Tag Archives: Cavex

Weir adds aftermarket and service contract to Iron Bridge remit

The Weir Group says it has won a £95 million ($127 million) order to provide aftermarket components and service to the Iron Bridge magnetite project in Western Australia.

The aftermarket contract follows Weir’s success in winning a record £100 million order for original equipment for the Iron Bridge project in 2019, including its Enduron® High Pressure Grinding Rolls (HPGRs, pictured) that, it says, will enable dry processing of ore and use at least 30% less energy than traditional alternatives.

The Iron Bridge magnetite project is a $2.6 billion joint venture between Fortescue Metals Group’s subsidiary FMG Magnetite Pty Ltd and Formosa Steel IB Pty Ltd located in the Pilbara region, around 145 km south of Port Hedland.

Both the aftermarket order and revenues will be recognised over the seven-year period of the agreement, which starts in 2022, in line with the 22 Mt/y project’s initial production.

Ricardo Garib, President of Weir Minerals, said: “This is another landmark order for Weir. Having helped design an energy and water efficient magnetite processing plant, we are delighted to provide operational support for Iron Bridge from 2022. It is an excellent example of the value that Weir’s innovative engineering and close customer support can create for all our stakeholders and reflects the key role we have to play in making mining operations more sustainable and efficient.”

Weir’s Enduron HPGRs are increasingly replacing conventional mills in comminution circuits, Weir says. In addition to their energy and water savings, they also reduce grinding media consumption, while their wearable components last longer, reducing maintenance costs. Additionally, HPGRs contribute significantly to carbon dioxide emission savings.

Stuart Hayton, Managing Director of Weir Minerals Netherlands, where the Enduron HPGRs are designed and manufactured, said: “This is an important project for Weir and for the broader mining industry. We know comminution is one of the most energy intensive parts of the mineral process and, with our Enduron HPGRs, we have a unique ability to offer significant cost, energy and water savings to customers around the world. As the mining industry evolves, we are commited to continuing to innovate, reducing miners’ costs and environmental impact.”

This latest contract award means Weir now has more than £200 million of orders from the Iron Bridge project including its Enduron HPGRs, GEHO® and Warman® pumps, Cavex® hydrocyclones and Isogate® valves.

To support the project and future growth, Weir says it will build a new service centre in Port Hedland, Western Australia, thereby providing employment and training opportunities in the area, with a particular emphasis on supporting greater Aboriginal representation in the broader mining workforce.

New Weir Minerals Sand Wash Plant to boost recoveries

Weir Minerals has released a complete sand wash solution that draws on its long experience in the sand and aggregate industry.

The Weir Minerals Sand Wash Plant comes with Linatex® lining, produces more saleable product than conventional sand screw plants, with fewer moving parts, and has an optimised process that produces a drier, higher-quality product with less fines, according to the company.

The solution has already proven effective at sites like Coimbatore Minerals in Tamil Nadu, India, Weir says, where a custom-built wash plant reduced its total cost of ownership by 51%, while offering a 23% reduction in fines that helped the company consistently meet the industry’s high standards for a saleable product.

Bruce Cooke, Global Product Manager – Sand Wash Plants for Weir, said: “We know the most important thing for quarry operators in washing is recovering as much sand as possible to maximise their sales, which is why we’ve designed an integrated solution for washing their product, with a hydrocyclone which can deliver greater recovery than sand screws. In addition, every component has been selected by our expert engineers for its long-service life, interoperability and ease of maintenance.”

The compact solution features a range of Weir Minerals equipment designed for high efficiency in sand and aggregate applications, including Warman® WGR pumps, Cavex® hydrocyclones, Enduron® dewatering screens, Linatex hoses and Isogate® knife gate valves.

The Warman WGR is a popular pump in the sand extraction industry, according to Weir, combining top of the line hydraulic design with an adjustable impeller, long bearing life and a simplified wet end, making replacement predictable and cost effective.

Precision moulded and lined, Linatex premium rubber is used for wear zones throughout the plant due to its proven wear performance in wet sand applications in operations around the world, Weir said.

