Tag Archives: Zimbabwe

More Weba chutes set to arrive at Zimbabwe platinum mine

Comminution of minerals, Mineral processing, Mining equipment, Precious metals, , , , ,

South Africa-based Weba Chute Systems is set to provide 10 more of its custom engineered transfer chutes for the expansion of an underground crusher station at a platinum mine in Zimbabwe.

Overseeing the contract for Weba Chute Systems is Project Manager, Ted Cruikshank, who explains that the design, manufacture and delivery of the units is already 80% complete. Over the past 20 years, the company has installed approximately 70 chutes for this customer.

“The chutes being supplied in this latest contract will feed run-of-mine material from the ore pass to the underground crusher, as well as from the crusher to the outgoing conveyor,” Cruikshank said. “This has involved designing and building chutes ranging in height from two metres to six metres.”

Before the crusher, the chutes take large material of up to 650 mm in size from a vibrating feeder, at a maximum tonnage of 1,100 t/h. Other chutes take the feeder’s undersize, which is smaller than 180 mm in size, at 550 t/h. Some of the chutes will also be used in conveyor-to-conveyor applications; these feed 1,500-mm wide belts with up to 1,350 t/h of material with a maximum lump size of 250 mm.

“The abrasiveness of platinum ore makes our chute design philosophy – based on the cascade system – very important,” Cruikshank said. “Our use of dead boxes on the inside of the chute creates a layer of ore for the moving material to flow over – thereby extending the wear life of the chute itself.”

Replaceable lips on the dead boxes become primary wear parts, which can be easily and quickly swapped out at the necessary intervals. By controlling the flow of the mined and crushed material, the chutes facilitate smoother transition and central loading onto conveyor belts, in turn reducing wear, damage and spillage, the company explained.

“The chutes also include inspection doors for easy access during maintenance,” Cruikshank said. “To promote optimal uptime for the customer, we are also including a spare set of wearing lip liners for each chute. These are vital for securing the material layer, while ensuring that the dead box itself is protected from undue wear.”

Weba Chute Systems’ agent in Zimbabwe, the locally owned firm Hilmax, will supervise the installation of the chutes.

Rio Tinto’s Richard Bay Minerals to go solar with help of Voltalia, BEE partners

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Rio Tinto’s 74%-owned Richard’s Bay Minerals (RBM) business will soon be supplied with renewable solar power through an agreement with international energy company Voltalia and local Black Economic Empowerment (BEE) partners, for its operation in KwaZulu-Natal, South Africa, Rio says.

Under the agreement, Voltalia will begin construction of the Bolobedu Solar PV renewable energy project in 2023, at a site in the province of Limpopo. The power plant is scheduled to be complete by 2024 and will deliver an annual generation capacity of up to 300 GWh. It will feed into the national power grid to supply RBM’s smelting and processing facilities through a “wheeling agreement”.

The renewable power supply is expected to cut RBM’s annual greenhouse gas emissions by at least 10%, or 237,000 t/y of CO2e, Rio says.

Rio Tinto Minerals Chief Executive, Sinead Kaufman, said: “The agreement, which is a first step towards reducing RBM’s carbon emissions, is a major milestone and one that is in line with Rio Tinto’s decarbonisation strategy. As this solar energy project progresses, we will continue exploring additional renewable solutions that further reduce our emissions in South Africa and make Richards Bay Minerals a contributor to our net zero commitment.”

Voltalia CEO, Sébastien Clerc, added: “We are very pleased to support RBM in its decarbonisation journey. The Bolobedu photovoltaic power plant will be our biggest project in Africa, after performing construction of a series of other solar plants for us or for clients, in the continent (Zimbabwe, Burundi, Tanzania, Kenya, Mauritania and Egypt). This project is the first of our South African large solar-and-wind portfolio under development, in areas with grid connection available, that will be ready to support our clients to overpass the actual energy crisis with affordable, clean and stable electricity.”

Voltalia will work to ensure the Bolobedu Solar PV project creates local employment opportunities for the surrounding communities. A total workforce of more than 700 people is expected during construction, with a workforce of around 50 people once the plant becomes operational.

The project will also provide skills development opportunities for members of the surrounding communities, and a bursary program for young local learners. In support of South Africa’s growing renewable energy sector value chain, Voltalia will work to source its goods and services locally.

