APPLY PDS WITH PLANNING AND ENGAGEMENT, URGES BOOYCO

Putting a proximity detection system (PDS) or collision prevention system (CPS) in place in a mining operation is a process that cannot be rushed, says Anton Lourens, CEO of leading PDS and CPS developer Booyco Electronics.

Rather, it needs solid risk assessment, planning, broad engagement and an integrated approach that considers the myriad details involved. Lourens emphasises that for PDS and CPS systems to effectively reduce risk as they are designed to do, everyone must buy into the project and support its outcomes.

“In Booyco Electronics’ many years in this sector, we generally find that haste is counter-productive,” he says. “Where a safety incident has occurred on a mine, for instance, there may be an understandable impatience to get a PDS and CPS solution up and running quickly. The result, however, is seldom what the customer was hoping for, and the process often just takes even longer than it should.”

The key, he highlights, is to conduct a detailed risk assessment upfront to establish exactly what problems the PDS and CPS are expected to resolve. A successful application of this technology will be one in which the mine is proactive about defining the requirement for PDS and CPS, to make sure they meet the specifications identified in the risk assessment.

The next vital task is to involve all stakeholders, including miners at the coal face, various levels of management, the mine training centre, original equipment manufacturers and other relevant suppliers.

“This engagement – and the acceptance of PDS and CPS by these stakeholders – is vital to a successful roll-out,” Lourens says. “Ultimately, all these parties need to understand why they are installing the PDS and CPS equipment, and what the implications and benefits are for each player in the value chain.”

Machine operators are among the key participants in the process, he notes. They need to engage one-on-one with the teams who conduct the equipment installation, and must receive several rounds of training to understand what the equipment will do and how best to look after it.

“A PDS solution is a potentially game-changing safety device that will reduce the risk of collisions and improve workers’ wellbeing in their daily working environment,” he says. “Over the past decade or more, we have seen industry embrace this technology and put it to good use.”

Nonetheless, he points out that the choice of the right PDS or CPS technology to address the identified risk is still a complex and technical process that needs considerable collaboration between suppliers and mines.

SANDVIK’S HARARE POWERHOUSE KEEPS MINING MOVING

With exciting prospects for new mines and brownfield projects in Zimbabwe, Sandvik Mining & Rock Solutions’ Harare-based operation remains at full capacity and at the leading edge of industry innovation.

“We are looking forward to two new platinum operations taking shape, which could be producing within five years, as well as the expansion and digitalisation of existing operations,” says Ian Bagshaw, territory manager for Sandvik Mining & Rock Solutions. “There will also be the rejuvenation of brownfield operations in surface and underground mines.”

Strengthening its capacity to serve its market – which includes customers in Botswana and Mozambique – the company has upgraded the skills, tooling and equipment of its service centre and completed a state-of-the-art technology centre. 

The service centre in Harare remanufactures all current models of Sandvik mobile equipment and also houses  a repair and rebuild facility for all major components as well as a dedicated drifter repair and test centre. 

Its world class Technology Centre works with customers to fully utilise the range of Sandvik digital tools to increase safety and productivity in mining operations.

“We are proud of our strong technical foundation, with about 60% of our 420 plus workforce being engineers, artisans, auto-electricians and other technical specialists,” says Bagshaw. “Investing in training our own people is a priority, and we are proud to note the considerable interest from women in Zimbabwe in pursuing technical careers with some 30% of our apprentices being female at any time.” 

Sandvik Mining & Rock Solutions’ Zimbabwean operation supports the full range of Sandvik equipment in the country ranging from underground trucks and loaders to surface drills and crushing and screening equipment. Bagshaw explains that service and support is tailored to suit each customer’s requirements and ranges from full maintenance contracts to field service callouts, both back by a comprehensive parts stockholding, digital monitoring and ongoing training. 

He highlights the value of the company’s dedicated training department – delivering operator and technical training in-house and for customers. Gap analysis is also provided by the training team, helping mines to assess their skills base and provide targeted training programmes for operators as well as technical and supervisory staff. 

