液化天然气公交车载缓冲罐意外爆炸事故的原因分析

Analysis on the Buffer Tank Explosion of a Liquefied Natural Gas Vehicle

针对一起液化天然气(LNG)公交车维修中发生的车载缓冲罐爆炸事故进行调查,从罐体材质、断口特征、介质特性及人为因素等方面进行了技术分析。调查认为:疑似供气管路或换热器出现故障,导致低温LNG汽化不完全,气态管路及缓冲罐出现LNG积液,并形成严重冰冻。使用常温水进行常规除冰处理,导致LNG积液在封闭空间内发生快速相变反应,气体急剧膨胀造成局部压力突跃,超过罐体所能承受的极限压力,最终造成缓冲罐爆破失效。

An explosion accident of bufer tank of a liquefied natural gas(LNG)vehicle during maintenance was investigated from the tank material,fracture characteristics,medium characteristics and human factors.The results show that the failure of gas supply pipeline or heat exchanger leads to incomplete vaporization and accumulation of LNG in gas pipeline and buffer tank,which are serious freezing.The water is used for routine deic ing,which leads to the rapid phase transition of LNG,and the rapid expansion of gas causes the local pressure jump of system.Once the limit pressure that the tank can bear is exceeded,the explosion accident of buffer tank can occur.