Tag Archives: lead

HPY provides ‘transformational’ ore sorting upgrade at Fankou lead-zinc operation

HPY prides itself on being “the manufacturer of the world’s most diverse and efficient ore sorting product line” and, it says, this has been proven in the newest technical upgrades carried out on Shenzhen Zhongjin Lingnan Nonfemet’s Fankou Mineral Processing Plant and Construction Material Plant, in China.

Through the strategic use of all new models of HPY’s sensor-based sorting machines, Fankou’s Mineral Processing Plant has experienced a transformation in the sorting system, the company says. The mine can now sort coarse particle sized ores using HPY’s Golden Coal Series, elevating efficiency in the SAG mill, reducing the energy consumption of the whole system and significantly reducing the size of the mine’s tailings pond.

Previously, Fankou had registered a $2.9 million annual revenue increase following the introduction of four HPY Classic Series sorters. Currently, one Circle Series XRT sorter has the same sorting capacity as two conveyor belt-based sorting machines; the most recent technical upgrade allowed Fankou to replace four Classic Series sorters with two Circle Series sorters, reducing electricity usage by 14 times. These figures demonstrate the significant financial benefits that can be achieved using HPY technology, HPY says

In the article, “Maximising the benefits of sensor-based ore sorting machines,” published in April 2023, HPY Technology outlined how the cooperation project came together.

Fankou’s two process plants, the Mineral Processing Plant and the Construction Material Plant, are in Renhua County, Guangdong, China, and have a long history. Once one of Asia’s largest lead-zinc mines, this mine faced significant challenges as the years progressed. As Mr Luo, the plant’s General Manager, explains, “In its peak year, it could deliver approximately 180,000 tons of lead-zinc. However, after over 60 years of production, depleting resources and accumulating waste rock piles forced the mine to take drastic measures to modify the entire processing chain.” Such conditions underscored the necessity for solutions like HPY’s machines.

Fankou’s entire modification plan was ambitious; its total budget was estimated at $27.6 million since it needed to lay the groundwork and renovate the building, adding HPY’s ore sorting step to the process flow fitted nicely within its plan of upgrading its overall mining process.

At the end of 2017, Fankou’s executive team went to HPY Technology’s testing centre to carry out preliminary sorting tests. Mr Luo noted: “There were few companies in China that did sensor-based sorting at the time; in addition, Fankou’s lead-zinc was considered by many the ‘hard-to-sort’ type.”

Not long after, HPY and Fankou’s team decided to approach this project as a research project in 2018, the two parties agreed HPY would form a dedicated team to conduct specialised research on providing the most economical and technically responsible lead-zinc sorting solutions for the Fankou project. It did not take long for satisfactory results to start coming in. HPY successfully fulfilled its mission in 2019, and the machines were officially added to the plant thereafter.

Fankou’s mineral processing plant initially used four Classic Series P60-X1400 ore sorting machines. The machine processes the particle size range of +10-90 mm, which accounts for about 50% of the raw ore. This accounts for 2,600 tons of ore, rejecting 400-500 t/d of waste rock. After pre-concentration, the lead and zinc content in the waste rock is below 0.3%, and the sulphur and iron content is below 3.8%. Therefore, the ore sorting process enriches the ore grade by 1.08% for lead and zinc and 2% for sulphur and iron.

Figure 1: Four Classic Series P60-X1400 ore sorters in Fankou’s mineral processing plant

This sorter is the typical conveyor belt metal separator in China, and similar designs are seen elsewhere.

The project highlighted how HPY’s boosted machinery throughput had positively impacted the safety aspect of the mine’s mining practice; the mine can now mine more areas by vertical blasting, eliminating the risk of personnel working underground entirely, it says.

Mr Luo commends HPY’s updated ore sorting machine for completely changing the way Fankou mines: “Due to the depletion of mineral resources and the Chinese government’s increasing emphasis on the ESG aspect of the big mines, we did underground mining before discovering the option of HPY sensor-based sorting. However, not only is the production rate not ideal, but because the space in the underground channels is very narrow, we need personnel to attend to the errands, which makes the mining production very low and extremely unsafe.” He added: “After vertical crater retreat and large blasting, a large number of tailings and the unnecessarily high cost generated in the mills during the processing can be significantly reduced with an ore sorter; all we need to do is send in carts, have it shoveled onto the bin, and have it crushed, screened and cabled to the sorters.”

Since its installation, HPY Technology has upgraded its entire product line. With an enhanced sensor detection system and a remodelled module design that allows for easy maintenance, HPY’s machines’ processing capacity significantly improves compared with the older models. By March 2023, after using HPY’s machines for four years, Fankou – now a ‘royal customer’ – was open and excited for another round of machine upgrading to increase the amount of sorted material.