“We are also looking forward to mineral developments in Botswana, where activity on the Kalahari copper belt have created significant opportunities for the mining industry,” he says. “In the near future we will see copper and diamond operations going  underground, which is an exciting prospect.”

Bagshaw notes that Sandvik Mining and Rock Solutions’ Harare facility has remained fully operational through the Covid-19 pandemic, ensuring that mines could continue producing optimally as essential services even during the ‘lockdown’ months.

“We are staying abreast of the latest global sustainability trends and corporate mandates, having installed a 420 panel solar energy system to generate 100 kW of power to our facility,” he says. This supplies about 75% of requirements, and reduces its carbon footprint by over 400 tonnes of carbon dioxide emissions per year.  

PRIORITISE RESPONSIBLE MANUFACTURE, URGES CEMENT LEADER

As South Africa endures some of its most difficult economic times yet, the country should recognise the importance of supporting responsible manufacturing practice in its cement sector. 

The call comes from Hannes Meyer, cementitious executive at leading cement producer AfriSam, who emphasises the strategic value – both economic and social – in a sector that generates this vital commodity. 

“As the backbone of our national infrastructure, cement is also a product that represents our highest aspirations of mineral beneficiation,” says Meyer. “To produce this valuable resource, we must start with mining our own deposits. We then process the ingredients through complex technologies that demand considerable financial investment and expertise.” 

The range of products that result must form part of an intricate supply chain before arriving where it must be used, he says. Almost the entire value chain, however, is local – creating market demand and local job opportunities all along the way. 

“In addition to the basic requirements of the cement business, South Africa’s cement producers are also mineral rights holders who must comply with mining regulations, which includes Social and Labour Plans,” he says. “In addition to normal business legislation, we must go the extra mile to promote development in and around the communities where we operate.”

He points out that this is currently more difficult for cement producers than for miners of more high-value commodities, who are currently benefiting from buoyant prices set by global markets. In contrast, cement prices are determined by demand in the country’s building and construction sectors, where performance remains lacklustre. 

“Despite the challenges, local cement producers like AfriSam continue to meet compliance requirements, as these align with our underlying corporate commitment to the future of Africa and the planet,” says Meyer. 

Added to the industry’s responsibilities, he notes, is the growing pressure on all South African businesses to reduce carbon emissions in the interests of a low-carbon future that responds to the growing dangers of climate change. As an energy-intensive sector, cement production is researching and applying various innovations to reduce its carbon footprint. The government’s recent carbon tax – which is payable by local producers – has created a further imbalance in the market that disadvantages local players, he pointed out. 

“With the wholesale import of cement from countries unencumbered by a carbon tax, there is no level playing field for responsible local manufacturers who are often undercut by imports not governed by our rules,” he says. 

The danger of further weakening the South African base of responsible manufacturers, he says, is that the country will need to rely mainly on its own internal capacity if it wants to generate inclusive and sustainable economic growth into the future. With government hoping to raise infrastructure expenditure, there must be strong local construction expertise and products to implement these projects.

“An important part of local cement producers’ contribution is the skills and technology development that we continue to generate for the South African economy,” says Meyer. “We develop skills in local communities, and opportunities for small black-owned businesses, as well as for women and youth in our supply chain. This is a core pillar of responsible manufacturing that the country should support and reward.”

NEW-GENERATION PLASTICISER USED ON MUSINA BRIDGE PROJECT

An advanced new-generation water reducing plasticiser – CHRYSO® Plast Omega 174 – has notched up another successful application. The product has been used in the concrete mixes for the new Nancefield bridge, which forms part of SANRAL’s Musina Ring Road Project in Limpopo Province. The R640 million project, which allows the N1 to bypass Musina, is due for completion in Q2 2022.

