基于可靠性的海底湿气管道水合物生成概率研究

Study on Reliability-Based Hydrate Formation Probability for Subsea Wet-Gas Pipelines

海上油气集输过程中,天然气水合物的生成可能会造成管线堵塞,威胁到油气田正常生产。借鉴油气管道强度可靠性评价方法,结合前人对水合物生成条件预测模型的研究成果,建立海底湿气管道水合物生成概率计算方法。案例分析表明,管道水合物生成概率随着各随机参数的标准差增加而增加,同时全线水合物生成概率稳定所需的随机样本个数也随之增加。对与水合物生成概率相关的随机参数进行敏感性分析,入口压力作为随机变量时的标准差变化对管道水合物生成概率影响最大,入口流量的影响次之,入口温度的影响最小。

In the process of offshore oil & gas gathering and transportation,the formation and blockage of hydrates in subsea pipelines will threaten the normal production of oil & gas fields. In this paper, the calculation method of hydrate formation probability in subsea wet-gas pipelines was established based on reliability method and previous studies of hydrate formation condition prediction model. According to the case study, the hydrate formation probability increases with the increase of the standard deviation of random variables. The sample numbers when the probability tends to be stable increases with the increase of the standard deviation of random variables. The change in standard deviation of inlet pressure has the greatest impact on the hydrate formation probability in subsea pipelines based on the sensitivity analysis, followed by inlet flow rate and temperature.