Upon HPY’s advice, the Fankou Mineral Processing Plant switched its four Classic Series to two Circle Series and one Golden Coal Series (See Figure 2). The Golden Coal Series was previously made to sort coal; after some updates and redesign by the HPY R&D team, it is now made specially for large particle-sized ore sorting. In Fankou’s case, +40 mm-90 mm sized ores will enter the Golden Coal Series for pre-concentration. As for the two Circle Series on the side, their expertise lies in their accuracy in sorting and large processing capacity that could replace two typical conveyor belt-based sorters with one machine. Their particle size ranges from +10-40 mm, considering those are the major distribution sizes produced during the initial screening process in Fankou. However, according to Mr Luo, Fankou is still in the process of optimisation now that the upgraded machines could process greater size distributions: “In the past, ores that are larger than 90 mm will enter straight into the SAG mill process, we plan to increase the Circle Series particle size to +10-60 mm and feed the +60-150 mm to the Golden Coal Series, this will help us increase the efficiency of the semi-autogenous mill process even more.”

Figure 2: Left being the Golden Coal Series, the middle and the side ring-shaped machine being the Circle Series

The ore sorting process modification consists of first removing one Classic Series and replacing it with a Golden Coal Series. The installation and training process took one month, and, by June 2023, the Golden Coal Series was running at total capacity. The two Circle Series’ implementation stretched longer as the mine could only halt its production for installation during more extended holidays in October 2023 and February 2024. Therefore, it took the entire Fankou Mineral Processing Plant a year to update all of the ore sorting machines (see Figure 3).

As mentioned before, the processing capacity prior to the update was around 2,500-2,600 t/d; after the machine update was completed, it went up to 3,500 t/d. A benefit of this update is that the Circle Series has less power consumption; thus, more revenue is generated from the sorted ore. The circular vibrating material layout maximises the symmetrical mass of the disc, requiring minimal excitation force to drive the ore toward the circumferential direction evenly. This significantly reduces energy consumption compared with traditional feeders, which rely on excitation force to move under their own weight, HPY says. Compared with belt-type ore sorting equipment with a width of 1.4 m, the energy consumption of this 1.5-m diameter disc feeder machine can be reduced from 7.5 kW to 0.75 kW.

HPY Technology | Fankou lead-zinc Mine, Mineral Processing Plant
Machine used One Golden Coal Series | Two Circle Series
Processing capacity 3,500 t/d
Particle size +10-150 mm
Concentrated ore grade (Pb+Zn) 12% (most economic ore grade)
Waste rock grade (Pb+Zn) <0.3%
Grinding grade (Pb+Zn) increased by 1.08%
Rejection rate 16-17%
Figure 3: Before and After with the HPY machine update in Fankou

The Chinese government has ordered Fankou to close its tailings pond by 2025. Thanks to the support of HPY Technology Golden Coal Series coarse particle sorters, Fankou is able to effectively decrease its tailings pond and have 58% leftover tailings for backfill, it says. In the close circuit of the Fankou Mineral Processing Plant, every resource is used and no ore has gone to waste.

“At HPY, we are focused on exploring paths that may revolutionise the mining of natural resources and pushing forward sustainable extraction through our expertise in resource management,” Coral Lin, Manager of HPY Branding Department, says.

DMC Mining to construct Clark exploration decline at South32 Hermosa

DMC Mining Services says it will construct the Clark exploration decline at the South32-owned Hermosa site in Arizona, USA, as part of a recent contract award.

In an announcement last month, South32 said the board had provided the final investment approval to develop the Taylor deposit, part of the wider Hermosa project, with funding of $2.16 billion. This followed the release of a feasibility study outlining a circa-4.3 Mt/y operation with average payable zinc-equivalent output of circa-253,000 t/y over a 28-year mine life.

Beyond Taylor, however, South32 has been working on its Clark development option, currently the only advanced project in the USA with a clear pathway to produce battery-grade manganese from locally sourced ore, according to the company.

In May 2023, South32 released the results of a selection phase pre-feasibility study (PFS-S) for the Clark deposit, which confirmed the potential for an underground mine integrated with Taylor, and a separate process plant, capable of supplying battery-grade manganese. Study work has progressed to a definition phase pre-feasibility study, with South32 confirming the commencement of construction of an exploration decline, due to be completed in late 2025, to enable access to ore for demonstration-scale production. This is where DMC Mining comes in.

