Tag Archives: mineral processing

AspenTech Mtell Agents getting ahead of the mine maintenance game

AspenTech is looking to turn condition monitoring procedures in the minerals processing plant on their head by providing prescriptive maintenance tools powered by machine learning that offer the earliest possible issue detection along with the required context to allow operators to act.

“After more than a decade of working on Mtell, we understand how to slot into an operation to make sure our data is clear, prescriptive and acted on,” Mike Brooks, Global Director of APM Solutions at AspenTech told IM recently.

Aspen Mtell® has been a gamechanger for industries such as metals and mining, according to the company, performing prescriptive maintenance by forecasting degradation and equipment failures, alerting staff in advance of when a failure could occur, identifying potential causes and the scope of any failure, and providing advice on the corrective action to avoid or mitigate the impending failure.

This is leading to increased operational efficiency, resulting in improved energy efficiency and reduced emissions, according to the company.

Unlike other mining-related predictive maintenance proponents, AspenTech and Aspen Mtell have been using machine learning for over a decade, using the benefits of this technology to improve on the condition monitoring and firefighting maintenance procedures in place at industrial sites.

“By obtaining sufficient domain knowledge and packaging it into a solution, we have created a product that is able to detect patterns in the data, track any anomalies and contextualise these anomalies on the basis of past performance and previous incidents,” Brooks explained.

This process involves detecting failures, “hidden failures” (spikes or changes in behaviour not associated with an event) and when an asset is offline from past operating data and contextualising this within what is considered ‘normal’ operating conditions. From this, data analysts create “Failure Agents” and “Anomaly Agents” to spot potential failures and watch for changes in normal operating behaviour.

Once these Agents have been trained from historical data, they are deployed to monitor live equipment feeds with all deviations labelled as anomalies and detected by the appropriate Agent.

If an anomaly does not match the signature of a deployed Failure Agent, the anomaly triggers an alert requesting an inspection to determine the cause. The results of the inspection will categorise the anomaly as either a new variation of “normal” or a new never-before-seen failure pattern.

If it is the former, the Anomaly Agent will be updated with this new information to make sure no future false alerts with the same signature occur. If categorised as a new failure, a new Failure Agent will be deployed to allow for earlier detection in the future.

The more operating data the Aspen Mtell platform ingests, the more accurate the alert system becomes and the more context the solution can provide operators. Brooks said around a year’s worth of data often proves enough to know what ‘normal’ looks like while ensuring false alerts are kept to a minimum.

In some instances, Aspen Mtell has managed to get ahead of a potential failure on certain components by 4-6 months, allowing maintenance personnel to strategically schedule maintenance procedures and reduce unplanned downtime, according to Brooks.

“Not only are we able to identify the root cause and failure mode with alerts, but we can also often provide details of exactly what is needed to fix it based on past experience,” he said. Such information is particularly useful in an industry like mining, which has an ageing employee demographic that will, in the future, need to be replaced with a new generation of personnel.

“This is all part of our vision of the ‘Self-Optimizing Plant’,” Brooks said.

The Self-Optimizing Plant, as AspenTech puts it, is a self-adapting, self-learning and self-sustaining set of software technologies that work together to anticipate future conditions and act accordingly, adjusting operations within the context of the enterprise. The plant does this through pervasive real-time access to data and information, combining engineering fundamentals and artificial intelligence, and capturing and using knowledge to optimise across multiple levels, provide recommendations and automate actions securely in a closed feedback loop.

While the mining industry is still some way off adopting such a vision, AspenTech is getting nearer to convincing the sector of its potential future worth.

Brooks provided an example from a mining company with a worldwide presence that was having difficulty with frequent production interruptions caused by unexpected equipment failures as a case in point.

This company decided to deploy Aspen Mtell across a whole site to improve the reliability and availability of equipment, boost production yields and reduce maintenance costs.

