Tag Archives: diamonds

African Star appoints new mining contractor at Oena diamond mine

Southstone Minerals Ltd’s 43% owned subsidiary, African Star Minerals, has entered into a contract mining and diamond recovery agreement with Oryx Mining for the Oena diamond mine, in South Africa.

Oryx, at its own cost and expense, will provide and maintain all the plant and equipment as required to perform the mining services, Southstone says.

The diamonds produced by Oryx will be sold via a designated tender facility in South Africa and 80% of the gross income of net diamond sales, less commission, will be paid to Oryx for the duration of the 36-month agreement, the company explained. For any individual stones recovered with a gross selling price, less commission, of greater that ZAR10 million ($664,529) Oryx will be paid 70% of the gross income.

Oryx specialises in the processing of alluvial diamond deposits in South Africa and the operation is currently targeting to operate 24 h/d, six days a week with total headfeed capacity of 200 t/h. Equipment and road building is ongoing, and it is expected production will commence in May 2022.

The contract award follows the conclusion of mining by another contractor, Bluedust 7 Propriety Ltd.

Oena consists of an 8,800-ha mining right located along the Orange River in a well-established alluvial diamond-mining province that produces high quality and large sized diamonds.

TOMRA continues to build ore sorting Insight across mining space

Some 18 months after launching TOMRA Insight to mining customers, the cloud-based data platform is making inroads across the North American mining sector, Harold Cline and Jordan Rutledge told IM on the side lines of the MINEXCHANGE 2022 SME Annual Conference & Expo in Salt Lake City recently.

TOMRA rolled out the subscription-based service to mining back in late 2020, with one of the early adopters being the Black chrome mine in South Africa, one of two mining projects that form the basis of the Sail Group’s plans for long-term sustainable chrome production.

TOMRA Insight, the company says, enables sorting machine users to improve operational efficiencies through a service that turns these machines into connected devices for the generation of valuable process data.

Cline and Rutledge, both TOMRA Sorting Area Sales Managers for North America, said numerous customers were now taking advantage of TOMRA Insight across the region, with many more interested in leveraging the continuous data streams coming off a web-based portal stored securely in the cloud.

TOMRA’s Harold Cline & Jordan Rutledge

“This is seeing mine managers able to tap into how operations are performing today, while tracking that against performance over the last day, week, month, quarter, etc,” Cline told IM. “With the help of our support network, these operations are able to achieve more consistent performance.”

With more customers signing up to TOMRA Insight and more data being generated, the pair were confident future iterations of the platform would be able to offer machine-learning algorithms that helped, for example, predict failures or highlight potential areas for operational improvements.

At the show, the pair were also highlighting the ongoing demand for TOMRA’s Final Recovery sorter, the COM XRT 300/FR, which, since launch, has been successfully deployed at the Letšeng diamond mine in Lesotho, owned by Gem Diamonds. The solution has gone on to be rolled out at other operations.

The introduction of the COM XRT 300/FR, TOMRA became the first company in the industry able to supply a full diamond recovery solution using XRT technology from 2-100 mm, with the unit delivering concentration factors of up to one million with limited stages and guaranteeing more than 99% diamond recovery, according to the company.

Outside of diamonds and sorter analytics, Cline was keen to talk up demand from the gold sector for the company’s sorters.

One of the key differentiators of its offering to the yellow metal space is the ability to scan the material with a multi-channel laser sensor. In an ore sorting setup that involves both XRT and LASER sensor-based machines, the TOMRA solution can remove particles containing sulphide minerals using XRT and subsequently leverage laser sensors to remove particles containing quartz and calcite.

TOMRA says its segregated option can potentially improve recoveries in quartz-associated gold applications thanks to a laser chute-based machine that analyses rocks from both sides. Other belt-based laser machines can only analyse a maximum of 40% of the rock’s surface, according to TOMRA.

“In the gold scenario, we are using XRT to sense and sort with sulphide minerals as a proxy,” Cline said. “At the same time, our laser scanner allows further separation capabilities through identification of minerals such as quartz and calcite.”

Vista Gold, which is developing the Mt Todd project in Australia, anticipates that this combined solution could eliminate approximately 10% of the run-of-mine feed to the grinding circuit, allowing the company to decrease the grind size and thereby increase recovery of the contained gold.