In announcing this contract award, DMC Mining said: “Throughout the meticulous planning phase, South32 and DMC have been united by a shared vision and unwavering values, setting the stage for unparalleled success. Together, we’re not just setting the bar, we’re raising it, ready to redefine industry standards!

“This project not only underscores our commitment to delivering superior project solutions, but also signifies a significant stride in our dedication to serving our clients in the US market.”

TOMRA Mining talks sulphide ore sorting in copper, zinc, lead space

When processing sulphide ores to extract copper, zinc or lead, the focus is on ensuring that the mill is always operating at full capacity. The challenge is to optimise the process by eliminating waste in the early stages and maintain a high recovery rate, TOMRA Mining says.

This means that less barren or low-content rock will be processed, consequently increasing the metal content in the input of the mill. The result: significant cost savings and reduced environmental impact per produced tonne of metal.

In the case of copper, the mineralogy and lithology of the ore will affect how effective sorting can be at removing waste. When sorting copper sulphides with a non-disseminated texture, the focus is on waste removal to maximise recovery. However, three quarters of global copper production come from porphyry deposits, where very small grains of the metal are disseminated, making detection particularly challenging. Zinc and lead sulphides present similar sorting challenges to non-disseminated copper, although the metal content in the mineral is typically higher, so the focus will be on waste removal while maintaining the recovery levels.

The technology to sort copper, zinc and lead sulphides effectively to optimise the process is available from TOMRA Mining, it says. Its X-ray Transmission (XRT) sensor-based sorting technology can effectively detect sulphides in mineralised run of mine materials as they carry elements with higher atomic densities than non-mineralised waste rocks. After crushing, the ore in a size range from +8 mm to 80 mm is fed into the sorters and the barren and low content rocks are eliminated, resulting in a higher head grade of the mill feed. In addition, the eliminated waste can be replaced in the mill with more upgraded sulphides, increasing the efficiency of the mineral process.

However, in order to maintain the capacity of the mill, it is necessary to increase the amount fed to the crusher. This will have an impact on the mine and extraction planning. Due to the lower processing costs of sensor-based sorting, it is also possible to bring this in the calculation of the resource evaluation and the final pit design, according to TOMRA Mining.

TOMRA’s XRT sorters scan the individual rocks fed into the machine on a conveyor belt with overhead X-ray sources. At the same time, detectors located inside the belt collect data from the ore. The position of sensors, close to the rocks, combined with the strong X-ray power sources result in extra high-resolution images. This enables TOMRA’s XRT sorters to effectively process even most of the challenging porphyry copper disseminated deposits. Waste rocks are ejected by high-precision, fast pneumatic module, which adds to the sorter’s efficiency.

In copper sulphides with disseminated texture, a TOMRA XRT sorter can achieve an upgrade ratio of copper content in the mill feed ranging from 20% to 100%, while separating 20%-45% of mass as the waste material. With porphyry copper, the cut-off grade is typically 0.5%, but in view of the surging demand, it is now often as low as 0.2-0.3%. With TOMRA’s XRT technology, it is possible to achieve high recovery rates even at the lower grade, as shown by the tests conducted on run-of-mine samples from at OZ Minerals’ Antas Norte mine, in Brazil, the company says. The sorter demonstrated its ability to achieve recovery rates of at least 90% or reduce the waste grade down to 0.3% copper.

Heitor Mesquita Carmelo, Plant Manager at OZ Minerals Brazil, explains: “A bulk test was conducted to evaluate TOMRA’s XRT technology, and subsequently, the company decided to test it continuously in a pilot installation at the Antas Norte site. The results were consistent in both tests, demonstrating that the technology is effective for industrial application. TOMRA’s technology holds significant potential for OZ Minerals Brazil’s strategic plan, with the possibility of making deposits with lower ore grades viable, reducing operational costs, enhancing transportation safety for pre-concentrated ore, as well as decreasing the CO2 emission resulting from this activity.”

Heitor Mesquita Carmelo, Plant Manager at OZ Minerals Brazil

In lead and zinc sulphides, tests conducted by TOMRA have shown that it is possible to achieve an upgrade ratio of two to three times lead or zinc in the output of the sorter. Here the mineralisation plays an important role and can dramatically affect the upgrade ratio, TOMRA Mining says.

TOMRA’s XRT sorter delivers multiple benefits for copper, zinc and lead mining operations, beginning with its uniquely high capacity, which can be as high as 150-200 t/h per sorting width meter – a differentiator of TOMRA’s which also meets the requirements for medium- and large-size operations, it says. The sorter’s operational efficiency can be further improved with TOMRA Insight, a cloud-based subscription service that turns the sorter into a connected device that generates process data. It enables mining operations to monitor and measure performance in real time and optimise the process as well as tracking faults to improve maintenance and keep the plant always operating at its best.

