Tag Archives: Johannesburg

SEW-EURODRIVE South Africa gears up for local growth with new headquarters

SEW-EURODRIVE South Africa, a specialist in drive and control technologies, has moved into its new state-of-the-art 26,000 sq.m headquarters complex in Aeroton, Johannesburg, in the process, more than tripling the floor and factory space that was available at its previous premises.

Built and equipped at a cost of R200 million ($11 million) and modelled on SEW-EURODRIVE’s showcase factory in Graben-Neudorf, Germany, the facility – which accommodates some 150 employees – makes extensive use of the latest technologies to effectively network people, processes, services and data.

The investment reflects SEW-EURODRIVE’s confidence in the future of both South Africa and the African continent, it said.

Commenting on the investment, Raymond Obermeyer, Managing Director of SEW-EURODRIVE South Africa, said: “This is a bold step that demonstrates our commitment to being part of solving South Africa’s problems and developing the economies of countries across Africa.”

SEW-EURODRIVE currently services 23 countries throughout the African continent from South Africa.

“With the implementation of the African Continental Free Trade Area (AfCFTA) protocol, which came into effect in early 2021, and a push to grow manufacturing on the continent, we are expecting African markets to account for around 50% of our turnover within the next few years,” Obermeyer says.

The new facility will play a pivotal role in allowing SEW-EURODRIVE to service the burgeoning Africa market efficiently, it says. The headquarters houses not only the group’s African head office but also an assembly plant for industrial gears and electric drives, expanded central warehousing and repair facilities. It also encompasses assembly and repair of all variable speed drives (VSDs), AGVs and Servo motor technology. SEW-EURODRIVE also employs multiple mechanical, electrical and mechatronic engineers to further support technical customer queries.

In addition, it accommodates SEW-EURODRIVE’s Drive Academy, which delivers product awareness and maintenance training to customers. Online and virtual augmented reality training and support is also now available, in direct support of SEW-EURODRIVE’s social development plans.

The expanded warehousing gives SEW-EURODRIVE the ability to increase stock levels, a huge benefit given the problems currently affecting the global supply chain. It means the company’s customers in Africa will be able to able to get orders – for new equipment or spares – fulfilled with minimal delay, according to the company.

The expanded warehousing gives SEW-EURODRIVE the ability to increase stock levels, a huge benefit given the problems currently affecting the global supply chain

“The new facility allows us to service our customers more efficiently, reducing the high cost of unplanned downtime and allowing them to adhere to their scheduled maintenance programmes,” Obermeyer states. “Ensuring our customers’ continued productivity has been the key driver behind the development of our new premises.”

Over a three-to-five-year period, SEW-EURODRIVE will incorporate further 4IR technologies, including automated assembly machines and guided vehicles, into the Aeroton factory at a cost of an additional R200 million.

“We are working hard to shape the factory of tomorrow with system solutions for Industry 4.0 and a focus on raising productivity and implementing smart maintenance while, at the same time, providing ergonomic support for the people working in these facilities,” Obermeyer says.

SEW-EURODRIVE has used its own technology to automate operations at the Aeroton facility, with the main production conveyor being based on the company’s high-tech MOVI-C® all-in-one modular drive solution which is now being introduced to the African market. MOVI-C had its official African launch at the recent Electra Mining Africa 2022 show in Johannesburg.

In essence, MOVI-C is a suite of products – which includes controllers (PLCs), VSDs, gear motors and servomotors – that automates drive applications, whether they be simple or very complex.

The installation – which has resulted in a 40% productivity gain – includes the MOVIGEAR® mechatronic drive system. The MOVIGEAR units – which combine an energy-efficient IE5 motor, gear unit and corresponding drive electronics in a single housing – control and drive the production conveyor. The modular nature of the installation means it can easily be extended in the future should the need arise.

The assembly line for geared motors can accommodate 7,000 units per month while assembly of industrial gear (IG) units is currently being ramped up to between 100 to 140 IG units per month, doubling current capacity. New spray booths and automated oil filling stations have been installed to cater for these volumes.

All local assembly is conducted in accordance with SEW-EURODRIVE’s global quality standards, with the assembly of VSDs, servo motors and other sensitive equipment being conducted in an isolated clean area – with copper grounding and anti-static mats – of the facility. The assembly and logistics processes are also now incorporated into SEW-EURODRIVE’s SAP system, which gives better traceability and visibility of all orders as they move through assembly processes.

