摘要
油藏经过聚驱后,还有相当数量的石油残留在地层中成为剩余油,经过聚合物溶液驱过的油藏,剩余油在微观孔隙中的分布更加分散,这对聚驱后剩余油挖潜措施提出更高的要求,剩余油在微观孔隙中的存在形态和分布特征是实施四次采油的主要因素,确定聚驱后剩余油分布的形态和分析影响聚驱效果的因素对聚驱后剩余油的挖潜具有重要的理论意义和实际应用价值。
本文以压汞实验得到的岩心的孔隙特征参数为依据建立三维孔隙网络模型,借助网络模型将孔隙的微观结构特征与微观渗流机理有机统一,模拟了饱和油、水驱油和聚合物溶液驱油过程,在模拟聚合物溶液驱油过程中主要考虑了聚合物溶液粘度的变化对驱油效果的影响,模拟出聚驱后剩余油的分布形态,分析了孔隙的结构参数与注入参数的变化对聚驱效果的影响,并以可视化仿真物理模型实验验证了模拟结果的正确性;网络模型模拟的结果表明:聚驱后孔隙中的剩余油趋于分散化,但仍以簇状油为主,与水驱后剩余油分布状态比较可以发现簇状油比例有所减少,孤滴状和柱状油的比例有所增加;平均半径较大的孔隙聚驱效果要好于平均半径较小的孔隙;孔隙的形状因子越大,说明孔道的截面形状越规则,越有利于提高驱油效率;孔隙的配位数越大,说明孔隙的连通通道越多,流动性越强,聚驱后剩余油百分含量越低;岩石的润湿性对聚驱的效果起主要作用,水湿岩心要比油湿岩心驱油效果要好;同样,聚合物溶液浓度的提高和驱替压力的加大都能增强聚合物溶液的驱油效果。
There is much residual oil remained in the oilfield after polymer flooding, within the area where is flooded by polymer in the oilfield, the residual oil is more decentralization, multiplicity and complexity, which is calling for higher request to the measure of residual oil digging after polymer flooding, it will be having important theoretical supports and application value for residual oil digging after polymer flooding to ascertain the features of residual oil distribution as well as it microscopic affecting factor are studied.
The paper was on the base of porosity parameters which is obtained by the pressing mercury experiment of the artificial core, the 3-D network models based on which will be built. By means of 3-D network model, the organic unity of reservoir rock pore structure parameters and the microscopic seepage mechanism are obtained, and simulation the process of oil saturated、first water flooding and polymer flooding. In the process of microscopic polymer flooding simulation, the variation of the viscosity of polymer is mostly considered. Calculating the distribution morphology of the residual oil and analyzing the affecting factor of polymer flooding, the validity is proved by visualization simulation modeling experiment. The result of 3-D network model simulation has show that compared with water flooding the residual oil is decentralization, and mostly of which arranged in the formed of fascicles, but the number of fascicles oil is decrease significantly, island shape and ventilation shape increased. The bigger of the average of the pore radius, the better of the effect of polymer flooding. With the increase of the shape factor, indicating the shape of pore section is more mellow, and it is more benefit to enhance oil recovery. With the increase of the coordination number, the more path pores have, the more smooth of the liquidity of pores, the less of the percentage composition of residual oil after polymer flooding, the wettability is very important to the effect of polymer flooding, the water wetting condition is better than the oil wetting condition. Enhancing the concentration of the polymer and pressure of injection is more availability to polymer flooding.
引文
[1]俞启泰.关于剩余油研究的探讨[J].石油勘探与开发,1997,(02).
[2]罗红芳.剩余油的形成与分布研究现状[J].延安职业技术学院学报,2009,(03).
[3]杨勇.剩余油分布规律影响因素分析研究[J].石油天然气学报,2009,(01).
[4]任峤.剩余油分布影响因素浅析[J].今日科苑,2008,(04).
[5]高博禹,彭仕宓,王建波.剩余油形成与分布的研究现状及发展趋势[J].特种油气藏,2004,(04).
[6]张昌维.剩余油分布规律研究综述[J].内江科技,2005,(01).
[7]刘宝珺,谢俊,张金亮.我国剩余油技术研究现状与进展[J].西北地质,2004,(04).
[8]冉启佑.剩余油研究现状与发展趋势[J].油气地质与采收率,2003,(05).
[9]李洪玺,刘全稳,温长云,张学才,刘婕.剩余油分布及其挖潜研究综述[J].特种油气藏,2006,(03).
[10]焦雪峰,陈明强,金维鸽.剩余油分布技术研究[J].新西部(下半月),2007,(04).
[11]李洁,谭艳宜.用岩心磨片荧光分析研究聚合物驱后剩余油微观分布——以大庆油田葡Ⅰ组为例[J].油气地质与采收率,2004,(06).
[12]李洁,隋新光,邵振波.大庆油田葡一组油层聚驱后剩余油微观分布规律研究[J].大庆石油地质与开发,2005,(02).
[13]张继成,李朦,穆文志,皮彦夫,宋考平.聚合物驱后宏观和微观剩余油分布规律[J].齐齐哈尔大学学报,2008,(01).
[14]宋考平,杨钊,舒志华,方伟.聚合物驱剩余油微观分布的影响因素[J].大庆石油学院学报,2004,(02).
