火三含蜡原油管道初凝现象分析

Analysis on the Part-gel-shutdown Accident in Huoshaoshan-Beisantai Crude Oil Pipeline

通过对火三含蜡原油管道初凝现象以及对其处理过程中的运行参数进行分析,认为连续运行的管道,其下游的进站温度应控制在输送介质的凝点+3℃温度以上;间歇运行的管道,末站进站温度应达到安全停输时间的要求,以保证管道在冬季安全运行。对于含蜡原油管道的初凝现象,三个过程主导着压力、排量的变化和管道恢复正常的速度,第一是管内空隙的充装过程,第二是使末段部分低温原油屈服的过程,第三是冲刷、剥落管壁凝油层,恢复管道正常排量的过程。

By analyzing a waxy crude oil pipeline's part-gel-shutdown accident, following concepts are recognized: (l)For a waxy crude oil pipeline ,downstream outlet temperature of the pipeline must be 3 C higher than its pour point; (2)when a part-gel-shutdown waxy crude oil pipeline will be restarted,three processes dominate the changes of pressure and flow rate as well as the speed of pipeline's normalization. First one is filling the empty space caused by shrink or weight-flow. Second is yielding the end-segment lower temperature gel crude oil that has yield stress. The last one is scouring and cleaning the part-gel crude oil nearby pipeline wall and recovering normal flow rate.