The N1 will pass under the 77 metre long bridge. SANRAL wanted visitors from Zimbabwe and South Africa travelling on the N1 to experience a feeling of being welcomed and the bridge therefore features a prominent pair of 13 metre high ‘hands’ – which are essentially extensions of the centre piers – which express this message. The deck is supported by the columns of the hands and the bridge is aesthetically held on the palms of the hands. 

One of the main reasons CHRYSO Plast Omega 174 plasticiser was selected for the project was that it countered the problem of slump loss.  Due to the available aggregate, ambient temperature and distance from site, CHRYSO Plast Omega 174 was tested and found to be the most suitable admixture. Mix designs were conducted by Matthew Barker, general manager at CHRYSO for technical, mining and export at CHRYSO’s centre of excellence.  

Another challenge was presented by the hot temperatures – up to 45°C – typical of Musina in summer. The concrete temperature needed to be kept under 30°C to prevent thermal cracking. This was achieved by a combination of measures, which included keeping the concrete under shade and cooling it with sprayers, which involved installing a cooling tower to keep the water cool. CHRYSO Plast Omega 174 allowed the mix designs to be optimised, giving more open time on the fresh mix concrete.

CHRYSO Plast Omega 174 was the primary product supplied for the Nancefield bridge and was used for the bridge decks, balustrades and the bridge piers with hands.

Just over 3 000 m3 was required for the concrete of the bridge. The use of CHRYSO admixtures for the mix design was implemented by Jacques Marais, senior plant foreman for the production of concrete at OMV, part of the Raubex Group. The consulting engineers for the project were KBK Engineers.

CHRYSO Southern Africa’s personalised technical service offering and logistics were the deciding factor in OMV using CHRYSO as the main admixture supplier for the project. 

According to Ben Myburg, technical consultant at CHRYSO Southern Africa, “CHRYSO Plast Omega 174 is a multi-dose admixture, which allows concrete to exhibit extended workability characteristics. It improves the cohesion and lowers the viscosity of a concrete mix, which results in an improved homogeneity and compaction, allowing for superior off-shutter finishes thereby eliminating the risk of repairs. By reducing the need for extra water, it increases the durability of concrete by reducing permeability.”

CHRYSO Plast Omega 174 is part of the wider CHRYSO Plast Omega range. Products in the range are ideal for applications such as underwater concrete, pumped concrete, large pours and flowing concrete.

NEW 650 MODEL EXPANDS THE INNOVATIVE CAVEX® 2 HYDROCYCLONE RANGE

When the Cavex® hydrocyclone was introduced to the industry over 20 years ago it set the benchmark for the rest of the market. The recently launched Cavex® 2 took this product range a step further with enhanced performance and design. It marked a new era in separation technology, with its LIG+™ advanced laminar spiral inlet and size of the feed chamber, delivering performance unlike any other cyclone on the market.

Now Weir Minerals has expanded the Cavex® 2 product line with the introduction of the Cavex® 2 650, which addresses the continual demand for increased operational and circuit capacity. It is the second in a range of standard sizes that Weir Minerals is planning to release.

Lerato Ramanala, product manager hydrocyclones at Weir Minerals Africa, says the Cavex® 2 650 hydrocyclone offers excellent separation efficiency and is ideal for both brownfields and greenfields projects, delivering operational flexibility and great recoveries.

She sees major demand for the new 650 model coming from customers with high throughput plants that require coarser cut points, a requirement typically found in gold, platinum and copper applications.

She adds that the new 650 model hydrocyclone – like the other sizes in the Cavex® 2 range – can easily be retrofitted at existing sites, replacing either the original Cavex® or competitor cyclones. “This allows increased throughput while using the same footprint, and customers are very enthusiastic about this feature,” she says. 

It is important to note that enhancements of the hydrocyclone performance go hand in hand with improving the environmental footprint of the equipment. 

By reducing bypass returning to the mill, fewer fines are returned to the mill in a closed-circuit milling process, thus reducing the need for energy to be used to further process particles that are already small enough to move on to the next stage. 

