INCREASED CALL FOR SLURRYSUCKER TO DESILT

Increasing pressure to lower the total cost of ownership (TCO) has seen many mining operations review their water management strategies. Integrated Pump Rental reports that this has led to increased enquiries about its locally manufactured solutions that mitigate the challenges of silted process water ponds.

Ruaan Venter, development manager at Integrated Pump Rental, says there is now a more proactive stance being taken on the monitoring of these water reservoirs.

He says this is most encouraging as Integrated Pump Rental has been calling for a more systematic approach to the monitoring of process ponds. “Apart from the fact that South Africa is a water scarce country, we have always maintained that the proactive monitoring and regular desilting of process water ponds will save customers in the long run.”

Adding to that challenge of water shortages is the need for mining operations to reduce their reliance on municipal water supplies. This means that efficient monitoring of process water ponds is critical in terms of recycling and reuse of water for the plant and other purposes on a mine.

Ongoing monitoring of process water ponds will facilitate desilting activities on a rotational basis. This will eliminate the disruption of unexpectedly having a pond out of service.

Venter adds that the economic value of the minerals in the silt should also not be forgotten and this material can be pumped back into the plant for reprocessing. The value claimed from retreating the silt can, in many instances, pay for the pond cleaning activity.

“Taking this concept one step further, we have found that mines are investing in their own SlurrySucker equipment,” Venter says.

The SlurrySucker is was developed by Integrated Pump Rental for applications where the water retention and water holding capacity of process ponds in threatened. It is also ideal for the dredging and cleaning of water capture areas where silt or slimes has become an issue.

This innovative dredge unit needs only a 400 draught of water above the sediment for the floating unit to operate. A dewatering pump takes the top layer of water and feeds it down to the dredge-head, where the slurry is agitated so it can be pumped out.

“Our SlurrySucker is available for outright purchase which is a popular option currently, but we also offer the unit on a rental or project agreement where our team will conduct the work for the end-user,” Venter concludes.

AFRISAM ENCOURAGING APPROPRIATE BEHAVIOUR OF CEMENT CONSUMERS

With South Africa’s carbon tax in force from 1 June this year, AfriSam is providing customers with transparent pricing and the ability to make greener choices.

According to Richard Tomes, sales and marketing executive at AfriSam, the way the company complies with the new carbon tax is aimed at encouraging the appropriate behaviour of consumers. Rather than apply a blanket price increase, AfriSam is allocating the amount of carbon tax due on each bag of cement.

The carbon tax is a levy that varies according to the amount of carbon emitted in the manufacture of a product. The different cement brands in AfriSam’s range contain varying amounts of clinker – the most energy-consuming element of cement. This means that the carbon footprints of the brands differ from each other.

“We are taking a transparent and responsible approach to the new tax,” says Tomes. “By showing the amount of carbon tax payable on each specific bag of cement, our customers will still see the base price that we are charging. This avoids any confusion about how much of the final price is going toward the tax.”

He notes that this approach will also make it easier for customers to identify the AfriSam cement brands with lower carbon footprints.

“We believe that a tax should not just be a punitive tool, but it should also affect behaviour in society,” he says. “Just as cement producers are working hard to reduce carbon emissions, so the end-user can also play their part by choosing an environmentally-friendly brand.”

While certain specialist cements demand higher clinker content, he says AfriSam increasingly uses extenders to create high-quality cement brands with lower environmental impact.

SUCCESSFUL CONSTRUCTION OF CRESTAQUARIUM BY CONCOR BUILDINGS

The indoor CrestAquarium at Cresta Shopping Centre allows shoppers to view more than 30 species of fish. Constructed by Concor Buildings and unveiled to the public in June 2019, this ‘edu-tainment’ feature is on the lower level of the centre’s food, entertainment and cinema court.

Specialist Italian experts provided the pure cast acrylic blocks for underwater use, and Martin Muller, contracts manager at Concor Buildings explains that one of the first challenges during the project was the logistics of getting these large acrylic panels into place.

“The panels were shipped in two pieces, each measuring five metres in diameter and four metres high,” Muller says. “With each item weighing about four tonnes, they were transported in jigs and trolleyed into the confined space of the shopping centre.”

