SYKES PUMPS ARE THE SOLUTION FOR MINE DEWATERING IN AFRICA

Two Sykes XH150 trailer mounted pumps will soon be doing dewatering duty at a mine in Africa, supplied by southern African distributors Integrated Pump Rental based in Jet Park, Gauteng.

This range of diesel powered units is ideal for dewatering an open pit, offering characteristics that include high head and head flow, according to Lee Vine, managing director of Integrated Pump Rental.

Vine emphasises that even the best run mine sites can be plagued by expensive challenges if they do not effectively control groundwater ingress into the open pit.

“This can cause not only programme delays but could also adversely affect health and safety on site,” he says. “So, when addressing the need for dewatering, it is vital that contractors deal with a supplier that understands dewatering applications and is able to provide the correct level of technical assistance; this will ensure that the most efficient methods are selected for the demands of a specific site.”

The Sykes Xtra High Head pump set boasts automatic priming and solids handling, so it dewaters more efficiently and effectively; it also has one of the best shaft stiffness ratios of any automatic priming pump on the market.

“These are fully automatic priming pumps and can run dry for extended periods due to the oil bath mechanical seal assembly,” he adds. “The low fuel consumption makes them cost effective to use for extended periods for time when dewatering.”

The pumps – designed for robust and reliable performance with high volumes of water – have an established reputation for the fast and effective control and removal of sub-surface water, he says. They can be primed with long suction hoses and can manage suction lifts of up to nine metres.

The pumps can even operate in ‘snore’ condition, which accommodates fluctuating suction levels; the pump will snore until the liquid is available for the pump to fully reprime itself automatically.

APEX’S SMART RESET DOOR FOR SAFE, PRODUCTIVE WORKSPACE

Helping warehouses, plants and shipment areas to raise turnaround times and safety levels while reducing downtime is the innovative Smart Reset roll-up door from industry leader Apex Strip Curtains & Doors.

This heavy duty door is equipped with an integral electronic safety device that automatically reverses its motion if an obstacle is encountered when the door is closing. Also, the bottom passive edge of the Apex Smart Reset Door is made of flexible and shock-proof material, protecting the door itself from damage – while two photocells mounted inside the casing of the door augments the electronic system to ensure that the curtain rolls uniformly.

Downtime is kept to a minimum with features such as the door’s automatic ‘fix’ characteristic. While the nature of the operations conducted through roll-up doors makes the sides vulnerable to being dislodged, this design allows it to recover automatically with a simple opening and closing operation.

If the door is inadvertently hit by a vehicle or object passing through, the hinges will come off the guides since the side hinges on the door slide along special guides, together with the flexible curtain ends. This avoids damage to the flexible curtain itself.

The Apex Smart Reset Door is also well equipped to deal with power failures and malfunctions. Fitted with a release lever, it can be opened from either side. It can be activated by any type of remote control equipment, including photocells, pressure-sensitive mats, movement detectors or induction loops – as it is controlled by an electronic unit that complies with all IEC regulations.

Its unobtrusive design makes it ideal for openings of up to two metres high and four metres wide, and it can be equipped with an optional inverter system to make it easy to adjust its opening and closing speeds. To reduce stress on mechanical components and improve the door’s reliability and longevity, there are soft-start and soft-stop features.

Equally strong and durable is the curtain itself; manufactured in Class 2 self-extinguishing polyester, it can withstand winds of up to 120 km/h. The panel sections are interchangeable and connected by extruded aluminium profiles which reinforce the entire door – further reducing maintenance requirements.

SUSTAINABLE PRODUCTIVITY IMPROVEMENTS THROUGH QUALITY MAINTENANCE

Choosing an appropriate maintenance package from an original equipment manufacturer is a key step in the journey towards sustainable productivity enhancements.

According to Willie van Wyk, general manager at FLSmidth, the company’s range of Krebs slurry pumps come with a range of maintenance options that drive productivity and reduce plant downtime.

“Pump audits are important, as these create benchmarks for improvement programmes, using indices like inlet and discharge pressure, flow rate and solids concentration to indicate problem areas and measure performance improvements,” he says. “Condition monitoring also helps avoid unscheduled maintenance, and includes the systematic documenting of vibrations and recording of pump maintenance activities.”

