含硫油品储罐自燃性的影响因素

含硫油品储罐腐蚀产物-硫化亚铁氧化放热是引起含硫油罐着火的主要原因。研究了供氧条件、油、单晶硫、硫化亚铁粒度对硫化亚铁自燃性的影响。实验结果表明,当空气流量是2.6mL/min时,硫化亚铁氧化速率明显快于1.4mL/min空气流量下的硫化亚铁的氧化速率。说明流量越大,氧化反应越快。因此,空气进入油品储罐内对储罐的安全运行构成重大威胁,为保证安全,油品储罐在付油过程中应及时向储罐内通入惰性气体;当有少许油覆盖在硫化亚铁表面上时,油层会阻碍硫化亚铁与空气中氧气充分接触,抑制硫化亚铁氧化反应的发生;硫化亚铁粒度为20～40目时,其氧化速率高于粒度在80～100目范围内的硫化亚铁的氧化速率。说明粒度越小,氧化反应越易发生,引发储罐自燃的危险性越大;单晶硫存在时,超过熔点会加速硫化亚铁的氧化。

Effect Factors of Spontaneous Combustion of Oil Tank Containing Sulfur

Fires in the oil tanks are caused by the thermo-oxidation of ferrous sulfide which is corrosive products of oil tanks containing sulfur. The investigation of the effects of flow rate of air, the existence of oil, monocrystal sulfur and particle sizes of ferrous sulfide on spontaneous combustibility of FeS was carried out. The experimental results show that the oxidation reaction rate of FeS at the 2.6 mL/min flow rate of air is faster than that of FeS at the 1.4 mL/min. So the oxidation reaction rate is accelerated when the flow rate of air is increased. Thus air entering into the oil tanks is the serious threat to the safe running of the oil tanks. To be safe the inert gas should replace the air to enter oil tanks in the process of discharge. The oxidation reaction is restrained when the surface of ferrous sulfide is covered by crude oil, since the existing oil layers prevent the reaction between ferrous sulfide and the oxygen in the air. the oxidation reaction rate of FeS with particle sizes between 20 and 40 mesh is faster than that of FeS with particle sizes between 80 and 100 mesh. So the finer the particle size of ferrous sulfide is, the greater the risk of self-ignition of oil tanks could become greater; the oxidation rate is accelerated after monocrystal sulfur is melted.