On the secondary cone crusher at the operation in question, the Aspen Mtell application gave an extreme early warning and exposed a multi-dimensional pattern showing fast incremental changes, according to AspenTech. This provided the technicians with the required insights to detect the degradation issue and take the appropriate action, avoiding operational complications that can result in production and maintenance costs in the order of $100,000-500,000 per incident.

Similarly, Aspen Mtell was able to deliver a very early lead time and warnings of a bearing issues on the cone crusher, well in advance of the vibration detection system, allowing early action to service a minor issue before a catastrophic failure. This resulted in savings of around $75,000, according to AspenTech.

Equally, monitoring and catching potential bearing problems on conveyors allowed early replacement without the extended shutdowns associated with unplanned maintenance. Such avoidance is generally worth around $1-$1.5 million in operational costs, AspenTech says.

“The net results were that the company was able to better plan and schedule service and repairs on the mobile heavy haul trucks and the static ore processing, improving operators’ safety, extending component lifetimes, and increasing equipment availability besides improving on spare part/resource planning,” it said.

“The positive results encouraged the company to expand the Aspen Mtell application to other mining sites.”

Brooks says this specific company is one of a handful of miners realising the benefits of Aspen Mtell, with the mining sector fast becoming one of AspenTech’s key growth markets behind oil & gas.

And, with AspenTech having just completed the acquisition of Emerson’s OSI Inc and Geological Simulation Software business, there could be many more mining-related opportunities on the horizon.

Sandvik offers up enhanced three-deck Doublescreen solution

Sandvik Mobile Crushers and Screens, part of Sandvik Rock Processing Solutions, has announced what it says is a new first-of-its-kind, three-deck tracked mobile plant with independent screen angle adjustment and hydraulic screen separation in the form of its QA452.

The latest evolution of the Sandvik QA Series products and three-deck Doublescreen technology, the QA452 features two triple deck inline screen boxes with equal size screen decks, each providing 9 cu.m of screening area

Sandvik Doublescreen technology typically outperforms traditional screens by up to 30%, offering a tailored rock processing solution for quarry, recycling and mining industries, Sandvik says.

Screen enhancements on the equipment include an 11% longer bottom screen deck to extract more fines.

“Featuring independent screen angle adjustment, the primary screen can be independently adjusted from the secondary screen, allowing operators to optimise their throughput, screening efficiency and product gradations,” the company said. “The primary screen performs as a fines extractor, whilst the secondary screen performs as a grader. Two processes on one plant, offering exceptional flexibility, excellent separation, accurate grading and massive throughput.”

Sandvik offers hybrid ‘e’ drive with electric plug-in on this solution, meaning operators can choose the most economical and efficient energy source. The QA452 provides a lower environmental impact due to reduced fuel consumption, and the latest powerpack on-board offers less operating noise and low emissions, according to the company. In addition, the hydraulic system has been enhanced to reduce energy wastage, and its hydraulic oil change intervals have been extended from 2,000 hours to 4,000 hours meaning up to 50% less hydraulic oil is consumed over 10,000 hours of machine usage (subject to oil sampling).

The primary screen on the QA452 can also be hydraulically separated to gain better access for maintenance and screen media changes. The addition of a new oversize cross conveyor means greater oversize material extraction, while this cross conveyor can also be reversed to allow the plant to function like a two-deck screen with oversize and mid overs discharged together.

Each screen deck features end tension screen media using Sandvik’s unique mesh tensioning system. This means faster screen mesh tensioning and removal, reducing downtime. The company’s new range of Sandvik WX rubber media, meanwhile, combines the high accuracy of wire screens with the durability of rubber, offering up to 10 times longer wear life and up to 50% faster installation time compared with wire mesh, according to the company. Having equal size panels also means the screen media is interchangeable between decks.

On top of this, thee QA452 comes with Sandvik’s My Fleet telemetry system and seven-year data subscription as standard. This offers 24/7 fleet management, geo-fencing and remote support, according to Sandvik.

Several safety features are included as standard to improve operator and on-site protection. Dust suppression spray bars, on-board water pump, safety pull cords and lighting mast are now fitted as standard for extra peace of mind.

