液化石油气管道极端压力工况探讨

Discussion on the Extreme Pressure of LPG Transportation Pipeline

目前,液化石油气生产与利用不断增长,其管道输送技术大力发展。管道系统的安全性与系统压力密切相关。液化石油气管道受介质物理特性影响,与常规原油、成品油液相管道在极端压力工况选择中存在特殊点。以液化石油气管道的极端压力为研究对象,结合钢制管道强度理论,剖析了压力对液化石油气管道影响的根源,基于常规液相管道极端工况探讨思路,分析了液化石油气管道在各种压力工况下的安全性与可靠性,根据液化石油气特殊输送工艺,研究并证实了液化石油气极强的热膨胀性对管道的极端影响。研究成果表明,液化石油气管道在清管、再启动下的系统压力与运行状态几乎一致,水击工况下压力有所提升,特殊的停输升温工况将压力激增,应采取对策。研究成果可为相关学者和工程人员提供参考与借鉴。

Presently, the production and usage of Liquefied Petroleum Gas （LPG） is growing, and the LPG transportation technology is developed greatly. The safety of pipeline system is closely related to the system pressure. There are some special points for extreme pressure in LPG pipeline system comparing with the common crude oil or product oil pipeline, because of the LPG physical property. Taking the extreme pressure in LPG pipeline as research object, the origin of impact of pressure on LPG pipeline is discussed basing on the steel pipeline strength theory, the safety and reliability of LPG pipeline is analysed under the common liquid pipeline extreme operation condition. The extreme influence of thermal expansion on pipeline from LPG is deeply studied and confirmed, according to the special working condition in LPG pipeline. The study results show that the extreme system pressure of LPG pipeline under pigging and re-start condition is almost same to that under normal operation condition, and the extreme pressure will be increased under surge condition, and then, the system pressure will rise greatly when pipeline shutdown and warming up, which must be considered for solution. The study result will provide reference for relative scholar and engineer.