Tag Archives: Limpopo

DRA Global’s ‘total solutions offering’ put to the test at Exxaro’s Grootegeluk mine

DRA Global says it has continued to sustain its long-term client relationship with Exxaro Resources through the progressive engineering, procurement and construction management (EPCM) contract at the Grootegeluk coal asset in South Africa.

Exxaro’s Grootegeluk is an open-pit coal mine, 20 km from Lephalale in Limpopo province. The mine produced 26 Mt/y final coal products, using a conventional truck and shovel operation, and has an estimated mineable coal reserve of 3,261 Mt, and a total measured coal resource of 4,719 Mt.

“A project of this magnitude speaks to the extensive experience in project development and delivery extended to the client by DRA,” DRA says.

DRA’s specialist engineering expertise and total solutions package at Exxaro’s Grootegeluk includes, but is not limited to:

  • Bankable feasibility study;
  • Installation of a new PC2 Discard Conveyor alongside the current PC1 Discard Conveyor;
  • Installation of new bifurcated transfer chutes to discharge onto either PC1 or PC2 Conveyor;
  • Seven transfers in total that requires conversion; and
  • Construction of associated infrastructure; such as stormwater control, road crossing, new spillage collection and a transfer system.

Furthermore, DRA recently completed the 3D scanning of existing conveyors and accompanying infrastructure. The compiling of the 3D model has commenced and will inform the engineering of the various transfer towers and the new PC2 Conveyor onto the next phase, it said.

Exxarro, in 2018, initially awarded DRA a contract to construct a 500 t/h coal handling and preparation plant at the Belfast Implementation project, in Mpumalanga.

“The client’s faith in DRA showcases the proficiency in implementing large-scale coal projects and further solidifies the organisations’ reputation for successful project delivery (even under these new circumstances),” it said.

Alistair Hodgkinson, Senior Vice President at DRA, said: “Grootegeluk is just one of many projects under DRA that provides an excellent opportunity to showcase our engineering capability. This is a complex brownfields project that will require attention to detail to achieve successful construction during a tight shutdown deadline; the client values our reputation for being able to deliver challenging brownfields projects successfully.”

The project commenced in the September quarter and is forecasted for completion by the June quarter of 2021.

thyssenkrupp navigates South Africa lockdown to replace platinum mine HPGR roll

As the COVID-19 pandemic tightens its grip, thyssenkrupp Industrial Solutions says it is assisting customers in maintaining operational efficiencies through sustainable service delivery and innovative technologies.

“The global economic crisis, as a consequence of the COVID-19 pandemic, has put the drive for efficiency into top gear,” Philipp Nellessen, CEO of thyssenkrupp Industrial Solutions Sub Sahara Africa, said. “Fundamental to this drive is cutting-edge technology. Through our ongoing investment in people and R&D and our over 200 years of expertise, we are able to develop advanced technologies to assist mining and other industries in achieving maximum operational efficiencies.”

Although the South Africa mining industry was not operational during national lockdown Level 5, critical repairs were still permitted. As an essential service provider, thyssenkrupp has been delivering maintenance and repair as well as rebuild work to local mines.

The company assisted a platinum mine in Limpopo Province with a roll change on one of thyssenkrupp’s flagship products, a high pressure grinding roll (HPGR).

Nico Erasmus, thyssenkrupp Industrial Solutions Sub Sahara Africa Head of Service Operations, explained: “The scope of work required a rebuild on the HPGR set as well as the installation of the hardware on the mine site, making this our largest project in the national lockdown period.

“We are very pleased that even in a complete lockdown situation, we were able to complete the project in a healthy and safe manner, in excellent co-operation with our customer.”

The customer had “excellent controls” in place and thyssenkrupp complemented the risk mitigation with its own additional preventative protocols, he added.

Procedures included pre-selection of a team that falls inside the recommended age and health categories, pre-screening at both thyssenkrupp and customer sites, limiting the amount of people on shifts and in spaces, adhering to stringent hygiene measures (hand sanitising, wearing face masks, social distancing, cleaning of surfaces, tools and equipment), and implementing special transport and accommodation measures.

According to Erasmus, despite several challenges, the team adapted quickly to all the controls while still being responsive enough to get the work done safely and within the scheduled timelines.

“The transport of super loads (two trucks with 120 t loads each) was a real challenge, but our logistics team rose to the occasion and got the loads on site in no time and ready for installation,” Erasmus said.

To remain operational and continue seamless service delivery to customers, thyssenkrupp has implemented all necessary policies in line with South Africa Government COVID-19 regulations.

These include possession of all essential services permits and strict entry control protocols for employees, visitors and suppliers at all premises. Employees are required to attend mandatory training sessions conducted by the OSH department, wear all necessary personal protective equipment, sanitise regularly and maintain social distancing.

A dedicated COVID-19 committee has been set up to assess changing regulations and risks associated with office and site working environments, the company said.

“With the majority of employees working from home, we have faced our fair share of challenges but the process was very well organised with IT managing it all incredibly well ensuring that everybody was equipped in time,” Erasmus said. “We only had one day of downtime at our essential service workshop site.”

