摘要
我国页岩、致密油气等非常规油气的储量极大,非常规油气的开发对保障国家能源安全有重要的意义.准确模拟预测非常规油气的流动行为是经济高效开采的关键.不同于常规油气,页岩气在地层中存在滑脱效应以及吸附现象,为准确描述此类机理和现象,本文在以非结构PEBI网格为主的混合网格的基础上建立了组分数值模型,并对气体组分比例、吸附作用以及滑脱效应对产能的影响进行了分析.同时,对国内某页岩气藏水平井的压裂进行了优化.结果表明,页岩气产量随裂缝数量的增多以及裂缝半长的增长而增加,但当裂缝数量达到一定数量,裂缝半长达到一定长度时,产量的增加不再明显.因此,为使页岩气的经济效益达到最大化,应合理布置裂缝数量及裂缝半长.
The reserves of unconventional gas,such as shale and tight gas,is enormous in China.The exploitation of unconventional gas is of significance to secure our nation＇s energy future.Precise simulation and prediction of gas flowing behavior in such formations is the key to economic efficiency of exploitation.Different from conventional formations,in shale exist slip flow and gas adsorption.To accurately simulate gas flow in shale,we developed a compositional model based on the hybrid grid which is mainly composed by unstructured PEBI（Perpendicular Bisection） grids.Upon this model,the effects of gas composition,adsorption and slip flow on gas production are analyzed.Horizontal well fracturing in a shale gas reservoir is optimized with the help of this model.The results show that the production of shale gas increases rapidly with the number and effective half-length of fractures,and reaches a plateau when they get large or long enough.Therefore,in order to achieve the maximum economic efficiency,the fracture quantity and effective half-length should be reasonably designed.
出处
《科学通报》
EI
CAS
CSCD
北大核心
2016年第1期94-101,共8页
Chinese Science Bulletin
基金
中国石油天然气集团公司-中国科学院战略合作项目(2015A-4812)
中国科学院战略性先导科技专项(XDB10030402)
国家重大科技专项(2011ZX05009-006)资助
关键词
页岩气
组分模型
产能预测
压裂优化
滑脱效应
吸附作用
shale gas
compositional model
productivity prediction
fracturing optimization
slip flow
gas adsorption
