FLSmidth vacuum disc filters are playing a vital role in preparing tailings slurry for a backfill application at a new copper mine in the Democratic Republic of Congo.
According to Maria-Paula Lucero, sales and account manager at FLSmidth, the company supplied four 3,8 metre diameter disc filters, each comprising 14 vacuum discs. They are installed in two modules, with two units in each. This provides a cost effective dewatering strategy resulting in a cake dry enough to be mixed with cement and other additives before being conveyed underground to be placed in mined-out workings as backfill.
“The efficacy of the vacuum filter in this application allows the mine to consistently achieve its targeted level of dewatering,” says Howard Areington, general manager projects and account sales at FLSmidth. “This, in turn, means that the amount of cement and additives can be optimised, keeping operating costs down.”
Areington highlights that vacuum disk filters are the preferred technology for tailings dewatering in backfill applications, being the most cost effective form of vacuum filtration per square metre of footprint.
A range of ancillary equipment was provided as part of the scope of supply, according to Lucero. This included the liquid-ring vacuum pump with capacity to pump almost 15,700 m3/h at a pressure of 67 kPa, as well as filtrate receiver and a filtrate pump of 32 m3/h capacity. FLSmidth also supplied a 1060 gallon snap air receiver, a 750 kPa air compressor, a plant air receiver and an air drier. The water used in the filter vacuum pump needs to be potable so it was important for the design to recycle as much as possible. It is therefore recirculated through a closed circuit, with a cooling tower added to dispel heat from the water before it is re-introduced to the system.
“With disc filters delivering a drier product with more water savings, FLSmidth has provided this technology to many projects around the world,” says Areington. “With FLSmidth’s global reputation in the field for vacuum filtration backfill applications, we have secured a significant portion of this market – also supplying some of the largest vacuum disc filters in use today.”
A considerable portion of the disc filter installation was locally manufactured in South Africa, he notes. It was shipped in components to site, and installed by a third-party engineering company under FLSmidth supervision. Despite the challenges presented by the Covid-19 pandemic, the units were manufactured and delivered within a timeframe in line with the customer’s expectations.
When one of the world’s largest copper and cobalt producers wanted to double its production rates, it chose FLSmidth to provide a thickener solution that included six of its proven high density thickeners. The order was placed in 2020, and delivery has been completed.
The mine, located in the Democratic Republic of Congo (DRC), already had FLSmidth thickeners on site, and was satisfied with their performance. According to FLSmidth general manager projects and account sales Howard Areington, the company’s proposal for the mine’s expanded requirements was based on testwork to confirm the characteristics of the material that would be treated.
“The tests confirmed that we could use a similar design to what we had installed on the mine some years previously,” he says. “This solution included six counter current decantation (CCD) thickeners and one pre-leach thickener, each measuring 31 metres in diameter.”
These units deliver high solids underflow to optimise the recovery of dissolved metals. In addition to the steeper floor slope, these FLSmidth thickeners were designed with a high torque ring gear drive design, with high tolerances that make for minimal maintenance over long periods of time.
“Our high density thickener design ensures consistently high underflow densities which allows the operator to sustain high production rates and better recoveries,” he says.
These CCD thickeners are manufactured from LDX2101 duplex stainless steel. This provides mechanical benefits without compromising chemical resistance, allowing the mass of each unit to be reduced. The pre-leach thickener, which was not exposed to corrosive conditions, is constructed from carbon steel.
“We also designed and supplied five impurities removal thickeners, which are high rate thickeners, also in LDX2101 stainless steel,” he says. “The sizes of these units ranged from 20 to 30 metre in diameter.”
Fabrication of the equipment was done in South Africa, while accommodating the demands of the Covid-19 lockdown, which required careful planning and flexibility. With components and platework delivered to site, the welding and construction was conducted by the mine with installation assistance from FLSmidth and its agent in the region.
FLSmidth was chosen as the preferred provider for four large bolted thickeners for a large customer in Mozambique. Two of the thickeners are designed to reduce water load on the filters allowing for a drier filter product, while the other two thickeners recover water from the plant tailings.
The installation, which includes E-Volute™ feedwell technology for superior flow distribution, will contribute to achieving optimal water balance at the coal plant in Mozambique.
