含硫油品储罐中硫化铁自燃引发事故原因分析

Cause Analysis of Spontaneous Combustion Accidents Caused by Iron Sulfide in Oil Tanks with Sulfur Contained

通过分析含硫油品储罐中活性硫的主要组成及对油品储罐的腐蚀方式,总结了含硫油品储罐中硫化铁的生成方式、自燃性及其主要影响因素。分析认为,尽管活性硫对设备的腐蚀形式多样,但低温湿H2S腐蚀是活性硫对油品储罐的主要腐蚀方式,腐蚀产物极易自燃而引发油品储罐发生火灾和爆炸事故。建立了含硫油品储罐硫化铁自燃事故的故障树(FTA)图并对其最小割集的分析认为:储罐防腐涂层脱落、水的存在和原油含硫是引起顶事件发生的最重要基本事件。通过故障树分析,探讨了硫化铁自燃事故的主要原因并提出相应的预防措施。

The formation ways, pyrophorisity and its main influencing factors of iron sulfides in sour oil tanks are summarized by analyzing the main composition of active sulfur in sour oil tanks and its corrosion conduct to tanks. It is considered that the corrosion of humid hydrogen sulfide to tanks at low temperatures is the main corrosion ways even though the corrosion ways are diverse. The corrosion products are easy to combust spontaneously and cause fire ＆ explosion accidents in the tanks. A F＇FA （fault tree analysis） logic chart of fire accidents caused by spontaneous combustion of iron sulfides is built. The minimal cut sets obtained from this fault tree shows that the destruction of anticorrosive coating in tanks, the existence of water and the sulfur contained in oil are the most important basic events that cause spontaneous combustion accidents. Besides, other main causes leading to spontaneous combustion accidents of iron sulfide and corresponding countermeasures are also explored through FTA.