfully delivered the first phase of an 8 MW surface bulk air cooling plant for Roxgold’s Yaramoko gold mine in Burkina Faso.

The Yaramoko Mine Complex is in a remote region of Burkina Faso, 200 km southwest of Ouagadougou.

The cooling plant is designed to deliver a maximum of 190 cu.m/s of chilled downcast ventilation air, with the air cooled from a design ambient temperature of 25.8°C, down to 15°C.

The plant comprises an open-spray vertical bulk air cooler located on top of the shaft collar, centrifugal chillers and conventional cooling towers, Howden explained.

Plant design and construction were started at the beginning of 2020 during the early onset of the COVID-19 pandemic, and, despite a challenging environment, Howden successfully delivered the project’s first phase in May.

Howden said: “This latest project continues to positioning Howden as a process and system specialist to design, supply and install mine cooling systems. Howden has a technology-neutral approach whereby technology options are offered which best suits customer’s technical and commercial requirements.”

The Yaramoko Mine Complex, which consists of two underground operations, delivered production of 35,308 oz of gold in the March quarter, Roxgold reported in May.

Orezone ties up LNG and solar power options for Bomboré gold project

Orezone Gold Corp’s Bomboré gold project is to become the first mine in Burkina Faso to use LNG to power its operations after the Vancouver-based company signed a Power Purchase Agreement (PPA) with Genser Energy Burkina SA for the supply of “clean energy electrical power” to the project.

Under the PPA, Genser will use liquefied natural gas (LNG) as its main fuel, augmented with a staged solar plant, Orezone said. A fixed rate energy tariff will apply over the life of mine oxide operation with a fixed rate tariff to be negotiated for the additional energy demand upon commissioning of the sulphide processing circuit expected in Year three of commercial production.

The power plant will consist of 6 2.5 MW LNG generators with four 2.6 MW diesel back-up units. This configuration is sized for the initial oxide operation and the planned sulphide expansion, the company explained. At the same time, a solar photovoltaic plant, up to 14 MWp, is to be installed in stages with an 11 kV powerline to connect the gas and backup diesel generators, and solar plant.

Genser is to design, permit, finance and install all power generating equipment and associated infrastructure including LNG storage and diesel storage terminals. It will also be the operator and owner of the power plant facility.

Patrick Downey, President & CEO of Orezone, said: “We are extremely excited to be the first mine in Burkina Faso to use a LNG and solar hybrid power supply. Besides being an excellent cost-effective choice for Bomboré, we also see this new power solution as being a very positive step for the Burkina Faso mining and electricity generating sectors. LNG power systems, coupled with solar, will enable energy intensive industries such as mining to reduce fuel consumption, decrease energy costs, and significantly cut greenhouse gas emissions.”

He added: “This life of mine fixed cost agreement for clean energy from Genser provides power cost certainty over life of mine oxide production at Bomboré and provides an excellent platform for project expansion and growth.”

The Honourable Dr Bachir Ismael Ouedraogo, The Minister of Mines and Energy for Burkina Faso, said: “Having the first LNG plant at a mining operation is a great step forward for the industry and we congratulate Orezone in this regard. As a government, we continue to support clean energy alternatives that provides a platform for sustainable growth and benefits our communities.”

Alongside the announcement of the PPA, Orezone said that significant progress had been made at Bomboré during the first two quarters of the year. Engineering is now approximately 30% complete and on schedule, with design and bulk quantities from this work trending favourably against the quantity estimates used in the 2019 feasibility study.

Procurement is well advanced with firm orders placed for most mechanical and electrical equipment with purchase costs generally below budget estimates, it added.

In January, the company appointed Lycopodium Minerals Pty Ltd as the project’s EPCM contractor, while, in February, Sila Equipement ET BTP SA was named as its open-pit mining contractor.

Meanwhile, bulk materials including concrete reinforcing bar and embeds, CIL tank platework, structural steel and platework, HDPE liner, and overland piping have also been ordered with costs also trending within budget, Orezone said.