The COM XRT 300/FR offers a full diamond recovery solution

Cline added: “In North America, we have three projects in the gold space we’re working on at the moment that appreciate our unit’s ability to analyse the whole of the particle through our chute mechanism, as opposed to conveyor-based systems that can only analyse one angle of the particle.”

While TOMRA offers multiple sensors on its units through its modular platform, Rutledge said the company continues to have discussions on combining its solutions with other bulk sorting suppliers to further improve the process, naming prompt gamma neutron activation analysis (PGNAA) technology as one specific area of interest.

“We very often refer clients on to other companies when our solution may not match their brief,” she said. “At the same time, we have done some flowsheet work to include our solution with others currently on the market and believe it is only a matter of time before a combination of the two comes into a flowsheet.”

Weba Chute Systems solves choking problem at Botswana diamond mine

Weba Chute Systems has come to the rescue of a large Botswana diamond producer suffering from continuous chute maintenance with a customised solution that came with a 12-month guarantee.

This primary crusher discharge chute had been a headache for the company, with the crunch coming when, after considerable capital expenditure, the new conventional chute needed maintenance just six weeks after installation.

Hilton Buys, Regional Manager at Weba Chute Systems, said: “This could not continue and the mine needed a long-term solution which is why we believe they came to us for a proposal. Senior experts from our company visited the site to take a careful look at the conditions the chute needed to deal with, and we took our conclusions back to our design office.”

Among the challenges were large lump sizes in the ore stream, contributing to build-up of material in the chute and regular choking, Buys said. Also, while Botswana’s dry season is long, the rain that does fall causes considerable problems to the flow dynamics. The kimberlite on the mine – depending on which part of the pit it comes from – can become very sticky in wet weather, according to the company.

“We therefore had to pay particular attention to flow angles, and the design had to effectively accommodate both wet and dry conditions,” Buys said. The concept design – which included quick-release lips on dead boxes – was approved by the mine and the final design, manufacture and successful installation was conducted.

Adding to the complexity was that the feed end of the primary crusher was some 8 m below ground level, while the crusher itself stood about 10 m tall. The chute had to be positioned below the rock box, which stores the material from the crusher discharge, channelling the stream into the Weba chute at a transfer height of 9 m to the conveyor belt.

“The conventional chute also created excessive dust through uncontrolled rock velocity over this considerable transfer height,” Buys said. “By contrast, our chute’s controlled flow meant that the mine did not even have to apply its dust suppression system.”

After installation, Weba Chute Systems gave the customer a 12-month guarantee on this chute, as it does with all its new chutes. This guarantee, which comes with regular inspection reports, assures the customer that the performance will meet their expectations.

“These inspections allow us to monitor wear, so we can advise the customer on what action is required so that they can schedule maintenance and avoid unexpected downtime,” Buys said.

Installed in 2017, the chute is still operating with little maintenance, having been delivered at a highly competitive price compared to the one it replaced.

“Designing a long-lasting chute is not just about creating a box with some reinforcing where you think there will be wear,” Buys said. “It is an endeavour that must be scientific, based on in-depth analysis of material and flow conditions.”

Buys highlighted the importance of asking a range of technical questions about the specific application so the design answers those needs. The latest software and modelling tools are then applied by the Weba Chute Systems team to guide the most effective design.

WEC Projects looks to nature for Lucara Karowe sewage treatment plant

WEC Projects has secured a R3 million ($187,460) contract to supply a new sewage treatment plant for the expansion of Lucara Diamond’s Karowe diamond mine in Botswana.

The mine, near the village of Letlhakane in the eastern Kalahari Basin region of Botswana, is planning to cease open-pit activities by 2026 after which it will continue mining underground, extending its operational life to around 2040. More than 1,000 m above sea level, the mine operates in a region where temperatures average 35°C and water is scarce; so much so that the Government of Botswana has legislated mandatory water saving requirements for industry.

WEC Projects installed the original treatment plant in 2012 and will integrate the new system into the existing facility, increasing throughput from 100 cu.m/d to 150 cu.m/d to meet the requirements of an increase in the number of staff at the mine. While the treatment plant itself is a fairly standard installation, the mine requested a variation to the original project scope – a man-made natural reed bed wetland system that will provide a “polishing” phase to the treatment process, using natural organisms and filtration processes to further clean the wastewater, WEC Projects said.