To create enough space to access the lower level, one of the shopping centres escalators was removed completely to facilitate access for the trolleys. A spider crane, positioned on the food court level above, was used to lift and position each panel. The weight exerted by the crane’s activities was considered during this operation, with back propping of the slab on which it rested being done.

Various other technicalities related to the CrestaAquarium’s operation were also attended to by Concor Buildings. This included two pump rooms and acclimatisation baths for the fish which were used before they were introduced to their new home.

“After establishing the cast concrete base for the CrestAquarium structure, we also installed service ducts for water reticulation,” Muller says. “Another important aspect was the pressurised extraction system used to prevent dust ingress.”

Concor Buildings also built insulated panels around the acrylic structure, which ensured the required heat levels allowing the panels to bond and cure over a number of weeks.

“The next phase was quite technical, with the top of the CrestAquarium being covered with a fibre-reinforced plastic cap, including stainless steel components to avoid corrosion,” says Muller. “An added consideration in almost all our work on this project was that we were working in a live environment. The centre was busy with shoppers and visitors, so it was important as always that we worked with safety as a priority.”

The final aspects of the project included the placing of custom-made, marine themed mosaics in the floor around the CrestAquarium, and hydro-testing of water pressures and equipment. Concor Buildings started on the project in August 2018 and completed it in May 2019.

SOUTH AFRICA SEES VALUE FROM FLSMIDTH’S NEXTSTEP INNOVATION

FLSmidth’s innovative nextSTEP™ flotation technology is proving itself in the South African mineral processing space.

According to Ricus van Reenen, Regional Product Line Manager – Separation at FLSmidth, the nextSTEP™ rotor and stator combination has been at work for over a year at a large South African platinum mine, achieving positive results.

“The customer has achieved significantly lower power consumption on the full-scale retrofits we installed early in 2018,” says van Reenen. “The more efficient design allows the same or higher slurry circulation at reduced rotor speed, leading to lower power draw.”

The retrofits have been applied to both primary and secondary flotation applications, where energy savings of over 10% have been achieved. Years of research and development have been invested in the nextSTEP™ technology, which was originally launched in 2015.

Among the key design elements are the addition of slots to the stator, adjustments in the rotor profile and a parallel distance between the rotor and stator.

“Energy dissipation is now more uniform than in traditional forced-air designs,” van Reenen says. “This means a more even wear pattern across the rotor and stator, and therefore longer intervals between maintenance.”

In the South African installations, the wear on the rotors and stators has been minimal after more than a year’s operation. In the one flotation cell, the equipment has been operational for 15 months. The thickness of the rotor has reduced from 65 mm to only 60 mm, and the stator from 75 mm to 70 mm. After 13 months of operation in the second installation, the wear is even less. The rotor’s thickness has reduced from 65 mm to 63 mm, while the stator was down from 75 mm to 73 mm.

Van Reenen highlights that there have been other benefits experienced by local users of the new technology. Among these has been 16 to 18% less blower air usage, with more concentrated bubble formation.

“Better turbulence energy dissipation around the rotor and stator region, with its related finer bubble size distribution, creates more surface area for bubble-particle attachment,” says van Reenen. “This has delivered more froth and a higher mass pull on our local units.”

The success of the nextSTEP™ technology has led to further retrofits being planned in South Africa, which is in line with FLSmidth’s drive to promote mines’ productivity and performance. Van Reenen says the intensive R&D process continues apace and is not just in the rotor and stator design but also includes areas such as smart control systems and continued digitalisation of process solutions.

SAFE, RAPID DEMOLITION OF RUSTENBURG PELLETISING PLANT

A turnkey demolition contract is underway at a chrome pelletising plant in Rustenburg, after being secured by Forte Demolition Solutions.

A subsidiary of surface materials handling expert SPH Kundalila, Forte Demolition Solutions is tackling the project with its specialised range of mechanical dismantling and demolition equipment.

“Our investment in this equipment is substantial, making us the ideal partner for mines and other operations who need to address closure in a safe and sustainable manner,” says Graeme Campbell, group commercial operations manager at SPH Kundalila.

The plant to be demolished includes several multi-storey structures, conveyors, steel frames and concrete work, as well as large, heavy componentry. Campbell emphasises that Forte Demolition is one of few companies in South Africa with the necessary assortment of fit-for-purpose machinery and attachments. These ensure that the cutting and breaking process is safe and efficient. It also allows many components to be carefully dismantled for resale purposes.

