Modern Mining October 2019

PRODUCT News

TOMRA sorters show their worth at Renard

TOMRA developed a solution with four key objectives for the ore sorting plant: minimise diamond breakage by removing hard rocks from the crushing plant feed; upgrade the quality of the material to the process plant by increasing the propor- tion of kimberlite to waste rock; reduce the energy required for crushing by removing the harder rocks; and improve circuit effi- ciencies throughout the plant. TOMRA’s solution features five PRO Near Infrared (NIR) sorters in its ore sorting circuit. This technology is particularly well suited to enable discrimination between the various ore and waste materials that need separation at the Renard mine, based on their different chemical composition. TOMRA also provided a COM XRT 2400 sorter, which uses X-Ray Transmission (XRT) technology to separate material according to its specific atomic density in the plant’s large diamond recovery circuit. “The implementation of this plant proves that TOMRA waste sorting technol- ogy can successfully be used to upgrade lower grade ROM and that sensor-based sorting can be used to further improve value recovery for our clients on lower- grade resources,” comments Geoffrey Madderson, Diamond Segment Manager at TOMRA. TOMRA Sorting Mining, website: www.tomra.com/mining at the rock face at the customer’s mine removes the need for sample transporta- tion which leads to increased uptime and enhanced productivity for lowest total cost of ownership for the customer. tkISSA will also configure the machine into the cus- tomer flowsheet if required. “Not only are we responsible for the manufacture of the machine but, given the fact that it remains on the customer’s site for a relatively short period, we are also respon- sible for operation,” notes Van Wyk. He also points out that the company will provide an additional process engineer if the customer requires specialised tests. In the event of longer durations, thyssenkrupp will train the site personnel and empower them to oper- ate the machine themselves. thyssenkrupp has already received enqui- ries from America, Australia and Europe for this solution. Based on the experience gained by operating the unit, thyssenkrupp plans to develop Container Version 2.0 which will incorporate Industry 4.0 equip- ment as well as a wide range of upgrades. thyssenkrupp Industrial Solutions (South Africa) website: www.thyssenkrupp-industrial-solutions.com

Stornoway Diamonds is a leading Canadian diamond exploration and producing com- pany. It owns and operates the Renard mine, in commercial production operation since 2017. Conditions at the mine presented Stornoway with particular challenges that required an innovative approach. “Due to the geology of our ore, meaning we produce very high yield, we have lots of material that we need to sort through. At times, we have the possibility of losing some of those very expensive diamonds due to inefficiencies,” explains Marie-

Claude Hallé, Marketing Operations Manager for Stornoway Diamonds. She also points out that Renard’s ore- body contains a high level of internal and external dilution called country rock, a sig- nificant issue as it can make up to 30 to 40 % of the feed to the plant. “With that comes very, very high energy costs from crushing all this waste material that is not diamond bearing,” she says. “It causes a tremendous amount of wear and tear on our equipment from screening conveyors through to diamond recovery equipment, and on a dollar-per-tonne basis we spend a lot of money processing non- diamond bearing material.” TOMRA analysed the situ-

ation and worked closely with Stornoway Diamonds’ team to design and install a kimberlite pre-concentration plant. The specific conditions at Renard meant that the traditional DMS method could not provide an efficient and cost-effective solu- tion. It required an innovative approach, which TOMRA deliv- ered, making Renard the first diamond mine to incorporate ore sorting into its processing plant.

TOMRA sorting machines installed at Renard.

thyssenkrupp develops mobile HPGR test unit thyssenkrupp Industrial Solutions South Africa (tkISSA) has streamlined the sample testing process with the recent development of a mobile containerised High-Pressure Grinding Roll (HPGR) test unit. By enabling customers to test samples on site, this elimi- nates the costs, time delays and complex logistics related to the transportation of samples for testing purposes.

at tkISSA. When installed in the container, the unit features a ground-breaking plug- and-play configuration; customers only need to supply a main power connection. Depending on customers’ needs, the capabilities of the containerised laboratory include the ability to run single pass tests on numerous different material types. “This would be required to determine the HPGR’s specific performance parameters,” explains Van Wyk. In addition, this versatile lab is also able to process large quantities of sample through the unit, ready for downstream pro- cessing. “In fact, our very first unit, which we rolled out to a customer in Africa in Q2-2019, was used for the crushing of a massive 700 tonne sample, bearing testament to the suc- cess of our locally adapted design.” This unit was subsequently returned to the original installation in thyssenkrupp’s test facility and the first test campaign since its return has already been completed. This containerised lab offers a host of benefits; the fact the machine is deployed

The inspiration to create this distinctive containerised laboratory was spurred on by a customer who required the pre-crushing of uranium ore causing various dilemmas in ore processing and transportation logistics as well as handling of radioactive material. Taking all these factors into consideration, the company came up with a game-chang- ing idea: bring the test laboratory to the customer. The mobile laboratory consists of a semi-pilot scale HPGR fully enclosed in a 20-foot container. “The HPGR was developed in Germany, but we have adapted the design for manu- facturing in South Africa,” says Gerhard Van Wyk, Process Manager: Minerals Processing

46  MODERN MINING  October 2019