Wayne Taljaard, Managing Director of WEC Projects, said: “This is a particularly unique feature for a mine as usually such reed bed wetlands are built for much larger installations such as municipal sewage treatment. The government’s mandate for water conservation has forced companies in Botswana to apply creative thinking to overcome the challenge of operating in an arid country.”

The main sewage treatment facility will consist of a WEC Projects Model A treatment plant, an extended aeration system using conventional activated sludge to process the sewage. The wastewater passes through a mechanical screen which removes solids and is then treated by a biological reactor which integrates anoxic, aerobic and clarification zones.

After treatment, the water will enter the reed bed wetland area where it will percolate through the reed bed allowing microorganisms to breakdown contaminants such as sulphur, heavy metals and chlorine. The water produced by this process, while not for human consumption, will be reused by the mine for applications such as irrigation and dust suppression, according to the company.

To create the wetland, a shallow dam will be built, its bottom to be filled with gravel and reeds planted. The water from the treatment plant will feed into the wetland area where nature will be left to take its course.

Taljaard added: “The reed bed solution offers a number of advantages for the mine as the effluent will be relatively odourless and is flexible enough to cope with fluctuations in input. It also requires little maintenance once it is up and running and will ensure that the mine remains within the constructs of the law.”

ALROSA looks to reclaim Aikhal tailings pit as part of 650 ha land restoration project

ALROSA plans to reclaim the tailings pit of processing plant No. 8 at its Aikhal Division by 2029 in a project worth over RUB2.5 billion ($34.3 million) that will seek to restore 650 ha of land and have it planted with pine forests, the diamond miner says.

The tailings pit is located 1.2 km southwest of the village of Aikhal (pictured) in the Sokhsolookh River valley in Yakutia, Russia. The decision to reclaim the facility followed the completion of mining at the Komsomolsky open pit and the closure of processing plant No. 8 at the end of 2020.

During the plant’s operations, tailings were stored in the tailings pit as a liquid slurry. In terms of environmental danger, the slurry belongs to the lowest hazard waste category (virtually non-hazardous waste or category 5 under the Russian Federal Law on Industrial and Consumer Waste), ALROSA says. The tailings pit was a key hydrotechnical facility ensuring water recirculation at the processing plant: after the slurry settled in the pit, clarified water was fed back into the plant to be re-used in processing diamond ore, the company explained.

The reclamation project will be implemented in two stages.

The first stage will include draining the pit and restoring a part of the original course of the Sokhsolookh River back to its natural state.

Later on, from 2025 to 2029, the tailings facility will be dismantled, and work will be carried out to improve the land, dig drainage ditches, install waterproofing, lay fertile soil and landscape the area. To achieve this, 160,000 Scots Pine seeds have been sown in 2021 in a disused sand and gravel open pit not far from the Aikhal village. This conifer is not native to this area and does not grow locally on its own.

Once all the work is complete, the land beneath the tailings pit will be restored to its original condition and, as mentioned, over 650 ha of replanted area will be handed over to local authorities.

UMS gearing up for shaft sinking work at Karowe Underground

With a team comprising some of the most experienced professionals in shaft sinking, United Mining Services (UMS) says it is gearing up for the pre-sinking of two shafts for the Karowe Underground Mine Expansion Project (UGP) in Botswana.

Following the completion of the feasibility study for the Karowe UGP, UMS was appointed by Lucara Botswana Pty Ltd and JDS Energy & Mining Inc in October 2019 to engineer and design the shaft sinking of the production shaft (8.5 m in diameter), and the ventilation shaft (6 m diameter), both reaching a depth of approximately 750 m below surface.

Fully commissioned in 2012, Karowe is an open-pit diamond mine with operations until 2026. The UGP will extend Karowe’s mine life to at least 2040. At the end of 2020, Karowe’s total probable reserve stood at 53.9 Mt containing 7.4 Mct including stockpiles.

According to Lucara, the Karowe mine remains one of the best producing mines of high quality plus-10.8 ct diamonds, having yielded five of the 10 largest diamonds in recorded history. It is also the only mine to have recovered three diamonds greater than 1,000 ct.