“Among the factors behind our cost effectiveness is that we can shorten customers’ timeframes,” he says. “For example, our precision cutting is done by a shear attachment on an excavator. The power of hydraulics – combined with our specialised technology – means that everything is much quicker and safer.”

Equipment that is being employed on the pelletiser site includes a pulveriser for concrete demolition. It breaks concrete into small pieces that can be used as backfill on site, obviating the need for transporting large concrete chunks to special dumping sites. Other specialised demolition attachments that make Forte Demolition Solutions’ work both productive and safe are grapples, hammers and buckets.

High levels of safety are ensured by an integrated safety, health, environment and quality (SHEQ) management system, according to Brad van Niekerk, project manager at Forte Demolition Solutions.

“Safety is our key priority, which is enhanced by the closely supervised use of our mechanical equipment,” says van Niekerk. “This ensures that workers are not placed at risk by being too close to dangerous working environments.”

He notes that each project is planned and monitored by a skilled professional team, which takes the safest demolition approach. This is also aligned with customer standards to ensure full compliance with corporate and regulatory requirements. The company is also experienced in asbestos removal.

“With our own dedicated asbestos decontamination units and decontamination equipment, we can safely conduct demolition and disposal of asbestos cement, wall cladding, pipes, gutters and other fixtures,” he says. “We work closely with a registered hazardous waste removal specialist to ensure full regulatory compliance.”

A 51% black-owned business and Level 2 B-BBEE contributor, Forte Demolition Solutions operates nationally through its offices in Fochville, Rustenburg, Stilfontein and Carletonville.

HYDRAULICALLY DRIVEN DEWATERING PUMPS ADDED TO INTEGRATED PUMP RENTAL FLEET

No two pump rental applications are unlike, and it is this understanding that has positioned Integrated Pump Rental as one of the leading pump rental operations in South Africa.

Managing director, Lee Vine, says that some dewatering applications are simple plug-and-play operations where access to electric power is not an issue, but others, especially in remote or difficult to reach areas, require the use of diesel driven pump sets. “Large diesel driven pump sets are not always the answer where electricity is not available and to provide customers with a effective solution we recently introduced the Quax hydraulically driven pump range into our fleet.”

Not only will these hydraulically driven submersible pumps complement the existing Integrated Pump Rental fleet by filling the gap between the electrically operated submersibles and those powered by diesel, it will also open opportunities for the company to extend its reach into other markets. Vine says these include dewatering on construction and infrastructure projects in built-up areas as well as in the wastewater treatment sector.

“Quax is well proven in Europe. It is a reliable workhorse that can pump in all sorts of conditions. Apart from dealing with large particles and sludge, the pumps work particularly well where suction lift can be an issue,” Vine says.

The Quax range of submersible pumps includes a 2”, 3”, 4” and 6” unit, and all units are equipped with a run-dry capability which is considered essential in dewatering applications. The pumps are simple to install and operate, and offer reliable pumping even under challenging conditions. This, Vine, says enables end-users to dewater effectively in areas that are traditionally difficult to reach.

The pumps are equipped with a range of impeller option, increasing the versatility of these units. This includes a two bladed impeller for dealing with large particles, a screw impeller for pumping in thick sludge, a stainless steel impeller for applications with a low pH and a high head impeller.

Each hydraulic powerpack is well suited to the individual pump making it compact yet powerful, and each has an automatic shutdown feature should the installation operate outside of its set temperature parameters. The silent powerpack is fully enclosed which reduces noise during operation and makes these units suitable for operation in suburban area.

All pumps are supplied with the requisite accessories for the dewatering application at hand, and this includes pump hose flotation devices.

Quax hydraulically driven submersible pump are available from Integrated Pump Rental for outright purchase or for rental.

KWATANI RECOGNISED FOR LOCAL MANUFACTURE

Recognised as a finalist in the SACEEC Exporter of the Year Awards held in Johannesburg recently, Kwatani is one of few local manufacturers that holds an ISO 9001:2015 quality certification as well as a Level 1 B-BBEE rating. Significantly, the company was placed in the Exporter of the Year Large category and came second in the Export of the Year Africa category.

