IM 2020 March 20 | Page 35

WATER MANAGEMENT & TREATMENT Weir Minerals can also conduct testing at customer mine sites to assess the viability of various tailings management strategies. “Weir Minerals believes that the dewatering of tailings has a fundamental role to play in this, and continues to push the boundaries of possibility,” it said. As the mining industry gains a better understanding of tailings, it is vital new and improved methods of containment and storage are developed. Dry stack tailings is now a big focus area. Chris Knowles, Director of Sales and Marketing APAC, McLanahan Corporation states: “Without a socially acceptable plan to responsibly deposit and rehabilitate these areas you have no project, and community expectations are increasing around dry tailings. Multiple technology options exist to produce and stack dry tailings. There are no technical limits to achieving this, only a cost implication. Tailing management is a large and complex business. Extensive studies on geochemistry are required to identify a suitable location; mining engineers and rock mechanic specialists are required to prepare the TSF; geotechnical consultants will define and plan the deposition of material and process engineers and equipment vendors design and provide the equipment appropriate to the deposition plan. In our experience, the larger mining companies are in fact taking great steps toward alternative tailings handling initiatives.” McLanahan was pleased to be offered an opportunity by Vale a number of years ago (and well before the dam collapses at the Samarco operation and then at Vale’s Brumadinho mine) to participate in a project to assess the feasibility of initiating dry stack tailings for key sites. This project involved working with site operations personnel and an Australian mining process consultancy, to undertake tailings slurry sampling in order to form a reasonable understanding of the sample range. Settling and filtration testing was conducted to a point where the client was sufficiently confident to invest in a pilot plant. Fast forward to the current timeframe and McLanahan has been selected to manufacture the tailings thickener for this site. “Our expert thickener team re-conducted onsite assessments to determine material variability and to review current tailings slurry output against the earlier baseline results. As expected, over a number of years the mining plan varies, depth of deposit changes and the mineral process is modified, giving rise to new optimisation initiatives in the pilot plant.” De.mem ‘s bauxite wins Water and wastewater treatment company, De.mem, says it has recently received new orders worth a minimum A$470,000 ($317,202) of revenue from Metro Mining for work at its Bauxite Hills mine in Queensland, Australia. The orders include the delivery of wastewater treatment equipment, plus a contract award to supply equipment in combination with the provision of operations & maintenance services under a build, own, operate, transfer (BOOT) agreement. Bauxite Hills, which produced 3.5 Mt (wet) of bauxite in 2019, is currently carrying out detailed engineering and design work related to a stage two expansion at the mine, which could see annual operating capacity reach 6 Mt (wet) by 2021. De.mem CEO, Andreas Kroell, said: “We are pleased to provide our customers with a complete water treatment solutions offering, which includes the flexibility of either purchasing or leasing equipment from De.mem. Our build, own, operate/BOOT solutions are a key part of our services business, whereby we are engaged by leading players from mining and other industries under long-term agreements for the provision of water treatment equipment and ongoing operations and maintenance services.” This is not the only Queensland bauxite mine De.mem is currently working on. Back in February 2019, the company secured a 12-month A$780,000 operations and maintenance contract to manage potable water and sewage treatment plants at Rio Tinto’s Amrun bauxite mine in the state. De.mem has operated the water treatment plant at Rio’s $1.9 billion operation since 2016 on a SUSTAINABLE SOLUTIONS FOR PROFITABLE MINING TOMRA’s sensor-based ore sorting solutions deliver proven improvements in recovery and profi tability in a wide variety of mining operations, including tin, gold, lithium, diamonds, coal, quartz, chromite, tungsten and phosphate. They maximize effi ciency, precision and speed, capturing even the smallest particle sizes with technologies that include Color, Near-Infrared (NIR), X-Ray Transmission (XRT), Electromagnetic and Laser sensors. Energy-effi cient, cost-eff ective, green mining.