氮气泡沫吞吐控抑断块油藏边水效果

Nitrogen Foam Huff-n-Puff Preventing Edge-water Coning for Fault-block Reservoir

付忠凤 赵凤兰侯吉瑞 王 鹏 张 蒙 郝宏达 鲁国用

FU Zhongfeng ZHAO Fenglan HOU Jirui WANG Peng ZHANG Meng HAO Hongda LU Gouyong

存在边水的复杂断块油藏， 开发过程中由于边水不均匀推进， 导致水淹程度严重不均， 严重影响开发效果。通过建立相应的实验模型， 对比氮气吞吐、 起泡剂+稳泡剂吞吐的物理实施效果， 分析了氮气泡沫控抑边水效果的影响因素、 优化了注采参数， 并简要探讨了其控水增油机理。结果表明： 氮气泡沫吞吐发挥了起泡剂+稳泡剂和氮气 “1+1大于 2” 的效果， 其驱油效率比水驱开采阶段提高了 6.12%， 含水率最大下降幅度达到 21.81%； 氮气泡沫吞吐在非均质储层和低黏原油条件下控抑边水效果更佳； 在边水能量较弱（折算泵度 0.5 mL/min）情况下， 氮气泡沫吞吐控抑边水效果更好； 在边水能量较强 （折算泵度 2.5 mL/min） 的情况下， 选择泡沫注入量 0.1 PV、闷井时间 24 h、 注入时机在含水 85%～98%范围内能使氮气泡沫吞吐控抑边水取得更好的效果。图3表 6参 22

In process of exploring the complex fault-block reservoir with edge water， water coning problem will be more and more serious， which will lead to excessive water production and reduce the oil production. A related experimental model was developed to evaluate the effectiveness of nitrogen foam preventing edge water coning in huff-n-puff wells by comparing with that of single nitrogen system and surfactant-polymer system. The model also was used to analyze the effect factor， optimize injection parameters of nitrogen foam and study on its mechanism. The results showed that the nitrogen foam was not only combined with both advantages of nitrogen and surfactant-polymer， but also had its own superiority in preventing edge water coning in puff and huff wells， the huff-n-puff wells’oil displacement efficiency increased by 6.12%， and the water cut decreased by 21.81% after nitrogen foam stimulating. Moreover，the ability of nitrogen foam to inhibition edge water coning would gain an ideal result with heterogeneous reservoir and low viscosity oil. When the edge water was insufficient， conversed in pump’ s velocity 0.5 mL/min， the application of nitrogen foam would be more successful in controlling edge water coning as edge water force weakening. When the edge water is more adequate， conversed in pump’ s velocity 2.5 mL/min， with the volume of injecting foam selected 0.1 PV and the option of soaking time chosen 24 h， the stimulation of nitrogen foam in huff-n-puff wells would be more effective in preventing edge water and achieve more profit margin.

10.19346/j.cnki.1000-4092.2018.01.019