摘要
断块油藏单口水平井CO_2吞吐过程中,井组内其它生产井油量增加,呈现出一定协同效应,但相关机理和影响因素不够明确。针对上述问题,本研究依据实际油藏条件,建立可模拟边水作用和地层倾角的断块油藏水平井组三维物理模型,进行水平井CO_2协同吞吐实验,并评价断块油藏不同构造部位控水增油效果,优化水平井注气吞吐部位。实验结果表明,低部位井注入CO_2吞吐的条件下,低、中、高3个部位生产井的吞吐采出程度分别增加6.59%、5.76%和4.98%,水平井井组CO_2吞吐具有明显的协同增油效果。相同实验条件下,高部位井注气吞吐起到气顶作用,中、低部位井含水率降低不明显,边水的抑制效果不明显,井组增油量低,气体利用率最低;中部位井注气吞吐控水增油效果介于二者之间。因此,建议从油藏构造低部位的水平井注气,以充分发挥其协同增油和控抑边水作用。
Aquifers in the vicinity of a reservoir give rise to water coning and channeling.A high water cut constrains the effective production of horizontal wells in fault-block reservoirs.Previous field cases demonstrate favorable results of CO_2 huff and puff in reducing water cut and increasing oil production.In this study,a 3 D fault-block reservoir model is built similar to the actual reservoir conditions,considering the existence of side water and the reservoir dip.Three experiments are implemented to study the effect of structural position on the synergistic effects of CO_2 huff and puff in horizontal wells.Synergistic results are observed when gas is injected into one horizontal well,and the other two horizontal wells see a drop in water cut and a rise of oil production.Gas injected into the low geological position achieves the highest total oil recovery increase（6.6% in the low position,5.8% in the middle and 5.0% in the high position） and the most efficient gas utilization（1.73）.With the same volume of gas,the lower the position where the gas is injected,the more significant the water suppression and oil increase.In order to obtain higher oil stimulus and water drop,the candidate well for CO_2 huff and puff should be in the lowest geological position.
作者
王志兴
赵凤兰
侯吉瑞
郝宏达
WANG Zhixing;ZHAO Fenglan;HOU Jirui;HAO Hongda(Research Institute of Enhanced Oil Recovery,China University ofPetroleum-Beijing,Beijing 102249,China;Key Laboratory of Petroleum Engineering of Education Ministry,Beijing 102249,China;Key Laboratory of Beijing City on Greenhouse Gas Storage for Recovering Oil,Beijing 102249,China)
出处
《石油科学通报》
2018年第2期183-194,共12页
Petroleum Science Bulletin
基金
国家科技重大专项"低渗-致密油藏高效提高采收率新技术"(2017ZX05009-004)资助
关键词
断块油藏
水平井CO2吞吐
注气部位
协同作用
reservoir with side water
horizontal well CO2 huff and puff
structural position
synergistic effect