Among the products to be produced at the new facility are SEW-EURODRIVE’s modular air-cooled condenser (MACC) drives, which have already experienced excellent sales in South Africa with two units having been installed recently in the Northern Cape and a further 24 units at a Limpopo site, the company said.

Forming part of SEW-EURODRIVE’s M-Series modular IG range, the MACC is a purpose-designed gearbox solution for driving the modern fan-based air-cooled condenser systems used in steam-driven power generation units.

SEW-EURODRIVE will stock a single casing size with multiple components and specific ratios depending on which power station requires the drive. This modular approach will enable the new facility to custom assemble MACCs at a rate of approximately two to three units a week, drastically cutting the long lead times typically associated with equipment of this type.

Other notable products to be locally assembled include the New Generation X.e Series industrial gears; the P-series planetary industrial gears for high torque mining applications; short importation and commission lead times for mill drive solutions with power packs; electric motors; and the customised single-stage M1 range of speed reducers, which consists of 37 options for fine tuning a drive’s output speed and torque.

Illustrating the benefits of the new Johannesburg facility, SEW-EURODRIVE anticipates being able to assemble and test customised M1 units within two to three weeks from an order being placed. Previously they had to be imported from overseas with lead times of between 16 and 20 weeks.

FLSmidth, Kwatani, Multotec and Zest WEG set for Electra Mining Africa

Major domestic and international mining equipment suppliers are gearing up for Electra Mining Africa in Johannesburg, South Africa, with FLSmidth, Kwatani, Multotec and Zest WEG just some of the names set to show off their offerings from September 5-9.

MissionZero on show

FLSmidth will be using this year’s exhibition to demonstrate the progress it is making in realising its MissionZero strategy, an ambitious program that aims at allowing mines and process plants to achieve zero emissions, zero water waste and zero energy waste by 2030, it says.

One of the innovative products to be featured on the stand includes its REFLUX® Flotation Cell (RFC). “This draws on FLSmidth’s established REFLUX technology, which has been in the industry for many years now and has proved outstandingly successful, particularly in the coal industry,” Alistair McKay, FLSmidth Vice President for Mining in Sub-Saharan Africa, Middle East and South Asia, said. “The RFC brings together the REFLUX concept with flotation technology and will allow process plant operators to start recovering the smaller fractions in their ore feeds, as well as introducing coarse flotation into existing systems.”

McKay adds that the RFC is now at an advanced stage of development and that FLSmidth is hoping to have a pilot plant operating in South Africa before Electra Mining Africa.

FLSmidth has many existing products and technologies that are already contributing strongly to MissionZero. Among them are its SmartCyclone™ solution, which automates the monitoring and control of cyclones; LoadIQ, a product that uses a system of smart sensors and artificial intelligence-based software to determine the optimal load in SAG mills; and its EcoTails™ system, developed in collaboration with Goldcorp (now part of Newmont), which blends filtered tailings with waste rock to create a geotechnically stable product called GeoWaste, which can be used to fill excavated areas.

While FLSmidth is a global group, much of the equipment that will be featured on its stand is produced in South Africa, either in whole or in part, at its Delmas Super Center, which manufactures vibrating screens; feeders, breakers and sizers; and polyurethane screening media and flotation parts.

Kwatani’s new age of efficiency

Kwatani plans to come to the Johannesburg Expo Centre ready to cast the spotlight on its modern multi-slope screen design and its strides in digital innovation.

While multi-slope screens – generally known as ‘banana’ screens – have been available since the 1980s and are, therefore, not necessarily new to the market, Kwatani has, in recent years, ushered in a whole new approach to the design of these screens, according to CEO Kim Schoepflin.

“Traditionally, multi-slope screens have always been renowned for their high velocity,” she says. “While the high velocity translates into high capacity, the downside is the resultant screening inefficiency and the high wear rate of the panels, which in turn translates into high maintenance costs.”

Kwatani can design its screens to perform efficiently at a lower building height and fit into existing screen infrastructure. The lower physical height of the screen also impacts the capital cost of complementary equipment such as pumps.