Off-channel reservoir mining, earthworks for the plant site area and tailings storage facility are rapidly advancing, and the award of the contracts for concrete installation and CIL tank erection and overland piping are imminent, it added.

Orezone’s 2019 feasibility study on Bomboré envisaged a 5.2 Mt/y throughput operation able to produce, on average, 117,760 oz of gold over a 13-year mine life where both oxide and sulphides would be mined and processed. The project remains on track for first gold pour in the September quarter of 2022.

B2Gold weighs use of dual fuel haul trucks at Kiaka project

B2Gold’s strong growth path in Africa looks like continuing into future years after the company laid out preliminary plans to develop a mine in Burkina Faso that could use on-site hybrid power in addition to dual fuel haul trucks burning a mix of diesel fuel and LNG.

The Vancouver-based miner reported record total production in 2020 of 1.04 Moz of gold, with its Fekola (Mali) and Ojikoto (Namibia) mines contributing some 790,559 oz. It is guiding for 970,000- 1.03 Moz of gold in 2021.

In announcing these results, the company also provided an update on its Kiaka gold project in Burkina Faso.

This project, which B2Gold owns 81% of, currently hosts 4.25 Moz of indicated resources on a 100% basis at an average grade of 0.95 g/t Au. It also comes with 900,000 oz of inferred resources at 0.99 g/t.

The company is currently updating the existing feasibility study for the Kiaka project, reflecting, it says, the potential for improved economics resulting from lower fuel prices, alternative power options and a higher gold price.

A mineral resource model using additional drill results and revised model interpretations was completed in December, with the study set to leverage the new resource and several new concepts to reduce costs. Included among these new concepts is a plan to use a liquid natural gas (LNG) hybrid power plant combined with solar power, and dual fuel haul trucks that burn a mix of diesel fuel and LNG.

A larger processing plant size of 12 Mt/y is also being considered for this updated feasibility study, it said.

B2Gold expects to have an internal decision document completed by the end of March, with an updated feasibility study completed by the end of June.

Sila Equipement to take on contract mining task at Orezone’s Bomboré gold project

Orezone Gold Corp has selected Sila Equipement ET BTP SA as its open-pit mining contractor for the Bomboré gold project in Burkina Faso.

This follows the January appointment of Lycopodium Minerals Pty Ltd as the lead EPCM contractor for the project.

Sila, a Burkinabé company, will initially have a contract scope that covers the mining of the Off-Channel Reservoir (OCR) pit, as well as the upfront establishment of mine site services (maintenance workshops, wash bays, warehouse, ablutions and accommodations, offices, and communications), the clearing and grubbing of the OCR footprint including topsoil relocation, as well as pit dewatering and haul road maintenance.

Orezone said mining of the OCR is an important milestone given that the pit will serve as the main water storage facility during operations.

“The mobilisation of Sila will ensure that the OCR and its related infrastructure will be ready well in advance of the onset of the 2022 rainy season,” the company explained.

Orezone says it is working in partnership with Sila to finalise certain key terms under the long-term mining contract.

Patrick Downey, President and CEO, said: “With the project financing now in place, we are rapidly advancing the engineering, procurement, and construction of the project. The early award of the mining contract will allow our project to remain on schedule.

“I am pleased that Sila, a local contractor, has been awarded this work which speaks to the depth and continued growth of the mining service industry in Burkina Faso. The company’s selection of Sila was made after a competitive tender and due diligence process including a review of safety and operational performance in free-dig oxide operations such as Bomboré. Sila has demonstrated an excellent track record in other similar Burkina Faso mining operations.”

He added: “The proposed mining fleet is brand new equipment and will be operated by Sila’s highly experienced senior operations and maintenance team.”

Since the recent appointment of Lycopodium in January as the EPCM contractor, the company says it has rapidly advanced engineering and procurement activities, and made significant progress on refining the project construction timeline. The company’s key procurement and site-based activities in the upcoming months will be focused on the following:

  • Pre-production mining to commence in March 2021;
  • Ball mill order (a critical long lead item) to be placed in March 2021;
  • Award of power plant contract in March 2021; and
  • Site-wide bulk earthworks to commence April 2021.