Wrapping up, an optimistic Nellessen says he is in no doubt that South Africa/Sub-Sahara Africa will recover.

“The people here are incredibly brave and innovative and companies will find their way out of the crisis,” he said.

“Despite tough times ahead for some industries, the mining sector continues to show growth and here I foresee a restart and a good recovery, depending on mining commodities probably taking anything between three to 12 months to reach previous and required pricing levels.”

Weir’s Warman AHF slurry pumps cut through the froth in South Africa

Weir Minerals’ Warman® AHF pumps have been put to the test at two mines in South Africa’s Limpopo Province, the company said.

The pumps were tasked with pumping frothy, high density and viscous slurries at the platinum and phosphate mines.

Weir said: “Handling froth in some process circuits can be very challenging, as froth will air-bind a conventional slurry pump. In froth applications, the Warman AHF inducer impeller solves this problem, producing far less surging. The inducer impeller and oversized inlet enhance the movement of the froth, high density or viscous slurries into the impeller, facilitating effective transportation.

“In addition, its higher efficiencies mean a smaller pump will deliver the required results.”

At the platinum operation, a Warman AHF 2 pump was commissioned in early 2016. It has met the specified flow rate of 40 m3/h with no pump-related stoppages, repairs or replacements, according to Weir.

A 12-month trial period showed the unit saved the mine over R200,000 ($14,153) when compared with the cost of the competitor pump installed previously. Based on this, the mine replaced another eight competitor products with Warman AHF pumps, Weir said. It has approved the Warman AHF 3 pumps as standard for all frothy applications at the plant’s first flotation section, and Warman AHF 2 pumps for the second flotation section, the company added.

The Warman AHF pumps – with Hi Seal® expeller (dry gland) design – were also tested in a viscous slurry application at the phosphate mine in Limpopo for six months. According to Weir, they demonstrated they could continuously pump the high-density viscous underflow slurry at relative densities above 1.9. “As a result, the customer purchased the pump and began upgrading all the remaining concentrate thickener underflow pumps to the Warman AHF pump technology,” Weir said.

This reduced the plant’s operational costs significantly, decreased dewatering and concentrate moisture extraction operations, improved filtration efficiency and increased concentrate throughput to the dryers, according to Weir. The Warman AHF pump also extended the underflow pumping boundaries and the overall reliability of the thickener underflow pumping system.

“Other field and laboratory tests have proven that the Warman AHF pump has largely overcome the problem of high-density viscous underflow slurries, with negligible effects on head at slurry yield stresses up to 200 Pa,” the company said.

Jacques Pretorius, Weir Minerals Africa’s Pump Product Development Specialist, said the approach to solving any thickener underflow pumping problem must be based on a thorough understanding of the entire application, the mineralogy and rheological behaviour of the slurry.

“Successful thickener underflow pumping projects are only achievable through involving a team of thickener engineers, pumping engineers and rheological consultants,” he said. “Weir Minerals’ pump trial campaigns confirm the successful operability of the Warman AHF pumps in viscous slurry applications.”

Murray & Roberts Cementation to sink ventilation shaft at Palabora copper mine

Murray & Roberts Cementation says it has been awarded a contract by Palabora Mining Co for a 1,200 m deep ventilation shaft at its copper complex in Phalaborwa, Limpopo Province, South Africa.

The shaft, with a lined diameter of 8.5 m, will reach a final blind sink depth of 1,190 m before a drop raise takes it to its final depth, according to Braam Blom, Project Executive at Murray & Roberts Cementation.

“The duration of this project is expected to be just over three years,” Blom said. “After mobilisation, site establishment and surface civils have been completed, we expect to conduct pre-sinking until the end of 2019, with the use of our special shaft sinking gantry to a shaft depth of 65 m.”

A surface headgear and winder installation will then be constructed from January to March 2020. This will facilitate the slow sink to 200 m and the main sink until February 2022. Canadian shutter and lining methods will be employed, the company said. The team is expected to conduct shaft stripping by mid-April 2022 and to dis-establish the site by the end of May 2022, it said.

“There will be no stations or other excavations required, so this will help keep the team in a sinking cycle and optimise production levels,” Blom said. “We will run full calendar operations with 12 hour shifts and cycles of five day shifts, five night shifts and five shifts off.”

A relatively small labour force of 123 people is planned for steady main sinking conditions, with some sub-contractors conducting surface piling and civil works for the winder, headgear and other site construction. Shaft drilling itself will be done with two twin-boom Komatsu shaft drill rigs, and mucking by a Komatsu excavator with close to 1 t of loading capacity.

Blom said ground conditions were expected to be a challenge in some areas, as profiled from the cover and core drilling “However, we have various ways of reducing the risk and downtime during these intersections – such as keeping the shaft lining as close as possible to the shaft bottom,” he said.

Palabora operates a large block cave copper mine and smelter complex employing around 2,200 people, according to the company’s website. It has developed a $410 million underground mine with a production capacity of 30,000 t/d of ore.