[15]宋荣华,王军,何艳辉,王金友.荧光显微图像技术判断储层流体性质研究[J].油气井测试,2000,(04).
[16]孙尚如,何先华,邬侠,卢祥国.聚合物驱后剩余油分布核磁成像实验研究[J].大庆石油地质与开发,2003,(04).
[17]范文星.密闭取心井钻井技术及其问题探讨[J].石油天然气学报,2007,(02).
[18]辛治国,冯伟光.利用密闭取心现场实验快速判断油层水淹状况[J].海洋石油,2008,(01).
[19]张晓芹,李洁,武力军.密闭取心井资料分析聚驱后剩余油分布规律[A].三次采油技术研讨会论文集[C],2003.
[20]徐守余,宋洪亮.微观剩余油仿真实验研究[J].中国科技论文在线,2008,(11).
[21]贾忠伟,杨清彦,兰玉波,张洪兴.水驱油微观物理模拟实验研究[J].大庆石油地质与开发,2002,(01).
[22]贾忠伟,杨清彦,兰玉波,张洪兴.水驱油微观物理模拟实验研究[J].大庆石油地质与开发,2002,(01).
[23]王刚,王德民,夏惠芬,张立娟.聚合物溶液的黏弹性对残余油膜的作用[J].大庆石油学院学报,2007,(01).
[24]夏惠芬,王德民,刘中春,杨清彦.粘弹性聚合物溶液提高微观驱油效率的机理研究[J].石油学报,2001,(04).
[25]夏惠芬,王德民,王刚,孔凡顺.聚合物溶液在驱油过程中对盲端类残余油的弹性作用[J].石油学报,2006,(02).
[26]岳湘安,张立娟,刘中春,侯吉瑞,夏慧芬.聚合物溶液在油藏孔隙中的流动及微观驱油机理[J].油气地质与采收率,2002,(03).
[27]孟江.水驱油藏剩余油微观分布模拟研究[D].成都理工大学,2007.
[28]Dullien F A L.现代渗流物理学.范玉平,赵东伟等译.北京:石油工业出版社,2001.109~131.
[29]王金勋.应用孔隙水平网络模型研究两相渗流规律[D].中国石油勘探开发研究院,2001.
[30]郭尚平.渗流力学几个方面的进展和建议.见:京:气象出版社,2001:11~22.
[31]张晓军,刘祖原,万明芳.Lattice Boltzmann方法及其应用.武汉理工大学学报,2002;24(2):46~49.
[32]辛峰.用渗流网络模型研究多孔介质中的孔结构和气体扩散[D].天津大学化学工程系,1996,1~21.
[33]Fatt, I. The Network Model of Porous Media, I. Capillary Pressure Characteristics. Trans. AIMM, 1956; 207: 144-159.
[34]Fatt, I. The Network Model of Porous Media, II. Dynamic Properties of a Single Size Tube Network. Trans.AIMM, 1956, 207: 160-163.
[35]Purcell, W.R. Capillary Pressures-Their Measurement Using Mercury and the calculation of Permeability. Trans.AIMS, 1949; 186:39.
[36]Wang S Y, et al. Reconstruction of oil saturation distribution histories during immiscible liquid-liquid displacement by computer-assisted tomography. AIChE Jour. 1984, 30(4): 642-646.
[37]姚军,陶军,李爱芬.利用三维随机网络模型研究油水两相流动[J].石油学报,2007,28(2):94~97.
[38]王克文,关继腾,范业活.孔隙网络模型在渗流力学研究中的应用[J].力学进展,2005,35(3):353~359.
[39]胡雪涛,李允.随机网络模拟研究微观剩余油分布[J].石油学报,2000,21(4):46~51.
[40]李振泉,侯健,曹绪龙,等.储层微观参数对剩余油分布影响的微观模拟研究[J].石油学报,2005,26(6):69~73.
[41]李振泉,侯健,曹绪龙,等.储层微观参数对剩余油分布影响的微观模拟研究[J].石油学报,2005,26(6):69~73.
[42]侯健,李振泉,关继腾,等.基于三维网络模型的水驱油微观渗流机理研究[J].力学学报,2005,37(6):783~787.
[43]Jerauld G R, Salter S J. The effect of pore-structure on hysteresis in relative permeability and capillary pressure: Pore level modeling[J]. Transport in Porous Media, 1990: 103-151.
[44]Mcdougal S R, Sorbie K S.The impact of wettability on waterflooding pore-scale simulation[J]. SPE Reservoir Engineering, 1995: 208-213.
[45]Koplik J, Redner S, Wilk inson D. Transport and dispersion in random networks with percolation disorde[J]. Physical Review A, 1988, 37(7): 2619-2636.
[46]Bryant S, BluntM.J. Prediction of relative permeability in simple porous media[J]. Physical ReviewA, 1992: 2004-2011.
[47]Okabe H, BluntM J. Multiple-point statistics to generate geologically realistic pore-scale representations[C]. Proceedings of the society of core analysts annual meeting, 2003, 22-25.
[48]Blunt M, King P. Relative Permeabilities from two and three-dimensional pore-scale network modeling[J]. Transport in Porous Media, 1991, 407-433.
[49]Greaves,M.and K.Patel. Flow of polymer solution in porous Media.Chemical Engineering Research and Design, 1985; 63: 199-202.