Another important benefit of the sorter is the capacity to lower operating costs through its efficiency and energy saving features such as its ejection module that uses compressed air to eject the particles – up to 80% less compared to other ejection systems – dramatically reducing energy consumption compared to conventional sorting machines.

Optimising the process also reduces its impact on the environment. In addition, TOMRA’s XRT technology is a dry process, so that the overall use of water and chemicals is also reduced.

MMG-Roseberg-HxGN-OAS

MMG and Hexagon achieve ‘Australia first’ fatigue detection tech installation at Rosebery

MMG Rosebery says it has become the first mine in Australia to introduce fatigue detection technology in its underground operations, installing the HxGN MineProtect Operator Alertness System across the site in Tasmania.

The system, from Hexagon’s Mining division, has for the first time been installed in underground vehicles to detect fatigue and distraction in real time during 12-hour shifts, further strengthening the safety measures already in place to protect Rosebery’s 530 strong workforce.

Rosebery Mine General Manager, Steve Scott, said MMG continues to look at new and innovative ways to enhance safety across the mine site.

“Our number one value is we always think safety first, and nothing is more important than ensuring all our people go home safely at the end of each day,” he said.

“We recognise that with long shifts, fatigue can become a hazard and this technology enables us to continue to assess the fatigue risk of our underground truck operators in real time.”

The camera technology sits on the vehicle’s dashboard and will send alerts through audible sounds and seat vibration when it detects fatigue and distraction.

Rosebery Mine worked with Hexagon to install the technology in 11 underground trucks with 81 operators now registered to use the system.

Scott said the feedback from MMG’s people using the system has been overwhelmingly positive.

“They’ve seen real value in the technology because it not only helps them to recognise that they’re tired, but also manage their fatigue better after their shifts,” he said. “We have a culture at Rosebery where we encourage a positive and safe workplace, and this is just another initiative that helps us achieve that.”

The Rosebery Mine is one of Tasmania’s largest and oldest continuously operating, underground mines producing zinc, copper and lead concentrates, as well as gold doré.

Pictured is Chantelle Moretti, an Underground Truck Operator at Rosebery, holding the card to log onto the HxGN OAS.

Leveraging electric heat-trace cables to prevent freezing pipes and pipelines

Feeding water into a mine, the dewatering of groundwater out of it, and the recycling of used water all depend upon a network of reliable piping systems able to withstand mining’s extreme environments, whether the mine is underground or on the surface.

In remote areas such as Alaska or northwest Canada, pipes carrying water, slurry, tailings, chemicals or other liquids can be subjected to dangerously cold temperatures. Unprotected pipes can easily freeze in this cold, expand and then burst, no matter how strong the material they’re made of. A freeze can also result in ice blockages in pipes that cripple production, according to Matthew Gurreri and Kevin Green* write.

One burst or blocked pipe can bring an entire mining operation to a halt, resulting in punishing financial losses. In addition, lives can be put in jeopardy by the depressurising of fire suppression systems, for instance, or by the flooding of tunnels. Another issue is the environment. Leaks of contaminated water containing heavy metals like copper, lead and arsenic may spill into nearby waterways creating an ecological disaster. The high cost of downtime stemming from a frozen or blocked pipe can be exacerbated by a lack of on-site replacement parts. Icy roads are often impassable in winter, leaving delivery of replacement parts limited to cargo planes or sea lifts. Logistics can become extremely complicated, as well as expensive, in remote arctic locations.

Besides water, most air-filled lines operating inside or outside a mine can freeze, even at temperatures as warm as 40° F. As air pressure drops from 100 psi down to atmosphere, the compressed air, which is always at 100% humidity, super cools rapidly and can freeze up lines and seriously damage mining equipment.

The importance of preventing water pipes and air-filled lines from freezing cannot be overstated. Water is involved at every stage in production: mining, downstream processing and product conveyance. Large quantities of water are also used for cooling the cutting edges of machinery, heap leaching, dust suppression, general cleaning, fire sprinklers and fresh drinking water. Air-filled lines are needed to supply critical power to pneumatic tools and mining equipment.

Protecting pipes

Pipes installed in mining operations are made of materials appropriate to the duty required. Steel pipes are the industry standard. However, lightweight, corrosion-resistant and lower cost plastic pipes, such as HDPE and PE, are increasingly being deployed. Pipes are hung by chains from brackets typically attached to roof bolts.