Multotec spirals helping assess heavy minerals potential in Cameroon

Exploring for heavy minerals in Cameroon, a multinational mining company is gaining valuable results and insights through the use of an on-site pilot plant from South Africa-based process equipment leader Multotec.

The pilot plant was designed and assembled at Multotec’s extensive design, manufacturing and testing facilities at Spartan near Johannesburg, South Africa, and shipped to the remote site in central Africa last year. The containerised plant includes a range of Multotec’s own equipment including screen panels, cyclone rig and spiral rig.

According to Faan Bornman, Technology Manager: Research and Development at Multotec’s Technology Division, drill samples from the prospect area are passed over the screen to remove oversized material, with undersize going into a sump to be mixed with water to the correct density. The undersize material reports to the cyclone for desliming – the removal of very fine particles – delivering an underflow with an optimal size range of between 38 microns and 1 mm. This is fed to the spiral rig for concentration, with the spiral delivering a concentrate, middlings and tailings. The process allows the project to assess its economic heavy minerals portion, which is concentrated towards the inner section of the spiral.

“Multotec’s HX5 and 117HM spirals were employed to suit the customer’s requirement, with the new 117HM spiral showing great recovery in mineral sands,” Bornman says. “With the HX5 handling up to 5.5 t/h and the 117HM 2.3 t/h, these spirals also offer different recoveries and grade in the various heavy minerals.”

The equipment in this pilot plant is vital to achieving an accurate assessment of the deposit’s viability, but the results also give the customer important insights into how the full-scale plant should be designed if exploration proves results provide positive, according to Multotec.

“To ensure that the customer receives optimal value from the pilot plant, we sent a process engineer to site to commission the system,” Bornman says. “During the several weeks that he spent there, he also conducted training with local staff on how to run and maintain the plant.”

Kwatani customers set to benefit from Sandvik Rock Processing integration

Both local and foreign customers – as well as mineral processing OEMs looking for specialised solutions – are set to benefit from the recent acquisition of vibrating screen specialist Kwatani by global multinational Sandvik, according to the South Africa-based company.

The closing the transaction occurred late last year with Kwatani becoming part of Sandvik Rock Processing Solutions. 

The deal highlights South Africa’s world class nodes of excellence in the engineering sector, according to Kim Schoepflin, CEO of Kwatani, who says the Sandvik collaboration is a milestone for local industry. It also contributes significantly to the government’s industrialisation strategy, to foster world-class industries that can compete globally and promote job creation locally.

“The acquisition will allow Kwatani greater access into foreign markets through Sandvik’s extensive distribution network,” she says. “Our modern Kwatani facilities in Kempton Park, accredited in terms of ISO 9001:2015, is now the global engineering and manufacturing base for vibrating screens and feeders for customers.”

She adds that an added benefit for customers is the support they will receive through the Sandvik service network of engineers and technicians in the field. The proven interface between Kwatani and Sandvik equipment – for instance, a Kwatani screen feeding into a Sandvik crusher – will, the company says, add considerable value to customer’s purchasing choices.

“Customers get the best of both worlds, and can feel confident of the efficient dovetailing of our product ranges,” Schoepflin says.

Sandvik brings state-of-the-art resources which further leverage the benefits to Kwatani customers, the company says. This includes access to monitoring and automation processes as well as a depth of research and development into the application of technology like simulators.

Kwatani continues to invest heavily in its resources at its Kempton Park facilities, Schoepflin says, which employ and develop local expertise while sustaining a strong supply chain of local players. Sandvik supports this model, and shares the vision that business sustainability must be based on effective engagement, investment and commitment to the local economy. Kwatani’s local empowerment strategy supports transformation and is compliant with the South African Mining Charter.

“We work closely with local supply partners in our value chain – many of them being small businesses – to embed quality systems and manufacturing capacity,” Schoepflin says. “Customers can therefore be assured of quality throughout our products’ construction, with a reliable, sustainable and cost effective local production base.”