Apart from its leading-edge multi-slope screen design, Kwatani will also showcase its advances in the digital space. Digital technologies, says Schoepflin, have the potential to unlock new ways of managing variability and enhancing productivity. The miniature version of the Kwatani multi-slope screen to be displayed at Electra Mining Africa will, therefore, be digitally-enabled.

Kwatani COO, Kenny Mayhew-Ridgers, added: “We approach digitalisation in two ways. We believe that sensors are the starting point, as they are where data is created. Embedding sensors in plants, which in turn churn out large volumes of data for analysis, is increasingly attainable.”

Schoepflin continued: “The second scenario is the cloud environment, which is gaining strong momentum across the industry. As mining companies digitally transform, they simultaneously expect greater control over their data with all the benefits of a cloud experience. At Electra Mining Africa, we will, therefore, showcase these two scenarios – sensors with a PLC/SCADA and control room environment, as well as a cloud solution.”

The company also plans to highlight how the recent acquisition of Kwatani by Sandvik further advances its innovation drive, Schoepflin says.

“Leveraging Sandvik’s substantial experience in this field, Kwatani will further drive its digital offering, thus ushering in a new age of efficiency and winning the productivity and cost-control battle for our customers,” she concluded.

Multotec to showcase ESG-focused offering

Multotec has exhibited at every Electra Mining Africa exhibition since the show was launched in the 1970s. As usual, it will have a strong presence at this year’s event, with its in-house experts on hand to brief visitors to the stand on the company’s line-up of minerals processing equipment.

“Given that the Electra Mining 2020 was cancelled due to COVID, we see this year’s show as an excellent opportunity to reconnect with our customer base,” Rikus Immink, Multotec’s CEO – South African Operations, said. “The overall theme will be how our equipment and systems can assist customers in realising their environmental, social and governance (ESG) goals. We will also be emphasising our strong commitment to South Africa. We are a global group now, but we started in South Africa and the country still accounts for about half our revenues.”

Virtually all Multotec’s products can, to an extent, reduce consumption of resources such as water and energy and allow for more efficient operations, the company says. A prime example is provided by the pulping chute, a highly innovative concept in fines scrubbing first installed at Ekapa Minerals’ Combined Treatment Plant (CTP) in Kimberley in late 2019. More recently it has been successfully trialled at a diamond mine in Botswana. “We are very proud of this innovation and it will feature very strongly on our Electra Mining stand,” Immink says.

Other Multotec products to be highlighted at the show and which are able to contribute to energy and water saving include the company’s classification cyclones, which provide efficient solutions for desliming and dewatering; its ultra-fines spirals, which offer a non-chemical process for fines recovery and allow easy water recovery; its centrifuges and filter presses, which deliver effective solid liquid separation and dewatering solutions; and its screening media, whose many benefits include the recovery of non-chemical water.

Immink also notes that Mato belt cleaners, which will also feature on the Multotec stand, prevent spillage and reduce clean-up requirements. “This is not a product that gets much attention and yet it can play an absolutely crucial role in cutting wastage and in maintaining a clean environment,” he said.

The Multotec products that will be showcased at Electra Mining Africa 2022 are manufactured in South Africa, primarily at Multotec’s extensive facilities in Spartan, Johannesburg, with an accredited local content certificate from SABS.

Zest WEG focuses on efficiency, sustainability

After a decade-long expansion of its manufacturing capabilities in South Africa, Zest WEG, the South Africa-based subsidiary of Brazil’s WEG Group, says it is well placed to extend its already extensive footprint in the African market.

“We now have six manufacturing facilities in Gauteng and Cape Town, producing a wide range of equipment including gensets, transformers, electrical panels, E-Houses, MCCs and mini sub-stations,” Zest WEG’s outgoing CEO, Juliano Vargas, says. “This ability to manufacture locally gives us a huge advantage in the African market, as we can produce economically and deliver promptly to countries throughout the sub-Saharan region.”

Most of Zest WEG’s product offering will be on display at the Electra Mining Africa 2022 exhibition.

Vargas’s successor as CEO of Zest WEG, Eduardo Werninghaus, said: “Our theme, as always, will be how to change energy into solutions. There will, however, be a particular emphasis on efficiency and sustainability.