The Bolobedu Solar PV power plant will be 51% black-owned through BEE partners, with a minimum 10% stake going to black women, while the host community will also have a participation.

Sixth Wave to deploy IXOS gold extraction and purification tech in Zimbabwe

Environmental, Metallurgy, Mineral processing, Mining services, Precious metals, Sustainable mining, , , ,

Sixth Wave Innovations Inc says it has signed a three-phase test and implementation contract that will field its patented IXOS® molecular imprinted polymer for extraction and purification of gold and silver at Magnus Resources’ majority-owned Penhalonga gold mine in Zimbabwe.

Additionally, Magnus Resources plans to build and deploy three smaller processing plants to assist regional artisanal mining groups in Zimbabwe. The goal is to assist and direct artisanal mining operations from dangerous and environmentally destructive practices involving mercury amalgamation, Sixth Wave says.

IXOS has been demonstrated to capture up to 99% of gold from cyanide leach solutions in laboratory and mine site testing where the data was analysed by the mine operator, representing a material increase relative to activated carbon, which recovers between 85% and 95% of the gold, as reported by potential mining customers of IXOS. Additionally, the increased selectivity of IXOS results in the capture of fewer other competitive base metals, Sixth Wave says.

The project with Magnus will be carried out in three phases.

Phase 1 of the project will commence immediately with Magnus sending ore samples to Sixth Wave’s laboratory for extraction and recovery testing. This phase is expected to complete within six-to-eight weeks after receipt of samples and will provide the metallurgical information required for Phase 2. The contract specifies $49,240 for this phase.

Phase 2 of the project will begin upon completion of the testing and includes a mine site visit to evaluate existing infrastructure. Further, Sixth Wave mining experts will obtain necessary data required for the pilot circuit to include historical metallurgical test data, test results from its laboratory analysis, geological data, existing infrastructure and project throughput of 5 t/h. Phase 2 will focus on pilot plant process design, engineering and implementation for gold recovery from oxides at an estimated cost of $26.1 million. The contract contemplates expansion of the process capacity and testing and implementation of additional capability to deal with the transitional and refractory ore.

In addition to the plant for Penhalonga, Phase 2 activities will include testing, engineering design, and delivery/commissioning of three portable VAT leach adsorption/desorption/recovery plants that are capable of processing 100 t/d of ore. The portable plants will be placed in strategic regions of the country to service readily available ore from small and medium sized artisanal miners. It is estimated that each plant will cost between $7.8 million and $11.5 million depending on actual configurations, with currently three plants planned.

Completion of the initial implementations will launch Phase 3 to address the testing and optimisation of extraction for the transitional and refractory ore present at the mine. This work has not yet been costed and scheduled.

Sixth Wave will name Magnus as the exclusive distributor for IXOS®-Au in Africa and the countries that comprise the Gulf Cooperation Council (GCC) as per the initial memorandum of understanding. Term aspects and finalisation will not be addressed until completion of Phase 1.

Nicol Newton, Vice President, Sixth Wave Mining Division, said: “We are very excited about this collaboration and bringing our advanced technology to the mining industry on the African continent and beyond with Magnus Mineral Resources (PVT) Limited. I have been involved in several mining operations including design and commissioning on the continent and within the GCC. My prior experience allows the Sixth Wave team to have a foundational understanding of the challenges and requirements so that we can help ensure the success of the Magnus projects.”

Tanaka Solomon Nyabadza, Managing Director, Magnus Mineral Resources, said: “Magnus Mineral Resources (PVT) Limited is extremely satisfied with the technical depth and analysis that has been provided by Sixth Wave to get us to the point that we can launch the project. We are looking forward to the initial testing data and further defining the design and implementation specifications to maximize the profitability of our endeavours.”

Magnus Mineral Resources is a Zimbabwe-based company focused on acquisition, exploration, development, mining, processing, refining, metallurgy, trading and consultancy with extensive experience in gold, diamonds, lithium and rare earth minerals.

Zimplats to boost PGM mine, concentrator output in Zimbabwe

Mineral processing, Mineral project development, Precious metals, , , , ,

Zimplats’ Board of Directors has signed off on several new projects at its platinum group metal operations in Zimbabwe, including the building of a new mine, expansion of its in-country processing capacity and the addition of a solar plant to augment power supplies.

The board approved an overall capital investment strategy with a budget of $1.8 billion to be implemented over a 10-year period beginning in 2021, with $1.2 billion already approved for implementation.