As a hydrocyclone that can make a finer separation, the Cavex® 2 650 model can operate at a lower pressure for further energy savings or a higher feed density for water savings while maintaining the existing cut size from the hydrocyclone. 

The Cavex® 2 650 hydrocyclone delivers significant benefits to mining customers including an increase in operational and circuit capacity of up to 30%. It can be equipped with Synertrex®-enabled monitoring system which can detect roping or blockage conditions in advance for continuous, efficient operation of the hydrocyclone.

WEST AFRICA OPPORTUNITY FOR PIONEERING CEMENT TECHNOLOGY

The cement sector in West Africa could make exciting use of clay calcination technology to reduce carbon emissions and energy consumption in cement production, in line with the industry’s sustainability goals. 

As a leader in clay calcination, FLSmidth offers its technology to replace a portion of clinker with environmentally friendly calcined clay, thereby cutting carbon dioxide emissions in comparison conventional cement production. 

According to Deon de Kock, FLSmidth President for Sub-Saharan Africa, Middle East and South Asia, clay calcination is one of three main areas of technology advancement in cement that the company is currently pursuing. In terms of the company’s MissionZero pledge, it is committed to enable FLSmidth customers to run cement production at zero emissions by the year 2030.

“In addition to clay calcination, we are also focused on enabling the replacement of fossil fuels with alternative fuel sources, and on enhancing carbon capture in cement plants,” says De Kock. “Our current involvement in Europe’s first full-scale clay calcination installation has raised interest globally, and we look forward to applying this technology in our Africa, Middle East and South Asian region.”

The cement sector has had a difficult few years, says De Kock, having to deal with a challenging economic climate while under pressure to meet ever-more stringent environmental regulations and expectations. 

Sridhar Shanmugha Sundaram, FLSmidth Vice President for Cement in Sub-Saharan Africa, Middle East and South Africa highlights that FLSmidth’s new flash calciner system can produce a highly reactive clay that increases the clinker substitution by up to 40% in the final product.

“Addressing the bottom-line issue, this solution also brings energy savings as calcined clay activates at a much lower temperature than clinker – with required temperatures of 750 to 850˚C instead of 1400 to 1500˚C,” Shanmugha Sundaram he says. “This means lower costs to generate the necessary power.”

He notes the process can deliver significant fuel and power savings of 30% and 40% respectively, when comparing the operating cost of making a tonne of clay versus a tonne of clinker. While a traditional ‘ordinary Portland cement’ (OPC) contains 95% clinker and 5% gypsum, ‘green’ cement can contain as little as 50% clinker – with 30% activated clay, 15% limestone and 5% gypsum. This has a dramatic impact on the plant’s carbon footprint, reducing CO₂ emissions per tonne of cement by 40%.

In addition to FLSmidth’s strong presence in South Africa is its Ghana office – a 13-strong team of local people which is committed to developing local expertise and capacity in the West African region. According to Joseph Appiah-Kubi, General Manager of FLSmidth in Ghana, the company’s corporate social responsibility programme includes a graduate scheme to empower Ghanaians, transfer skills and provide opportunities in the economy to young graduates. 

“This year we have had our first cohort of graduates working with us as part of the government’s compulsory National Service Scheme,” he says. “We will also soon be receiving our first cohort of graduate trainees – those who have finished one year at service engineering school and are coming to us to learn. This gives young people vital experience in the workplace to improve their employability in the market.”

MERITS OF MECHANICAL AND DIGITAL OPTIONS IN DOSING PUMPS

Dosing pumps play an important role in many industries from mining and wastewater treatment to pharmaceuticals and food production – and are available in a growing range of mechanical and digital options.

“Choosing the right pump starts with understanding the respective areas where mechanical and digital dosing pumps excel,” says Tshephang Sithole, sales engineer – water treatment at global pump specialist Grundfos. “While high flows and high pressures might be prioritised in some applications, for instance, other users need to focus on accuracy or remote-control functionality.”