Van Wyk says this approach also can reduce power consumed by pumps, and achieve longer lifespan for gland seals and bearings. As part of the maintenance programme, he highlights the features of the Krebs millMAX™ slurry pump range which allows fine-tuning while the units are still running thereby enhancing productivity.

“These adjustments to the millMAX™ range of pumps, for heavy duty output and abrasive slurries, are done on the suction side sealing through an adjustable wear ring. This avoids any recirculation and grinding of slurry which could lead to power loss,” he says. “This fine-tuning means that the pump does not have to speed up to maintain higher levels of production. By closing the gap between the impeller and suction liner, the flow and head stays constant in the pump.”

By remaining operational through the fine-tuning process, plant stoppages are avoided so efficiency and throughput can continuously be optimised. Van Wyk emphasises the value of performance-based pump maintenance and servicing agreements, which contain specific measures to document results.

“In implementing these agreements, customers have access to the expertise of FLSmidth’s Pump Technical Group, who bring their experience in a vast range of applications around the world,” he says.

FLSmidth’s focus on lifecycle cost aims to improve pump performance and cut operating costs. Essentially, choosing the right maintenance package will lower the total cost of ownership of vital pumping equipment.

MULTOTEC TO PROVIDE CONTINUOUS ION EXCHANGE EQUIPMENT TO DRC CUSTOMER

Leading mineral process company, Multotec Process Equipment, will be providing a continuous ion exchange (Clean-iX®) metals processing scavenging equipment to a customer in the Democratic Republic of Congo.

The equipment, using Clean-iX® ion exchange technology from Melbourne-based metals recovery and industrial water treatment specialists Clean TeQ, will treat up to 20 million litres a day of a raffinate stream, removing contaminant metals and improving the quality and environmental rank of the raffinate before it is processed further.

The technology is built on the foundations of batch ion exchange, a process that has been used in the industry for over 50 years. The Clean-iX® process allows the extraction of metals from clarified leach liquors using a ‘moving packed bed’ column, maximising adsorption; this method of extraction has higher efficiency than conventional technologies.

As a leading provider of high-quality mineral processing equipment and solutions to the mining, mineral processing, petrochemical and power generation industries, Multotec has an exclusive technology distribution agreement with Clean TeQ for the African continent.

Carien Spagnuolo, senior process engineer at Multotec Process Equipment, says the group leverages its extensive sales and service network in African countries to bring customers leading edge technologies from around the world, especially for niche applications or difficult to treat waters.

“The DRC contract confirms the rapidly increasing global interest in the application of continuous ion exchange technology for metallurgical scavenging and water purification,” she says. “The installation is expected to offer another valuable reference for the efficacy and cost effectiveness of the process, for which there is a large potential market.”

In metals recovery and purification, Multotec is able to draw on Clean TeQ’s Clean-iX® technology. There is also a suite of water purification technology from Clean TeQ that includes Continuous Ionic Filtration (CIF®), DeSALx® for desalination and sulphate reduction, and HiROx® for high recovery reverse osmosis.

The DRC project is the second contract awarded in the past 12 months in which Multotec has applied Clean TeQ’s technology offering. Multotec is also currently implementing a proprietary continuous ionic filtration wastewater treatment solution at a mineral processing plant in the Middle East. Multotec was the principal bidder with overall responsibility for delivering the complex wastewater management and effluent treatment systems for the pyro-metallurgical mineral processing facility.

M&C ZAMBIA NOW OFFERS IN-HOUSE 12 DYNAMIC TON BALANCING SERVICE

The largest balancing machine in Zambia was recently successfully commissioned at Marthinusen & Coutts’ Zambian operation in Kitwe. The fully upgraded 12 ton Schenck machine is capable of balancing rotors up to 12 tons at operating speeds up to 3300 r/min, 5.5 metre in length and with diameters of up to 2.2 metres.

Careful planning and execution by Marthinusen & Coutts, a division of ACTOM, ensured that the machine was successfully installed, calibrated and commissioned. The local M&C team received training to ensure optimum operation of the machine.

