深水油气管线天然气水合物生成条件预测方法及应用

在深水油气田开发中,为了有效防止天然气水合物的生成,迫切需要对天然气水合物生成条件进行准确预测。为此,根据深水环境压力高和多温度梯度的特点,应用气液两相流理论与传热学原理建立了适用于深水油气管线的温度预测模型;在现有实验数据的基础上,对5种天然气水合物预测方法进行了对比优选,结合Beggs-Brill方法建立了预测深水油气管线天然气水合物生成条件的模型,并编制了相应的计算程序。实例研究结果表明,管线流量越大、绝热材料导热系数越小、绝热层厚度越大、停产时间越短时,天然气水合物的生成区域就越小。该模型可用于制订合理的管线流量指标、选择恰当的管线保温材料和准确计算无接触时间,对深水油气田的安全生产提供了技术支持。

Prediction of gas hydrate formation conditions in deepwater oil and gas pipelines and its application

To effectively prevent the formation of gas hydrate in the development of deepwater oil and gas fields, it is necessary to perform accurate prediction of the gas hydrate formation condition. The temperature prediction model for the deepwater oil and gas pipeline is hereby established by means of gas liquid two phase flow and heat transfer theory in accordance with the features of high deepwater pressure and diversified temperature gradient. The optimal selection is done on five gas hydrate prediction methods based on the available experimental data. A model for the prediction of gas hydrate formation in deepwater oil and gas pipelines is established in combination with the Beggs Brill method. Besides, the relevant calculation program is thus prepared. Practical examples show that the hydrate formation region will be smaller when the circulation volume becomes greater, the thermal conductivity of the insulation material becomes smaller, the thickness of the insulating layer becomes greater, or the downtime becomes shorter. The model can be applied to decide a reasonable flow rate, choose the pipe heat insulation materials, and accurately calculate the non contact time. It provides technical support for the safe production of deepwater oil and gas fields.