With its cost base rooted largely in the South African economy, Kwatani can offer customers a consistent pricing regime that is not vulnerable to frequent exchange rate fluctuations, it says. This has added to the popularity of Kwatani’s products at home and abroad, with the company twice being recognised in the Exporter of the Year awards hosted by the South African Capital Equipment Export Council (SACEEC).

“Our growth has allowed us to build our complement of competent staff, who are continuously upskilled to stay a step ahead of industry needs – with the help of our in-house training centre,” Schoepflin says.

An important indication of Kwatani’s depth of expertise and field experience is its ability to precision-engineer specific solutions for other OEMs in mineral processing. This extends to highly specialised equipment like sorters, which demand very precise feed characteristics and other protection.

“We are a partner of choice to OEMs whose equipment must operate within tight specifications, and which may have other specific requirements that a standard range of screens would not accommodate,” Schoepflin says.

Kwatani’s approach addresses the three key elements of vibrating screen performance: ore properties, screen design parameters and screening media. Its engineering solutions address all these priorities, Schoepflin says, giving customers optimal results at the lowest cost of ownership.

Metso Outotec to ‘enrich’ mining, metallurgy decision making with Geminex digital twin

The value a ‘true’ digital twin could provide the mineral processing and metallurgical industries has been spoken of continuously throughout the last few years, and Metso Outotec believes it is on the cusp of realising such value with its “science-based” Metso Outotec Geminex™ digital twin.

Designed to manage variability and optimise resources, the solution simulates and optimises seamless sustainable operations in minerals, pyro- and hydro-metallurgical processes by combining operational data from both internal and external data sources, the company says.

For simulation and production, Geminex uses the renowned HSC process models that already have over 20,000 users worldwide. These models – which combine versatile chemical, thermodynamic and mineral processing features – have been successfully implemented in hundreds of minerals and metals processing flowsheet development cases, with the same models used in plant run-time optimisation, according to Metso Outotec.

There’s more to this digital twin than the HSC process models alone, according to Veli-Matti Järvinen, Vice President, Automation at Metso Outotec.

Geminex uses “first-principle” dynamic process and equipment models for calibrated performance to help provide an ‘accurate’ digital twin for existing operations, he says.

“Here, both quality and availability of key process data are important,” he told IM, mentioning that normally available instrument and laboratory data tend to be sufficient inputs for generating the digital twin’s simulations.

And Geminex, through a series of “soft sensors”, also produces a vast amount of data that cannot be measured directly yet is leveraged through the dynamic process models, according to Järvinen.

“These soft sensors, as they are called, give an insight to the process that was not available before,” he explained, with examples including element or mineral content by particle size fractions in the process streams. This goes one step further than the feedback from, for instance, Metso Outotec’s Courier® on-stream analysers, which provide real-time elemental analysis measurements.

This makes the digital twin that much more powerful than existing solutions on the market, as it can introduce a new dataset to the equation.

And, as with all ‘true’ digital twins, the models are adapted to live data and continuously improved by machine-learning algorithms, Järvinen said.

“An example of this is model adaptation for variable ore types with different processing performance to help manage variability,” he said. “The resulting metallurgical digital twin is accurate, and its behaviour reflects the physical process.”

All this means Geminex can simulate and test alternative operational scenarios and parameters based on accurate process models and real data, providing the sort of decision-making tools the industry has been after for decades.

While the resource sustainability angle is key here – reinforced by the fact Metso Outotec has labelled Geminex as a Planet Positive product: a collection of the company’s most environmentally efficient technologies – the digital twin’s ability to use resources in an optimal way while considering both impacts and constraints is only a fraction of the industries’ value case.

The ability to incorporate new equipment and tools in a ‘live’ flowsheet that considers the specific characteristics of the orebody at hand and the conditions in which each processing stage receives material is very powerful. One can see it easily aiding the incorporation of new technology in the plant, with the simulations able to provide operators with the confidence to leverage innovations.

Järvinen says the digital twin’s use will also enable the company to start process flowsheet design that much earlier in the mine exploration/development stage.

