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DECEMBER 2015 • E&MJ; 89 www.e-mj.com P R O C E S S I N G S O LU T I O N S metric tons per hour (mt/h) and has been test- ed on a number of different typical bulk ore and slag samples from mines and smelters around the world, including massive sulphide ore from the Iberian Pyrite Belt in Spain. The ore and rare gangue minerals have been reduced in size by a reduction ratio of 480 and have been liberated to a high degree. According to the authors, these results are due to the unique working principle of the VeRo Liberator, which is based on high-frequency, high-velocity and, therefore, high-kinetic-energy impacts inflicted on the material by hammer tools. The hammer tools are mounted on three separate levels of a vertical axle-in-axle system and rotate at variably high speeds clockwise and counter- clockwise against each other. The material and particle stream within the machine is highly turbulent and each particle is struck with high-impact forces several times at a high frequency. These high-frequency and high-velocity impacts occur so fast that stress builds up along the particle bound- aries due to differential mechanical behavior of the inhomogeneous materials. Eventually this results in fracture for- mation along particle boundaries. This concept allows significantly more efficient comminution of ores and recycled materi- als at far lower energy costs and with far higher degrees of particle liberation. Due to its enormous reduction ratio, the VeRo Liberator can also replace two to three tra- ditional crushing and milling stages, saving substantially both in capex and opex. The machine is fed via an input funnel and a conveyor belt with feed size up to 120 mm. Maintenance is apparently quite easy. The main shell can be lifted quickly to replace the impact tools. The entire axle-in-axle system with all of the hammer tools attached can be pulled out of the machine and can be replaced by a standby unit in one piece. If, theoretically, a user has to exchange all the impact tools, it would take less than two hours. The con- figuration (number, size, weight and design) of the tools and the speed of the various tool levels can be modified sepa- rately. The VeRo Liberator can therefore be quickly adapted to various input materials. PMS Hamburg, the company behind development of the VeRo Liberator, is an engineering startup managed by the two sons of inventor Peter Michael Scharfe. Outotec's Flotation Cell Replacement Calculator Provides Fast Results Aging, underperforming flotation equipment can have a huge impact on a plant's metal- lurgical performance, energy efficiency, and ultimately, its profitability. This can cause challenges in meeting operational targets due to low concentrate output from cells, while equipment breakdowns have a nega- tive impact on availability and high spare parts costs affect operational profitability. Older plants are typically equipped with a large number of cells with relatively small volumes, meaning that metallurgical per- formance is far from optimal. Furthermore, operations need flexibility over time due to the variation in head grades, and this could require changes in both the capacity and flotation duty of some cells. Process equipment solutions provider Outotec announced recently that feasibility evaluation of flotation circuit modernization could become much easier due to a new value calculator it has developed. The tool, as described by the company, provides a fast and effective way to evaluate operating cost reductions and the overall value of process improvements that may be achieved by replacing aging flotation cells with Outotec's TankCell technology. Based on the given parameters and case-specific values for power, slurry and other variables, the tool can recommend a solution and also calculates the savings for the new solution. The calculator also shows how flotation cell replacement affects CO 2 emissions. In other words, Outotec noted, the tool provides a quick estimate for achieving a more effi- cient flotation circuit. Value gains can then be explored further with Outotec experts, based on more detailed variables and site specific considerations. The redesigned cir- cuit will deliver optimized cell volume and size, froth carry rate, and residence time. Clariant Highlights Advances in Flotation Chemicals Specialty chemical producer Clariant announced recently that one of its repre- sentatives had presented a paper at the seventh International Flotation Conference held in Cape Town, South Africa in November, describing what it termed "rev- olutionary" HOSTAFLOT products for cop- per mining. Clariant's Jacques Bezuidenhout, senior mineral processing engineer, presented the paper titled Clariant Collectors for Use as Alternatives to Xanthate Collectors in Traditional Sulfide Flotation Applications . In powder and pellet form, xanthates have been an industry staple for the collection of sulfide minerals for more than 90 years. However, in today's market, they pose health risks to workers, present disposal challenges to mining companies, may require addition- al infrastructure for handling, and are clas- sified as a fire and explosion hazard. Clariant Mining Solutions developed sev- eral new technologies in their HOSTAFLOT line of collectors, which are claimed to be effective alternatives to hazardous xanthate collectors. "This is groundbreaking new collector technology for those operations mining copper," said John Gordon, global head of Clariant Mining Solutions. "With the HOSTAFLOT products being shipped and dosed in liquid form, they offer high flotation performance and a safer handling and dis- posal solution than xanthates, can lower the capital expenditures for mines to convert pow- dered xanthate into a liquid solution, and pro- vide a longer shelf life than solid xanthate." In its initial configuration, the VeRo Liberator is fed by a conveyor belt carrying material up to 120-mm fragment size. Unit throughput is about 100 mt/h.