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REPROCESSING AND TAILINGS REDUCTION Course Gangue Rejection R Circuit Featuring the Eriez HydroFloat® ® CY Y CLONE OVERFLOW It would also potentially result TO CONVENTIONAL FLOTA T A TION -160μ 2-ST T AGE SCREENS CYC Y CLONE E OW UNDERFLO in more metal and minerals being recovered as cutoff grades fall in line with the reduced need for grinding. FRESH MILL FEED Treating water right B ALL MILL HF CONC TO REGRIND +700μ CIRCULAT A T ING LOAD In this example of coarse gangue rejection ERIEZ HYDROFLOAT A T® from Eriez Flotation, the cyclone underflow passes through a set of sizing unit operations, here shown for illustrative COARSE purposes as a set of screens with 160-micron TA AIL B ARREN T and 700-micron apertures Water specialist Talbot, in January, launched a state-of-the-art mobile unit that enables mining and mineral resources players to test a highly efficient and cost-effective water treatment and mineral product recovery solution right on site. conventional flotation and to regrind the HydroFloat concentrate, a significant portion of the tail will now be in the coarse size range.” The proportion of final tailings that can be produced in the coarse size class will depend on the optimisation of the flotation process for the HydroFloat, which will increase as the effective size range of feed to the HydroFloat also increases. “While the results will be application specific, it is expected that the mass of final fine tails could be reduced by at least 30% and replaced with the same amount of coarse tail,” Wasmund said. “This The mobile unit is able to demonstrate the effectiveness of Vibrating Sheer Enhanced Process (VSEP) technology, a solution developed by US company New Logic Research Inc, which not only treats highly contaminated and difficult water streams to municipal quality, but is able to recover valuable product from residue that would otherwise be consigned to waste. The VSEP membrane typically out-competes other technologies on highly contaminated streams that have elevated concentrations of scalants, which solids/salts,” she told IM. “The vibration on the VSEP module prevents these blocking or damaging the membrane pores and flushes them out with the brine. You can push the system much further with minimal pre-treatment.” In mine waters, this is critical, according to Lipsett, as elevated and broad range contaminants are often present. “We also see extreme pHs and variability which simply cannot be tolerated on traditional membrane systems.” While treating contaminated and difficult water streams is the main order of business for Talbot and the VSEP, Lipsett said product recovery also comes into the mix. Precious metals operations, for example, provide a strong business case for the VSEP as the membrane can remove micro and nano particles, where centrifuges and presses only remove the micro particles. Should mining companies recover this metal from the membranes, there remains the potential for additional revenue. And looking beyond simply metals/mineral recovery revenue, VSEP could also allow mines to generate general use “permeate” from their process water. This can be used as a raw water source or would mean less grinding energy, smaller mills and a smaller fraction of the overall concentrator output that needs to be dewatered and stored in a exceed the feed concentration of conventional membranes, according to Claire Lipsett, General Manager – Consulting Services at Talbot. “If you concentrate a compound beyond processed further to potable quality and distributed to local communities, according to Lipsett. Lipsett said: “This guarantees their operating licence and ensures their compliance to community sustainability” – an aspect of operating a mine that conventional fine tailing impoundment.” precipitation potential, you will produce is becoming increasingly valuable. IM ABSOLUTE MATERIAL FLOW CONTROL CHUTE SYSTEMS & SOLUTIONS t0QUJNVNNBUFSJBMnPX t6QUPEFDSFBTFJONBUFSJBMEFHSBEBUJPO t3FEVDFEEVTUBOEOPJTFMFWFMT t7JSUVBMMZNBJOUFOBODFGSFF t(SFBUMZSFEVDFETQJMMBHF t4JHOJmDBOUSFEVDUJPOJOCFMUEBNBHF Tel: +27 (0) 11 827-9372 email: [email protected] www.webachutes.com MAY 2020 | International Mining 17