As one of South Africa’s leading vibrating screen OEMs, Kwatani understands the major role that local manufacturing has to play in the country. In addition, and of enormous advantage to mining operations in Africa, the company is the only South African vibrating equipment OEM independent of international technology and employs a far higher percentage of engineering personnel than others in this sector.

Kim Schoepflin, CEO of Kwatani, says that while recent amendments to the Mining Charter place even greater emphasis on the local manufacturing of mining equipment and products, it is vital to meaningfully measure exactly what ‘local content’ means in the mining environment.

“We can proudly say that Kwatani’s screening machines are locally manufactured,” Schoepflin says. “Our equipment is designed in our own in-house facility by our competent engineers and then built under stringent quality control conditions in our Spartan plant. This allows us to contribute significantly to job creation and economic transformation.”

While the Charter has certain local content requirements, the devil is in the detail. Government agencies like the South African Bureau of Standards (SABS) and the Department of Trade and Industry (DTI) are working with industry on a system to verify local content.

“The process of determining a supplier’s level of local content is complex,” Schoepflin says. “It is vital that the right tools are developed to place all players on an even playing field. Measuring local content must be meaningful and accurate, if it is to be effective.”

She notes that Kwatani’s long history of manufacturing locally has brought many benefits to mining customers. The company has a legacy of more than 43 years, and can point to fit-for-purpose screening machines installed across a wide spread of commodity sectors including coal, iron ore and other heavy metals.

“A key benefit of being a fully local OEM is that we can control quality,” she says. “With our suppliers close by, this facilitates close collaboration, quick turnaround and integration into our quality systems.”

Schoepflin highlights that the long term relationships with local suppliers means that everyone in the supply chain is committed to quality manufacture. This enhances the quality of the final product, while raising the capacity of even the smallest players in the supply chain.

By investing continuously in its own local research and development, Kwatani has ensured that its screening machines stay at the cutting edge of technology. This means recruiting and developing experts in both mechanical and metallurgical engineering. Local skills also fill all other aspects of the business, from technical and financial to administration and marketing.

FAST-TRACK REPURPOSING OF BMW GROUP FACILITY COMPLETED BY CONCOR BUILDINGS

Concor Buildings has completed the fast-tracked repurposing of BMW GROUP South Africa’s disused parts distribution warehouse on their Midrand Campus, Gauteng, delivering a new Dealer training centre, welcome/brand centre, and the information technology (IT) competence hub for the luxury motoring Group.

According to Concor Buildings’ site agent Blaine van Rensburg, the whole project was to be built within existing structures, with extensive demolition and bulk earthworks required. The main scope of the contract included a new Dealer training centre for technicians from BMW Group’s dealer network, office space for the IT staff, a ‘green lung’ multi-purpose area, and repurposing of the old training centre on site to house a gym, restaurant and welcome centre and other ancillary facilities.

Work began in May 2018 and construction was completed March 2019. The team moved off site at the end of May 2019. The training centre, says van Rensburg, has been constructed to include both technical and non-technical training facilities.

“The technical training areas are double-volume workshops, each constructed to meet the specific requirements of a particular trade or apprentice level,” he says. “This area also includes three plant rooms for air conditioning facilities, a server room and ablution facilities.”

A key aspect of the primary construction project related to inserting office space within the disused warehouse, generally referred to by BMW GROUP as the “IT Competence Hub”, further improving the digital linkages between BMW’s South African operations and other countries in the worldwide Group.

“The demanding specifications for this area included acoustic-rated drywall, glass and aluminium partitioning for office spaces and meeting rooms and ceilings which are rated for both fire and acoustic performance, as well as similar specifications for the 4,500 m2 over-sheet roofing system,” he says. “These specialised ceiling and roofing systems contribute to the energy efficiency of the building.”

Two smoke extraction shafts were installed, as well as two server rooms and five HVAC plant rooms.

He notes that constant and uninterrupted digital connectivity on the BMW campus was non-negotiable during the construction process, as the site housed not just the national head office but also BMW Financial Services and the BMW On-Call service’s fibre reticulation, which is the backbone of their network functionality and linked to the global network. All excavations therefore had to be particularly careful of existing underground services.

“Brownfield projects like these tend to pose particular challenges, as there is not always complete certainty about existing site conditions and building services,” he says. “There are several measures that we adopt, however, to help gain a better understanding of these factors which ensures the project schedule is not disrupted or delayed, and potentially eliminates the risk of damage to the property.”