“As soon as the customer has metallurgical data, the process can be designed and optimised to match the required economic optimum,” he said.

Metso Outotec’s strong experience in developing metallurgical processes, as well as incorporation of the process models of Metso Outotec’s HSC simulation package for minerals processing, pyro- and hydro-metallurgical processes, enables this early analysis.

“These models provide great value in the exploratory phase by enabling scenario analysis, which will help find alternatives for process flowsheets, equipment selection and even blending of different types of ore, if needed,” Järvinen said.

At the same time, Järvinen expects the Geminex digital twin to reduce the plant ramp-up time and “time to market” in the later mining project stages as operators will be that much better prepared for the likes of cold and hot commissioning.

“Great value and impact towards a positive change can be achieved in the run-time of the mining operation and the operating strategy by enriching decisions with the help of Geminex,” he said.

Geminex may be Metso Outotec’s own proprietary digital twin, but, thanks to an extensive back catalogue of process plant modelling references, it is able to run dynamic simulations that incorporate competitor equipment, according to Järvinen.

Similarly, while the company has sustainability and Planet Positive aims for Geminex, the equipment to feature in simulations does not have to be classified as Planet Positive, Järvinen says.

“The processes or assets do not need to be Planet Positive equipment, but those can become such with proper control and optimisation,” he said. “With Metso Outotec Geminex, the full value chain of mineral processing plants and hydro- and pyro-metallurgical plants are considered for Planet Positive production.”

Able to be implemented in modules, Geminex can be deployed piece by piece as part of customers’ digital transformation and continuous improvement projects, he added, opening the possibilities for Metso Outotec to leverage its capabilities beyond full flowsheet design.

In the development phase of Geminex, Metso Outotec carried out several successful pilots with universities and, now commercially available, the company has three ongoing projects in the delivery/commissioning phase with early adopters.

“These projects are already providing good results,” Järvinen said.

“With the good and growing process expertise, we are well prepared to support numerous customers with various optimisation targets in mind.”

Molycop enhances digital mineral processing position with Digital Control Lab buy

Molycop has announced the completion of the acquisition of the assets of Digital Control Lab (DCL), a provider of mill monitoring solutions based in Florida, USA.

DCL has an established market position in the cement and mining mill monitoring domain, combined with strong brand recognition, innovative engineering capabilities and a reputation for delivering a differentiated technology offering, according to Molycop.

The business offers the MillSlicer, TriSlicer and MillScan monitoring systems for SAG and cement mills. These systems are installed on customer grinding mills and provide real-time insight into the inner workings of these critical assets. These solutions have proven to reduce liner damage, eliminate obstruction spills, increase material throughput all while producing a better targeted output, Molycop says.

Jim Anderson, CEO of Molycop, says: “We are very excited to be aligning our efforts with the DCL team. This aquisition will enhance our position at the forefront of providers of digital solutions for the global mining and industrial markets. This is an exciting and important step in Molycop’s digital transformation adding industry-leading mill scanning technology and products to our current digital offering.

“Our vision is to leverage DCL’s market reputation, product offering, domain expertise and intellectual property in mill monitoring solutions, to build upon Molycop’s current technical service and digital technology portfolio, to create the premier platform for mineral processing circuit monitoring and optimisation.”

Dr Karl Gugel, DCL CEO and Founder, says: “We are very pleased to be joining a company that has been at the forefront of providing solutions to the mining industry for over a century. I am passionate about the future opportunities this transaction provides and look forward to a great partnership with Molycop.”

Multotec addresses grade control, recovery issues with RAMA sampling system

With its latest sampling system that aligns with metallurgical accounting standards, minerals processing equipment company Multotec says it now offers unprecedented levels of accuracy for effective plant optimisation.

The company’s Realtime Automated Metallurgical Accounting (RAMA™) system promises to deliver significant value by unlocking higher mineral content through improved grade control and recovery, as well as by optimising the consumption of reagents. The system brings together three sampling disciplines – metallurgical accounting slurry sampling, sub-sampling, preparation and analysis – into one solution, it says.