The in-house ability to precision balance rotors to very high accuracy is a valuable service to customers in the region, and it will no longer be necessary to transport large components across border to South Africa for this work to be done. This local dynamic balancing service also expedites the repair process, reducing delivery time, and avoiding the risks associated with long distance transportation. All this translates into a bottom line cost reduction for customers because of the quicker turnaround times.

The service will prove to be invaluable to customers and OEM’s operating in the Copperbelt region, and underpins Marthinusen & Coutts Zambia’s position as the leading electro-mechanical repair facility in the region.

Over a period of four years Marthinusen & Coutts Zambia has successfully upgraded its test facilities which can now accommodate both AC and DC motors. The facility also boasts a temperature-controlled burnout oven, curing ovens and vacuum pressure impregnation (VPI) tank. Furthermore, winding verification ensures that stators and rotors are wound to international and OEM specifications. Further upgrades have also been implemented to the mechanical repair shop, which also offers machining, milling and submerged arc welding.

KWATANI SCREENS FOR ELIKHULU RETREATMENT PLANT

Engineering group DRA has ordered six large screens from Kwatani for the R1,6 billion Elikhulu gold tailings retreatment plant facility at Pan African Resources’ Evander operation in Mpumalanga.

“Kwatani was involved from an early stage in this project, so we were able to custom design this equipment at the study phase, allowing the EPC to readily integrate the design into the plant design,” says Kwatani CEO Kim Schoepflin. “Our focus here was to deliver a cost effective, fit-for-purpose solution to the customer that is technically appropriate to their needs; which is to retreat 1 million tonnes per month of gold tailings.”

Cognisant of the price pressures on all stakeholders, Kwatani was able to hold the price from the original quote date through to final agreement. Making the customer’s purchasing decision easier was also Kwatani’s substantial reference base in the gold sector, as well as at the Evander operations.

“We also helped the EPC with designs for ancillary equipment, assisting in holding down costs for the overall plant structure,” says Schoepflin.

Four of the six screens – the two trash screens and two carbon safety screens – are in excess of three metres wide, feeding 1,500 tonnes per hour. The remaining units comprise one regenerated carbon screen and one loaded carbon screen, through which some 2,000 m3 of slurry will pass per hour.

“We designed these six large screens to facilitate a commonality of spares in the plant, so that parts will be easily interchangeable. This will reduce the necessity for a holding a large inventory of these items,” she says.

She emphasised the low margins inherent to gold retreatment operations, highlighting the importance of reliability in the way that Kwatani equipment is designed, tested and maintained.

“Uptime of the plant is a key factor in sustaining a profitable operation in this sector, so we place high priority on both the process duty that our units must achieve and their mechanical durability to achieve low cost of ownership over their life-times,” she says.

TRAFO FAST TRACKS DRY-TYPE TRANSFORMERS FOR BISIE IN DRC

Alphamin Resources’ remote Bisie tin mine is being supplied with fit-for-purpose dry-type transformers by Johannesburg-based Trafo Power Solutions, in a fast track project that will see the complete solution manufactured in just 12 weeks.

Bisie’s location – some 160 km north-east of Goma in the Democratic Republic of Congo’s North Kivu province – places constraints on the transformers’ installation that have been taken into account in their careful selection and design.

“With a very difficult access road to the mining operation, the substation and transformers have been custom designed to withstand the many stresses expected during transport,” says Trafo Power Solutions managing director David Claassen. “To deal with the extreme heat and humidity of over 90%, we have also designed the ventilation and airflow in-house.”

The delivery will involve the movement of two 3000 kVA, 400 V / 11 kV cast resin transformers housed in six metre high cube containers. The consignment will also include the ventilation systems, lighting and small power equipment. These transformers will be used for stepping up the supply from a diesel powered generator plant – from 400 V to 11 kV – to feed the mine.

Project scope also includes two 100 kVA, 400 V / 400 V Dyn11 dry-type lighting transformers for application outdoors.

“The design of these dry-type transformers makes them suitable for the climatic conditions at the mine,” says Claassen. “They require only a minimal movement of air across the windings to cool them down, although forced air options can also be employed where necessary if ambient temperatures rise high enough.”

The higher efficiency of the cast resin design means that heat losses are lower, along with cooling requirements. This efficiency also reduces the energy consumed by these transformers, and hence will reduce diesel consumption in this application.