Dr Pieter Louw, Group Executive Project Services at UMS and UMS’ Project Manager, says the company’s wealth of knowledge and expertise in shaft sinking played a key role in securing the contract, and that the company is bringing in the heavyweights in the industry for the project.

Louw, himself, has a long history in underground mining and shaft sinking, having worked for major players in the mining and engineering sectors. He was involved in the De Beers Venetia Underground Project feasibility study, as well as a number of other feasibility projects for mines that are now in development or have already started production.

Louw explains that the two shafts at Karowe will be blind sunk using conventional drill and blast techniques. The production and ventilation shafts will both have equipment installed to pre-sink to a shaft depth of 100 m, if required, to accommodate the main sink shaft equipment. The pre-sink phase also allows the sinking process to commence as soon as possible while the main sink infrastructure is being fabricated and installed.

The new underground mine’s production shaft will have an A-frame type headgear, which will hoist 21-t payload skips, and will have a single drum auxiliary winder for people movement, and a man/material winder with counterweight and a big cage to service the underground.

UMS has refurbished four winders, which will be going to the mine for shaft sinking, including two stage winders and two Kibble winders. The company also purchased and refurbished Scotch derrick winder cranes for the pre-sink.

Louw says that UMS is in the process of mobilising up to 170 people to site for the pre-sink, which is expected to commence at the end of August and will take between eight and 12 months to achieve changeover ready for the start of the main sink. The main sink will take another two years after that, ready for mine development to commence in 2024, and full underground operations in 2026.

To make sinking safer, Louw says that UMS has adopted different sinking methodologies and equipment to be used at Karowe.

“In the past, we used to sink with cactus grabs which needed people in the bottom,” Louw said. “We are now using vertical shaft muckers and are buying state-of-the-art jumbo drill rigs to drill at the bottom. We’re doing inline work as opposed to concurrent work with people working at the bottom.”

He adds that, as part of its safety management plan, UMS has established a training centre on site at Karowe that facilitates inductions and training of local operators on the various equipment. The company is constructing a mock-up training tower on the surface to train operators on vertical shaft muckers and will have a similar training simulator for excavator operators.

Louw says UMS is fully established in Botswana and has partnered with Botswana Investment and Trade Centre to ensure that the project work permits run smoothly. Furthermore, the UMS design engineers are registered with the Botswana certification boards and can sign off all engineering designs and drawings for the project.

UMS to start pre-sinking work at Lucara’s Karowe Underground Expansion project

Lucara Diamond Corp’s Karowe Underground Expansion project (UGP) in Botswana is moving ahead with mobilisation of shaft sinking teams commencing late in June, and pre-sinking activities scheduled in the September quarter.

The Karowe UGP, which is expected to extend the operation’s mine life to 2040, is in a fully-financed position, with the latest schedule expected to see underground production hit full production by the end of 2026.

The 2019 feasibility study for the project envisaged life of mine production of 7.8 Mct, a payback period of 2.8 years and an after-tax NPV (5% discount) of $718 million; all from $514 million in pre-production capital.

COVID-19 delays have pushed the project off the original schedule – both in terms of timeline and cost – but the company says it is now making headway towards a 2026 start to underground production.

Lucara said no “material variances” between the 2019 feasibility study and the current execution plan have resulted, despite the delays.

“Rather, during this period in 2020 and 2021, all critical path items were addressed and a concerted effort was placed on detailed design, engineering and procurement which have helped to significantly de-risk the project,” it said.

Out of the total capital budget, the company has spent $51.4 million on project execution activities through 2020 until the end of June 2021, including shaft and geotechnical engineering, procurement of long lead time and essential shaft sinking items, surface infrastructure and construction activities, bulk power supply power line engineering and procurement.

Mobilisation of the shaft pre-sink team has commenced with shaft pre-sinking on track to commence in the middle of the current quarter.

Detailed engineering and design of the underground infrastructure and layouts will commence this quarter and are expected to be competed in the September quarter of 2022, with no major changes from the 2019 study plan anticipated.

Underground mine development is scheduled to commence in the second half of 2024 with underground production ramp up starting in 2026. Full production is scheduled for the end of 2026.

At the same time, open-pit mining operations have been adjusted to limit the risk of production shortfalls during the ramp up of the underground mine operations commencing in the first half of 2026. The open-pit mine is expected to terminate in mid-2026, Lucara said.