“The thickeners measure 45 metres in diameter and will control the density of material to the belt filters, improving the plant’s output,” says Howard Areington, FLSmidth’s General Manager for Projects and Account Sales in sub-Saharan Africa and the Middle East. “The design was based on the test work we conducted on the customer’s material, allowing us to determine the best thickener solution.”
He emphasises that a bolted thickener is quicker and safer to construct on-site, saving on costs and improving quality control. This suited the project’s remote location.
“The extent of welding in the construction of normal steel thickeners typically runs into kilometres,” he says. “By contrast, the amount of on-site welding required by a bolted thickener can be measured in metres.”
The four thickeners include E-Volute™ feedwell technology which improves flow distribution, leading to lower flocculant consumption, better settling rates and improved overflow clarity for the optimal performance of the thickener.
Despite the Covid-19 lockdown, good progress was made on the fabrication of the thickeners in South Africa, according to FLSmidth Project Manager Kevin Kockott. This has been managed by leveraging FLSmidth’s global resources and the design teams’ ability to work remotely.
“Our local South African office collaborated closely with our engineering hub in Salt Lake City in the United States, ensuring that our engineering work on the project was able to continue without interruption,” Kockott says.
FLSmidth has been involved with this project for almost a decade and has provided a significant portion of the coal preparation equipment. To date, this has included reflux classifier technology, pumps, screens and feeders.
The use of FLSmidth thickeners in African mining operations has continued to grow, supported by global collaboration across the FLSmidth organisation’s offices in South Africa, China and the USA.
According to Alistair McKay, FLSmidth’s Vice President for Mining in Sub-Saharan Africa and the Middle East, the company is delivering six substantial thickener contracts to mines in Mozambique and the Democratic Republic of Congo (DRC) in 2020. McKay highlights that Chinese companies have been driving much of the growth in the continent’s mining sector.
“In our work in Africa with Chinese customers, we have found that our Beijing office plays a valuable role in ensuring streamlined communication and efficiency,” he says. “This allows a constructive combination of our local knowledge with the ability of our Chinese colleagues to facilitate relationships with our customers in China.”
This differentiator has enhanced FLSmidth’s acknowledged leadership in thickener technology in the region. The company will deliver 25 new thickeners, including high rate, high density and counter-current decantation (CCD) thickeners, in southern and central Africa during 2020.
“The design work for these contracts was conducted by FLSmidth’s centre of excellence in the USA,” he says. “Given our established local infrastructure and experience in this product range, the thickeners were cost-effectively manufactured in South Africa and China.”
While the fabrication and platework was completed using local skills, the FLSmidth on-site technical support presence to construct and commission the thickeners at Chinese-owned mines in the DRC will integrate staff from the Beijing office.
“This improved communication between FLSmidth and the customer has negated the risk of any misalignment that could slow the process down,” he says. “In fact, our Beijing office has become increasingly involved in the full delivery process, fulfilling the role of the project manager. This is significant as the building of relationships across East-West contracts becomes increasingly important.”
FLSmidth offers full-service capabilities in thickener technology, he says, starting with bench or pilot scale testwork to characterise customers’ material. This informs the customer’s flowsheet and equipment selection and sizing, and the right technology application for cost-effective, optimised operation.
Mining’s accelerated move toward digital solutions since the outbreak the Covid-19 pandemic is being supported by FLSmidth’s decades of research and development.
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,” says Osborn. “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 African 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 notes. “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 AI 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,” he 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.
A comprehensive refurbishment on an FLSmidth stacker reclaimer in South Africa is preparing this giant machine for another decade of sustainable productivity.
“As OEM and intellectual property owner, FLSmidth is undertaking the mid-life refurbishment of a stacker reclaimer and tripper car for a customer in a large iron ore application,” says Buks Roodt, Director of Mining Site Sales at FLSmidth. “The extensive work programme is being conducted over two shutdown periods – one in 2019 and another one this year.”
The 2019 scope of work was carried out over three weeks, followed by commissioning and handover. After site access was authorised, the bucket wheel structure and component arrived on site and secondary structural steel fabrication was also completed timeously and delivered.
According to Gunther Guse, Manager of Mining Site Salesat FLSmidth, structural integrity repairs were carried out alongside large-scale corrosion protection. To ensure life expectancy and maintain reliability, a range of components and systems were refurbished. These included items that would normally only be exposed to standard maintenance practices and services. The integrity of electrical components was also renewed.
