致密砂岩气藏井网加密优化  

Optimization of well pattern infilling in tight sandstone gas reservoir

作　　者：胡勇[1] 梅青燕 王继平[3] 陈颖莉[2] 徐轩[1] 焦春艳[1] 郭长敏[1] HU Yong;MEI Qing-yan;WANG Ji-ping;CHEN Ying-li;XU Xuan;JIAO Chun-yan;GUO Chang-min(PetroChina Research Institute of Exploration&Development,Beijing 100083,China;PetroChina Southwest Oil&Gafield Company,Chengdu 610051,China;PetroChina Changqing Oil Field Company,Xi’an 710018,China)

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]中国石油西南油气田分公司,四川成都610051 [3]中国石油长庆油田分公司,陕西西安710018

出　　处：《天然气地球科学》2020年第9期1326-1333,共8页Natural Gas Geoscience

基　　金：国家自然科学基金青年基金“致密砂岩微纳米孔喉系统对储层含气性及气水运移的控制机理”(编号:51704326)资助。

摘　　要：采用物理模拟实验与数学评价方法相结合,系统研究了井控范围从500 m逐步加密至100 m(相当于井距从1000 m加密至200 m)过程中不同渗透率砂岩储层在不同含水饱和度条件时的储量采出程度,揭示了井网加密对提高储量采出程度作用,以采出程度提高5%~10%和大于10%为依据,建立井网加密可行性判识图表,为气藏井网部署和加密方案优化提供了参考依据。实验岩心常规空气渗透率分别为1.63×10^-3μm^2、0.58×10^-3μm^2、0.175×10^-3μm^2、0.063×10^-3μm^2,含水饱和度介于30.3%~71.1%之间。研究结果表明:渗透率为1.63×10^-3μm^2的储层,采出程度总体均较高,除了在含水饱和度高达69.9%时的采出程度与井控范围有关外,其余含水饱和度条件下,采出程度与井控范围关系不大,可以采用大井距开发;渗透率为0.58×10^-3μm^2的储层,采出程度与含水饱和度和井控范围关系密切,随含水饱和度降低、井控范围加密而增加;渗透率为0.175×10^-3μm^2的储层,采出程度受含水饱和度的影响十分显著,只有在含水饱和度≤52.3%时,井网加密优化可提高储量采出程度,当含水饱和度>52.3%时,储量采出程度均较低,一般≤10%,即使井控范围加密至100 m,也难以得到提高;渗透率为0.063×10^-3μm^2的储层,总体上采出程度非常低,即使含水饱和度仅有31.6%,井控范围加密至100 m,其采出程度最高也只有2.3%,因此,该类储层依靠井网加密难以得到有效动用。The reserve producing degree of sandstone reservoirs with different permeability under different water saturation conditions has been systematically studied by combining physical simulation experiment with mathe-matical evaluation method during well control range from 500 m to 100 m(the equivalent of well spacing from 1000 m to 200 m).This paper reveals the effect of well pattern infilling on increasing reserve producing degree,and the chart for identifying the feasibility of well pattern infilling has been established based on the increase of the recovery degree by 5%-10%and more than 10%,which provides a reference for the well pattern disposetion and infilling scheme optimization of gas reservoirs.The core with conventional air permeability of 1.63×10^-3μm^2,0.58×10^-3μm^2,0.175×10^-3μm^2 and 0.063×10^-3μm^2 and the water saturation between 30.3%and 71.1%has been used in the experiments.The results show that the reservoir with permeability of 1.63×10^-3μm^2 has a high degree of production.Except when the water saturation is as high as 69.9%,the production degree is related to the well control range,the production degree has little relation with well control range,and it can be developed with large well spacing.For reservoirs with permeability of 0.58×10^-3μm^2,the degree of production is closely related to water saturation and well control range,and it increases with the decrease of water saturation and the densification of well control range.For reservoirs with permeability of 0.175×10^-3μm^2,only when the water saturation is less than or equal to 52.3%,well pattern infilling optimization can improve the degree of reserve production,and when the water saturation is more than 52.3%,the degree of reserve production is low,usually less than or equal to 10%.Even if the well control range is encrypted to 100m,it is difficult to improve.For the reservoir with a permeability of 0.063×10^-3μm^2,it has a very low degree of production as a whole,even if the water saturation is only 31.6%and the well cont

关 键 词：致密砂岩气藏 井网加密 储量动用 物理模拟 开发优化 

分 类 号：TE357[石油与天然气工程—油气田开发工程]