Access to the underground mine will be via two vertical shafts, the production and ventilation shafts. The shafts will be concrete lined with the production shaft acting as the main air intake and the ventilation shaft as the exhaust.

The number of shaft stations and nominal elevations remain the same as the feasibility study, with the planned depth of the production shaft still at around 767 m. The final planned depth of the ventilation shaft has, however, increased marginally to 733 m, from 716 m.

A 7,200 t/d shaft operation using long hole shrinkage (LHS) mining will provide an additional 13 years of mine life to the Karowe operation after a five-year construction period. The 767-m-deep production shaft will be equipped with two 21 t skips for production hoisting and a service cage for man and material movement through the mine. This shaft will also serve as the main fresh air intake to the mine.

The pre-sink construction contract and shaft sinking equipment procurement were awarded to UMS Botswana and UMS South Africa, respectively. METS International Ltd, a subsidiary of UMS, was awarded the shaft engineering contract.

The company explained: “Detailed design and engineering work on the production and ventilation shafts is now 90% complete, and has resulted in the following changes to the 2019 feasibility study: i) production shaft diameter has increased from 8 m to 8.5 m, ii) ventilation shaft permanent headframe, hoists and internal conveyances have been removed, iii) parallel pre-sinking of both shafts, iv) ventilation fans and coolers to be located on surface, v) in-shaft grouting of water strikes changed from grout curtain installation from surface, vi) planned development of an additional sublevel to assist in drilling of drawbells, and vii) removal of 670L de-watering galleries.”

Increased schedule time related to shaft sinking has been a result of the increased production shaft diameter, time allowances for in-shaft grouting during sinking operations planned at known water strike horizons, holing through all shaft stations between shafts and additional ground support for underground stations/level breakouts, the company said.

UMS is in the process of mobilising crews to Karowe to initiate pre-sink works. Pre-sinking of the two shafts will run in parallel and start with mobile cranes and then transition to Scott Derrick cranes with the final depth of pre-sink at around 40 m below surface.

With the exception of an additional sublevel (340L) to assist with drill and blast of drawbells, the design, layout and infrastructure of the underground mine all remain aligned with the 2019 feasibility study, the company noted.

Temporary power for shaft sinking is required until such time as the upgrade bulk power supply infrastructure is commissioned in the December quarter of 2022. A three-phased ramp up of the generator capacity is planned to support the increasing power requirements related to the shaft sinking activities.

A power supply and services contract for the temporary generators has been signed with Aggreko International Projects Ltd. Mobilisation has been initiated with the generator pad established. Commissioning of Phase 1 is scheduled during the September quarter to support the start of pre-sink activities.

The Karowe UGP is targeting the substantial resources remaining below the economic extents of the open pit in the South Lobe.

The LHS method is planned to systematically drill and blast the entire lobe on a vertical retreat basis. In LHS, a significant proportion of the blasted muck is left in the stope during blasting and stoping to stabilise the host rock with only the swell extracted during the drill and blast phase. Mucking will take place from draw points from the 310L extraction level. Once the column is fully blasted, the stope will be drawn empty by mucking the draw points.

The bottom-up approach of the LHS mining method takes advantage of the higher value EM/PK(S) kimberlite unit at depth in the South Lobe at Karowe, and balances high initial capital costs with low operating costs while de-risking the project with respect to the geotechnical and hydrogeological aspects of the host rocks, according to Lucara.

A revised project cost and schedule has been developed that captures the detailed engineering and design work through 2020 until May 2021, incorporating all changes, improvements, and COVID-19 related delays. Overall capital expenditures, including contingency, have increased marginally by some 4%, to $534 million, driven by the increase to the production shaft diameter and additional mine development.

The schedule to 75% of full production has increased by 1.3 years, driven mainly by COVID-19-related delays to commence the shaft pre-sinking and additional planned time for shaft station break-outs and ground support, Lucara added.

During 2020, Lucara negotiated and signed a self-build agreement with the Botswana Power Corp (BPC) for the construction of two substations and a 29-km-long 132 kV transmission line from BPC’s newly established Letlhakane substation to the Karowe mine. The planned route follows an existing regional 400 kV line and then runs parallel to the existing 11 kV transmission line currently supplying bulk power to the Karowe mine.

