四川某气田集输管线积液影响规律研究

A Study on the Law of Liquid Accumulation Influence in Southern Sichuan Wet Gas Pipeline

伍坤一 张露露 林宇 李蔚熹 周军

WUKunyi ZHANGLulu LINYu LIWeixi ZHOUJun

中国石油西南油气田公司集输工程技术研究所, 四川 成都 610051 中国石化皖能天然气有限公司, 安徽 合肥 230088 西南石油大学石油与天然气工程学院, 四川 成都 610500

Research Institute of Gathering and Transportation Engineering Technology, Southwest Oil & Gas Field Company, PetroChina, Chengdu, Sichuan 610051, China Wanneng Natural Gas Co. Ltd., SINOPEC, Hefei, Anhui 230088, China Petroleum Engineering School, Southwest Petroleum University, Chengdu, Sichuan 610500, China

针对四川某气田起伏湿气集输管道积液严重问题，基于全动态多相流模拟软件(OLGA)仿真模拟建立了积液模型，考虑了输气量、输液量、压力及温度对管内积液量的影响，揭示了管内积液随输气量、压力、输液量及环境温度的变化规律。绘制了积液版图，直观展现积液变化趋势，为气田分析积液影响提供一定的数据支撑。由于大落差起伏管线流型变化复杂，因此，分析了不同工况下流型的演变过程，结果表明，积液最先在较长的上倾管段形成环状流，随积液增多逐渐向上堆积形成段塞流，直到管内全部充满积液。在积液规律基础上，建立并模拟了混输和分输工况的清管作业，研究了最小输气效率法、最大积液量法和最大允许压降法确定清管周期的可行性。结果表明，对于混输工况，最大允许压降法确定清管周期最长为4.5 d；对于分输工况，采用最大积液量法确定清管周期最长为32.0 d。

In order to solve the serious problem of liquid accumulation in the undulating wet gas gathering and transporting pipeline of a gas field in southern Sichuan, a liquid accumulation model is established based on OLGA simulation software. The influence of gas volume, infusion volume, pressure and temperature on the amount of liquid accumulation in the pipeline is taken into account, and the change rule of liquid accumulation in the pipeline with gas volume, pressure, infusion volume and ambient temperature is revealed. The map of liquid accumulation is drawn, and the change trend of liquid accumulation is displayed directly, which provides certain data support for analyzing the effect of liquid accumulation in gas fields. Due to the complexity of flow pattern variation in the pipeline with large drop fluctuation, the evolution process of flow pattern under different working conditions is analyzed. The results show that the liquid first forms annular flow in the long updip pipe section, and gradually accumulates upward to form slug flow with the increase of liquid accumulation until the pipe is full of liquid accumulation. Based on the law of liquid accumulation, the pigging operation under mixed and separate transportation conditions is established and simulated, and the feasibility of determining pigging period by the methods of minimum gas transfer efficiency, maximum liquid accumulation amount and maximum allowable pressure drop is studied. The results show that the pigging period of the maximum allowable pressure drop method is 4.5 days for mixed transportation conditions. The pigging period is determined to be 32.0 days by the method of maximum liquid accumulation.

10.11885/j.issn.1674-5086.2022.07.23.01