“An important advantage in this remote location is that dry-type transformers are almost maintenance-free and could last for 25 years without significant attention,” he says. “Oil-filled transformers require regular maintenance including oil sample analysis to ensure operational consistency and safety.”

With no oil required as a coolant, the dry-type transformer is simple, safe and installable indoors without the need for its own civils infrastructure such as bund walls and structures to ensure safety and environmental protection.

“Trafo Power Solutions works with customers to engineer technically appropriate and proven solutions for their applications,” says Claassen. “The fact that we can design and manufacture within this project’s tight deadline is further evidence of our flexibility and ability to meet demanding schedules.”

PARTNERSHIPS KEY AS SA TACKLES WORLD-CLASS GAMSBERG ZINC PROJECT

At Vedanta Resources’ Gamsberg mine in the Northern Cape, Zest WEG Group is working closely with lead contractor ELB Engineering Services as a preferred supplier to standardise on its range of transformers and motors across a number of on-site applications.

The Gamsberg project is South Africa’s largest current greenfields mining project, and will exploit one of the world’s largest zinc deposits. It is being developed at a capital cost of US$400 million and is expected to produce 250,000 tonnes a year of zinc metal in concentrate.

“This is a very exciting project for South Africa, especially as we haven’t seen a new mine being developed in the country for many years,” says Dr Stephen Meijers, chief executive at ELB Engineering Services. “Vedanta Resources has shown real intent in terms of investment in South Africa; not only in this project but in others, and we are proud to be building Gamsberg.”

ELB Engineering Services’ first package of work was the provision of water from the Orange River to the process plant, through an upgraded pump station and a pipeline of about 40 kilometres. The second package is the supply of power from the existing Eskom switching yard via overhead lines to the mine, and the third is the process plant itself covering all aspects from run-of-mine tip through to final product, including process dams and balance of plant.

“First product is expected through the plant by the middle of 2018, with the civil works being largely completed by the end of the second quarter of 2017,” says Dr Meijers. “Structural and mechanical construction on the plant is now starting to become the focus of work, and the pace will continue to be intense until middle of 2018.”

Extreme temperatures on site – down to minus 10 degrees Celsius at night in winter and up to between 45 and 50 degrees in summer during the day – have affected the design and the construction methodology, he says. This has meant making optimal use of the cooler hours in summer, even pre-manufacturing as much as possible at night before placing during daylight hours.

Dr Meijers is a strong believer in partnerships, with much of the project technology being applied through exclusive partnerships with preferred suppliers.

“We’ve worked with Zest WEG Group for many years, and appreciate their professionalism, quality of service and reliable scheduling,” he says. “We have therefore placed a number of the contracts for this important and fast track venture through Zest WEG Group companies.”

As a group of specialist electrical companies, Zest WEG Group’s scope of supply covers two main spheres – the water-related package which focuses on the upgrading of the municipal supply station providing water to the Gamsberg site, and the package for the mine’s zinc concentration plant and related processes.

In this process, Zest WEG Group supplied a number of non-standard products – providing the mechanical and design engineering necessary to ensure that the non-standard specifications could be met, including the redundancy requirements to ensure optimal plant uptime.

“The Gamsberg plant is a showcase for WEG motors and includes four different MV motor ranges that were fit-for-purpose in their different applications,” says Kirk Moss, manager – medium voltage business at Zest WEG Group company Shaw Controls. “These included our new W50 line, the HGF line, large slip-ring motors from our M line, and our W22 line of low voltage IE3 motors; meeting the range of requirements demonstrated Zest WEG Group’s versatility in terms of the multiple MV and LV motor offering.”

Various pole mount and distribution transformers, ranging from 500 kVA to 2 500 kVA, being prepared for transportation to the Gamsberg Project site.

Energy efficiency is a key driver in the project design, with high efficiency W22 WEG IE3 motors being specified across the site. To streamline and facilitate the implementation of this focus, Zest WEG Group was tasked by ELB Engineering Services to coordinate with all the original equipment manufacturers that would use motors to drive their equipment. This is to ensure that the principle of energy efficiency is fully applied across all aspects of the project scope.