The new power infrastructure will provide the required power for the current open pit, processing plant and the underground mine expansion. Commissioning of and handover to BPC is scheduled for the December quarter of 2022. Construction of substations is scheduled to commence this quarter and power line construction in the March quarter of 2022, the company said.

JDS Energy & Mining Inc is the engineering procurement and construction manager for the execution of the Karowe UGP and is currently building up the on-site project team in conjunction with Lucara’s owners team and working in close cooperation with the Karowe Diamond Mine operations team.

ALROSA looks to ABEL HM pumps for filter press feeding

Piston diaphragm pumps from ABEL are helping Russia’s ALROSA with its filtration process at one of its diamond mines in the country.

In Spring 2021, ABEL received an order for the delivery of six of these piston diaphragm pumps, HM pumps, following an initial HM pump order in 2020. This inaugural pump was delivered to ALROSA in February 2020 as replacement for a centrifugal pump previously used for filter press feeding. At the beginning of August, the ABEL pump was commissioned at the diamond producer’s plant. The dewatering result (higher solids content, shorter filtration time) was so convincing that ALROSA decided to feed all filter presses in this plant with the pumps, ABEL said.

The latest delivery is being facilitated by ABEL’s official distributor in Russia, SibComplectService.

ABEL’s HM pumps are available as single- or double-acting versions. They come with a high flow rate, reliable function and particularly low operating and maintenance costs, the company says.

In addition to filter press feeding, the hydraulic diaphragm pumps are also used for sludge transport, spray dryer feeding, rotary kiln feeding, autoclave feeding, and sealing/rinsing water supply, among other applications.

TOMRA completes the diamond recovery loop with new XRT solution

TOMRA Sorting Mining says it is breaking new ground with a “unique” X-ray Transmission (XRT) Final Recovery solution that guarantees 99% diamond recovery.

With the new introduction, TOMRA is the first company in the industry able to supply a full diamond recovery solution using XRT technology from 2-100 mm, coupled with all the benefits of cloud computing for monitoring and managing the entire process, it said.

The new TOMRA COM XRT 300/FR final recovery sorter delivers concentration factors of up to one million with limited stages and is the only solution on the market that guarantees more than 99% diamond recovery, according to the company.

“The new sorter stands out for the high sorting efficiencies, the high diamond-by-weight concentrate, and the benefits deriving from its focus on a single consistent detection principal, diamonds,” the company said. “With this new introduction, TOMRA offers a complete partnered diamond recovery ecosystem with a flowsheet covering the entire process – from concentration to final recovery and sort house – and includes custom development with the end-user all the way to installation, then continued management of the asset and support with specialised services and training.”

The TOMRA COM XRT 300/FR is the latest step in TOMRA’s long-term diamond sector strategy, Geoffrey Madderson, Diamond Segment Manager for TOMRA Sorting Mining.

“We always had this clear objective, but the technology just didn’t exist,” he said. “We knew that to achieve our goal, we would need extremely advanced sensor technology. We have been working in-house on the development the new ultra-high resolution sensor more than five years, and now we are able to close the loop: the COM XRT 300/FR is the last piece within our recovery process, covering the final recovery and sort house applications to produce an ultra-high diamond-by-weight concentrate.”

TOMRA says its holistic approach and unique offering has earned a strong market trust in its XRT technology. As a result, the first three TOMRA COM XRT 300/FR sorters produced have already been sold to customers, all of whom purchased the machines on the back of their experience of previous TOMRA sorters.

The makeup of the TOMRA COM XRT 300/FR sorters sees input material evenly fed via a vibration feeder onto a conveyor belt. An electric X-ray tube creates a broad-band radiation, which penetrates the material and provides spectral absorption information. This is measured with an X-ray camera using DUOLINE® sensor technology, which focuses on a single, constant property of the material, density, it explained.

The advanced ultra-high resolution sensor information is processed and analysed by our TOMRA’s new Image Processing Pipeline to provide a detailed “density image” of the material, allowing it to be separated into high- and low-density fractions. If diamonds are detected, it commands the control unit to open the appropriate valves of the ejection module at the end of the conveyor belt. The detected diamonds are separated from the material flow by jets of compressed air. The sorted material is divided into two fractions in the separation chamber.

