低渗透储层中氮气的微尺度流动及其对渗流的影响  

Micro-scale flow effect of nitrogen in low-permeability reservoir and its influence on gas seepage

作　　者：王斐[1] 岳湘安[2] 庞宏伟[3] 王雯靓[4] 

机构地区：[1]川庆钻探工程有限公司地质勘探开发研究院,四川成都610051 [2]中国石油大学(北京)石油工程教育部重点实验室,北京102249 [3]中国石油天然气集团公司伊朗公司,北京100011 [4]川庆钻探工程有限公司川西钻探公司,四川成都610000

出　　处：《西安石油大学学报（自然科学版）》2012年第1期57-59,120,共3页Journal of Xi’an Shiyou University（Natural Science Edition）

基　　金：国家973计划项目"温室气体提高石油采收率的资源化利用及地下埋存"子课题:CO2驱替过程中多相多组分非线性渗流机理和规律(编号:2006CB705805)

摘　　要：从气体在低渗透储层微米量级孔喉中的微尺度流动规律研究入手,探讨低渗透储层中气体的非线性渗流机理.实验研究了气体(N2)在内径为2.05～10.10μm微管中的流动规律.结果表明:气体在微管中的流动具有明显的微尺度效应,表现为实测流量大于经典流体力学理论预测流量;管径越小,流动压力越小,微尺度流动效应越强,实测流量与预测流量的偏离越显著.根据微管实验数据,结合毛管束模型,研究了气体微尺度流动效应对渗流的影响.结果表明:考虑孔喉中气体的微尺度流动效应后,低渗透多孔介质中气体的渗流具有非线性特征,表现为视渗透率随流动压力的减小而增加;多孔介质平均孔喉直径越小,视渗透率随压力的变化越明显.The nonlinear seepage mechanism of gas in low-permeability reservoir is discussed by studying the micro-scale effect of gas flowing through the micro-sized pores in low-permeability reservoirs.The flow characteristics of gas(N2) in the micro-tubes of the diameter of 2.05~10.1μm are experimentally investigated.The results indicate that,the real flow rate in experiments is always greater than that predicted by the classic fluid mechanics theory,which is called as the micro-scale flow effect of gas,and that,the less the diameter of the micro-tubes and the flow pressure,the stronger the micro-scale flow effect of gas,or the greater the difference between the real flow rate and the predicted flow rate.The influence of the micro-scale flow effect on the seepage of gas in low-permeability reservoir was studied based on the micro-tube experiment data and capillary bundle model.It is shown that,the seepage of gas in low-permeability porous media is nonlinear when the micro-scale flow effect of gas is considered.The apparent permeability of gas in low-permeability reservoir increases with the decrease of gas flow pressure,which becomes more obvious when the mean diameter of pores and throats in the porous media becomes small.

关 键 词：低渗透储层 气体渗流 非线性渗流 微尺度流动 毛管束模型 

分 类 号：TE311[石油与天然气工程—油气田开发工程]