LNG工艺管线清洁方案研究

Study on Cleaning Scheme of LNG Process Pipeline

液化天然气(LNG)工艺管线在预制、安装、试压等施工过程中会产生铁屑、焊渣等杂物,必须进行清除。目前管线常用的清扫方式主要有清洁球、水射流、空气清扫和人工清理等方式,LNG工艺管线相较于普通管线结构较为复杂,流动介质温度低易燃易爆,并且安装有较多的精密仪表,因此LNG工艺管线一般采用空气吹扫的方式进行清洁。通过理论计算分析与浙江某现场实践相结合的方式,对管线空气吹扫原理、现场施工步骤与最终的管线清洁效果都进行了详细阐述,现场成功经验对今后LNG接收站项目工艺管线空气吹扫实践具有一定的借鉴意义。

In the construction process of prefabrication,installation and pressure test,the LNG process pipeline will produce iron filings,welding slag and other sundries,which must be removed.Currently used cleaning ways mainly have pipeline cleaning ball,water jet,air cleaning and manual cleaning,LNG process pipeline compared with ordinary pipeline structure is relatively complex,flow medium temperature low flammable and explosive,and more precision instrument installed,so LNG process pipeline generally USES clean air purge.By combining theoretical calculation and analysis with a field practice in Zhejiang province,the pipeline air purging principle,field construction steps and the final pipeline cleaning effect are described in detail.The successful field experience has certain reference significance for the future LNG receiving station process pipeline air purging practice.