Along with the threats posed by harsh weather conditions, pipes installed in mines must withstand high external loads and surges in pressure, exposure to corrosive chemicals and abrasive slurries, steam purging, caustic acids and accidental damage by moving equipment – all of which can weaken the pipe structure and make it more susceptible to bursting in a freeze. Hairline cracks could develop, causing leakage, and eventually break.

Explosion risks

Statistics from the Mine Safety and Health Administration (MSHA) indicate that mine explosions occur most often during colder months because of low barometric pressure and low humidity. In cold weather, coal dust can be dangerously suspended in dry cold atmospheres, increasing the hazard of explosion. Low barometric pressures help methane spread easily into active areas, further heightening the risk of explosion. All it takes is a spark from an electrical device, including the switching “on” and “off” of a non-rated heat-trace cable, to ignite a disaster in a classified area containing explosive dust or gases. A lower-quality, malfunctioning heat trace cable can also generate enough heat to set off an explosion in a hazardous location.

Heating cables must be certified for the hazardous location where they are installed. Period. It is extremely dangerous to trust the future of a mine and the lives of its employees to offshore heating cables that may or may not be engineered to the certifications they claim to carry.

Long-distance applications

Mining requires long pipelines and consequently, equally long heat-tracing applications both for freeze protection or for viscosity control and temperature maintenance. Measuring from a few hundred yards to several miles, long distance systems are typically custom engineered. Many variables must be taken into consideration to achieve the most reliable solution for the targeted distance, including factors like self-regulating or constant wattage, supply voltage, minimum temperature at start-up, circuit breaker amperage, pipe diameter, and wire gauge, among many others. In determining heating cable length, the pipe length must be added to the junction box entry and end seal, the number of flanges, and the size and number of valves.

Fire suppression in mines

Ice blockage hinders the suppression abilities of a fire sprinkler system and can break pipes altogether. Frozen sprinkler pipes are dangerous in a commercial building, of course, but can amount to even a greater risk in a mine. In the event of an underground mine fire, it is critical to extinguish the fire in its early stages. Any delay in initiating firefighting activities can result in an uncontrolled fire. Unfortunately, just as sprinkler pipes can freeze, so can the mine’s underground fire hydrants, fire water hoses and surface water storage tanks. All need freeze protection.

Often a sprinkler pipe doesn’t freeze completely. Instead, the water will freeze, thaw and freeze again when exposed to low temperatures. This phenomenon applies added stress to the pipe. Even if a pipe thaws out after a freezing event and appears stable, its integrity is compromised. Hairline cracks can be subtle and difficult to locate until too late.

A frozen pipe in a mine can be dangerous, even deadly.

For instance, in December 2004, a heavy equipment operator in a Kentucky mine was fatally injured while he was trying to dislodge frozen slurry from a slurry pipeline that had iced over.

In 2012 at an oil sands project, about 60 km south of Fort McMurray, Alberta, Canada, a worker was in the process of steaming a frozen pipe when a section of the pipe ruptured, striking the worker in the leg. The 62-year-old worker was transported to a hospital in nearby Lac La Biche where he passed away.

More commonthan these issues is frozen water in pipes that lead to crippling issues ranging from improper functioning of equipment and premature parts failure all the way to more costly damage caused by freeze-and-thaw issues or thermal shock.

Electric heat-trace cables will prevent water, compressed air, slurry and other liquids from freezing in pipes and lines, protecting your property, people and profits.

*Matthew Gurreri is Product Marketing Manager, Emerson Automation Systems, and Kevin Green is National Sales Manager, Emerson Automation Systems

Appian Capital to take on Rosh Pinah zinc-lead mine in Namibia

Appian Capital Advisory LLP, the investment advisor to long-term value-focused private capital funds that invest in mining and mining-related companies, has acquired an 89.96% interest in the producing Rosh Pinah zinc mine, in the Kharas region in southern Namibia, from Trevali Mining Corporation.

Rosh Pinah is an operating underground zinc-lead mine with a 2,000 t/d milling operation, which has plans in place – via the Rosh Pinah 2.0 mine expansion project – to nearly double the mine’s annual ore throughput to 1.3 Mt and improve safety and environmental performance. The mine has been in continuous operation since 1969, producing zinc and lead sulphide concentrates, as well as smaller amounts of copper, silver and gold.

Appian says it will retain the existing site management team and workforce, who have substantive technical expertise and understanding of the asset.

