焙烧方式对石煤提钒效果的影响

Effect of Roasting Mode on Vanadium Extraction from Stone Coal

湖北某石煤矿石V2O5品位为0.72%,钒主要赋存在白云母等铝硅酸盐矿物中。为了低耗、高效提取其中的钒,对粒度为0.45-1 mm的试样进行了静态和流态化焙烧对比试验。结果表明,在较低的焙烧温度和较短的焙烧时间情况下,流态化焙烧可以取得较理想的焙烧效果,在750℃下流态化焙烧15 min,钒浸出率可达83.52%;在800℃下静态焙烧60 min,钒浸出率为74.93%。对焙烧产物的XRD和SEM分析表明：焙烧可以改善石煤浸钒效果的主要原因在于,焙烧可以破坏石煤中白云母的结构,将以类质同象形式赋存在白云母晶格中的钒释放出来,为酸性浸出液进入焙烧产物内部并浸出钒创造了条件。因此,流态化焙烧是改善石煤浸钒效果的低耗、高效手段。

A stone coal from Hubei Province contains 0.72% V205. The vanadium mainly occurs in aluminum silicateminerals like muscovite. In order to efficiently extract the vanadium from stone coal with low energy consumption, comparisontests of fluidized roasting ＆ static roasting were conducted on the ore, with particle size from 0.45 to 1 mm. The results indica-ted that, fluidized roasting can obtain ideal index in low roasting temperature with short time. The leaching rate of vanadium is83.52% when fluidized roasting at 750 ℃ for 15 min and is 74.93% when static roasting at 800 ℃ for60 min. XRD and SEManalysis of roasted products showed that main reason for better performance of vanadium extraction by roasting is that roastingcan destroy the structure of muscovite,liberate the vanadium from white mica crystal lattice, and make it possible on acid leac-hing liquid get into the interior of muscovite and make extraction more easily. Therefore, fluidized roasting can highly improvevanadium extraction effect with low consumption.