含硫油品储罐腐蚀自燃理论及实验研究

Experimental and Theoretical Study on Erosion of Tanks Containing Coking Gasoline

含硫油品储罐腐蚀自燃事故是炼油企业安全生产的重大威胁。对含硫油品储罐腐蚀进行了实验模拟研究 ,并对实验结果进行了分析 ;利用扫描电子显微镜对试样腐蚀表面进行了特征分析 ,并利用X射线仪对腐蚀产物的组成和结构进行了分析。实验研究结果表明 :相同腐蚀介质对各种钢材的腐蚀速度不同 ;不同油品对相同材质的钢材的腐蚀速度也不相同 ;从腐蚀产物结构分析可以看出含硫油品储罐腐蚀产物主要是由FeS、FeS2 、Fe3 S4、Fe9S8等成分组成的混合物 ;从焦化汽油硫含量和硫分布来看 ,油品中含硫量越高 ,对储罐的腐蚀越严重。在实验研究结果分析的基础上 ,理论研究分析了含硫油品储罐腐蚀自燃机理 ,探讨了含硫油品储罐腐蚀自燃影响因素。理论研究表明 :焦化汽油储罐自燃的根本原因是由于储罐内壁腐蚀生成了焦硫化铁 ,焦硫化铁自燃而引起油罐燃烧 ;油品种类、储罐材质、空气中含氧量、环境温度是影响含硫油品储罐腐蚀自燃的主要因素。

Self-combustion accidents of tanks containing coking gasoline are a great threat to the safety production in oil refining enterprises. The simulating experiment study about it was performed. A few kinds of steel materials including A 3, stainless steel, 20 # and aluminum were used in the experiment. The experimental samples can be direct erosion samples and steel samples with dope. The experiment results could be analyzed by the mass difference of samples before and after the experiment. The erosion can be removed by both mechanical and chemical reaction methods. The characters of the sample surface and the composition and structure of erosion resultants were analyzed by electron microscope, X-rays instrument respectively. The result shows that the erosion rate of different steels is different not only to the same kinds of oil but also to the different oil. The erosion production of steel to oil comprises FeS, FeS 2, Fe 3S 4 and Fe 9S 8. The higher the sulfur content is, the more serious the erosion of coking gasoline to tanks is. On the basis of the analysis of the experimental study, the mechanism of erosion and spontaneous combustion of tanks containing coking gasoline was studied. The key factors to the erosion and self-combustion of tanks containing coking gasoline were also discussed. It can be concluded from theoretical study that spontaneous combustion of tanks containing coking gasoline is mainly caused by the erosion productions of tanks. The type of oil, the steel materials, the content of oxygen and environmental temperature are influence factors to the erosion and self-combustion of tanks containing coking gasoline. The study results are available for the safety design of tanks containing coking gasoline and the improvement of production of coking gasoline.