Cavex hydrocyclones provide “exceptional classification efficiency” thanks to their unique 360° laminar spiral, delivering more saleable product than a sand screw solution would, the company said. Enduron dewatering screens, meanwhile, reliably separate product with a high degree of efficiency. And, finally, Isogate knife gate valves contribute to the plant’s straightforward maintenance.

Surendra Menon, President, Weir Minerals India, said: “For the new sand wash plant, we focused on making it quick and easy for quarry operators to get up and running. Its straightforward design means it can be assembled in just two days while its compact skids make it easy to drag into any operation.

“Efficient, reliable and easily integrated into flowsheets, we think the plant is a game changer for quarry owners.”

Weir Cavex hydrocyclones take a load off at OceanaGold Didipio mine

The installation of 19 Cavex® 400CVX10 hydrocyclones at OceanaGold’s Didipio gold and copper mine in the Philippines has led to savings of more than $800,000/y through a dramatic reduction in grinding circuit recirculation, according to Weir Minerals.

The Didipio mine, which employs more than 1,500 workers (drawn predominantly from the local community), has expanded throughput over the last few years in line with its transition from open pit to underground mining. This increased the incumbent cyclones’ feed density beyond what they could effectively manage, leading to a circulating load of up to 700%, according to Weir.

The Cavex 400CVX10 hydrocyclones significantly improved separation efficiency due to their finely tuned spigot liner diameter and the strength and corrosion resistance provided by its cast housing, according to Weir.

Thanks to these qualities, the introduction of the Cavex hydrocyclones reduced the circulating load from 620% to 374%, with the direct savings in power consumption, ball consumption, cyclone and pump maintenance costs exceeding $815,000/y.

Gary Webb, Processing Manager, OceanaGold Didipio project, said: “Having had good performance from Cavex hydrocyclones at our New Zealand sites (Macraes and Waihi), we were confident that retrofitting Cavex hydrocyclone cluster at Didipio, with an increased number of smaller cyclones than we had at the time, would help reduce our problematic circulating load and lever multiple benefits in doing so.

“The changeover to Cavex hydrocyclones has exceeded our expectations, enabling higher throughput and lower consumable costs without being penalised in grind size.”

The performance of Cavex hydrocyclones can be attributed to the 360° laminar spiral inlet geometry design, which provides a natural flow path into the hydrocyclone, Weir said. This shape allows the feed to blend smoothly with rotating slurry inside the chamber, reducing turbulence.

Mike Arakawa, Philippines Country Manager, Weir Minerals, said: “Working with customers across the globe, our expert engineers are constantly looking at how they can maximise separation efficiency, hydraulic capacity and extend the wear life of not just the hydrocyclone, but our customers’ overall processing plants.

“I’m proud of the results we’ve achieved together with OceanaGold. Reduced circulation means reduced power draw, fewer balls consumed and less equipment wear, creating a more sustainable mine.”

Didipio produced 114,985 oz of gold and 14,999 t of copper in 2018, with 120,000-130,000 oz and 14,000-15,000 t of copper slated for 2019.

MATSA wins quick payback from Weir Cavex hydrocylone installation

Weir Minerals says the introduction of a Cavex® hydrocyclone cluster at MATSA’s processing plant, in Spain, has delivered payback in just three days.

MATSA is a modern Spanish mining company based in the north of the Iberian Pyrite Belt, a mining district that has been active for more than 2,500 years. The company, owned 50:50 by Trafigura and Mubadala Investment Company, owns and operates three mines in the province of Huelva, Spain: Aguas Teñidas and Magdalena, located in Almonaster la Real, and the Sotiel mine, in Calañas.

The processing plant, in Almonaster, recently went through a €236 million ($266 million) expansion that saw capacity go from 2.2 Mt/y to 4.4-4.7 Mt/y through the addition of a second plant. The plant now has the capacity to treat copper and polymetallic ores through three grinding lines.

Weir Minerals says it has been working with MATSA to optimise its minerals treatment plant’s primary and secondary grinding circuits.

Seda Kahraman, Regional Process Engineer Manager for Weir Minerals, said: “We have been working with MATSA for 12 years and our service team has built a solid partnership with them. We opened a service site close to MATSA and employed a full-time Service Engineer on site to provide adequate support.