Michael W Scherb, founder and CEO of Appian, said: “This acquisition marks a significant milestone for Appian as we continue to develop our world-class portfolio of highly attractive zinc assets, a critical metal that will help facilitate the upcoming energy transition. We look forward to welcoming the 450 employees at Rosh Pinah to Appian as we utilise our extensive operational and project development expertise to support the existing management team with delivering the Rosh Pinah 2.0 expansion project. We extend our gratitude to the Namibian government, our valued partners, and the local community for their trust and support.”

The Rosh Pinah 2.0 expansion project envisages the construction of new processing facilities, including the addition of a paste fill and water treatment plant, as well as a dedicated portal and decline to extended deposits. The project will increase mill throughput from 700,000 t/y to 1.3 Mt/y, increasing zinc equivalent production to 170 MIb/y (31,751 t/y), on average.

Trevali, the former 89.96% owner of Rosh Pinah, said previously that the expansion could also lead to the introduction of battery-electric vehicles at the mine.

Rosh Pinah is one of three recent investments by Appian in the zinc market, with the other two being Vedra Metals in Italy and Pine Point in Canada. It did not disclose the acquisition price for the stake in Rosh Pinah.

South32 and Redpath kick off shaft sinking works at Hermosa

South32 has now broken ground on one of two exploration shafts at the Hermosa project in southern Arizona, USA, in a sign of major progress at the base and battery metal project.

This milestone achievement commemorates the initial surface excavation that will be continued by Redpath USA to a planned depth of 900 m, the contractor stated in a LinkedIn post. Redpath and South32 signed a “limited notice to proceed” for shaft engineering and design at Hermosa last year.

Redpath said in this latest post: “The shafts will enable underground access for continued exploration of a world-class deposit containing the US critical mineral zinc as well as lead and silver – minerals needed for supporting electrification and renewable energy.”

In South32’s March quarter results, the company said it invested $176 million over the last nine months as it continued critical path activity and study work for the Taylor zinc-lead-silver deposit and the Clark battery-grade manganese-zinc-silver deposit. It also directed $12 million to capitalised exploration in the nine months ended March 2023 as it continued exploration programs at Taylor and Clark and the copper-lead-zinc-silver Peake prospect 8.

Just last month, the Hermosa project was confirmed by the United States Federal Permitting Improvement Steering Council, an independent federal agency, as the first mining project added to the FAST-41 process, which is focused on supporting informed decision-making while reducing and eliminating unnecessary and costly delays associated with projects.

Solar farm goes live at MMG’s Dugald River zinc-lead mine

MMG says the new solar farm at its Dugald River operations in Australia has hit the commerical operation milestone, two months after construction was completed.

Reporting in its March quarter results, the company said it expected the solar project to reduce the mine’s carbon footprint and provide immediate energy cost savings, with approximately one-third of gas-fired power used in Dugald River operations expected to be replaced.

Back in late-2021, MMG signed an agreement with APA Group to construct 44 MW of capacity to serve the Dugald River zinc-lead mine in Queensland, with operations expected in the March quarter of 2023.

Dugald River resumed production on March 21 after a suspension of 34 days due to a fatal incident at the mine involving two contractors from Barminco. MMG says the mine continues to ramp-up through April with the focus remaining on safely returning its workforce to the underground environment. Production in 2023 is now expected to be in the range of 135,000 t and 150,000 t of zinc in zinc concentrate, lower than the prior guidance of 170,000 t and 185,000 t.

Maximising the benefits of sensor-based ore sorting machines

Ore sorting has been shown to provide both economic and environmental benefits, but many mines are not yet fully utilising this technology, according to HPY Technology.

Yet, the company’s ore sorting machines are providing a breakthrough solution for Fankou, one of Asia’s largest lead and zinc mines, resulting in an annual revenue increase of around $9.22 million.

Located in Renhua County, Shaoguan City, Guangdong Province, Fankou is owned by Shenzhen Zhongjin Lingnan Nonfemet Co Ltd. The mine has been producing lead and zinc for over 60 years. However, with new underground mining processes, such as vertical crater retreat and large blasting, more waste rock is being introduced into the crushing, grinding and flotation processes, resulting in higher production costs and energy consumption.

Furthermore, under the “zero waste” target set by the Environmental Protection Law of China, Fankou’s tailings pond needs to be closed by 2025. As of 2018, the mine’s annual processing capacity was 1.5 Mt, with 600,000 t ending up in the tailings pond. In addition, Fankou’s waste rock piles had reached approximately 2 Mt. With the continuous addition of around 200,000 t/y of waste rock, these piles grew larger. With the pressure to meet the zero waste target, Fankou was under pressure to make a change.