In addition to the bucket wheel fabrication and replacement, the full programme scope included refurbishing the long travel drive assembly, rail clamps and end buffer, as well as the hydraulic system, lubrication system and water hose reeler. Bucket wheel boom stay ropes were replaced, and the spillage conveyor was redesigned, fabricated and installed.
“An important aspect of this refurbishment contract is the installation of technological improvements,” says Guse. “Our continuous improvement process at FLSmidth leads to the introduction of components that are more energy efficient, for instance, or allow greater ease of maintenance. We are incorporating these advancements as part of the scope, reducing the client’s cost per tonne loaded.”
These upgrades, when combined with regular maintenance, can also enhance the machine’s life expectancy, extending its longevity even beyond the initial design life of about 30 years. Guse highlights that FLSmidth’s extensive capability in three engineering disciplines is being brought to bear in the project. This expertise covers mechanical, structural and electrical, control and instrumentation engineering.
On the mechanical side, the work includes components and systems such as the open gear systems, gearboxes and hydraulic systems, as well as rotating and moving parts such as trunnions and car-clamps. Structural work includes wear liners, supporting structures and areas of possible structural damage. Also, maintenance detection is undertaken including non-destructive testing for fatigue fracturing. This is done in areas where access to certain structures is not normally possible while equipment is in service.
The electrical, control and instrumentation work includes panels and drives that are approaching the ends of their useful lives. As part of the scope, variable speed drives, motor control centres and the E-house will be refurbished. Where any equipment had become obsolete, newer technologies will be incorporated.
“Our FLSmidth site engineering team had initially conducted a detailed site condition assessment,” he says. “We documented all our findings in three inspection reports – one for each discipline. These findings were used as the basis for the client’s final project scope.”
Roodt emphasises the relationship of trust between customer and OEM, which is vital to mitigate risk and ensure quality performance within demanding deadlines.
“As the OEM, FLSmidth was able to offer our premium technologies and our leading process know-how and services,” he says. “The customer could also rest assured with their direct access to the designers of the OEM equipment.”
A global track record of safe working practices while complying to the project timelines also contributes to minimised risk and smooth implementation, competitively. The scope of work during the customer’s 2019 shutdown was completed without incident or any lost time injuries.
“The customer also valued FLSmidth’s commitment to B-BBEE, supplier development and integration with the local community,” Roodt says.
The second phase of the refurbishment is planned to be carried out in the third quarter of 2020, says Guse.
“We are known for our expertise in large-scope upgrades, refurbishments and retrofit projects,” he says. “This gives customers confidence in our methodology, risk assessment, engineering support and analysis. We are also experienced in project planning, scheduling and implementation, combined with quality assurance and control, commissioning and close-out.”
FLSmidth also assays iron ore for customers and has designed and built fully automated, robotic on-site laboratories. According to Martin Matthysen, Director of Sampling, Preparation and Analysis – Mining at FLSmidth, the company independently operates and maintains sampling systems on behalf of customers.
With the general decline in ore grades in mining, FLSmidth’s market-leading expertise in mineral sampling and laboratory automation holds increasing value to mines.
“The more you understand about the characteristics of the ore entering your process plant, the better you can treat it,” says Martin Matthysen, director, SPA (sampling, preparation and analysis), Sub Saharan African and Middle East at FLSmidth. “But this needs technology that can sample high volumes, maintain rapid turnaround times, and deliver quality results.”
Only then can plant operators respond to laboratory data in real time, which is one of the keys to effective plant optimisation. With over 30 years of experience, FLSmidth has been a pioneer in laboratory systems integration, as well as driving automation in the laboratory environment.
“Our particular expertise in laboratory automation is now recognised world-wide,” says Matthysen. “This is why we have supplied 95% of all automated laboratories to the global mining industry constructed over the past dozen years or so.”
The company’s offerings address all stages of mines’ sampling and analysis requirements. It designs solutions for exploration and ore characterisation, grade control, process plants and port shipment. The highest quality equipment is sourced and applied to a laboratory solution to achieve accurate sampling, effective sample preparation and detailed sample analysis.
