Tag Archives: REFLUX Classifier

FLSmidth’s digital R&D bearing fruit at the right time

As miners look for more digital solutions to ensure they can cope with the challenges that come with operating through exceptional circumstances like COVID-19, FLSmidth is leveraging decades of research and development to help them make this transition.

Terence Osborn, FLSmidth’s Director of Product and Account Management for sub-Saharan Africa and the Middle East, highlights that R&D is the lifeblood of the company’s new technologies. So much so, that it has some 80 projects underway to improve its mining-related offerings.

“The power of digital technology is certainly a key element of these efforts,” Osborn says. “Together with our Blue Box digital concept, based on our ECS/ControlCenter™, which is a cybersecure interface between our equipment and cloud data storage, we use our SiteConnect™ mobile app to monitor the performance of equipment and process plants in real time. The ECS/ControlCenter V8 process control platform sits at the heart of our digital vision, a key component in our growing portfolio of digital solutions and services that we call ENABLR.”

An example of this applied capability is an FLSmidth REFLUX® Classifier modular plant operating on a South Africa mine. Using SiteConnect, operations managers can have real-time access to over a hundred operational parameters on the plant. Data analytics linked to the cloud data can also generate time-based trends for instant viewing on the app.

“We have also developed SmartCyclone™ technology for our hydrocyclones,” Osborn noted. “This innovation uses sensors to detect wear and roping, a condition that reduces separation efficiency. By sending an alert when certain operating parameters are breached, the system ensures optimal efficiency is maintained, even as slurry conditions in the circuit vary.”

He highlights that the company’s machine-level solutions are offered as part of plant and process packages. At both plant and process level, there is also FLSmidth’s advanced ECS/ProcessExpert® solutions, which facilitate not just monitoring and control, but advanced optimisation enabled by state-of-the-art artificial intelligence technologies.

“It is important to remember that control systems need to be flexible, so that they adapt to customers’ needs and to their existing systems,” Osborn says. “With FLSmidth’s depth of expertise in software engineering and machine control, we can ensure that our machine-level systems connect with all market leading control systems – to seamlessly deliver the data that mines need for effective decision making.”

The company’s R&D pushes the boundaries of performance in a range of mineral processing fields. These include advancing its lamella plate technology in mineral separation applications, adapting its vertical roller mill for dry grinding in mining, and extending wear life of pumps with new polymers.

The fine print in FLSmidth’s REFLUX Classifier technology

FLSmidth has looked to spell out to the mining industry the benefits of its REFLUX™ Classifier (RC™) technology.

The RC is a slurry-based gravity separator designed specifically to upgrade fine minerals generally finer than 2 mm, the company says.

“The key design element is a system of lamella plates or inclined channels and the internal overflow launders. These are contained within the Lamella Settler – the top portion of the RC. The other two main components are an Autogenous Dense Medium Separator underneath the lamella chamber, and a Fluidised Bed Separator beneath that.”

Material from the process plant enters through the slurry inlet and passes over an internal over-size protection screen, removing any tramp or debris that may cause damage to the ceramic underflow valve.

Large, high-density solids quickly sink and settle in the mixing chamber in the middle section of the classifier, forming a fluidised bed of dense material. This bed is created by a series of water jets at the base of the mixing chamber and rejects any trapped lighter particles.

“Lighter and finer particles rise in the RC, through the autogenous zone to the lamella section,” FLSmidth says. “The autogenous section is created by fine suspended solids, and this zone helps convey lighter particles to the lamella section.”

This upper section contains the crucial sloping lamella channels, typically placed 6mm apart – although this distance can be reduced for finer materials. Low density particles rise up through these channels, driven by the upward water flow from the feed. The narrow sloping channels cause a parabolic flow pattern where the flow is fastest midway between the channel walls, the company says.

“The lightest particles are carried by the faster flow before they can settle and they overflow at the top of the channel. They fall into internal launders and are discharged from the RC. The higher density particles tend to slide back along the topside of the lamella channel, where the flow is slower. These particles slide down the slope, back to form the autogenous dense media zone,” FLSmidth says.

Pressure probes monitor the bed density and automatically control the underflow valve to optimise the bed level and density. The fluidised bed keeps particles in suspension and rejects the lighter material up out of the bed, while the denser particles sink and flow out through the underflow valve.

“The valve’s four-link system moves the plug vertically, which reduces wear and provides protection against splashing,” the company says.

In a recent innovation, a modular RC plant, FLSmidth selected the associated equipment – like pumps, screens, dewatering equipment and conveyors – for optimal performance. These modular plants are also automated, using advanced instrumentation and control equipment to keep operations consistent and recoveries high.