塔河缝洞型油藏井组氮气驱影响因素分析

Influencing factors for nitrogen flooding in fractured-vuggy reservoir well groups in Tahe oil field

解慧 郭臣 陈勇

Xie Hui Guo Chen Chen Yong

中国石化 西北油田分公司 勘探开发研究院, 乌鲁木齐 830011

Research Institute of Exploration & Production, SINOPEC Northwest Company, Urumqi, Xinjiang 830011, China

氮气驱三次采油技术在塔河油田应用广泛，增油效果显著，但井组氮气驱效果差异大，影响因素尚不明确。基于对缝洞型油藏的认识，将岩溶背景划分为风化壳+暗河复合岩溶、暗河岩溶和断溶体3大类型，研究不同岩溶背景下的储集体深度、剩余地质储量和注入气水比对井组注氮气增油效果的影响。从已完成评价的35个注气井组出发，分析不同岩溶背景下的注气效果影响因素，从而进一步指导油田的注气工作。

At present, nitrogen flooding technique is widely used in the Tahe oil field, leading to significant oil increment. However, the effect of nitrogen flooding in well groups is different, and the influencing factors are not clear. The karst background was divided into three types, including weathered crust+subsurface stream composite karst, subsurface stream karst and broken solution karst, based on the understanding of fractured-vuggy reservoirs. The influences of reservoir depth, remaining geological reserves and injected gas-water ratio on the effect of nitrogen injection in well groups were studied. The influencing factors of nitrogen injection effect under different karst backgrounds were analyzed from 35 injection well groups that had completed evaluation, so as to guide nitrogen injection works in oil fields in the future.

https://doi.org/10.11781/sysydz2017S1023