对二甲苯海底管道反向输送温降数值分析

Numerical Analysis of Temperature Drop in Reverse Transportation of PX Subsea Pipeline

由于冬季海底环境温度低于对二甲苯(PX)的凝固点,为防止海底管道冬季停输凝管,采用反向输送的方式,使管道始终处于流动状态,避免凝管事故发生。管道采用保温形式,反输时冷液头的最低温度是考察的重点,要确保冷液头到达首站的温度高于其凝固点。利用OLGA仿真软件分析停输时间、反输流量、反输温度对海底管道沿线PX温度变化的影响,发现反输流量的影响较大。

Due to the seabed environment temperature in winter is lower than freezing point of para xylene(PX),in order to prevent subsea pipeline solidification when it shut down in winter,the reverse transportation was adopted to keep the pipeline in the state of flowing to avoid solidification accident.The insulation pipeline was used,the minimum temperature of the cold liquid head is the focus of the investigation to make sure that the temperature of the cold liquid head at first station was higher than the freezing point.The simulation software OLGA is used to analyze the influence of shutdown time,backflow flowrate,backflow tem⁃perature on PX temperature along the subsea pipeline.And it is found that the influence of reverse flow is more.