Sithole points out that many industrial applications such as water treatment plants or mining will tend to need a robust solution that delivers large volumes of water at pressures of up to 150 bar. There are still certain automatic functions, though, depending on the configuration. 

“While Grundfos’s basic range of mechanical dosing pumps requires an operator for most functions, our analogue relay (AR) range has additional features such as an automatic stop when the chemicals are depleted,” he says. “Furthermore, the D-range has servomotors to automatically set the stroke length, thereby adjusting the dosing flow.”

This is done with a 4-20 mA signal that can be remotely transmitted from a SCADA system or other digital input. Variable speed drives (VSDs) can also be fitted to these pumps, and the frequency can be adjusted up or down to vary the dose.

Digital dosing pumps, by contrast, come with a range of features that make them most suitable for automated plants or where higher levels of monitoring and control are required, including remote functions. Grundfos has been a pioneer of digital dosing for over 20 years.  

“Automation functions are particularly valuable for companies who have plants in different parts of the country,” he says. “If loadshedding leads a pump to trip, for instance, an alarm will notify the user, and they can remotely reset and restart the operation.”

They are also preferred where accuracy of dosing quantities is prioritised, or where dosing volumes are very small. Some digital dosing pumps boast high turn-down ratios as low as 1:3,000, and can deliver pressures of down to 0,002 bar. 

“They can even pick up leaks in the line, and will help prevent liquid losses by automatically alerting the operator,” he says. 

The automatic de-aeration function is another valuable element in advanced digital dosing pumps, allowing them to detect and remove bubbles from a line. This is important as bubbles will impair the accuracy of dosing. 

NEW IRON ORE MINE ADDED TO KWATANI’S N CAPE FOOTPRINT

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 greenfields expansion of 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,” says Jan Schoepflin, Kwatani’s general manager: sales and service. “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.”

Kwatani’s scope of work on the 700 tonne-per-hour dry processing plant includes a1,5 metre wide grizzly screen to remove fines from the run-of-mine material before it reports to secondary crushing and a 1.5 metre single deck scalping screen. The company will also install two 2,4 metre 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,” says Mabotja. “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. With 47 years in the vibrating screen and feeder business, the company can bring its myriad lessons in the field to bear on each project. 

“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 says. “The customer was also able to visit our 17,000 square metre local manufacturing operation in Kempton Park regularly to see how we work, to check on fabrication progress and to witness the testing process.”

This level of engagement with customers builds their confidence in Kwatani’s ability, as they can experience first-hand the systematic, quality-controlled approach to design and manufacturing. The company’s extensive facility is ISO 9001:2015 certified. 

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

“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,” says Mabotja. “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. 

LOCALLY BUILT DIESEL PUMPS FOR EVERY APPLICATION

With its expertise and experience in custom-building diesel driven pumps locally, Integrated Pump Rental ensures their customers get exactly what they need with a short lead time.

“Our in-house capability allows us to design and build pumps to any required specification,” says Steve du Toit, rental development manager at Integrated Pump Rental. “Part of our process is to assess the application and discuss options with the customer, advising on a solution that suits both the operational requirement as well as their budget.”

As the local distributor of the high quality Sykes diesel driven  pump range, Integrated Pump Rental generally uses the appropriate Sykes wet end for each pump design, usually coupled to a Kirloskar diesel engine – a well-respected and popular brand. However, the brands of key components can be chosen by the customer according to their preference, says Du Toit.

“We then design and construct the fuel tank and base or trailer unit, the scale of which depends on the pump’s intended working conditions, mobility and fuel consumption,” he says. “The material of construction must also be carefully selected, based on factors like water acidity and abrasiveness.”

In the case of high acidity, for instance, stainless steel is the preferred material, while more abrasive applications can be served with a coated S.G. iron material. The solution is put together by a team that includes qualified draughtsmen and experienced boilermakers, electricians and diesel mechanics. 

