Abstract: Slug flow with varying degrees often occurs in gathering and transportation systems, which makes the flow in the pipelines fluctuate in a certain extent. The fluctuation caused by slug flow made the running of inlet devices in the gathering and transportation system and central treatment station unstable. The flow fluctuation at inlet must be considered when designing inlet devices (usually the primary separator) to inhibit shut down problems due to surpassed flow volume. Suitable design factors were usually considered to relieve the effect caused by flow fluctuation. However, the design factor usually could not solve the unstable problems completely, and dynamic simulation was very necessary. The inlet flow variation, terrain fluctuation and pigging conditions of a gathering and transportation system in a Middle East oilfield were simulated. It was found that the existing separator could guarantee the system operated stable though the inlet flow was fluctuated in a range. The design factor of the inlet primary separator equaled to 1.4 was caused by flow fluctuation.

Key words: Gathering and transportation system, Slug flow, Terrain fluctuation, Pigging, Dynamic study, Design coefficient

摘要： 油田集输系统中经常会发生不同程度的段塞流, 使集输管线流量发生一定程度的波动, 引起集输管网和集中处理站入口装置运行不稳定。在设计入口装置( 通常是一级分离器) 时需要考虑进站流体波动的影响, 以防止入口流量超过一级分离器设计处理量造成停产等事故。在设计分离器时, 通过选取合适的设计系数的方法可以在一定程度上减缓集输系统流量波动带来的影响, 但是经验系数的选取往往不能从根本上解决不稳定流动问题,必须对集输系统进行动态分析。对中东某油田集输系统中的入口流量、 地形起伏和清管等工况进行了模拟, 发现现有分离器在集中处理站入口油气不稳定流动的条件下能够保证稳定运行, 集中处理站入口一级分离器设计系数为1. 4的工况是因产量的波动而造成的。

关键词: 集输系统, 段塞流, 地形起伏, 清管, 动态研究, 设计系数