“One of the products that we’ll be highlighting is our range of WEG IE4-rated super-premium efficiency electric motors which were launched locally last year and which cost no more than their IE3 predecessors. These are the most energy efficient motors in the market and offer major operating cost advantages to users.”

Werninghaus says that the WEG IE4 motors have already received a warm reception from the mining industry, which is struggling with constantly rising electricity costs. “A medium-sized mine typically has between 2,000 and 3,000 electric motors on site – powering everything from fans and pumps to conveyor belts and screens – so the potential for very significant energy and cost savings is huge.”

Werninghaus adds that Zest WEG will also be showcasing many high-tech products and systems at the show. These include the already available WEG Motor Scan, which allows the continuous monitoring of electric motors and other rotating machines; and Pump Genius, a software package that enables a standard VSD to be dedicated to specific pumping systems with various motor and pump combinations, thereby providing improved control and monitoring capability.

Also on show will be WEG’s new Motion Fleet Management system, which uses artificial intelligence and machine learning to diagnose and monitor rotating equipment such as motors, VSDs, gearboxes and compressors. Based on cloud computing technology, the performance of assets can be monitored at any time from any part of the world. This approach reduces unplanned downtime and optimises repair actions.

“Keeping abreast of digital developments is a priority for us and Electra Mining Africa will give us an opportunity to show just how far we’ve come on our digital journey,” Werninghaus concludes.

Sandvik reinforces commitment to southern Africa miners with new South Africa HQ

In a strategic move that, it says, will consolidate its resources and further enhance its service to customers, Sandvik Mining and Rock Solutions has moved its South Africa headquarters to brand new, purpose-designed premises in Kempton Park near Johannesburg.

According to Simon Andrews, Managing Director at Sandvik South Africa, the state-of-the-art Khomanani facility includes three large workshop areas and office space on a 62,000 sq.m site.

“As the Tsonga name Khomanani reflects – ‘hold each other together as a unit’ – our new home unites us under one roof to collaborate, adapt and learn as we strive towards higher standards,” Andrews says. “The technical synergies of the workshops add to our commitment and capacity for local production that meets global quality requirements.”

Two of the workshops are dedicated to refurbishment and rebuilding of local equipment for the southern African region – mainly Botswana, Namibia and South Africa. This is where new standard-format equipment is configured for local use – typically including features like safety systems, lighting, toe-hitches and decals to customer specifications.

“Our remanufacturing facility allows us to completely rebuild machines to OEM standards, including the sub-assembly refurbishments on transmissions, axles, differential and pump motors,” Andrews says.

The first workshop has 23 bays for machines to be refurbished, while the second is specially equipped with 100 t capacity flooring for the heavier tracked equipment such as underground continuous miners and surface drill rigs. The layout of the site allows the heavy transport vehicles to loop in and out with equipment without needing to manoeuvre, improving workflow and efficiency, the company says.

A combination of cranes from 5 t to 30 t capacity – as well as a specialised 50 t forklift – facilitate safe and quick off-loading and reloading.

The third workshop focuses on local assembly of equipment for both South Africa as well as global markets to Sandvik’s OEM standards.

“Our investment in local manufacturing capacity is an important vote of confidence in South Africa and its mining sector,” Andrews says. “The quality of our work is also world class, allowing Sandvik to shift certain manufacturing duties from elsewhere in the world to our new facility.”

In line with Sandvik’s international guidelines, the design of Khomanani prioritises energy and water efficiency. With a shared solar photovoltaic system and use of LED light bulbs, the building is expected to achieve a 48% saving on energy, also making greater use of natural light, roof insulation and ‘low-E’ coated glass.

Water-efficient fixtures, fittings and systems, as well as rainwater harvesting, will improve water consumption levels by 42%, according to the company.

Tronox boosts mineral sands dredging process with help of IPR-supplied SlurrySucker

Following a successful one-week trial, heavy minerals company Tronox Mineral Sands has taken delivery of a SlurrySucker dredging unit from Integrated Pump Rental.

The SlurrySucker will remove sand from the process dams near the Tronox mining operation on South Africa’s West Coast. This installation enhances the safety and efficiency of the dredging process, which previously had to be carried out manually by a team of underwater divers, IPR said.

