西南石油大学学报(自然科学版)

• 石油与天然气工程 • 上一篇    下一篇

天然气水合物分解超孔隙压力研究

张炜1,2 *,李新仲1,李清平1,曹静1   

  1. 1. 中海油研究总院,北京朝阳100028
    2. 中国科学院力学研究所博士后流动站,北京海淀100190
  • 出版日期:2015-08-01 发布日期:2015-08-01
  • 通讯作者: 张炜,E-mail:zhangwei28@cnooc.com.cn
  • 基金资助:

    国家重点基础研究发展计划(973 计划)(2009CB219507);国家科技重大专项(2011ZX05026 004;2011ZX05056 002)。

Study on Excess Pore Pressure by Natural Gas Hydrate Dissociation

Zhang Wei1,2*, Li Xinzhong1, Li Qingping1, Cao Jing1   

  1. 1. General Research Institute,China National Offshore Oil Corporation,Chaoyang,Beijing 100028,China
    2. Postdoctoral General of Institute of Mechanics,Chinese Academy of Sciences,Haidian,Beijing 100190,China
  • Online:2015-08-01 Published:2015-08-01

摘要:

针对海洋油气资源开采和海洋工程施工过程中天然气水合物分解所引发的工程风险问题,展开了天然气水合
物分解超孔隙压力理论模型研究。研究中采用理论解析方法,基于水合物分解前后的相态模型和热力学中的通用气
体定律,推导了水合物分解导致的沉积物体积膨胀模型,进一步采用土力学中土体的压缩和回弹特性,最终获得了水
合物分解超孔隙压力理论解析模型。采用典型的海底滑坡工程案例,验证了模型的合理性与正确性,并针对模型中复
杂的影响参数展开参数考察,获得了不同参数的影响效应。研究对认识水合物分解产生的超孔隙压力的演变机理,保
证水合物的储层稳定性,规避水合物分解带来的工程灾害具有重要的理论价值和现实意义。

关键词: 天然气水合物, 水合物分解, 体积膨胀模型, 超孔隙压力模型, 参数考察

Abstract:

For the engineering risk caused by natural gas hydrate dissociation during the offshore hydrocarbon resource exploitation
and ocean engineering construction processes,a theoretical model is proposed for the analysis of excess pore pressure
due to the gas hydrate dissociation. The theoretical-analytical method is adopted in the study. Firstly,based on the phase behavior
models before and after the hydrate dissociation and the general gas law in thermodynamics,the volume expansion model
of sediments caused by the hydrate dissociation is derived,and then,according to the soil compression and swelling behavior
in soil mechanics,the theoretical-analytical model is obtained for the analysis of excess pore pressure by the hydrate dissociation.
The reasonability and validity of the model have been verified by the representative submarine landslide case. Besides,a
parametric analysis has been performed to investigate the complex affecting parameters in the model. This study is of important
theoretical value and practical significance to understand the evolution mechanism of the excess pore pressure resulting from
the hydrate dissociation,ensure the hydrate reservoir stability and avoid the project risk.

Key words: natural gas hydrate, hydrate dissociation, volume expansion model, excess pore pressure model, parametric
analysis