“Importantly, we are supplying all the LV motors for the plant, ensuring the project will save considerably on its energy cost by complying with the IE3 energy efficiency standard,” says Moss. “These motor are also IP66 rated with Class H insulation, which enhances the IE3 specification by providing higher ingress protection and accommodating a higher temperature rise.”

The WEG Transformers Africa facility where the various transformers for the project were manufactured.

According to Shaw Controls business development manager Tyrone Willemse, the MV Mill package being supplied for the plant comprise two large 6,5 MW WEG motors – MAF 11 kV slip ring units –specified for the ball and semi-autogenous (SAG) mills.

“The jaw crushers will be fitted with proven, robust 11 kV 400 kW motors from WEG’s HGF line,” says Willemse. “We were also requested to supply the distribution transformers on the plant.

Zest WEG Group’s contribution to the upgrading of the water supply facility involved the provision of eight 3,3 kV 550 kW medium voltage (MV) motors as well as its locally designed and manufactured transformers to provide power to the pump stations.

“This included two 2,5 MVA transformers (reducing 11 kV down to 3,3 kV), as well as four 315 KVA (3,3 kV down to 400 V) units,” says Willemse. “Once again, these were not standard transformer designs but were prepared specifically to suit the specifications of the client.”

The package also includes the new WEG W50 motor, which features a compact size and design; through the application of the latest computational analysis techniques, both the scale and the cooling efficiency have been improved – delivering optimised airflow that enhances the unit’s expected lifespan.

“This means that the performance and temperature rise of these motors is not compromised in any way by its smaller dimensions,” says Moss.

Connected to these motors are WEG MVW01 3,3 kV variable speed drives (VSDs), further enhancing energy efficiencies. These are also compact – just 2,315 mm high, 2,600 mm wide and 980 mm deep including the integral phase-shift transformer – together helping reduce the footprint of the substation.

The Variable Speed Drives (VSDs) also boast a low component count – imperative in terms of reliability – of just three power arms that can be changed in two or three minutes, allowing for quick maintenance and low downtime in the case of replacement.

“Helping to meet the short lead-times demanded in this project, Zest WEG Group was able to leverage the global WEG group’s multiple manufacturing facilities around the world, giving us flexibility in terms of where we build and how quickly we can source product,” says Moss.

Willemse adds that an important aspect of the group’s added value has been its five year guarantee covering the hundreds of LV motors on the project.

BOOYCO BRINGS NEW TECHNOLOGY TO FIRE SUPPRESSION MARKET

Building on its established reputation in proximity detection systems (PDS), Booyco Electronics is now also offering the latest fire suppression technologies to help customers manage their health and safety risk.

“It was a natural extension of our business to move into fire suppression,” says Anton Lourens, managing director of Booyco Electronics. “As experts in PDS detection, our equipment is vital in detecting potential dangers around TMM’s. Now we can also offer the latest suppression systems as part of the total solution from a single service provider thereby creating a better value proposition.”

Lourens emphasises that the effectiveness of fire detection and suppression systems is becoming a more urgent issue for mines as there are new SANS standards being formulated for fire detection and suppression systems on heavy duty mining machines.

He says the company will be the preferred distributor for Advanced Automation Systems (AAS), the company which exclusively markets the DAFO brand of vehicle fire protection and FirePro aerosol-based extinguishing systems in South Africa.

“We believe that AAS is a market leader in multiple offerings that hold great value for our existing customer base in the mining and related industrial sectors,” says Lourens. “Our long established geographical footprint, sound reputation and strong relationships in the market will, in turn, offer great opportunities for AAS to grow its impact.”

He highlights the technological advances built into these products, emphasising that mines are more than ever needing to embrace new technologies for more effective technical and bottom line performance. The DAFO products – a world-renowned brand based in Sweden – include a wet chemical-based system that is engineered to inhibit the chemical reaction of the fire while extensively cooling the hot surface and finally creating a film forming to prevent further re-ignition.

“This is an important step forward from existing dry chemical powder-based fire suppression systems, which either extinguish the fire by suffocation or by chemical inhibition but do not address the issue of cooling,” he says. “Cooling is vital if the fire is to be completely extinguished and for no possibility of re-ignition to exist.”