Each laboratory design is unique, he emphasises, as it must suit each customer’s particular operating conditions and strategic goals. The design process therefore demands close collaboration with the customer and a detailed examination of mined material and process demands. This ensures that the laboratory generates exactly the type of analytical data that the plant operators require.
“With our world-class mineral research and testing facilities, we are constantly pioneering innovations that add value to customers,” he says. “Our automated solutions also offer consistency and traceability, while improving ergonomics and eliminating hazards to laboratory personnel.”
Among the company’s innovations has been an environmentally-friendly methodology that replaces traditional wet chemistry. With no acid being used to dissolve platinum ore, for instance, the process produces no toxic waste – dramatically reducing the impact on the environment.
“We are accredited in terms of international quality standards, and work strictly to our customers’ stringent specifications regarding health, safety and environment,” he says. “Our expertise gives customers the confidence not only to procure laboratories from us, but increasingly to contract us to maintain and operate those facilities on their behalf.”
Automated laboratory leader FLSmidth has had its Operate and Maintain (O&M) contract at the Saldanha Iron Ore Terminal on South Africa’s west coast renewed for another three years.
The company has successfully operated the quality control laboratory at Saldanha – Africa’s largest iron ore export facility – for the past eight years, according to Martin Matthysen, Director, SPA (sampling, preparation and analysis), Sub Saharan African and Middle East at FLSmidth.
“An average of approximately 8500 tonnes of iron ore per hour pass by conveyor from the rail head to the ship during loading,” says Matthysen. “Our automated laboratory located above the conveyor must sample and test from this ore stream, delivering accurate and precise data timeously to stakeholders.”
He says the automated system installed by FLSmidth for a leading iron ore producer takes a representative sample of the ore and processes it though the laboratory with minimal human intervention. It is the only laboratory with ISO 17025 accreditation for the iron ore sector, complying with standards ISO 9516 for chemical analysis, ISO 4701 for particle size determination, ISO 3087 for moisture analysis, ISO 11536 for loss of ignition analysis and ISO3082 for sampling.
“Operational quality and stringent standards are vital in this process, as both the seller and the buyer of the ore must be confident that test results on the shipment are accurate and precise,” he says. “The laboratory analyses the material’s chemical composition, particle size, moisture content and loss of ignition levels – as these indicators all impact on the final price of the product.”
The accuracy of results is further checked by participating in a proficiency testing scheme as well as ‘round robin’ analysis – in which samples are verified by laboratories selected by end-customers elsewhere in the country and world.
“We are pleased to have delivered exemplary past performance at Saldanha, in service of our client’s best interests and efficient operation,” he says. “Our ongoing focus on quality has also ensured that we remain compliant with all-important ISO standards in our daily processes.”
He adds that the automated laboratory’s ability to deliver reliable and accurate results as quickly as it does, is also a vital benefit to the client.
Optimising customers’ production and maximising their return on investment is the ongoing mission of the well-resourced FLSmidth’s warehousing facility in Stormill, west of Johannesburg.
According to Derek Lane, operations manager at FLSmidth, continued investment in the facility over the past decade has kept it at the leading edge of customer service. Today, it has grown to 10,500 m2 under roof and 1,660 m2 under crane, with dual lifting capacity of up to 40 tonnes.
“We have technical capability across FLSmidth’s range of KREBS® slurry pumps, cyclones and valves,” says Lane, “allowing us to service customers through sub-Saharan Africa and into the Middle East.”
Meeting customer needs is paramount, and the operation has a strong focus on stocking strategic parts to facilitate the rapid assembly of new product. In addition to this, and central to the pump operation, is also the efficient refurbishment and retrofitting of equipment. Supporting the customer drive for lowest total cost of ownership, the Stormill facility also stocks a range of service exchange units assisting mines to maintain uptime.
Strategic stocking is done on the full range of KREBS pumps from the UMD™ heavy duty, millMAX™, split casing slurryMAX™, gravelMAX™ and vMAX™ range, all of which feature a recessed impeller design allowing the pumps to run dry. In addition, Technequip™ valves are stocked in a variety of sizes, both flanged and wafer type.
“Our workshop and warehousing capacity equip us to respond quickly to customers in various regions of Africa and beyond,” he says. “This is critical in helping maintain their operational uptime while keeping costs down.”
