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REPROCESSING AND RETREATMENT technology, it is possible to process materials of very different types and consistencies without any problems; for example in order to produce granulates from slurries under the addition of dry materials. “In the process, agglomerates are disintegrated in the best possible way so that the end product offers an excellent quality of mix, even if auxiliary substances such as chemicals are added in the ppm range. The good self- cleaning effects and the system-related low wear of the mixer are often important aspects.” In addition to mixers that operate on a batch basis, EIRICH sees the advantage of using “continuous” mixers. “For example, it has been shown in the processing of tailing mounds from magnesite production that these mixers offer significant process and cost advantages. One of the advantages here is that – unlike in batch mode – there is no time needed for filling and emptying. In addition, smaller mixers with lower input power can be used,” the company said. EIRICH’s mixing technology also brings advantages to other recycling tasks, including waste processing, landfill engineering and the reprocessing of contaminated sites. “Examples include the agglomeration of dust from steelworks for recirculation to the sintering “The super-phosphoric acid also contained toxic phosphogypsum waste during continuous operation of its new demonstration plant in the US. The Improved Hard Process – or IHP – for producing phosphoric acid for agricultural and industrial use, the company says, “is one of the about 2 ppm of cadmium, with about 80-90% of cadmium in the phosphate feed being eliminated during the process and captured in pollution control scrubbing systems. The process also significantly reduces levels of other trace heavy most significant advancements in many decades for the phosphate industry”. The technology is a kiln-based process that metals, such as lead and arsenic,” the company said. Timothy Cotton, CEO of JDCPhosphate, said avoids direct acidulation of phosphate rock, minimising the amount of waste and “completely avoiding” phosphogypsum production,” JDC this process development was a major milestone for JDC and its technology, “showcasing IHP’s value as a cost-efficient and scalable new said. “Instead, IHP co-produces a commercially useful aggregate for construction and road building called J-Rox.” During recent operations at its demonstration plant in Fort Meade, Florida, JDC was able to process”. He said: “Given the limited phosphate rock reserves in the world, it will be critical for future generations that we waste as little as possible of operate its entire process continuously – including feed preparation and agglomeration, induration, reduction, oxidation, and acid production – to produce the product using phosphate rock waste tailings from local mining operations. The company said: “The phosphate raw material contained an average of about 14% phosphate as P 2 O 5 , with high levels of silica and other impurities, including magnesium oxide. The company combined this low-quality phosphate material with clay and petroleum coke to make these vital resources. At the same time, we need to minimise the production of toxic phosphogypsum wastes and reduce the level of harmful impurities in phosphate products. The IHP technology will become a critical part of the global phosphate production chain.” JDC is now further upgrading its commercial demonstration plant for on-demand and sustained operations. By early 2019, the company planned for the Fort Meade plant to be capable of testing various qualities of phosphate ore raw material, allowing potential licensees to validate the process for the phosphate ore and silica sources they have available. JDC will then complete its process design engineering for conveyor or for addition to reduction processes, or for the agglomeration of converter dusts containing zinc for input into the Waelz process,” EIRICH said. “Special mixer designs are used for its kiln feed.” The feed was then processed in the kilns and acid plant at the demonstration plant to produce super-phosphoric acid at a concentration of 68% the processing of contaminated soil or – in the form of so-called vacuum mixers – for the drying of paint/enamel sludge with explosion P 2 O 5 with less than 2.5% impurities, including less than 0.3% CaO, 0.2% MgO, 0.3% SO 4 , 1.0% commercial-scale applications of the IHP technology. The company also is exploring optimal routes to commercialisation of IHP, including expanding Fe 2 O 3 , 0.1% F and 0.1% Al 2 O 3 . its operations in Florida. IM protection.” In addition, heated mixers are available for special applications (up to 250°C), EIRICH said. EIRICH concluded: “Every mixer is specially designed for the relevant purpose. The company’s internal test centres are available all around the world for the performance of customer trials so that process parameters can be defined. EIRICH can also supply suitable rental mixers for subsequent upscaling tests, allowing the cost-effectiveness of the preparation process to be tested at a larger scale.” Building your digital ecosystem to connect your mine to the future. Rock retreatment JDCPhosphate recently used its patented Improved Hard Process technology to produce high- quality super-phosphoric acid (SPA) from low-quality phosphate rock tailings without creating www.mstglobal.com [email protected] Australia | United States | Canada | Chile | South Africa | Russia | United Kingdom | China MAY 2019 | International Mining 13