Spontaneous combustion tendency of fresh and pre-oxidized sulfide ores
Spontaneous combustion tendency of fresh and pre-oxidized sulfide ores
复制标题
DOI：
10.1007/s11771-014-1993-5
复制
发表时间：
2014-02-01
影响因子：
4.4
通讯作者：
Li Zi-jun
中科院分区：
文献类型：
--
作者：
Yang Fu-qiang;Wu Chao;Li Zi-jun
从典型金属矿山采集了3个具有代表性的硫化矿石样品，并在自然环境下获得了相应的预氧化产物。用同步热分析方法研究了样品在5、10、15和20A℃/min的升温速率下，在常温至800A℃的气流中的热行为，并比较了预氧化前后的TG/DSC曲线。根据DTG曲线的峰温，将每个样品的整个反应过程划分为不同的阶段，并用Ozawa-Flynn-Wall方法计算了表观活化能。结果表明，预氧化后各样品的反应过程较为复杂，反应速度较快，产热量较少，着火点或高或低。表观活化能从364.017-474.228 kJ/m o l降至244.523-333.161 kJ/m o l。因此，硫化矿石预氧化后更容易发生自燃。
Three representative sulfide ore samples were collected from typical metal mines, and their corresponding pre-oxidized products were obtained under nature environment. The thermal behaviors of each sample at heating rates of 5, 10, 15 and 20 A degrees C/min in air flow from ambient temperature to 800 A degrees C were studied by simultaneous thermal analysis and the TG/DSC curves before and after the pre-oxidation were compared. By the peak temperature of DTG curves, the whole reaction process for each sample was divided into different stages, and the apparent activation energies were calculated by the Ozawa-Flynn-Wall method. The results show that the reaction process of each sample after pre-oxidation is more complex, with quicker reaction rates, fewer heat production quantities, and higher or lower ignition-points. The apparent activation energies decrease from 364.017-474.228 kJ/mol to 244.523-333.161 kJ/mol. Therefore, sulfide ores are more susceptible to spontaneous combustion after the pre-oxidation.