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MINERAL SEPARATION RIEGL VZ-2000i for TOPOGRAPHY AND MINING high-accuracy h hig ig gh acc gh-acc RIEGL VZ-2000i scan data Long Range, Very High Speed 3D Laser Scanning System » RIEGL LiDAR Waveform Technology for high accurate data (5 mm) » rapid data capture with up to 1.2 million measurements/sec » extensive coverage with up to 2500 m range » smart operation by remote scanner control and onboard software apps » outstanding efficiency through automatic onboard registration capabilities, customizable workflows, and connectivity via LAN, Wi-Fi, 3G/4G » for topography and mining: surface modeling, toe & crest line extraction, change detection, cut & fill volume calculation, and slope gradient angle control VISIT US AT May 27-29, 2019 | Helsinki, Finland | RIEGL booth 3 Stay connected with RIEGL between 300-400 g/t Ag to the float circuit as flotation recoveries are maximised within this range. The plant currently achieves overall upgrades of approximately 150% of feed grade with the IPJ-only circuit producing an average 180% increase from calculated feed grade,” he said. The benefits of this IPJ circuit at Pirquitas included the installation of a very low energy gravity circuit, increased overall grade to the mill, increased metal to the mill, water recycling in the gravity circuit due to the coarse feed, and a lower capital cost for the downstream plant. Gekko has also recently installed the biggest IPJ of its class, the 250 t/h IPJ3500, at New Gold’s New Afton mine site in British Columbia, Canada. This came alongside a 100 t/h IPJ2400 and the company’s Mag Screen technology – the latter designed to both screen and remove magnetics from final concentrate. At New Afton, the continuous gravity separation machines are recovering the native copper from the supergene ore, according to Rasmussen. As this installation shows, Gekko is more than just a gold-focused company. “Most of the focus has been on gold, but we also do a lot of work with sulphides,” Rasmussen said. “If your ore and your gangue are very close in terms of specific gravity, it makes it harder to carry out effective ore separation but, if there is a noticeable difference, the equipment can be applied.” And, Rasmussen wanted to dispel any perception that the pre- concentration work Gekko and others carry out competes with ore sorting. “People think ore sorting and pre-concentration are competitive, but they are not; they are collaborative,” he said. “Ore sorting basically goes down to 15 mm and that’s where pre-concentration picks up – they work together.” For those companies worried that a pre-concentration phase could end up reducing the downstream throughput in an operation, Rasmussen offered up this response: “With pre-concentration, you can lower your cutoff grades and positively affect your economics. Quite often waste is a cost, but if you can even get to a breakeven point on that, you have effectively paid for your stripping.” Gekko’s pre-concentration technology is also in place at TMAC Resources’ Hope Bay gold mine in Nunavut, Canada, in two 1,000 t/d pre-concentrator lines containing secondary crushing, grinding, flotation and gravity gold recovery equipment. In this installation, the Gekko Pythons are fed by a primary jaw crusher, according to TMAC. A concentrate treatment plant (CTP) then processes the gravity and flotation products. TMAC has recently completed the installation of additional gravity concentrators in the plant; two FLSmidth Knelson XD20s have been installed to capture fine gravity recoverable gold in the concentrate treatment side of the CTP regrind circuit. Their installation included the reconfiguration of Gekko IPJs and spinners to the CTP in recirculation with the screening circuit, with those changes completed by the end of October. The operation’s Sepro Mineral Systems Falcon SB400 gravity concentrators in each of the concentrator lines have also been upgraded to Falcon SB1350s. This will enable the plant to treat the entire flow within the primary grinding circuit, rather than solely the recirculating load, according to TMAC. Two Falcon C2000s, which are expected to scavenge gravity recoverable gold and sulphides from the cyclone overflow feeding the flotation cells – thereby further reducing losses to tailings – have also come online. These changes are geared towards TMAC upping recoveries to at least 90% from its Hope Bay processing plant. Gettin’ jiggy with it www.riegl.com RIEGL LMS GmbH, Austria | RIEGL USA Inc. | RIEGL Japan Ltd. | RIEGL China Ltd. | RIEGL Australia Pty Ltd. 16 International Mining | MAY 2019 Yunnan Hualian Zinc and Iridium Co recently awarded allmineral with a contract to supply three advanced alljig ® units for its latest pre- concentration project.