He says the use of wet chemical rather than dry chemical powder also reduces the maintenance requirements, as it is not affected by the vibration of the machine and is non-corrosive, non-toxic, environmentally friendly and water soluble. The system can be used on load-haul dumpers, utility vehicles and other underground machinery, as well as surface shovels and haulers. It is also suitable for conveyors and other materials handling equipment.

FirePro Systems is also a global brand, with installations in over 110 countries, and is a leader in condensed aerosol fire extinguishing technology. In contrast to traditional methods, FirePro aerosol extinguishes fire by inhibiting the chemical chain reactions present in combustion on a molecular level – removing the flame free radicals and extinguishing fire without depleting oxygen. The aerosol is stored as a solid and under no pressure which gives the product an extended life span with virtually no maintenance requirements. The FirePro products are non-corrosive, non-conductive, non-toxic and environmentally friendly.

These systems can therefore protect enclosures of any volumetric size, from less than a cubic metre to thousands of cubic metres. This makes them suitable for equipment such as motor control centres, electrical panels, substations, mini-substations, e-houses and electrical mining skids.

A typical system layout for a DAFO fire protection system.

“Both the DAFO and FirePro offerings come with environmental advantages, which will be required by the new standards on fire suppression,” says Lourens. “The standards will also include a performance test, to ensure that technology being offered is fit-for-purpose and reliable before it can be approved.”

He concludes that Booyco Electronics will be putting its weight behind these systems because they are proven and will ensure optimal reliability; the company also ensures that its strong support network of skilled personnel is in place to implement and maintain these solutions.

FirePro products extinguish fire by inhibiting the chemical chain reactions.

ENGINEERED TRANSFER CHUTES SAVE COSTS

The uncontrolled discharge of bulk materials through conventional chutes is associated with escalated maintenance and replacement costs. By custom designing and engineering transfer points, productivity is enhanced and costs are reduced. A number of blue chip customers around the globe have adopted Weba Chute Systems to increase efficiencies and decrease downtime.

Mark Baller, managing director of Weba Chute Systems, says that optimised plant design should consider each element within the process flow. “Globally, companies accept that best practice includes the incorporation of transfer chutes that have been designed and engineered to suit the specific application. Unfortunately, many project houses do not afford transfer chutes the same importance as a screen, grizzly, crusher or feeder.

“Another area that needs clarification is the erroneous belief that mines can reduce capital costs by installing a cheaply fabricated chute. Ironically, these poorly constructed chutes incur unnecessary operational costs for the customer. The global mining community acknowledges that poor design and implementation of transfer points can result in increased maintenance costs for minerals processing systems. This fact belies the belief that chutes are just fabricated platework,” adds Baller.

“If due consideration is given to customisation at the design phase the customer will benefit from reduced maintenance requirements, improved transfer conditions, longer conveyor belt life and higher throughput. In addition, the Weba Chute Systems are designed in such a way that they minimise impact that traditionally sends clouds of dust into the air. This boosts occupational health and safety compliance,” Baller continues.

The Weba Chute Systems team of engineers has extensive experience in the field and a wealth of intellectual property. “Each project is approached on an individual basis, with engineers adopting a hands-on approach. Liaison with customers during the design phase allows us to devise tailor made solutions that provide a high-level return on investment,” says Baller.

“Unfortunately, when a poorly designed or conventional transfer chute fails we are forced to go in after the fact and redesign and re-engineer, not only the chutework but often we also have to reconfigure the entire transfer point. If the systems were correctly designed and engineered from the outset, then these issues would not arise,” adds Baller.

The Weba Chute Systems team utilises Discrete Element Modeling (DEM) simulations as a verification tool only. “Design ideas and concepts should be derived from the intellectual property that exists in our engineering team. By complementing our own sound engineering tools and substantial practical knowledge with DEM, we are able to provide customers with a high-end transfer chute solution.

“We are not competing with the project houses. It is not a draughtsman’s job to design chutes. These products require custom engineering to ensure that the transfer point solution precisely meets the specific parameters within a given application. Customer satisfaction can be measured in improved material flow, minimal maintenance and a substantial saving on costs,” Baller concludes.