The quality of the FLSmidth’s KREBS pump range also allows them to be offered to customers on a trial basis. Trial pumps can be run against time or tonnage targets to ensure that they exceed the performance of existing equipment, says service manager Martin Jones.
“The service component in these trials includes a dedicated service technician who visits site for checking and fine-tuning during the trial,” says Jones. “This level of technical on-site collaboration from our teams allows operational parameters to be closely monitored and refinements made to specific performance requirements.”
An important cornerstone of FLSmidth’s customer support strategy is closely aligned with the operational drive by mines to achieve the lowest operating costs possible. Jones says that by providing a range of service support options for all new products supplied, the company is able to add value to mine sites. Within South Africa, service support options include regular visits by service technicians to site, as well as more intensive levels of service in the form of Bespoke maintenance contracts, and field service support teams operating in strategic locations.
“Some customers request a period of commissioning assistance, for example, and we can provide experts on site for as long as the customer requests them,” he says.
Lane highlights the importance of regular and correct maintenance of equipment to minimise lifecycle costs and maximise productivity. To meet this goal, FLSmidth conducts customised training on request for customers. This could be focused on hands-on maintenance staff dealing with essential day-to-day maintenance. It is also available for higher-level staff such plant engineers, on topics such as product selection. The training can even be delivered in different languages, suited to the region.
The large stockholding of spares at Stormill for pumps, cyclones and valves is based on historical and forecasted customer consumption. Key customers also hold strategic consignment stocks at their sites. These are currently located in Zambia, the Democratic Republic of Congo and Tanzania, as well as with an agent in South Africa’s Northern Cape province.
“This allows us to have the stock as close to the customer as possible, to optimise availability,” he says.
He emphasises that all the Stormill facility’s activity is strictly governed by recognised international standards. The operation is certified with ISO 9001 for quality, ISO 14001 for environmental management and OSHAS 18001 for safety and health.
Engineered to be adaptable to almost any situation, FLSmidth Buffalo™ Feeder Breakers are as reliable as they are efficient – even in harsh operating conditions.
A major advantage offered by the FLSmidth Buffalo Feeder Breaker to mining operations is its modularity, according to Leon Kemp, Global Product Line Manager for Buffalo Feeders and Feeder Breakers at FLSmidth.
“The modular design allows the FLSmidth Buffalo Feeder Breaker to be adapted for specific applications on the mine,” says Kemp. In an application on a potash mine in Chile, a recently developed low tonnage reclaim feeder breaker was used to accommodate a feed rate of between 132 tph and 160 tph, with a top feed size of 500 mm.
“Our design allowed the unit to handle potash with a bulk density of 1,600 kg/m3 and an inherent moisture content of 10%,” he says. “The versatility and flexibility of this solution was a key factor in the customer’s choice.”
This FLSmidth Buffalo Feeder Breaker is designed to operate without any civils infrastructure, which enhances its versatility in a mining operation. This means ease of movement and installation, while achieving the required discharge heights.
“The modular design of the feeder allows numerous discharge heights to be achieved by simply configuring the quantity of neck modules to facilitate the required discharge height,” he says. The unit at work in Chile has a deck width of 1200 mm, a length of 5 metres and a discharge height of 2,64 metres.
The FLSmidth Buffalo Feeder Breakers are produced under stringent quality control at FLSmidth’s substantial manufacturing facility in South Africa, which holds ISO 9001:215, OSH 180001 and ISO 14001 accreditations.
“This brand has a strong established reference base of units operating in similar applications globally,” says Kemp. “This allowed the customer to benefit from a productive collaboration between FLSmidth’s South African operation and its Chilean office.”
The feeder breakers are easy to transport in standardised containers. This unit was shipped from South Africa to Chile and assembled on site. The economy of the design also meant that fewer workers were required for assembly and commissioning.
The heavy-duty design features replaceable individual parts throughout the full length of the feeder. Flow control is achieved through adjustable hydraulics, variable speed drives and gearbox ratios. The hydraulic take-up system ensures ideal and consistent chain tensioning on the shaft take-up assembly. The motor control centre, which incorporates a variable speed drive, is located on-board the reclaim feeder; only the power supply needs to be isolated before relocating the unit.
“With auxiliary components such as wheel assemblies, lights, lubrication systems and safety features, the FLSmidth Buffalo low-tonnage Feeder Breaker is a true fit-for-purpose solution,” he says.