“The pumping capacity of the dredging unit will ensure optimal operation of Tronox’s dams which need to be kept at the required storage volumes at all times,” Ruaan Venter, Rental Development Manager at Integrated Pump Rental, said.

The dredging unit will assist Tronox in regularly cleaning sediment from its process dams, reducing the risk of pump blockage or failure. This solution aims to provide rapid results on a cost-effective basis, while the remote operation raises safety levels, the company added.

To withstand the corrosive effects of salt water, the SlurrySucker has been equipped with a stainless steel casing as well as stainless steel components including wear plates and impellers. The units were manufactured at Integrated Pump Rental’s facility in Jet Park, Johannesburg, South Africa.

The SlurrySucker dredging unit comprises a floating barge with an electric hoist operated from the side of the dam. This ensures a high level of safety with the barge being operated remotely, including the lifting and lowering of the pump. At Tronox, the SlurrySucker is designed to pump 150 cu.m/h of sediment – with a solids content of 50% – back to the thickener in the plant.

“The electrically-driven unit also makes sure that there is no risk of contaminating the water in the dams with diesel or oil leakage,” Venter says. The compact unit is easy to transport between the dams requiring dredging, making for optimal usage of the equipment.

With its local manufacturing capability and technical support offering, Integrated Pump Rental says it is well equipped to maintain the SlurrySucker out of its Johannesburg facility.

Multotec liners scrub up nicely for Morocco phosphate mine

In one of its largest scrubber installations to date, Multotec Rubber is helping a phosphate mine in Morocco achieve new levels of efficiency thanks to the installation of customised liners.

The scrubbers measure 6.5 m in diameter and 11 m in length – large dimensions necessitated by the process plant throughput of 12 Mt/y. The installation, conducted during the March quarter of 2019, was carried out in response to a serious challenge faced by the customer. The existing head plates were wearing out at double the rate of the shell plates. This was leading to additional maintenance shutdowns during the life of the liners, with associated extra costs.

According to Mohamed Trabelsi, Senior Sales Engineer at Multotec Rubber, the collaboration with the customer included sending a Multotec team to site to first assess the situation. Multotec already had a longstanding relationship with the customer at this process plant, with Multotec trommel screens having operated successfully at the plant for over three years.

“Our team of engineers were on site to gather vital operating information including throughput tonnages, particle size, charge levels and rotational speed,” Trabelsi said. “We also assessed the variable speed drive system.”

This data was processed using the Rocky DEM simulation software, in which Multotec Rubber has made a significant investment. Leveraged by engineers, this software can simulate the full lifecycle of liners and predict when the scrubber will no longer perform efficiently, according to the company.

Rocky DEM allows engineers to accurately simulate all operating parameters in the scrubber. These include the shape and size of ore particles in the slurry being fed into the scrubber slurry, the charge level, the linings, attrition rates, particle trajectories and the scrubber’s rotational speed, Multotec Rubber says.

“We can therefore simulate the actual operating conditions of the scrubber, as well as the performance of the head and shell liners,” Trabelsi said. “Upon our assessment of the results, it was found we needed a different configuration of liners to the previous one in this application. In fact, the solution was a uniquely designed liner configuration – quite different to what is traditionally used.”

He notes that, in Multotec’s experience of high throughput scrubber applications, it is critical to lift the material away from the head plate, thereby alleviating the sliding abrasion which causes excessive wear.

“Our objective was to ensure optimum wear life with the lowest total operating costs,” Trabelsi said. “Efficiency was enhanced by ensuring that the liner profile configuration was suited to the specific operating conditions. By doing this, the wear life in this application has been improved.”

Since installation, the liners have been performing in line with the customer’s expectations and are expected to have a lifespan of over five years. These lifecycle predictions also allowed the payback period to be accurately determined, assisting the customer in making the best operational and financial decision, the company said.

The liners are locally manufactured at Multotec Rubber’s ISO 9001:2015 facility near Johannesburg, South Africa, which has benefitted from continued investment in technology over the years, the company said.

“Our quality manufacturing facility expedites the production of liners engineered for individual applications,” Trabelsi said. “The entire process from design stage to installation took just 12 weeks – in response to the urgency resulting from the premature failure of the previous scrubber lining installation.”

Trabelsi also noted that – even after finding an appropriate solution – mines must constantly anticipate changing conditions in their process plants.