Zimplats, a member of the Implats Group, is focused on production of platinum group and associated metals from the Great Dyke in Zimbabwe. It currently operates four underground mines and a concentrator at Ngezi, while the Selous Metallurgical Complex, 77 km north of the underground operations, comprises a concentrator and a smelter.

These projects, including those that are currently in process of being approved, will concentrate on:

  • Maintaining current production levels through mine replacements and upgrades ($516 million);
  • Expanding production levels through growth projects, including the development of a new mine and increased processing capacity, which will boost nameplate capacity from 6.7 Mt/y to 8.8 Mt/y and in-country processing capacity to 380,000 t/y of concentrate, and the establishment of an abatement facility to mitigate sulphuric dioxide emissions emanating from the current and expanded smelting capacity ($969 million);
  • Refurbishing the mothballed base metal refinery, to further beneficiate converter matte ($100 million); and
  • Investing in a 185 MW solar plant to augment power supplies and enhance environmental, social and governance performance metrics to maintain Zimplats licence to operate ($201 million).

These projects, the company said, are expected to be funded by internally generated resources.

Caledonia Mining heads for Central Shaft commissioning at Blanket gold mine

Mine operation news, Mine shafts and equipment, Mineral project development, Mining services, Precious metals, , , , , , ,

Caledonia Mining says it has fully equipped the Central Shaft from its base to the surface collar at the Blanket gold mine in Zimbabwe, with commissioning on track for the March quarter of 2021.

This milestone has been completed considerably below budget and within a time frame to underpin the company’s expectation of delivering production of 80,000 oz of gold in 2022, it said.

The Central Shaft project, which extends Blanket’s life of mine to the current time horizon of 2034, was initially slated to reach a depth of 1,089 m, however, was extended to 1,204 m.

Steve Curtis, Caledonia Chief Executive Officer, said: “Shaft sinking is widely regarded as one of the most dangerous activities in mining and I am proud to report that over more than five years the crew achieved 1,850 fatality free shifts to date with only two loss time injuries (LTI) and achieving more than one million LTI-free man hours worked since the last LTI.”

He added: “Central Shaft is one of the largest gold mining investment projects in Zimbabwe and will be transformational to our business: our target production is set to increase by 45% to 80,000 oz by 2022 while our long-term all-in sustaining costs are expected to drop to $700-$800/oz. Central Shaft will also position us to step-up our deep level exploration which, if successful, may extend Blanket’s life of mine, which is currently to 2034.”

The capital cost of the project to date is around $60 million, compared with initial sinking contractor quotes received of about $100 million. The shaft work was completed by Blanket crews with supervision from Sinking Engineering Mining Construction, Caledonia said.

Voltalia to build 12 MW solar plant at Caledonia’s Blanket gold mine

Environmental, Mine operation news, Mining services, Power supply for mines, Precious metals, Sustainable mining, , , , , ,

Caledonia Mining, having raised the required funds to invest in the construction of a solar power plant to supply electricity to the Blanket gold mine in Zimbabwe, has appointed Voltalia as the contractor for the project.

Voltalia is an international renewable energy provider and has considerable experience in the delivery of renewable energy projects including the development, construction, operation and maintenance of solar power plants. It is already active notably in Burundi, Malawi and South Africa, according to the company.

Caledonia and Voltalia have agreed an initial design phase for the project after which, subject to the conclusion of an engineering, procurement and construction (EPC) contract, procurement and construction are expected to begin with current indicated commissioning for the 12 MW solar plant in the December quarter of 2021.

On completion, the solar plant is expected to provide approximately 27% of the mine’s total electricity demand, significantly reducing the risk to the mine of any further deterioration in the quality of grid power which would necessitate increased use of diesel generators (which are substantially more expensive than grid power), the company said, adding that the plant will also reduce Blanket Mine’s environmental footprint.

Weba custom-engineered chutes cut the dust at platinum mines

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Weba Chute Systems says it has been able to demonstrate to platinum mining customers how its custom-engineered chutes significantly reduce dust at transfer points.

Using the latest dust measuring technology, the company has carried out tests at mines in South Africa and Zimbabwe to compare the impact of Weba designs on material flow and dust levels, Izak Potgieter, Systems Manager at Weba Chute Systems, said.

At the site in Zimbabwe, considerable dust levels were created at bunker discharge chutes. Material of up to 500 mm in size was moving through at a rate of 600 t/h.