“By integrating our advanced samplers with a sample preparation system that meets metallurgical accounting standards, we can feed online analysers with a fully representative and accurate sample,” Modisaotsile Nyokong, Process Manager at Multotec, says. “While analysers can be accurate instruments, they cannot provide meaningful results if they are fed with inaccurate samples.”

Nyokong highlights that the RAMA online analysis feed preparation system extracts regular and full sample increments from slurry flow streams according to AMIRA P754 metal accounting standards, best practice standard and Theory of Sampling (TOS). This eliminates more than 80% of the total sampling error and allows real time process control to be conducted to the highest standard, according to the company.

“Samples are extracted from the production flow using automated mechanical samplers which are TOS compliant,” he says. “This is achieved by taking full cross-cut samples that are representative of the flow stream.”

The analysed slurry is therefore unbiased, presenting an accurate reflection of all the key parameters such as particle size, slurry density, settling velocity and mineral grade, Multotec claims. Nyokong explains that process control samplers – including pressure pipe, poppet and shark fin type samplers – have traditionally been used to feed online analysers. However, these primary samplers do not comply with the TOS, with the result that poorly represented samples are analysed with high levels of precision – a futile exercise.

“Our advantage with the RAMA system lies with feeding representative samples to online analysers, using correct sampler designs,” Nyokong says. “This produces real-time results that represent the flow stream and are free of error or statistically significant bias.”

Multotec’s slurry sample preparation solution prepares and treats each analysis stream in its own line, making it ideally suited to analysers that deal with streams individually. This avoids cross-contamination. Where multiple streams are analysed through the same analyser source and detectors, some cross contamination of streams can occur with different grades or mineral properties – undermining the accuracy of the result.

Over an analyser multi-stream cycle, the RAMA system can collect composite samples for each stream, according to Willem Slabbert, Sampling and Magnetics Product Specialist at Multotec. This means the analyser does not measure the instantaneous off-take stream ‘sample’ from the traditional in-line continuous discharge like process control samplers – which is only done about 30 minutes apart.

“Rather, it measures the performance of each stream through multiple composite samples taken over the 30-minute interval,” Slabbert says “This reduces the grade or quality variability per flow stream, and gives the plant manager a more representative monitoring of minimum and maximum process conditions – with precise values.”

The problem with ‘snapshot’ sampling of process control samplers is that stream properties can fluctuate before and after the analysis., meaning the fluctuation is not captured in the results. By contrast, the RAMA system’s composite sample accounts for all process variations over the analysis period, according to Multotec.

Slabbert reiterates that sample analysis results are only as good as the sample presented for analysis, pointing out that this applies as much to online analysers for process control as it does to conventional laboratory analysis for metallurgical accounting.

“RAMA is also a cost saving solution, as separate process control samplers are no longer required,” he says. “The samplers’ purpose in our system is doubled up for both metal accounting and for process control – without the need for any compromise.”

Configured in a containerised and modular design, RAMA is a compact and mobile system. This allows for easy installation and retrofitting into any plant operation, where it can feed any type of online analyser. It can also be readily transported and commissioned, with flexibility for expansion where necessary. Layout options are available for plants that have primary and secondary sampling with a subsequent containerised sample preparation stations, as well as for those with primary sampling only and separate secondary sampling preparation.

The RAMA system allows analysers, for the first time, to be fed with representative samples taken from the production flow stream, according to the company.

Multotec added: “The innovative combination of existing equipment with proven track record into a modular, containerised solution will bridge the gap between metallurgical accounting accuracy and accurate process control.”

Slabbert concluded: “The advantages of this novel combination of sampling global best practices into process control applications will unlock value for both analyser calibration as well as optimal, dynamic process performance.”

Botswana diamond mine feels the impact of Weba Chute Systems custom solution

Faced with a challenge of large rocks in the run-of-mine (ROM) feed regularly damaging main support structures, chutes and a grizzly feeder, a diamond mine in Botswana reached out to Weba Chute Systems to design a solution to overcome this costly challenge, which included major safety hazards.

