甲烷水合物降压结合注热分解实验研究  

Experimental study of methane hydrate dissociation by depressurization combined with heat injection

作　　者：李孝艳 周诗岽[1] 李恩田[1] LI Xiaoyan;ZHOU Shidong;LI Entian(School of Petroleum and Natural Gas Engineering,Changzhou University,Changzhou 213164,China)

机构地区：[1]常州大学石油与天然气工程学院,江苏常州213164

出　　处：《常州大学学报(自然科学版)》2025年第2期62-72,共11页Journal of Changzhou University:Natural Science Edition

基　　金：国家自然科学基金青年基金资助项目(52206231)。

摘　　要：水合物沉积层类型包括砂质型、黏土型及泥质粉砂型,不同类型沉积层中多孔介质粒径分布范围不同。为明确多孔介质粒径对水合物注热分解过程中热质传递特性的影响,本文在不同粒径石英砂中进行了甲烷水合物降压结合注热分解实验,基于水合物分解过程的温度、压力、产气、产水,分析了不同注热周期下水合物分解特性、注入热水的有效影响区域及气水流动特性,探讨了不同粒径石英砂中水合物注热分解速率差异的内在机制。研究表明,在不同粒径的石英砂中,注入热水对沉积层热质传递的相对影响大小存在区别。在粒径较小的石英砂中,注入热水对沉积层传热的有利影响大于不利影响;而在粒径较大的石英砂中,注入热水对沉积层传质的不利影响大于有利影响,导致水合物分解速率随石英砂粒径的减小呈现先降低后增加的趋势。该研究可为实际不同粒径沉积层中天然气水合物开采方法的优选提供理论指导。The kinds of gas hydrate reservoir include the sandy sediments,the clay sediments,and the silty-clay sediments.The particle size distribution of porous media in different kinds of hydrate reservoir are various.To understand the influences of the injected hot water on the heat and mass transfer rate during hydrate dissociation,the experiments of hydrate dissociation by depressurization combined with hot water injection in the quartz sand with different particle sizes were conducted in this paper.According to the change of the temperature,the pressure,the gas production,and the water production during hydrate dissociation,the hydrate dissociation behavior,the effective affecting region of the injected hot water and the flow behavior of gas-liquid in the sediments at different cycles of heat injection were analyzed.Meanwhile,the reasons for the different hydrate dissociation rates in the quartz sand with different particle sizes were discussed.The results indicated that,in the sediments with different particle sizes,the relative influences of the injected hot water on the heat and mass transfer rate of the sediments were various.In the quartz sand with smaller particle size,the advantageous influences of the injected hot water on the heat conduction were higher than the adverse influences of the injected hot water on the mass transfer.However,in the quartz sand with larger particle size,the advantageous influences of the injected hot water on the heat conduction were lower than the adverse influences of the injected hot water on the mass transfer.As a result,the hydrate dissociation rate first reduced then increased with the reduction of the particle size of the quartz sand.This study could provide guidance for choosing a suitable method for gas hydrate production from actual reservoirs.

关 键 词：甲烷水合物 降压结合注热法 石英砂 粒径 热质传递 

分 类 号：TE3[石油与天然气工程—油气田开发工程]