For instance, pilot trenches were excavated where possible to expose existing underground services and avoid damaging them. Land surveillance of the existing benchmarks or control points was conducted to double-check the survey information provided; the older the building, the less certainty can be assumed, he notes.

“Where building services were exposed during excavation of the pilot trenches, these were surveyed and plotted onto a drawing by our registered land surveyor,” says van Rensburg. “This helped both the construction team and the client to improve our knowledge of the services in place.”

The green lung area – which will be used for recreational and social purposes – benefited from an innovative adjustment in terms of how to deal with a large retaining wall.

For a start, an existing concrete block retaining wall of about 950 m2 in size – as well as 1,800 m3 of hard rock and 3429 m3 excavated soil – were removed. Instead of replacing this with a reinforced concrete wall, the project design team agreed to the construction of a permanent lateral-support gunite wall. This significantly reduced construction time and complemented the industrial look-and-feel that the design team envisioned at inception.

Culverts and channels for underground services were installed adjacent to the base of the wall. Planters, staircases and seating areas were then constructed to beautify the area in front of the wall and increase its functionality.

The old training centre building was also refurbished in line with BMW Group sustainability targets and now houses a state of the art welcome centre, restaurant and production kitchen and a staff gym and yoga deck. Relooking the overall circulation routes on site now sees this building being the primary visitor entrance and playing an important role as the brand centre/welcome centre for all visitors to BMW Group South Africa. This multi-purpose area has a layout that can be altered to suit the company’s marketing requirements at any stage, including the display of vehicles, motorcycles and museum pieces inside the building.

The project included the conversion of a truck delivery area on the eastern side of what was previously the warehouse into an open-air parking area for staff and associates. The visitors’ parking was also reconfigured and expanded to accommodate double the number of visitor vehicles. On the western end of the site, an energy centre has been created housing the main plant related to the new building services, including a modern and efficient HVAC system. In this is area is also waste management and storage space, as well as offices and ablutions for facilities management staff. Adjacent to the energy centre is another open-air parking area which will used by the apprentices and lecturers.

“A further time saving innovation – introduced in consultation with the design team – was in relation to the offices and training centre on the first floor,” he says. “We managed to save on the application of over 4,000 m2 of plastering and paint on what would be brick walls, opting instead to construct acoustic drywalls. This reduced the scaffolding and wet works required, ultimately saving considerable time on constructing the area.”

Van Rensburg highlights that, due to the timeframes and complexity of each area of the project, it was necessary for construction work to take place on all faces almost simultaneously.

“For us to ensure that each area was getting the attention it deserved, we approached each section of the building as a mini-project on its own,” he says. “Concor Buildings and our subcontractors then assigned dedicated resources to each area, ensuring that the momentum was maintained and that the same teams who started an area would also finish it.”

Another challenge that was creatively resolved was the space limitation in certain areas, where it was not possible to gain access with moving plant or machinery that would typically have been used. This was facilitated by Concor Buildings’ purchase of industrial-grade steel trolleys, which were large and strong enough to move general materials around. They were used to stack items like full-size plywood boards, glass, aluminium, bricks, plaster material, structural steel beams, and ceiling and drywall material.

“This process meant that less manpower and less physical exertion was required for material handling and we believe this contributed to a lower fatigue rate, which in turn helped us maintain the outstanding safety record that we achieved on this project,” says van Rensburg.

BOOYCO’S VEHICLE DETECTION SYSTEM INTERVENES TO IMPROVE SAFETY

As a leader in proximity detection systems, Booyco Electronics is well known for its proximity detection system (PDS) that keep pedestrians safer in the underground mining environment. Its next advance has been to develop a vehicle detection system (VDS) that triggers interventions to prevent vehicle-to-vehicle accidents in line with EMERST guidelines.

Booyco Electronics’ new VDS is an innovative evolution of the company’s vehicle-to-vehicle detection system, and now incorporates the necessary high level of accuracy to introduce interventions in the operation of the vehicles.

According to Booyco Electronics engineer and developer Frank Schommer, the Booyco VDS is applicable in both surface and underground environments.

The system can measure the distance between the vehicles in a range from 10 metres up to 100 metres, with a measuring accuracy of 1 metre; not only can it determine the position of a vehicle but also the direction in which it is travelling.