“The material flow was the biggest factor generating dust in the conventional chute, as material was not flowing as evenly as it should,” Potgieter says. “This created a lot of energy for the dust particles to expand into the surrounding atmosphere.”

The installation of the Weba chute – with its engineered design for optimal flow control – reduced the dust levels by about 40%, according to the company.

“By controlling the velocity of material, the design not only cuts dust creation but also reduces impact and wear for increased productivity and less maintenance downtime,” Weba said.

At the South Africa operation, the tests were conducted at a transfer point in the milling plant where an average tonnage of 190 t/h was being moved. Despite the use of water sprays, the existing chute was still creating considerable dust. The installation of the Weba chute was able to reduce dust levels by 15%, according to the company.

“Dust levels have shown to have a serious impact on human health, especially smaller particle sizes of 0.3 micron,” Potgieter says. “Health effects of dust relate mainly to particle size and dust may contain microscopic solids or liquid droplets that are small enough to get into the lungs and cause serious health problems.”

Spores and contaminants associated with dust and aerosol can also adversely impact human health, causing a range of issues from respiratory infections to toxic exposure, according to Weba.

DRA Global to help debottleneck Anglo American Platinum’s Unki PGM concentrator

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DRA Global says it has been awarded an engineering procurement and construction management contract to expand Anglo American Platinum’s Unki platinum group metals concentrator, in Zimbabwe.

The engineering company was previously enlisted to carry out a feasibility study on the expansion, referred to as the “debottlenecking” project by Anglo American Platinum, and will now help increase throughput capacity to 210,000 t/mth, it said.

The Unki concentrator, built in 2010, can currently treat up to 180,000 t/mth according to Anglo American Platinum. It processes material from the Unki mine, one the world’s largest PGM deposits outside of South Africa, the miner says.

Anglo American Platinum, in its 2019 results released earlier this year, said it had signed off on the R700 million ($39 million) debottlenecking project and expected commissioning to be completed in the September quarter of 2021.

Unki has steadily been ramping up production in recent years. In 2019, it produced a record 202,000 oz of platinum group metals, up from 193,000 oz in 2018 and 166,000 oz in 2017.

Caledonia breathes new life into Blanket gold mine

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Caledonia Mining says it has successfully installed and commissioned a new oxygen plant at its 49%-owned Blanket gold mine in Zimbabwe.

The new oxygen plant is expected to improve metallurgical recoveries and reduce cyanide consumption at Blanket. Test work indicates the plant will improve overall metallurgical recoveries at Blanket to around 94%, up from the 93% average recorded for 2019 so far.

Steve Curtis, Caledonia Chief Executive Officer, said the oxygen plant commissioning was the latest in a series of investments to increase production and improve operating efficiency at Blanket as it looks to reach 80,000 oz/y capacity by 2022. One of the other projects that will contribute to this increased output is the sinking of the Central Shaft, which was completed earlier this year.

Curtis said: “The new oxygen plant will provide up to 6 t of improved oxygen supply to the Blanket carbon-in-leach plant, which is expected to increase recoveries to approximately 94%.

“We also anticipate that the oxygen plant will result in slightly lower operating costs as cyanide consumption is expected to be reduced as a result of the improved oxygen supply; and the operating costs of the new oxygen plant are predicted to be lower than those of the previous two tonne plant.”

Blanket produced 54,512 oz of gold in 2018 and is expected to produce 53,000-56,000 oz in 2019.

Shaft sinking complete at Caledonia Mining’s Blanket gold mine

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Shaft sinking at the new Central Shaft at Caledonia Mining’s 49%-owned Blanket gold mine, in Zimbabwe, has been completed, the company reports.

The Central Shaft project has been in progress since early 2015, with Caledonia spending some $44 million sinking a new shaft from surface to a depth of over 1,200 m.

Sinking of the shaft was predicated on increasing gold production to 80,000 oz/y of gold, compared with 54,512 oz produced in 2018 and the 53,000-56,000 oz expected in 2019.

The project now moves to the equipping phase prior to commissioning, which is expected during the September quarter of 2020, the company noted. Production from Blanket mine is then expected to progressively increase to the target 80,000 oz/y of gold from 2022 onwards.

“The company expects the increased production, combined with economies of scale and lower future capital investment, will result in significant increases in Caledonia’s profit and distributable cash,” it said.