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开发碳酸钠碱熔焙烧预处理红土镍矿的新工艺,对红土镍矿碱熔脱除铬和铝动力学以及矿石粒度和碱矿质量比、焙烧温度等影响铬和铝浸出率的因素进行系统研究。结果表明:在矿石粒度为44~74μm、碱矿质量比为0.6:1和焙烧温度为1000°C的条件下,铬和铝的浸出率分别达到99%和82%以上。在600-800°C温度范围内,除铬反应受产物层扩散控制,其表观活化能为3.9 k J/mol;在900~1100°C温度范围内,除铬反应受表面化学反应控制,其表观活化能为54.3 kJ/mol。此外,在600~1100°C温度范围内,除铝反应受Avrami内扩散控制,其表观活化能为16.4 kJ/mol。在后续对碱熔渣进行加压酸浸过程中,镍和钴的浸出率分别达到96.8%和95.6%。
The development of sodium carbonate alkali roasting pretreatment laterite nickel ore new technology, laterite nickel ore alkaline fusion removal of chromium and aluminum kinetics and ore size and alkali mass ratio, calcination temperature and other factors affecting chromium and aluminum leaching rate system the study. The results show that the leaching rates of chromium and aluminum reach 99% and 82% respectively when the ore size is 44 ~ 74μm, the mass ratio of alkali to ore is 0.6: 1 and the calcination temperature is 1000 ° C. In the temperature range of 600-800 ° C, the chromium removal reaction is controlled by the diffusion of the product layer, and the apparent activation energy is 3.9 kJ / mol. In the temperature range of 900-1100 ° C, the chromium removal reaction is controlled by the surface chemical reaction, Its apparent activation energy is 54.3 kJ / mol. In addition, the apparent activation energy was 16.4 kJ / mol at the temperature range of 600-1100 ° C with the Al removal reaction controlled by Avrami diffusion. In the subsequent pressure sour slag leaching process, the nickel and cobalt leaching rates were 96.8% and 95.6%.