“This means that the operator will be informed if another vehicle is close by, as well as the number of vehicles there are in the proximity,” says Schommer. “Based on a high frequency wave transmission, the new VDS technology has been developed to comply with the latest safety regulations for moving vehicles on mines.”

While these high frequencies do not penetrate rock in underground mining environments like low frequencies can, they are able to perform the vital duty of detecting other vehicles at a greater distance. Like the pedestrian PDS, the Booyco VDS’s functionality is based on different ‘zones’ within the radio field around each vehicle that is created by a transmitter; the distance of each zone from the vehicle can be defined by the customer, depending on their actual conditions and specific vehicles on site.

“For example, the system can be set so that it delivers a warning to the operators at a distance of 50 metres,” he says. “If no action is taken after that warning, and the distance between the vehicles is reduced, then a second zone is entered, and a command is generated for the operator to reduce speed. If speed is not reduced and the vehicles continue to get closer to each other, an intervention is triggered by the system to slow the vehicles down.”

The accuracy of the system ensures that there is sufficient reaction time after warnings are given for the operator to act, reducing the possibility of a collision.

While the system caters for larger vehicles with longer distances between them – such as on-surface load and haul operations – it is also applicable underground as it can measure long distances between machines through tunnels.

Booyco Electronics’ tried and tested PDS system – which is based on very low frequency (VLF) wave transmission – can penetrate tunnel sidewalls underground; this allows the detection of pedestrians who are out of sight around a corner, but over shorter distances.

“It is therefore optimal to use the VDS and PDS systems together on the same vehicle to achieve higher levels of safety,” says Schommer. “Combining these technologies allows mines to improve safety between vehicles – where the distances to be measured are longer – as well as between vehicles and pedestrians – where it is important to detect workers who are closer but not visible to the operators.”

FLSMIDTH’S FERROCER® PANELS BRING LONGER WEAR LIFE TO AFRICA

Trials of FLSmidth’s FerroCer® modular impact wear panels will soon begin in Africa, following successful trials in countries such as Australia, Peru and India, where significant increases in wear life were recorded. Tests will be conducted on sites in Zambia and Mozambique.

According to Zwerus Voges, Ceramic & Wear Solutions Specialist at FLSmidth, the innovative FerroCer panels represent a significant breakthrough in materials technology. The cost effective solution provides much better wear life than conventional panels and also delivers safety benefits to mine operators.

“The design of the panel takes advantage of the wear characteristics of multiple materials, and its matrix combines the strength and malleability of steel with the abrasion resistance of ceramics,” Voges says.

Each panel weighs only 5kg and can easily be handled by one person, meeting all the safety regulations for size and weight. The compact shape also makes the panels safe and easy to install using standard hand tools.

Voges says that the panels have delivered longer wear life in various applications which has meant increased uptime for customer operations.

FerroCer impact wear panels are particularly suited to high impact wear locations in a process plant, and these include chutes, hoppers, bins, feed boxes and vibrating screen boxes as well as reclaimer and loader buckets.

The panels have excelled in nickel, gold, copper and zinc applications, and Voges cites an example where FerroCer impact wear panels provided a solution in a tripper chute application. At this mining operation the previous panels in use were having to be replaced every three to four weeks, resulting in increased unplanned shutdowns with associated costs.

“Since the FerroCer panels were installed over a year ago, not a single panel has had to be replaced in that application,” he says.

Based on the success of the original FerroCer panel design, FLSmidth recently developed the FerroCer® 22 product for lighter applications where the material size is smaller. The larger ceramic surface area coverage on the panel reduces wear on the steel matrix. These panels weight only 2,8kg.

All panels are secured by just one bolt and nut, and no scaffolding or cranage is required. This enhances the safety and health of workers during installation, while speeding up the process.

The compact size of the FerroCer panels also makes it easier to replace just the worn panels. This is a major advantage, especially where wear patterns are uneven and not all the panels in an installation require replacement.

Voges highlights that the cone shape of the ceramic inserts enhances their resilience. It also means that the panel wears more slowly over time, as the surface area of ceramic insert widens as it wears.

“The much longer wear life being achieved by the FerroCer panels translates into reduced total cost of ownership, which is a primary driver across all commodity sectors,” Voges concludes.