外浮顶油罐雷击路径打火与防护技术研究

Study on sparking in lighting strike path of external floating-roof tank and its protection technology

近年来,大型外浮顶油罐屡遭雷击,发生油罐着火事故。从发生着火油罐看,这些油罐均按标准规范采取了油罐接地、浮盘安装接地连线、二次密封板安装了导电片等防雷措施,但仍出现了雷击油罐着火事故。从2009年开始建立大型外浮顶油罐雷电实验装置,并开展了实验研究。根据研究成果,论述了两个方面内容,一是阐述了大型外浮顶油罐遭雷击时的电流路线,电流在运动路径中产生的放电打火现象;二是阐述外浮顶油罐分路与分流技术,消除外浮顶油罐浮盘一二次密封闪络打火现象,避免一二次密封空腔闪爆着火。

In recent years,fire accidents caused by lightning on large external floating-roof tanks have occurred frequently. These tanks have already adopted lighting protection measures according to the standards,such as tank grounding,installing grounding connection on floating disk,and installing conductive sheet on the secondary seal plate etc. An experiment plant of large external floating-roof tank had been established and experimental studies have been carried out since 2009. Based on the research findings,two aspects contents were discussed in this paper. At first,the current path of external floating-roof tank being struck by lightning was illustrated,as well as the sparking phenomenon caused by the current in movement path. Secondly,the lightning current shunt technology of external floating-roof tank was presented,which can eliminate flashover spark of once and secondary sealing in floating disk and avoid fire in space between once and secondary sealing.