多孔介质中甲烷水合物降压分解的LBM模拟  

LBM simulation of decompression decomposition of methane hydrate in porous medium

作　　者：吉梦霞 梁海峰[1] 张强 杨琨 JI Meng-xia;LIANG Hai-feng;ZHANG Qiang;YANG Kun(School of Chemistry and Chemical Engineering,Taiyuan University of Technology,Taiyuan 030024,Shanxi,China)

机构地区：[1]太原理工大学化学化工学院,山西太原030024

出　　处：《天然气化工—C1化学与化工》2020年第6期82-87,130,共7页Natural Gas Chemical Industry

基　　金：国家自然科学青年基金资助项目(编号:51106104)。

摘　　要：甲烷水合物藏的分解过程与多孔介质骨架结构及自身赋存状态等因素有关。采用格子Boltzmann方法(Lattice Boltzmann Method,LBM)的Shan-Chen模型模拟多组分多相流动,采用Kim-Bishnoi模型描述水合物分解反应,并结合VOP方法表示水合物分解的固-液-气转变,模拟了孔隙率、骨架结构以及水合物的赋存状态对多孔介质中甲烷水合物分解特性的影响,通过达姆科勒数(Da)表征分析控制机理。研究发现:水合物分解过程是先由传质扩散控制、后传质和化学反应相当、最后为反应控制的过程;多孔介质孔隙率大、迂曲度小、水合物处于包裹状态更有利于水合物分解,且孔隙率小于50%时降压分解不具有显著优势,应考虑降压注热联合开采。The decomposition process of methane hydrate reservoirs is related to the factors such as the skeleton structure of the porous medium and its own occurrence state.The Shan-Chen model of the lattice Boltzmann method was used to simulate multi-component multi-phase flow,the Kim-Bishnoi model was used to describe the hydrate decomposition reaction,and the VOP method was used to represent the solid-liquid-gas transition of hydrate decomposition.The effects of porosity,skeleton structure and hydration occurrence state on the decomposition characteristics of methane hydrate in the porous medium were simulated.The decomposition control mechanism was characterized by the Damcole number(Da).The research found that the hydrate decomposition process was controlled by mass transfer and diffusion,followed by mass transfer and chemical reaction,and then by reaction.The porous medium has large porosity and small tortuosity,and the hydrate is in a wrapped state,which are more conducive to hydrate decomposition.The decompression decomposition has no significant advantages when the porosity is less than 50%,thus the combined mining of decompression and heat in jection should be considered.

关 键 词：甲烷水合物 降压开采 格子Boltzmann方法 多孔介质 控制机理 产气特性 达姆科勒数 

分 类 号：TE31[石油与天然气工程—油气田开发工程]