“Their success is our success, and working on this particular project was both very challenging and very rewarding. They needed to increase their grinding circuit capacity from 275 t/h to 307 t/h, whilst reducing the quantity of ultrafines in the final overflow of the second hydrocyclone cluster.”

Antonio Gamiz, MATSA Plant Technical Director, said: “To maximise our plant productivity we needed a Cavex hydrocyclone cluster that was specifically designed to our application. This was achieved without an extension of the plant area and with minimal capital expenditure.”

Weir Minerals took a holistic approach to this challenge by first creating a simulation of the entire primary and secondary grinding circuit. This enabled it to visualise how the process should be running, and the most appropriate way to deliver this.

Following the simulation, the best operating conditions were calculated to support the required capacity increase and elimination of slimes, Weir said. This included the ball mills, mill liners and hydrocyclones. Using 3D laser scanner technology, the team at Weir Minerals developed a suitable layout for the equipment, including modification and steel structures.

Kahraman said:“This truly was a turnkey solution; the team had to pull together all their smarts, capabilities and tools to ensure MATSA’s grinding capacity was raised, whilst simultaneously reducing the quantity of ultrafines from their overflow. We achieved this with a range of tools and techniques including engineer design, subcontract management, and manufacturing of steel.”

To deliver the solutions MATSA required, Weir Minerals replaced the primary hydrocyclone cluster, as well as the spare parts on the secondary hydrocyclone cluster; redesigned the steel structure and walkways; installed new hydrocyclone feed pumps and piping configurations, installing and commissioning the entire project, Weir said.

The modification to the steelwork and piping, as well as the assembly of the new three-way Cavex 650CVX hydrocyclone cluster were completed in less than four days without any production interruptions, according to Weir.

Upon analysing samples from various points in the grinding circuit, it was confirmed the feed capacity had successfully increased to 300-307 t/h.

Kahraman said: “In addition to the desired increase in grinding capacity, we also improved circulating load in the primary ball mill and restored the feed pressure to the Cavex hydrocyclones to 85 kPa. We are thrilled that MATSA achieved payback in just three days due to the increase in production by 500 t/d, and achieved additional revenue of €2,751/h.”

Weir Minerals Africa on the Cavex CVXT hydrocyclone

Weir Minerals Africa says its locally-manufactured Cavex® CVXT tile lined hydrocyclone features unique laminar spiral inlet geometry designed to deliver sharper separation, maximum capacity and longer wear life.

The CVXT tile lined hydrocyclones are available in a large range of sizes to process any feed tonnage requirement, the company said. All components are designed for ease of maintenance and efficient operation, it added.

“This innovative design provides a natural flow path into the cyclone body, allowing the feed stream to blend smoothly with the rotating slurry inside the chamber,” Weir said. The result is greatly reduced turbulence through the whole cyclone, dramatically improving the separation efficiency of the hydrocyclone, according to the company. It is also offers a much longer wear life than conventional involute and tangential feed inlet designs, the company added.

The Cavex® CVXT hydrocyclone can be fitted with an extended barrel which, again, increases efficiency by increasing the residence time in the hydrocyclone. This is especially for use with ores carrying a high content of near-density materials. The hydrocyclone is also available with different overflow configuration options to suit operational needs.

To maintain separate efficiency at different operating yields and spigot sizes, a wide range of vortex finder sizes ranging from 0.4 to 0.5 are available. “These are designed to maintain a strong air-core at the different sizes. The spigot sizes range from normal to extra high capacity to accommodate low yield ores. These can also be manufactured in different material to prolong the hydrocyclone life and efficiency,” Weir said.

Weir Cavex hydrocyclones prove their worth at South Africa diamond mine

Weir Minerals’ Cavex® hydrocyclones have been put to the test at a diamond mine in South Africa’s Northern Cape Province, proving the technology can be applied in dense medium separation (DMS) plants treating diamondiferous material, according to the company.

