物理化学学报 >> 2009, Vol. 25 >> Issue (03): 486-494.doi: 10.3866/PKU.WHXB20090315

研究论文 上一篇    下一篇

热力学抑制剂作用下甲烷水合物分解过程的分子动力学模拟

万丽华 颜克凤 李小森 樊栓狮   

  1. 中国科学院广州能源研究所, 广州天然气水合物中心, 广州 510640; 中国科学院研究生院, 北京 100049; 中国科学院可再生能源与天然气水合物重点实验室, 广州 510640; 华南理工大学传热强化与过程节能教育部重点实验室, 广州 510640
  • 收稿日期:2008-09-24 修回日期:2008-12-02 发布日期:2009-03-02
  • 通讯作者: 李小森 E-mail:lixs@ms.giec.ac.cn

Molecular Dynamics Simulation of Methane Hydrate Dissociation Process in the Presence of Thermodynamic Inhibitor

 WAN Li-Hua, YA Ke-Feng, LI Xiao-Sen, FAN Shuan-Shi   

  1. Center for Gas Hydrate Research, the Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, P. R. China; Graduate University of Chinese Academy of Sciences, Beijing 100049, P. R. China; 3Key Laboratory of Renewable Energy and Gas Hydrate, Chinese Academy of Sciences, Guangzhou 510640, P. R. China; 4Key Laboratory of Enhanced Heat Transfer and Energy Conservation of the Ministry of Education, South China University of Technology, Guangzhou 510640, P. R. China
  • Received:2008-09-24 Revised:2008-12-02 Published:2009-03-02
  • Contact: LI Xiao-Sen E-mail:lixs@ms.giec.ac.cn

摘要:

采用正则系综(NVT)分子动力学方法模拟研究277.0 K、11.45 mol·L-1的热力学抑制剂乙二醇(EG)溶液作用下甲烷水合物分解微观过程. 模拟显示甲烷水合物的分解从甲烷水合物固体表面开始, 逐渐向内部推移, 固态水合物在分解过程中逐渐缩小, 直至消失. 固态水合物的分解从晶格扭曲变形开始, 之后笼形框架结构破裂, 最后形成笼形结构碎片. 同时已经分解的甲烷水合物在外层形成水膜, 包裹里层正在分解的甲烷水合物, 增大里层甲烷水合物分解传质阻力.

关键词: 甲烷水合物, 分子动力学, 乙二醇溶液, 分解

Abstract:

The dissociation of methane hydrate in the presence of ethylene glycol (11.45 mol·L-1) at 277.0 K was studied using canonical ensemble (NVT) molecular dynamics simulations. Results show that hydrate dissociation starts from the surface layer of the solid hydrate and then gradually expands to the internal layer. Thus, the solid structure gradually shrinks until it disappears. A distortion of the hydrate lattice structure occurs first and then the hydrate evolves from a fractured frame to a fractional fragment. Finally, water molecules in the hydrate construction exist in the liquid state. The inner dissociating layer is, additionally, coated by a liquid film formed from outer dissociated water molecules outside. This film inhibits the mass transfer performance of the inner molecules during the hydrate dissociation process.

Key words: Gas hydrate, Molecular dynamics, Ethylene glycol solution, Dissociation

MSC2000: 

  • O641