In 2017, Fankou conducted exploratory tests of sensor-based ore sorting machines with Ganzhou HPY Technology Co Ltd. The result of the initial tests showed promise and addressed the problems the mine was beginning to face, according to HPY Technology. As a result, Fankou decided to add HPY Technology’s ore sorting machines to the industrial design plan of their mineral processing plant in 2018, and HPY Technology’s machines were officially added to the plant in 2019.

The Fankou lead-zinc mine currently produces about 1.4 Mt/y of ore, and it is expected that more than 105,000 t of waste rock will be pre-rejected from the raw ore throughout the year. Ore sorting technology can discard a large amount of waste rock from the raw ore before it is fed into the flotation system, reducing the amount of waste rock entering the mill and saving on electricity costs.

Fankou’s mineral processing plant uses four Classic Series P60-X1400 ore sorting machines. The machine processes the particle size range of +12-90 mm, which accounts for about 50% of the raw ore. This accounts for 2,600 t of ore, rejecting 400-500 t/d of waste rock. After pre-concentration, the lead and zinc content in the waste rock are below 0.3%, and the sulphur and iron content is below 3.8%. Therefore, the ore sorting process enriches the ore grade by 1.08% for lead and zinc and 2% for sulphur and iron.

Four Classic Series P60-X1400 ore sorters in Fankou’s mineral processing plant

After sorting the waste rock from the raw ore, this waste rock can be sold as construction aggregate to bring further economic benefits to the Fankou mine. This has also seen the amount of tailings decrease and the service life of the tailings pond extend significantly, resulting in remarkable energy savings and consumption performance, while also enhancing the mine’s societal value, HPY Technology says.

Mr Wang, Project Manager of Fankou Mineral Processing Plant, said: “We are proud to be one of the world’s first lead and zinc mines to utilise ore sorting fully. We see significant economic benefits for using HPY Technology’s ore sorting machine, especially for low-grade mines. China has huge lead and zinc ore reserves, the second largest in the world. But the grade of the deposits is generally low, with many poor and few rich ores. The average grade is about 1.5% for lead and 2.5% for zinc. Reserves with a grade below 5% account for more than 90% of lead ore, and reserves below 8% account for more than 85% of zinc ore. We hope to continue contributing to the mining industry’s progress and are willing to recommend HPY Technology’s ore sorting machine to our peers.”

The Classic Series used in Fankou’s mineral processing plant is a benchmark in the ore sorting industry, according to HPY Technology. This machine uses dual-energy X-ray technology, combined with high-speed air jets to sort ore from waste rock. The X-ray technology penetrates the ore and creates a grayscale image that distinguishes between target and vein minerals. This image is then processed by an artificial intelligence algorithm, which uses the information to accurately sort the ore and waste rock. The Classic Series has undergone numerous iterations, ensuring stable and efficient operation, HPY Technology says. It is currently the most widely used ore sorting machine in China’s mining industry, according to the company.

Fankou Lead-Zinc mine, mineral processing plant

HPY Technology | Fankou lead-zinc mine, mineral processing plant

Machine used Four Classic Series P60-X1400
Processing capacity 2,600 t/d
Particle size +12-90 mm
Concentrated ore grade (Pb+Zn) 12%
Waste rock grade (Pb+Zn) <0.3%
Grinding grade (Pb+Zn) increased by 1.08%
Rejection rate 16-17%

Fankou’s mineral processing plant can save more than $2.9 million/y by using HPY Technology’s ore sorting machines, resulting in an annual profit margin of more than $7.8 million, considering the comprehensive benefits of increased plant capacity, tailings reduction and construction aggregate sales.

In addition to the four Classic Series P60-X1400 in the mineral processing plant, the Construction Materials Plant has three HPY Technology ore sorting machines to process the waste rock from the mineral processing plant and its existing waste rock piles. The waste rock is taken to the construction material plant for another round of sorting, with the remaining waste rock being used for construction aggregates. The three machines at the construction materials plant also process the 2 million cu.m of waste rock initially stockpiled in the tailings pond.

Mr Luo, Project Manager of Solid Waste Treatment, said: “In the past, we could only transport solid waste back to the shaft for filling. After using HPY’s ore sorting machines, we can now sort out all the ore from solid waste and recover the value of the resources. The remaining waste rock can be sold as construction aggregates, which is a win-win solution. Currently, we are also sorting waste rock that was stored before using HPY’s ore sorting machines. The ore grade is about 3%. Sensor-based sorting technology enriches the ore grade to 12-14%. Sorting results show that the rejection rate exceeds 95%. In the global mining industry, Fankou is one the first to successfully apply intelligent ore sorting technology in lead and zinc mines, achieving maximum resource value recovery and is great for the environment.”

