Capital Equipment News December 2017

MINING NEWS

TDS delivers extensive infrastructure at Finsch Mine

Ground rules for reducing magnetite losses in dense medium plants

TDS Projects Construction is completing a mammoth installation of extensive ground handling infrastructure at Petra Diamond’s Finsch Mine. The project, which commenced in November 2014, was awarded to TDS Projects Construction by Petra Diamonds following a successful tender pro- cess. TDS Projects Construction’s affiliated company, Thuthukani Engineer- ing Solutions designed the C-cut ground handling infrastructure at Cullinan mine and were then tasked with the design of Finsch’s infrastructure re- quired for the sub-level caving expansion project. The project (phase 1 completed, phase 2 in progress) includes the fabrication, construction and installation of nine tipping points, five ore pass retaining walls, four bulkheads, two crusher stations with overhead cranes and four conveyors. Phase 1 commenced on November 20, 2014 and was completed on March 25, 2016, while Phase 2 commenced on April 4, 2016 with completion estimated for July 2018. Hennie Coetzee, MD of TDS Projects Construction says the success- ful execution of the project thus far is a testament to the depth of the expertise and commitment of the team. “TDS is capable of continuously adapting to the challenges and changes of a construction environment. Our experience in the construction of mining infrastructure allows us to be innovative when presented by particular requirements dictated by a project or site. This is evident in aspects of the project such as the ore pass retaining walls, which are pre-casted and a first of their kind for un- derground operations and allow flexibility for the construction of tipping points on multiple levels simultaneously,” says Coetzee. The bulkhead structures include steelwork well in excess of 100 t per bulkhead and were installed at the bottom of a 5,1 m diameter ore pass, ranging from 70 to 190 m in height. One of the bulkheads consists of a staggering 165 t of steel, 150 m³ of concrete and 15 t of reinforcing to be constructed within a matter of four months – while the conveyor system constructed at Finsch covers a distance of 1 650 m at an incline of 9 de- grees and was completed within a construction period of 13 months. b

Speaking after the Southern African Coal Processing Society’s biennial conference in Secunda recently where Kwatani, represented by Jeremy Bosman, presented a paper addressing the impact of appropriate screen selection on dense medium recover, Kim Schoepflin, CEO of Kwatani, highlighted the importance of adhering to certain ground rules. “Across the different pro- cesses, there are basic prin- ciples that are common, such as the use of drain and rinse screens to recover magnetite from the product and reject streams,” says Schoepflin. She says a concentration of magnetite in the dilute me- dium must also be achieved to give a suspension of high relative density, or overdense, medium using wet drum mag- netic separators. Schoepflin outlines the fun- damentals to be observed in restricting magnetite losses, regardless of which screen- shortly

ing arrangement is chosen. “The feed arrangement onto the screen must ensure that the full width of the screen is utilised,” she says. “Low feed velocities are also critical, as this maximises the drainage rate on sieve bends and multi- slope screens.” She emphasises that the drain section, which includes both static and vibrating screens, must have sufficient area to recover 95% of the medium being fed to it, and that allowance must be made for potential blinding which will reduce the open area of the screen. “It is vital to take the av- erage particle size and bed depth into account when se- lecting the screen width,” she argues. “Running at too high a bed depth will increase medi- um carry-over from the drain to the rinse section, and will also reduce the efficiency of the rinse water in washing off the medium; this in turn will lead to an increase in magne- tite losses.” b

First Joy reclaim feeder manufactured in Wadeville

Joy reclaim feeders currently operate in a variety of applications, including coal mining operations.

tive method of blending materials, reclaiming stockpiles and feeding material. The machine features automatic operation at low speeds, low maintenance costs and high flexibility for blending applications from multiple stockpiles. Joy reclaim feeders require only solid, level ground conditions for instal- lation and offer high mobility. Joy reclaim feeders currently operate in a variety of ap- plications including, but not limited to, synthetic fuel plants, power plant facilities, synthetic gypsum plants, truck load- out facilities, port load-out facilities and coal mining oper- ations. Komatsu recently highlighted the machine’s capabilities at an Open Day event on October 17-18 at its manufacturing facility. “We are excited to be producing these high-quality machines local- ly,” says Croydon Walters-Gerout, director – Marketing & Capital Sales. “This particular machine was designed and manufactured to customer specification, making it ideal for the unique conditions of our area.” b

Designed specifically to meet the challenges of the South African mining environment, the first locally-manufactured Joy reclaim feeder is now available from Komatsu. Produced at the company’s manufacturing facility in Wadeville, Gauteng, the machine was built using 75% locally sourced materials. Joy reclaim feeders are said to offer an efficient and cost-effec-

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