According to Hilton Buys, Regional Manager at Weba Chute Systems, the mine’s existing chutes at the ROM section were cracking and breaking under the barrage of heavy kimberlite rocks measuring up to 1 m in diameter.

“Even the robust grizzly feeder could not withstand the impact of these rocks, which were free-falling about two metres from an apron feeder before contact,” Buys said. “Apart from the costs incurred by this damage, the transfer points were posing a significant safety hazard to mine employees.”

The solution – designed and manufactured at Weba Chute Systems’ Wadeville facility – was a special four-tonne swing door in a discharge chute, feeding from the apron feeder to the grizzly. The heavy, fabricated door is strong enough to withstand the impact while absorbing the energy of the falling rocks before allowing them to drop onto the loading section of the grizzly. The feed can then move in a more controlled manner over the grizzly into the crusher below.

“The key principle was for the door not to give way easily, thereby reducing the velocity and momentum of the large chunks,” Buys said.

There was also a design requirement to accommodate the movement of smaller rocks. This was dealt with through the addition of a second door, to also ease these rocks onto the grizzly to ensure a more gradual feed into the crusher feed chute. The success of the design, which is based on the Weba Chute Systems principle of controlled flow, has been demonstrated in the chute’s ability to operate with very little maintenance, he says. The only components needing regular attention are chute lips and swing door rails.

“We also included some specific design elements in the crusher feed chute, by installing impact rubbers,” Buys said. “Any rocks that may diverge from the main flow stream will then strike this rubber, minimising the vibration and impact on the body of the chute and are still able to drop gently into the crusher.”

Following on the success of this design, the solution was repeated at other customers’ sites, including mines in the Northern Cape which experienced similar challenges.

Kwatani adds to Northern Cape iron ore reference list with latest screening installation

South Africa-based vibrating screen and feeder specialist Kwatani will soon add another installation to its extensive footprint in the Northern Cape, this time for a new customer in the iron ore mining segment.

“We have over 1,000 screens, grizzlies and feeders in this important mining region, giving us a market share of about 95% of heavy-duty screening applications there,” Jan Schoepflin, Kwatani’s General Manager: Sales and Service, said. “With our well-established branch in Kathu, we are also able to assure our new customer of quick and highly competent service levels.”

The ore characteristics of iron ore demands mechanically robust screening equipment and Kwatani has built a name for itself in these applications, according to metallurgist Frengelina Mabotja, Kwatani’s, Head of Sales for SADC. “Our equipment is engineered for tonnage and continuous throughput, without compromising efficiencies,” Mabotja said.

Kwatani’s scope of work on the 700 t/h dry processing plant includes a 1.5-m-wide grizzly screen to remove fines from the run-of-mine material before it reports to secondary crushing and a 1.5-m-single deck scalping screen. The company will also install two 2.4-m-wide, double-deck sizing screens to separate material after secondary crushing, and five feeders to draw material from bins and stockpiles onto conveyor belts for feeding onto the downstream process.

“Our niche expertise allowed us to, once again, offer high performance sizing screens customised for this unique dry sizing application and optimise material separation by achieving the required cut size for the customer’s desired product size,” Mabotja said. “Our solution optimises the material separation while maximising efficiency and ensuring mechanical reliability for continuous and economical production.”

She highlights the depth of in-house experience – from both a metallurgical and mechanical approach– which allows Kwatani to assist the decision making of customers on equipment choice and specifications.

“Through the work of our design team, supported by our manufacturing and testing facilities, we have ensured that the solution will be fit for purpose and reliable,” she said. “The customer was also able to visit our 17,000 sq.m local manufacturing operation in Kempton Park regularly to see how we work, to check on fabrication progress and to witness the testing process.”

The equipment was completed on a tight deadline of 8-12 weeks, for delivery by year-end in line with the customer’s timeframe, according to the company.

