Tag Archives: TOMRA Test Center

TOMRA’s latest XRT advances open up processing options for miners

When it comes to particle sorting, size is everything. Whether used as a primary sorting method in smaller operations where product purity is paramount to profits, or in a scavenger setup downstream to capture value once lost to tailings, particle sorters are becoming more and more commonplace across the mining world.

They have featured in flowsheets in the industrial minerals space for decades, but they are now finding their way into metal operations all over the world as miners look to boost recoveries, reduce their energy consumption and, in many instances, rationalise their water use.

This makes TOMRA Mining’s latest advances in sensor-based ore sorting all the more significant.

The company is now breaking ground with a new ejection module for its COM Tertiary XRT (X-ray Transmission) sensor-based sorter specifically developed for sorting small particle sizes.

The COM Tertiary XRT Fines sorter, featuring the new TS100C module and the recently introduced image processing unit, is capable of sorting particle sizes down to 4 mm in high-capacity applications with much higher energy efficiency, delivering a high-quality product at low operating costs, according to the company.

The COM Tertiary XRT Fines sorter featuring the new TS100C ejection module has been installed at the TOMRA Test Center in Wedel, Germany

The high resolution TS100C ejection module features a new type of ejector that is four times faster than previous iterations, according to the company. Together with the new image processing unit, it delivers higher precision in sorting small particle sizes at high throughputs.

The mechanical design of the sorter has also been improved by the introduction of a new splitter plate and more precise calibration equipment to ensure the greater precision in the alignment between detection and ejection systems required for fine particles, according to TOMRA.

This has been captured in field tests that started back in May 2022, showing an up to 30 t/h boost in capacity, an increase in product recovery and a reduction in energy consumption.

Ines Hartwig, Director Product Management at TOMRA Mining, told IM on the side lines of the recent SME MINEXCHANGE 2023 Annual Conference & Expo in Denver, that the company had been able to visualise such small size particles previously, but the mechanical ejection function had not been able to keep up.

“This new ejection module is a significant leap forward for TOMRA, and we believe the whole particle sorting setup within the industry,” she said.

And, while the industrial minerals sector was the first one pushing for these developments, Hartwig said she expected the metal miners to also benefit from this.

“We have visited operations all over the world that have stockpiled fine material as they simply couldn’t process it with the technology on the market,” she said. “We’re now opening up many new opportunities for these companies.”

To gain field experience on the new ejection module, TOMRA partnered with a customer who has been running a COM Tertiary XRT to produce high-grade magnesite for more than two years. The sorter removes up to 50% low-grade and waste material from the raw magnesite feed, with particle sizes ranging from 10 to 35 mm at about 20 t/h.

Ines Hartwig, Director Product Management at TOMRA Mining

“After conducting the test work with the TS100C ejection module at the TOMRA Test Center, we were confident that it would be very beneficial for this customer,” Hartwig says. “We showed them the test results and outlined the benefits we expected the module to deliver. As soon as they saw the possible reduction in compressed air use and the consequent cost savings, they were very interested in doing the field trial!”

The customer, the magnesite operation in Turkey, completed several trials, documenting the energy savings and sorting efficiencies. The results showed a 70% reduction in air consumption with an increase in product recovery with a lower mass pull to waste by producing the same product quality, and a capacity increase ranging from 20 t/h to 30 t/h with comparable results, according to TOMRA.

The COM Tertiary XRT Fines sorter featuring the new TS100C ejection module has been installed at the TOMRA Test Center in Wedel, Germany, and is ready to run tests for customers on material samples from their mines, TOMRA says.

Hartwig said she expected existing COM Tertiary XRT customers to upgrade to the new module with the company’s retrofit solution, but there were also many new customers expected to acquire brand-new units.

“There is a significant ‘new’ market out there that we expect to take advantage of this technology,” she said. “The economic and environmental value case at many of these operations can be vastly improved by using the COM Tertiary XRT Fines sorter.”

TOMRA Mining’s ore sorting solution helps Renison tin mine do ‘more with less’

TOMRA Mining and its X-ray Transmission (XRT) technology has, the company says, provided an effective solution for the extreme conditions at the Bluestone Mines Tasmania JV (BMTJV) Renison tin mine in Tasmania, Australia, with sensor-based ore sorting solution unlocking significant value and delivering environmental benefits.

The Renison mine is 50% owned by Metals X through the BMTJV, and is the only major tin mine in production in Australia with a mining rate of close to 1 Mt/y, according to TOMRA. While slated capacity is 1 Mt/y, the concentrator is restricted to 750,000 t/y.

The mine’s extreme humidity and highly acidic processing water (pH around 4.5) create unique challenges for the sorting process, the equipment and waste management, according to TOMRA.

A complex flowsheet

The underground mine operates a primary crushing system before the material is transported to the surface through a shaft. Once there, it enters the pre-concentration plant, where it undergoes a three-stage crushing, screening and cleaning process. The particles are split into two fractions – 10-25 mm and 25-60 mm – which are fed into two TOMRA XRT sorters. The output consists of two streams: the product, which is transferred to the wet plant, and the waste, which is fed into a TOMRA EM sorter to separate acid-forming sulphides from this waste stream.

