脉动微波循环注热开采煤层气数值模拟  

Numerical Simulation of Coalbed Methane Extraction by Pulsation Cycle Microwave Heat Injection

作　　者：杨新乐[1] 姜涛 苏畅[1] 李惟慷[1] 张永利[2] YANG Xin-le;JIANG Tao;SU Chang;LI Wei-kang;ZHANG Yong-li(School of Mechanical Engineering,Liaoning Technical University,Fuxin 123000,China;School of Mechanics and Engineerings Liaoning Technical University,Fuxin 123000,China)

机构地区：[1]辽宁工程技术大学机械工程学院,阜新123000 [2]辽宁工程技术大学力学与工程学院,阜新123000

出　　处：《微波学报》2021年第4期89-94,共6页Journal of Microwaves

基　　金：国家自然科学基金(51574136,51574138,51104083);辽宁省“兴辽英才计划”(XLYC1807150)。

摘　　要：为获取脉动微波循环加热条件下低渗透储层煤层气运移采出规律,文中综合运用多孔介质传热学、电磁学、渗流力学、岩石力学等相关理论,建立低渗透储层煤层气微波注热开采过程渗流电磁-热-流-固多物理场耦合数学模型,结合COMSOL Multiphysics有限元分析软件进行了脉动微波循环加热过程煤层气运移采出规律的数值模拟,获取了不同功率脉动微波循环加热条件下煤层温度场、渗流场的变化规律,并对煤层气产量进行了预测。数值模拟结果表明:脉动微波循环加热煤储层热效应显著,煤层能快速且不断地处于高温状态,气体在高温条件下大量解吸并运移产出。采用脉动循环加热,将继续增加煤层渗透率和煤层中游离煤层气含量,相对于常规开采,煤层含气量大幅度降低,煤层气产量显著提高,增产与稳产交替变换使产量在长时期内处于增产状态。模拟方法与结果可为低渗透储层煤层气脉动微波加热开采技术方案提供理论依据。In order to obtain the rule of migration and production of coalbed methane(CBM)in low permeability reservoirs under pulsation cycle microwave heat injection,combined with porous media heat transfer,electromagnetism,seepage mechanics,rock mechanics and so on,the coupled mathematical model of electromagnetic-thermal-fluid-solid multiple physical fields in low permeability reservoir is established,combined with COMSOL Multiphysics finite element analysis software,the numerical simulation of CBM migration and production law during pulsation cycle microwave heating is carried out,the variation rules of temperature field and seepage field of coal seam under different power microwave heating conditions is obtained and CBM production is predicted.Numerical simulation results show that the pulsation cycle microwave heating coal reservoir thermal effect is significant,the coal seam can be at high temperature rapidly and constantly,under high temperature conditions,a large number of gas desorpts and produces.The adoption of pulsation cycle heating can continuously increase the permeability of coal seam and the content of free coalbed methane in coal seam,compared with conventional mining,the coal seam gas content is significantly reduced and production is significantly increased,the increased and stable production alternates so that CBM production is increased over a long period of time.The simulation methods and results can provide a theoretical basis for the pulsation cycle microwave heat injection mining of CBM in low permeability reservoirs.

关 键 词：煤层气 微波注热 脉动循环 电磁-热-流-固耦合 数值模拟 

分 类 号：TE37[石油与天然气工程—油气田开发工程]