Sha Di, Li Yucheng, Zhou Xihua, Zhang Jing, Zhang Huan, Yu Jiaqi
College of Safety Science and Engineering, Liaoning Technical University, Fuxin 123000, China.
College of Safety and Emergency Management, Taiyuan University of Technology, Taiyuan 030024, China.
ACS Omega. 2021 Oct 6;6(41):27150-27157. doi: 10.1021/acsomega.1c03803. eCollection 2021 Oct 19.
To study the influence of different volatile contents on the explosion characteristics of coal dust, the volatile content in coal dust was controlled under different final temperatures of pyrolysis. The maximum explosion pressure, maximum pressure rising rate, and explosion index were used to characterize the pressure behavior, the pressure ratio to characterize the explosibility, and the minimum ignition temperature of the coal dust cloud to characterize the sensitive characteristics. A 20 L of nearly spherical coal dust explosion parameter measuring device and a dust cloud minimum ignition temperature measuring device were used to study the influence of the explosion characteristics of dust with different volatile contents prepared under different pyrolysis temperature conditions. The results showed that the volatile matter content in lignite dust has little effect on the maximum explosion pressure, with an average change rate of 5.435%. When the volatile content was reduced from 45.4 to 2.45%, the maximum explosion pressure rise rate dropped by 65.976%. The explosion index of the experimental sample was in the range of 0-1.6, with weak explosion characteristics; the lower the volatile content, the weaker the explosion intensity. When the volatile content was only 2.45%, the pressure ratio was still greater than 2, that is, the dust was still explosive. When the volatile content in lignite was reduced from 45.4 to 18.21%, the lowest ignition temperature of the dust cloud was consistently 490 °C. At this stage, the contents of H, CO, CH, CO, and other precipitated dases were low. When the volatile content was reduced from 18.21 to 2.45%, the precipitated volatile gas increased rapidly, the remaining precipitated gas content decreased, and the dust could not be easily ignited. The experimental results lay the foundation for studying the influence mechanism of volatile matter in coal dust on the explosion characteristics.
为研究不同挥发分含量对煤尘爆炸特性的影响，在不同热解终温条件下控制煤尘中的挥发分含量。采用最大爆炸压力、最大压力上升速率和爆炸指数表征压力行为，用压力比表征爆炸性能，用煤尘云最低着火温度表征敏感特性。利用20L近球形煤尘爆炸参数测定装置和粉尘云最低着火温度测定装置，研究不同热解温度条件下制备的不同挥发分含量粉尘的爆炸特性影响。结果表明，褐煤尘中挥发物含量对最大爆炸压力影响较小，平均变化率为5.435%。当挥发分含量从45.4%降至2.45%时，最大压力上升速率下降了65.976%。实验样品的爆炸指数在0 - 1.6范围内，爆炸特性较弱；挥发分含量越低，爆炸强度越弱。当挥发分含量仅为2.45%时，压力比仍大于2，即粉尘仍具有爆炸性。当褐煤中挥发分含量从45.4%降至18.21%时，粉尘云的最低着火温度始终为490℃。在此阶段，析出的H、CO、CH、CO等气体含量较低。当挥发分含量从18.21%降至2.45%时，析出的挥发气体迅速增加，剩余析出气体含量减少，粉尘不易被点燃。实验结果为研究煤尘中挥发物对爆炸特性的影响机理奠定了基础。