According to Mr Luo, waste rock that was initially made into construction aggregates now yields more than 1,500 t/y of lead and zinc metal, which has been able to be recovered through the Construction Materials Plant. In addition, the ore sorting process reduces the waste rock’s sulphur content. This substantially improves the grade of the construction aggregates, increasing its sales price. As a result, the waste rock made into construction aggregates generates about $977,000/y in economic benefits. In addition, the recovered ore generates over $2.8 million/y in benefits.

Fankou has utilised sensor-based ore sorting to its full extent, HPY Technology says, using it during the comminution process to pre-reject waste rock to increase its lead-zinc ore grade. The company also sees benefits from pre-rejected waste rock in reduced costs in its grinding process. With pressure to control the amount of tailings, the pre-rejected waste rock lowers the amount of tailings entering the tailings pond to help the company in its aim of closing the tailings pond in 2025. In addition, sensor-based ore sorting has allowed the company to gain additional revenue through the recovery of lead-zinc from their waste rock piles, while also utilising these piles for construction aggregates. Overall, the introduction of ore sorting has allowed the company to expand its resource recovery. By pre-rejecting and enriching low ore grades, Fankou can now mine areas previously deemed un-mineable due to having low grade ore, allowing them to increase the processing capacity each year.

Fankou lead-zinc mine, Construction Materials Plant

HPY Technology | Fankou lead-zinc mine, Construction Materials Plant

Machine used One Insight Series | Two Classic Series
Concentrated ore grade 12-14%
Waste rock grade Pb 0.04%, Zn 0.10%
Concentrate recovery rate Pb 96.76%, Zn 92.8%
Rejection rate 95%
Enrichment ratio Pb 9.68, Zn 9.28
Particle size +10-50 mm

The Insight Series used in Fankou’s Construction Materials Plant adopts a combined detection method comprised of a VIS HD dual-sided imaging system and X-ray technology, which can be customised according to the physical characteristics of different ores. The machine can collect the ore’s internal and external information simultaneously and with an AI algorithm, which can significantly improve the accuracy of ore sorting and better for sorting complex ores.

Compared with traditional ore sorting machines, which use a belt, the upgraded Insight Series utilises a vibrating feeder and short belt that leads to ore free fall, HPY Technology says. With the optimised mechanical design, the ore falls more evenly, avoiding ore overlap that affects recognition accuracy. In addition, the machine has various feeding widths (1,600 mm, 3,200 mm), which leads to processing capacities of 40-150 t/h (+10 mm-80 mm) to meet the needs of different mines needs during the beneficiation process.

As one of Asia’s largest lead and zinc mines, Fankou has taken steps to maximise the economic value of its process. Through the utilisation of sensor-based ore sorting, the company has seen significant increases in revenue and savings. Having worked with HPY Technology for over five years, Fankou looks to continue this partnership to further the research on the benefits of ore sorting machines. As HPY Technology continues innovating and revolutionising mineral processing, the benefits will only continue to grow, it says.

HPY Technology Co Ltd says it is a leader in the development and manufacture of ore sorting machinery, achieving excellent results in the ore sorting of tungsten, tin, antimony, lead, zinc, copper, molybdenum, gold, phosphate and over 30 other ore types, revolutionising the traditional mineral processing process and significantly promoting the technological progress of the global mining industry. With over 400 machines in use in over 100 mines, the company says it looks to continue revolutionising mineral processing.

South32 and Emesent collaborate on LiDAR-equipped Spot trials at Cannington

South32’s Cannington Mine, in Queensland, Australia, says it is supporting Emesent in its pursuit of developing and testing light detection and ranging (LiDAR) scanning and automation technologies in real underground mining environments.

The team from Emesent were recently on site at Cannington with Spot the Robot Dog, trialling Spot’s autonomy development and capabilities in the underground silver-lead mine.

While the technology is still in its research and development phase, it has the potential to guarantee safer outcomes and ultimately transform the way Cannington operates, South32 says. Mining work safety and productivity can be improved by deploying the autonomous capabilities of Spot in various potential scenarios with different data capturing tools, including scanning, video recording and heat sensing, it added.

The focus on site was testing Spot’s capability in ‘post blast re-entry’ scenarios and emergency response. Spot, with an integrated LiDAR scanner, autonomously navigated sections of the mine, travelling through uneven and wet ground without operator intervention and exploring unlit areas. It was able to produce a 3D Point Cloud map of the underground mine in the process, South32 said.

The Cannington team has previously worked with Emesent to help develop industry-leading technologies including its Hovermap System for underground scanning, which is now used in mines all over the world.