The tight tolerances and accurate alignment of the new ultra-high resolution sensor results in a high-quality picture that ensures a clear discrimination between diamonds and low-density materials down to 2 mm, according to TOMRA. The sorter features high-speed valves with a fine nozzle pitch, which significantly reduces non-diamond material in the concentrate. The result is ultra-high diamond-by-weight concentrate with a guaranteed recovery of more than 99%, the company claims.

It is possible to replace multiple sorting stages with a single TOMRA COM XRT 300/FR sorter all the way down to hand sorting, according to the company. In the final recovery application, the sorter targets the highest tonnage through the sorter that can be achieved with the highest recovery efficiency, which ranges from five tonnes to one tonne. As a result, the operation benefits from a smaller footprint and achieves much better grade.

It is also possible to replace hand sorting with a TOMRA COM XRT 300/FR. In a sort house application, it targets the highest diamond-by-weight concentrate possible, with about half the tonnage than final recovery, bringing multiple benefits. It removes the traditional bottlenecks around hand sorting efficiencies and eliminates the human error factor, the company says. In addition, it provides a high level of security by protecting the product from human intervention.

TOMRA’s partnered diamond recovery ecosystem includes consultation services during the development of the system and throughout the lifecycle of the equipment, support running the sorters, and help with specialised services and training. The company has also leveraged digital technologies to provide effective support, through its Virtual Demonstration and Test Solution and features such as the TOMRA Visual Assist Augmented Reality tool for remote assistance.

“With TOMRA, the customer’s entire recovery system falls into one ecosystem,” explains Madderson. “This allows for better compatibility and interconnectivity between the different applications of the recovery process. It gives our customers the full benefit of using cloud computing through our TOMRA Insight platform, which turns our sorters into connected machines. This enables customers to monitor and manage their recovery process in one easy-to-access place for both on-site and off-site management teams.”

TOMRA has set up a showroom dedicated to demonstrations of the TOMRA COM XRT 300/FR sorter at its Test Center in Wedel, Germany. Later in the year, TOMRA will also offer virtual demonstrations for those unable to travel to the Test Center.

Kwatani branching out from South Africa roots

Vibrating screen and feeder specialist Kwatani says it is transitioning from equipment supplier to solutions provider, as it attracts customers from well beyond its South Africa headquarters.

According to Kwatani General Manager Sales and Service, Jan Schoepflin, the company’s strong in-house expertise and design capability – combined with the manufacturing quality it consistently achieves – ensures its customised solutions deliver optimal performance at the lowest possible lifecycle costs.

“Our recent orders show that our customer base in Southern Africa remains strong, while there is growing recognition of our cost-effective offerings in West Africa, East Africa and North Africa,” says Schoepflin. “At the same time, orders from countries like Canada and Russia indicate that our markets abroad continue to grow.”

Kwatani says it remains the market leader in the supply and servicing of vibrating screens and feeders on iron ore and manganese mines in South Africa’s Northern Cape province. It also counts platinum, coal, diamond and gold mines in its customer base. Its West Africa orders have been mainly to gold mines, and there is growing potential for gold mining in East Africa, Schoepflin says.

Over its four decades of operation, Kwatani has produced about 16,000 custom-designed screens, and is building, on average, 30 to 40 units a month in its ISO 9001:2015 certified facility close to OR Tambo International Airport in Johannesburg.

“Our reputation has been built on prioritising what our customers need, and doing business with integrity and trust,” Schoepflin says. “This means delivering on what we promise and making sure that customers achieve the expected value from our products.”

The company’s solution focus is underpinned by its significant and ongoing investment in local skills, ensuring that its designs leverage strong mechanical and metallurgical engineering expertise, according to Schoepflin.

“This confidence in our products allows us to offer a process guarantee to customers, to deliver the tonnage, throughput and fractions that they expect,” he says. “Depending on which country our customers operate in, they may also have different industry and quality standards/certification expectations and we work closely with them to understand these clearly and meet their requirements.”

Schoepflin also emphasises the company’s service capabilities, which include its local service centres closer to customers, and its support partners in other countries.

“The careful selection of these partners is vital to meet customers’ stringent technical expectations,” Schoepflin says. “In some countries, our partners can also manufacture components according to our drawings and specifications, should there be an urgent requirement from a customer.”