In her presentation to the Southern African Institute of Mining and Metallurgy (SAIMM) diamond conference in Johannesburg in 2018, Weir Minerals Africa’s Senior Process Engineer, Boitumelo Zimba, said the hydrocyclones improved plant efficiency and produced 40% more tonnage than the mine’s target.

“As the Cavex hydrocyclone is tried and tested in hard-rock mining and coal classification, the Cavex 360° laminar spiral inlet profile was used as a basis for the development of a dense medium cyclone,” Zimba said. “Individual casting patterns were developed and produced in order to fabricate the Cavex dense medium hard chrome cyclone with the exact laminar spiral feed chamber that exists when moulded out of rubber.”

The customer required a solution that could offer at least six months wear-life, and a probable error of separation (Ep) of no greater than 0.08 at a cut density of 3.1 t/m³. Tracer tests were used to monitor the efficiency of the separation achieved by the Cavex hydrocyclones to ensure all of these requirements were met.

“Ep values achieved were 0.042 for the 4 mm tracer tests and 0.035 for the 8 mm tracer tests, which were below the set maximum target of 0.08 from the mine,” Zimba said. “This highlighted the benefits and improved efficiencies of the Cavex laminar spiral feed inlet.”

The lower the Ep – or probable error of separation – the more efficient the separation; it is defined as half the difference between the density at which 75% is recovered to sinks, and that at which 25% is recovered to sinks, Weir said.

“The customer’s tracer tests on the Cavex hydrocyclones showed that cut points of 3.08 t/m³ were achieved for both the 4 mm and 8 mm tracers,” Zimba said. “This was within the performance levels of 3.1 t/m³ that the customer had specified.”

Initially, the hydrocyclones were commissioned to treat only fines at the diamond plant – the minus 8+1 mm material. Later however, the mine decided to run a combined DMS, after which the full DMS size range of minus 20+1 mm was treated through all the fines DMS hydrocyclones.

“The unique design of the laminar spiral inlet geometry delivers sharper separation and maximises capacity while delivering a longer wear-life than conventional involute or tangential feed inlet designs,” Weir says. “By providing a natural flow path into the hydrocyclone body the design allows the feed stream to blend smoothly with the rotating slurry inside the chamber, reducing turbulence and improving separation efficiency.”

Zimba explained: “Combining our cone and spigot components in the hard metal range is an important contribution to the reduction in turbulence. Another vital factor is the Cavex inlet design with 360° scroll; this design was proven through extensive computational fluid dynamics analysis as well as our multiple installations to date.”

Weir Minerals also conducts ongoing research and development on methods to minimise turbulence on assembled casted components. The Cavex hydrocyclones are designed with a variety of inlet sizes to accommodate a wide top size at specified medium-to-ore ratios. The inlet sizes range from 0.2 to 0.33 as a function of the hydrocyclone diameter.

“The Cavex CVX hydrocyclone also has a wide range of vortex finder sizes to maintain separation efficiency at different operating yields and spigot sizes. The vortex finder sizes range from 0.4 to 0.5 as a function of cyclone diameter, and are designed to maintain a strong air-core at different spigot sizes,” Weir says.

To prolong life and efficiency, the hydrocyclones can also be manufactured with different materials.

“Cavex CVXA hydrocyclones are hard-wearing and are cast in 27% chromium iron for maximum abrasion resistance; components are designed for ease of maintenance, with all surfaces joined with a layer of epoxy cement,” the company says.

Weir Minerals Africa operates two foundries in South Africa – one at its Isando facility and the other at its Heavy Bay Foundry in Port Elizabeth. “This allows the organisation to cast items in-house leveraging its local foundry personnel’s knowledge, experience and expertise, ensuring that the highest standards are maintained,” Weir says.

“This approach ensures optimal life of the hydrocyclone in operation, and reduced maintenance costs by replacing worn parts in situ. It also eliminates the risk of any adverse effects on performance arising from mixing old and new hydrocyclone components. Further, safety on site is enhanced by minimising the maintenance work necessary on the installed hydrocyclones.”

Zimba said future work will include the investigation of various alloys to combat high wear rates on some of the hydrocyclone components, in particular the vortex finder and the cone sections. “This will allow longer operation and plant stability,” she said.