“Our fully-equipped branch in the Northern Cape, staffed by specialists with decades of mining experience, will oversee the installation and commissioning of the equipment,” Mabotja said. “Our team will also schedule regular site visits to monitor on the equipment’s performance and condition, and advise on maintenance requirements.”

To underpin the reliable operation of all equipment supplied, Kwatani will also provide training for the customer’s maintenance personnel in the basic maintenance routines required.

Kwatani became a part of Sandvik Rock Processing Solutions late last year.

Weir Minerals’ Vulco rubber compound proves its mill lining worth

Close to four years after release, Weir Minerals Vulco® 67 rubber compound is providing exceptional wear life and reliability in mill lining systems, according to the OEM.

These abrasion- and impact-resistant rubber compounds have been developed with advanced technologies by the Weir Minerals’ team of expert engineers and material scientists who are continually refining Vulco rubber products to keep them at the forefront of mill lining systems technology, the company says.

Having identified a need for higher-wearing rubbers for mill lining systems, the material science experts commenced developing an industry leading, premium-grade rubber compound with superior wear life and performance in mill lining applications. The result was the Vulco R67 rubber – a material manufactured with proprietary new compounds and innovative methods of processing to deliver outstanding wear life and longer uptime, Weir Minerals says.

Extensive field research, compound testing and site trials were conducted to ensure it was not only able to withstand severe abrasion in typical mill system applications, but that it is best in class, the company said.

“In fact, it has been the most wear-resistant rubber compound that Weir Minerals has ever developed for mill lining applications,” Weir Minerals said. “The R67 compound boasts a high hardness, elongation, tensile and tear strength, and is suitable for lifter bars, head/shell plates and grates. When it’s utilised in conjunction with metal cap mill liners, the result is a versatile, economical and efficient product that weighs up to 50% less than steel alone.

“The added benefit is a lighter product that’s faster, easier and safer to install.”

Revolutionising wear lining

Since its launch in 2018, many mining operators from around the globe have implemented the R67 compound into their mill lining systems, according to Weir Minerals. They have reported as much as 20-40% improvement in wear life, which is resulting in fewer mill lining replacements and longer mill campaigns. This reduction in shutdowns has a dual benefit of increased cost savings and improved plant availability.

With a liner that can run significantly longer, operators have experienced a wide range of benefits including:

  • Improved wear life;
  • A measurable reduction in mill downtime;
  • Increased uptime and processing;
  • Easier and safer installations; and
  • Reduced maintenance costs.

In-field success

Extensive global trials and commercial installations in the market have resulted in several successful outcomes across a variety of different grinding applications.

As an example, a high-grade nickel and copper mining project in the US had a problem where the liners in one ball mill were wearing out too quickly, leading to continued downtime and reduced processing. The operation was looking for a product significantly superior to the elastomer it was using. Initially there was reluctance from the mine, as it had loyalty to its original mill supplier, however after Weir Minerals conducted a series of trajectory simulations and discrete modelling – to optimise the design and deliver the best process performance for the mill – it agreed to trial the R67 liners.

At the end of the trial, the R67 showed 30-40% better performance than the incumbent liners and the customer installed a full set of R67 liners in its mill.

Another trial in the US took place in an iron ore mine with several dozen ball mills in operation. Here, Vulco R67 liners delivered a 17% increase in life compared with the failed shell plates from the mine’s original mill lining system supplier. The company has since installed a complete shell liner in its ball mill.

Moving to Chile, a copper mine was keen to trial the R67 compound to see if it could improve the wear time of a competitor rubber liner. After a three-month trial, all liners were physically measured showing the Vulco R67 liners fully worn wear life projected from the actual wear would be 80% longer compared with the incumbent liners.

Another copper processing plant in Chile trialled R67 composite liners in its SAG mill against two other compounds commonly used in the industry. After 12 months, there was a 48% and 62% wear life improvement on the other liners – proving the R67 composite liners could withstand the highly abrasive environment.

Vulco R67 mill liners are made exclusively at Weir Minerals facilities in North and South America, Australia and South Africa, with plans to expand production into more regions in the future.