“As mines develop, the orebody changes; this brings changes to their throughput capacities and mill operating parameters,” he said. “If a process plant has liners that have run for 10 years, it is not necessarily a given that this liner configuration is still suitable for the application.”

He emphasises that it is critical to conduct an assessment exercise in every application, before quoting on a replacement liner. Most importantly, the liners should be engineered in accordance with the current operational parameters of the mine.

“This is why Multotec Rubber considers it so important that our engineers go to site and assess the actual mill operating data for themselves,” he said. “This makes it possible for us to gain access to the information from the plant operating system, so that the best solution can be engineered for the mine.”

Correctly designed liners will offer greater energy efficiency and reduce media consumption, according to Trabelsi. This is significant, as energy input and media consumption account for around 80% of the grinding costs in the plant – depending on the application.

“The more we are able to simulate, the more accurate information becomes available,” Trabelsi said. “We are then able to accurately predict the savings and payback period that could be expected at the plant – as a result of improved efficiency and reduced power consumption per tonne.”

ERP system ups inventor accuracy at Weir Minerals Africa’s Kitwe facility

Weir Minerals Africa’s newly upgraded Kitwe facility in Zambia, its hub for central and east Africa, is benefiting from the use of an enterprise resource planning (ERP) system that has seen inventory accuracy rates rise, according to the company’s Luhann Holtzhausen.

The branch officially opened in early 2018 and boasts a state-of-the-art logistics and supply chain management systems to match those at Weir Minerals Africa’s main distribution hub in Alrode, near Johannesburg, it said.

Luhann Holtzhausen, Weir Minerals Africa Supply Chain Director, said: “Our Kitwe branch now has a 100% location-controlled warehouse that runs off our ERP system with Wi-Fi-enabled scanners in place. This has resulted in the achievement of inventory accuracy rates in the high 90s.

Holtzhausen continued: “The technology and technical capacity in this facility enables us to pick and bin items in real time. This will match any other system that customers may have seen globally and is also a benchmark within Zambia.”

The new warehouse is all under one roof, with high visibility through natural and artificial lighting, where every product is clearly labelled with bin location and barcodes for easy tracking, Weir said. Shelving of up to three metres high keeps all items neatly stacked, easy to identify and quick to retrieve.

“The right goods in the right quantity in the right place means that when a customer asks for an item, we know that we have it and can find it without delays,” Holtzhausen said.

As part of the company’s operation-wide system, the stockholding of the Kitwe warehouse can be viewed in real time by the supply chain management team in Johannesburg. Holtzhausen emphasised the importance of the ERP system’s ability to track trends in customer usage in a systematic and methodical manner, to avoid any stock-outs on mine sites.

Lack of timeous access to spare parts and equipment can be costly in terms of operational downtime, particularly at remote mines that take time to reach, Weir said.

“In addition to the high accuracy of our data on warehouse inventory, our systems also give us end-to-end velocity measurement to monitor the flow of goods from receipt at our warehouses to the actual time of delivery at the customer’s location,” Holtzhausen said.

Weir Minerals Africa has 75 stocking locations across the southern and central African region, and ships nearly 100,000 items each year from its main distribution hub in Alrode.

ANDRITZ pumps draining flooded mining tunnels in South Africa

Just as IM’s water management feature goes live, ANDRITZ has released details of a project it has been working on to de-water old mines in Johannesburg, South Africa.

South Africa has been dealing with an acid water problem in recent years. Underneath the old gold mining city of Johannesburg is a lake containing heavily contaminated water, which spreads horizontally and vertically into the abandoned pits of the former gold mines, according to ANDRITZ.

The water line has reached a critically high level, as determined by the specialists from the ANDRITZ subsidiary, ANDRITZ Ritz, in Schwaebisch Gmuend, Germany, which was given the first order to drain the mine water back in 2010.

The execution of the project was delayed by four years, however, and it was only in Spring 2014 that two powerful ANDRITZ submersible motor pumps were installed in the middle of Johannesburg city centre, in the so-called ‘Central Basin’. Each pump is capable of bringing 1,500 m³/h (1.5 million litres per hour) of water to the surface, according to ANDRITZ; with 60 million litres of water per day pump, it is a never-ending task, ANDRITZ said.