In the wet plant, the product goes through primary grinding followed by bulk sulphide flotation. The tailings are processed downstream to concentrate the cassiterite tin mineral through gravity concentration; gravity tails are further treated via desliming and tin flotation. The combined concentrates are fed to a leaching circuit to remove carbonate minerals. After a final wash stage, the concentrate is de-watered and dispatched.

BMTJV approached TOMRA to address two key requirements at the plant. The first was the need to upgrade the tin feed to the plant, as Ben Wraith, Principal Project Metallurgist at BMTJV (pictured below), explained: “The Renison tin operation wanted to achieve economies of scale, putting more tonnes through the front end of the plant without upgrading the back end downstream – we wanted to do more with less.”

The second requirement was to address the environmental issue of removing acid-forming sulphides from the waste.

Following site visits and extensive discussions with BMTJV’s teams, TOMRA proposed a solution that addressed the tin feed quality with two COM Tertiary XRT 1200 sorters and the waste issue with a COM Tertiary EM 1200 sorter. A team from BMTJV visited the TOMRA Test Center in Sydney, Australia, where they observed what the XRT sorter operating at capacity is capable of.

Gavin Rech, Technical Manager at TOMRA, said: “Our XRT stands out for the high spatial and density resolution and its ability to do contrast sorting, identifying fine high-density tin inclusions in the ore with an accuracy that has no equal on the market. On top of that, it can separate it from the acid-forming sulphides, so that we have the ability of pulling the tin into the first product and sending the rest to the EM sorter.”

Gavin Rech, Technical Manager at TOMRA

The two COM Tertiary XRT 1200 sorters went into operation in 2018. Initially, BMTJV’s strategy focused on low reject grades, devoting less focus to achieving the mass reject rate and overall process plant throughput. However, the specific conditions at the Renison mine affected the results achieved. The large variance in run of mine (ROM) particle size distribution resulted in insufficient stability in the feed to the circuit. In addition, the extremely wet conditions in west Tasmania and consequent high ambient moisture content, combined with the high moisture of the ore delivered from underground, further affected the sorting process.

In 2019, a new investigation was conducted into the ore sorting performance and led to a change of direction, where the operation shifted away from targeting low reject grades, towards sorting as aggressively as possible, according to Wraith, moving from a “tin recovery-based” operating strategy to a “mass reduction” one.

“We are getting 20-25% mass reduction, so 75-80% of the materials are going into the wet plant, and we are still achieving 97-98% tin recovery overall across the crushing circuit,” he said. “Pre-concentration didn’t materially impact overall recovery because the tin in the material that is rejected as waste is extremely fine grained and a proportion is associated with sulphides, so it wouldn’t have been fully recovered in the downstream wet plant and would have been lost to tailings.”

This approach, he said, is best for Bluestone’s application as it provides the ability to process 15-20% more tin units without having to upgrade the downstream concentrator.

Wraith added: “Operating the sorting circuit has slightly increased our overall processing cost, but this is more than offset by the large increase in ROM throughput by 15-20% and, thus, tin production, so the unit cost per tonne of tin produced is reduced by almost 10%. We’ve broken multiple production records in the last year in tin units, and this gives us confidence in what we can achieve because the machine performs over and over again if you treat it right and if you prepare your feed correctly.”

TOMRA XRT success leads to upgrade decision

In view of the results achieved with the two TOMRA XRT sorters, BMTJV decided to upgrade the ore sorting circuit with two new, recently launched XRT models with stainless steel internal parts and advanced features such as the TOMRA ACT user interface and the TOMRA Insight cloud-based platform, according to TOMRA.

“The decision to buy new machines was easy,” Wraith said. “The stainless steel will assist prolonging the TOMRA sorter’s life by protecting the unit from our high-moisture and corrosive environment. The more ergonomic design will help our maintenance teams, which is particularly important for machinery operating in these harsh conditions.”

Wraith said the use of TOMRA Insight, the ore sorting company’s subscription-based service that relays and analyses machine data, will “enhance everybody’s understanding and experience of the machines”.

He added: “It will be more of an analytical platform for our metallurgy and maintenance staff, providing ample opportunity to gain valuable information that can be analysed and optimised over time. The one feature I am personally interested in is the particle size monitoring through the machines, which will enhance our overall circuit performance because we have an integrated circuit with the crushing and screening plant. Feed preparation is key to maintain a consistent performance – knowing how well you’re preparing your feed in a live fashion can only end up with a better result.”

TOMRA will also be able to log into the machine and check the daily reports generated by TOMRA Insight, so its technical teams will be prepared ahead of site visits for maintenance or optimisation.

Wraith concluded: “TOMRA has been working with the site maintenance team to tailor solutions to our operating environment, which has been invaluable. TOMRA supported me through site visits, which included equipment inspections, site-based training of our personnel, and an openness to continually improving the technology and finetune it to our site-specific requirements. They assisted the site with troubleshooting, optimisation, discussing the nuts and bolts of the issues as they arose, and finding a solution that works.”