“Our performance driven approach ensures that all the necessary specialists collaborate closely in turning the customer’s requirement into reality,” he says. “This includes hands-on involvement by top management, making for quick decisions, innovative solutions and a fast process all round.”

The result is a top quality locally assembled pump which draws on readily available components and can be delivered within tight timeframes. Customers can also rely on Integrated Pump Rental’s well-known service levels to ensure ongoing maintenance and optimal uptime. 

“Our versatile team, combined with the wide range of Sykes pump capacities, allows us to locally build pumps for every application – from small-scale contract dewatering to large open pits on mines,” he says. 

Du Toit notes that many of their custom-built pumps are for customers who have previously rented pumps from the company, and are impressed by the performance and reliability of those Sykes units. While diesel driven pumps are most in demand, Integrated Pump Rentals can also design pumps with electric motors, for those applications where electrical power is available on site. 

TOP AWARD FOR MULTOTEC’S EXPORT EXCELLENCE

In the face of worldwide logistical and supply chain challenges, leading South African minerals processing original equipment manufacturer (OEM) Multotec has had a stellar export year – emerging as a co-winner in the large business category of the 2021 Exporter of the Year Awards last month.

Hosted by the South African Capital Equipment Export Council (SACEEC), the awards recognise exceptional achievement by manufacturers in the capital equipment sector in terms of value, volumes and export destinations.

“As a proud South African OEM for almost 50 years, we greatly appreciate this recognition, especially given the local and global headwinds that all businesses are currently facing,” says Jaco du Toit, managing director of Multotec International. “Local operational challenges include unreliable power supply and incidents of labour unrest in the country, while international logistical capacity remains severely disrupted by the Covid-19 pandemic.”

Lead times in some transportation segments such as ocean freight (port-to-port) have increased by around 35% while costs have doubled. Du Toit notes that Multotec has overcome these challenges and met their export targets for the year – continuing the journey of growing the group’s international presence. 

Having initiated its internationalisation strategy some 20 years ago, Multotec now earns about 55% of its revenues from exports. With about half of these exports going into sub-Saharan African countries, the group is also active in Europe, the Americas, Australia, China and the Commonwealth of Independent States (CIS), especially Russia, Belarus and Ukraine.

“The key to our success in exports has been our ability to maintain productivity and stability of our manufacturing operations, which embrace 60% local content,” he emphasises. “We have never deviated from our commitment to building our economy through innovation and expertise; we believe fundamentally in the power of local business to transform our country for the better.”

Multotec employs about 1,9000 people at its various sites around Spartan and elsewhere, and supports a large range of local suppliers and subcontractors in generating its wide product offering. It also invests heavily in skills development and SED projects. He explains Multotec’s export strategy is speed to market by as getting closer to customers wherever they are based, plus its ability to deliver a quality product on time at a competitive prices anywhere in the world.

“Underpinning our export success has therefore been our global network of strategically located subsidiaries in certain countries, supported by agents in others,” says Du Toit. “In Africa north of South Africa, for instance, we have companies in Botswana, Mozambique, Zambia and Ghana with strategic partners in Namibia, Zimbabwe, Democratic Republic of Congo, Guinea, Sierra Leone and Mauritania.”

This allows not only the export of equipment but facilitates an ongoing field service maintenance relationship and after-sales service to ensure the technology continues to add value on customer sites. The same approach has been applied in Canada through Multotec Canada, with about 60% of the supply line into that country being sourced from South Africa. The 14,300 m2 Spartan facilities also manufacture most of Multotec’s equipment supplied to Australia, Europe and the CIS.

“Having weathered a difficult couple of years since the outbreak of the pandemic, we have succeeded in our aim of not shedding any jobs,” he says. “As the mining sector surges ahead, we are now reaping the rewards of that achievement. At Multotec, we aspire to grow a truly South African brand to become a respected name in all mining sectors in the world.”