“In Johannesburg, however, acid mine water is an ongoing problem. Rainwater seeps into the tunnels and reacts chemically with residual minerals like pyrite, producing corrosive sulphuric acids. In the worst case scenario, this can result in a pH value of 2, which is enough to cause lasting damage to humans and the environment.

“Because of this corrosive acid, the Johannesburg pumps had to be completely redesigned. The design is based on ANDRITZ’s proven HDM (Heavy Duty Mining) technology, which uses the concept of a double-suction pump. The thrusts produced are offset by the counter-rotating arrangement of the impellers and the pumps run without axial thrust, giving a properly maintained pump a service life of 10 to 15 years.”

The pumps for the Johannesburg project are a tailor-made, customised design built for this special individual application, according to ANDRITZ. Part of the new system is an encapsulation of the submersible motors (see top photo), which enables the creation of an internal pressure higher than the external pressure. This prevents the intrusion of the corrosive water and the components inside the motor being attacked and possibly destroyed. “At the same time, the water being drained is used to cool the motor by means of a heat exchanger,” ANDRITZ said.

ANDRITZ engineers spent weeks developing the sophisticated technology needed to encapsulate the motor so it could withstand the higher internal pressure. The first two pumps have been running since June 2014. These 21-t pumps, each 15 m long with a 1-m diameter, were installed side by side in March, 5 m apart, but could only be started after completion of the water treatment plant.

Freely suspended on 430-m-long duplex steel pipes, they transport the acid mine water to the surface and onwards into an adjacent treatment plant (pictured). Here, through the addition of lime, the pH value is raised, the acid is neutralised and the heavy metals dissolved in the water are absorbed and precipitated as hydroxides, ANDRITZ said.

The South African authorities are planning a total of three pumping stations, which will each be developed at the mines’ disused extraction shafts. In addition to the Central Basin in Johannesburg’s city centre, invitations to tender for the ‘Eastern Basin’ and the ‘Western Basin’ are currently in progress, according to ANDRITZ.

“The long-term goal is to force the water level in the flooded mines back from its current level of approximately 200 m to a depth of 1,000 m, and to keep it there, to then be able to begin mining gold and gold ore in the drained upper layers of the mines once again,” the company said.

Weir Minerals Africa’s supply chain efforts providing miner payback

Weir Minerals Africa has been upgrading its supply chain system over the past four years and the company says its mining customers are feeling the positive effects.

According to Weir Minerals Africa’s supply chain director Luhann Holtzhausen, the company ships almost 800,000 bespoke items each year from its main distribution hub in Alrode, near Johannesburg, South Africa.

Leveraging both modern technology and an innovative management approach, it has raised its warehouse stock accuracies to 98% over the past four years, above the global benchmark of around 95%, the company said.

Holtzhausen said: “Our streamlined supply chain management ensures 70% of our products and components are delivered within two weeks of a sales order being received. Our inventory accuracy has also raised the on-time delivery performance over the last year above 90%.”

Between 3,000 and 5,000 parts are shipped each day from the Weir Minerals Africa Alrode facility. These volumes have grown 20% year-on-year since 2016, which the new systems can still comfortably manage in a single-shift operation, according to the company.

Eleven to 14 super-link trucks, which range in capacity up to 30 t, leave the facility each week to destinations in southern and central Africa. In addition, there are two to four container loads shipped to other destinations by sea.

Holtzhausen said: “Our new systems and processes provide management with real-time visibility of demand and stock in all offices across Weir Minerals Africa’s 75 stocking locations. This also gives us end-to-end velocity measurement to monitor the flow of goods from receipt at our warehouse to the actual time of delivery at the customer’s location.”

The same systems are installed at the company’s newly upgraded Kitwe distribution facility in Zambia, streamlining its capacity as a strategic distribution hub for central and east Africa, Weir said.

The benefits for customers of these improvements in supply chain efficiency include reduced lead times and less possibility of stock-outs on customer’s sites, the company said. “This, in turn, gives mines improved availability of equipment, less downtime and higher productivity.”

Holtzhausen concluded: “A significant advantage of optimal supply chain management is that customers gain confidence in our ability to deliver. This means that they can start holding less stock themselves and free up substantial amounts of their working capital.”