硫化亚铁自燃反应特性及活性抑制研究

Study on spontaneous combustion characteristics and activity inhibition of ferrous sulfide

为了揭示硫化亚铁自燃引起油气储罐和炼油设备着火、爆炸机理,探索硫化亚铁自燃事故防治技术,分别以氧气、空气为反应气,通过同步热分析仪分别测定活性硫化亚铁样品及经钝化处理后的样品(简称钝化样品),在室温～800℃范围内的反应,采用等转化率法分别计算活性样品及钝化样品在氧气气氛下反应的表观活化能。结果表明,活性样品在氧气下的反应包括室温自燃和高温段分解两个阶段;在空气下的反应包括室温自燃、中温氧化及高温分解三个阶段,最终产物均为Fe_2O_3;钝化样品室温无法自燃,在氧气或空气气氛下,钝化样品加热至100℃左右发生氧化。经计算,在氧气气氛下,活性样品表观活化能为57.101 kJ/mol,钝化样品表观活化能为235.985 kJ/mol,钝化处理可抑制样品的活性。

In order to reveal the mechanism of ignition and explosion of oil and gas storage tanks and oil refining equipment caused by ferrous sulfide,and to explore the prevention and control technology of spontaneous combustion accidents of ferrous sulfide,oxygen and air were used as reaction gases respectively to determine the active ferrous sulfide samples and passivated samples by synchronous thermal analyzer.The temperature range was from room temperature to 800℃.The apparent activation energy of the active and passivated samples in the oxygen atmosphere was calculated by the iso-conversion method.The result shows that the reaction of the active sample under oxygen atmosphere included self-ignition at room temperature and decomposition at high temperature.The reaction under air atmosphere included auto-ignition at room temperature,oxidation at medium temperature and pyrolysis.The final product was Fe2O3.The passivated sample could not ignite itself at room temperature spontaneously.The passivated sample was oxidized at around 100℃in an air or oxygen atmosphere.The apparent activation energy of the active sample under oxygen was 57.101 kJ/mol,and the apparent activation energy of the passivated sample was 235.985 kJ/mol.The passivation treatment achieved the purpose of inhibiting the activity of the sample.