第29卷第5期 2015年10月
现代地质 GEOSCIENCE
松散沉积物中水合物降压分解阵面
演化实验及数值模拟刘乐乐，孙建业，刘昌岭，业渝光
（1.国土资源部天然气水合物重点实验室青岛海洋地质研究所，山东青岛266071）
Vol.29No.5
Oct.2015
摘要：水合物分解阵面是水合物开采现场监测关注重点之一，其传播速率与水合物开采效率密切相关，但是目前松散沉积物中水合物降压分解阵面演化数据积累明显不足。进行了松散沉积物中水合物降压分解阵面演化实验，采用时域反射技术测量了水合物饱和度随时间的变化，分析了水合物分解阵面的传播规律；提出了轴对称水合物降压分解数学模型并进行了适用性验证，通过敏感性分析探讨了影响因素对水合物分解阵面演化过程的影响关系。基于室内实验和数值模拟认为：（1)水合物降压分解阵面传播距离与其传播时间平方根呈近似线性关系；（2）水合物降压分解阵面传播速率随其传播距离的增加而迅速减小；（3)水合物降压分解阵面传播速率随着绝对渗透率基准值、气体饱和度初始值和
环境温度的增加而增大，随着水合物饱和度初始值、下降指数和出口压力的增加而减小。关键词：含水合物沉积物；降压法；分解阵面；时域反射技术；敏感性分析
中图分类号：P744.4
文献标志码：A
文章编号：10008527(2015)05123408
Experimental and Numerical Study on the Hydrate DissociationFront
InducedbyDepressurizationinUnconsolidatedSediment
LIU Le-le,SUN Jian-ye, LIU Chang-ling,YE Yu-guang
( Key Laboratory of Gas Hydrate, Ministry of Land and Resourees, Qingdao Institute of Marine Geology, Qingdao, Shandong 266071, China) Abstract : Hydrate dissociation front is one of objects of the field monitoring during gas hydrate production, and its velocity is closely related to the efficiency of gas hydrate production. However, there are few literatures about experimental data of the hydrate dissociation front. In view of this, an experiment of hydrate dissociation front induced by depressurization in unconsolidated sediment was developed. The hydrate saturation was measured by the time domain reflection measurement, and the movement of hydrate dissociation front was analyzed. An axi-symmetric model for hydrate dissociation was proposed and its applicability was performed. A sensibility analysis for the velocity of hydrate dissociation front was carried out.Based on the experimental and numerical condi-tions, main conclusions were made as follows : first, propagation distance of hydrate dissociation front is approxi-matively linear with the square root of propagation time; second, velocity of the hydrate dissociation front de creases obviously when the propagation distance becomes longer; finally, velocity of the hydrate dissociation front increases when the reference value of the absolute permeability, initial gas saturation, and environmental temperature increase, however, it decreases when the initial hydrate saturation, reduction index, and outlet pressureincrease
Key words: hydrate-bearing sediment; depressurization; hydrate dissociation front; time domain reflection ; sensibility analysis
收稿日期：2015-03-19；改回日期：2015-07-30；责任编辑：或开静。
（0）国
化碳在甲烷水合物沉积层中垂向扩散机制研究（41306065）。
作者简介：刘乐乐，男，博士，助理研究员，1986年出生，工程力学专业，主要从事天然气水合物开采涉及的力学问题研究，
Email : liulele_leo@163. com。