【作者】 马天态；

【导师】 李兆敏；

【作者基本信息】 中国石油大学 ， 油气田开发工程， 2007， 硕士

【摘要】 底水油藏在国内外油田中普遍存在,人工夹层、采水消锥等技术在底水油藏开采中都有一定的局限性,应用效果不理想。氮气是一种非凝析气体,压缩系数高,膨胀性强,进入地层后,能及时补充地层能量,增加地层压力。氮气泡沫流体在地层中具有较高的稳定性,流动阻力与水相比大幅提高,可用于封堵水窜通道,氮气泡沫流体压水锥技术具有很高的研究推广价值。本文采用理论、实验和数值模拟方法,开展了相应的研究工作,主要包括三部分内容:一是氮气泡沫在多孔介质中的稳定性研究,氮气泡沫的稳定性是压水锥的关键,研究结果表明,氮气泡沫在多孔介质中具有良好的稳定性,封堵性能强,在岩心管中封闭保存90天后注水时封堵率为91.7%。二是氮气泡沫压水锥机理研究,推导了曲线水锥的体积表达式,作为氮气泡沫压水锥时泡沫注入量的参考。机理研究表明,在接近油水界面处,高压、大排量注入氮气泡沫可以弥补近井带压力亏空,压迫水锥下移,由于氮气的弹性能量、气泡的贾敏效应以及氮气泡沫的选择性封堵作用,氮气泡沫可以有效地封堵底水上窜通道,减缓底水锥进。三是运用数值模拟方法,对氮气泡沫压水锥的注入时机、注入速度、注入量、关井时间、开井后生产液量、垂直/水平渗透率比值和夹层位置等敏感性因素进行计算分析,得出了以上因素影响氮气泡沫压水锥增油效果的规律。通过胜利乐安油田3口热采井的现场试验结果可知,压水锥以后,产油量和上一周期相比有较大幅度增加,含水率降低或保持平稳,氮气泡沫压水锥降水增油效果明显。更多还原

【Abstract】 There is bottom water reservoir in the oil field of every country. Thetechnology of artificial interbed and recovering water to remove the waterconing is restricted with unideal effect. The nitrogen can supply theproducing energyand increase the reservoir pressure with its non-condensatehigh compressibility and dilatabilityafter its entering into the formation. Thenitrogen foam can be used to seal the channel with its high stabilityand highflow resistance compared to water, so the technology is worth to study andintroduce.The research was done using theory, experiment and numericalsimulation including three parts: one is the study on the stability of nitrogenfoam in porous media, and it is critical to the pushing. It demonstrated thatthe stabilityand sealing characteristics are good and ratio of sealingis 91.7%after canningin thebarrel for90days. Thesecond is thestudyof mechanismfor the pushing. The volume expression was derived as the reference for thevolume of injecting while pushing the water by nitrogen foam. It indicatesthatthenitrogenfoam couldretrievepressuredepletionofimmediatevicinityofwellboreandrepressthewaterconingwithhighpressureanddisplacementneartheoil/water interface. It also couldseal offthechannel of bottom waterand slow down the coning as a result of the elastic energy of nitrogen and Jamin action of foam and the selective blockage of nitrogen foam. The thirdis the computational analysis of sensible factor using numerical simulation,including the injecting time, velocity and volume, the close time, the liquidproducing capacity after opening the well, the ratio between verticalpermeability and horizontal permeability and the position of interbed etc. Allthe law of the effect of increasing oil using nitrogen foam to push the waterconingwasobtainedinthispaper.By means of site test in the three thermal wells in Shengli Le-an field,it could be known that the crude output increased significantly compared tothe last production cycle, water ratio decreased or keep stability and therewas a good effect of decreasing the water and increasing the oil by pushingwatercorningwithnitrogenfoam.更多还原