西南石油大学学报(自然科学版)

• 石油与天然气工程 • 上一篇    下一篇

完井方式对酸蚀蚓孔扩展的影响

柳明1,2,杨鹏1,李德权3,张士诚2,牟建业2   

  1. 1. 中国石油长城钻探工程有限公司,北京朝阳100101
    2.“石油工程”教育部重点实验室· 中国石油大学(北京),北京昌平102249
    3. 中国石油长庆油田分公司第八采油厂,陕西西安710018
  • 出版日期:2014-12-01 发布日期:2014-12-01
  • 基金资助:

    国家科技重大专项(2008ZX05017–003–02–01HZ);国家自然科学基金(51274213)。

Effect of Well Completion on Acid Etched Wormhole Propagation

Liu Ming1,2, Yang Peng1, Li Dequan3, Zhang Shicheng2, Mou Jianye2   

  1. 1. CNPC Great Wall Drilling Company,Chaoyang,Beijing 100101,China
    2. MOE Key Laboratory of Petroleum Engineering,China University of Petroleum(Beijing),Changping,Beijing 102249,China
    3. The No.8 Oil Production Plant of Changqing Oilfield,Xi′ an,Shaanxi 710018,China
  • Online:2014-12-01 Published:2014-12-01

摘要:

在碳酸盐岩油藏酸化中,裸眼完井和射孔完井对酸蚀溶解形态特征的影响不同。酸液在裸眼完井的井筒中与
岩石接触面积远大于射孔完井,酸液受地层非均质性的影响选择性地进入地层,这与射孔完井时酸液针对性地进入地
层不同,有必要对不同完井方式的酸蚀溶解形态进行研究。通过一种达西–孔隙双重尺度模型,创新性地利用正态分
布函数生成模拟区域初始孔隙度值,研究了射孔完井对酸蚀溶解形态的影响,并分析了孔眼沿程滤失的影响。结果表
明:由于射孔在孔眼区产生局部高导流能力的通道,酸液通过孔眼进入地层,溶解形态与裸眼完井不同,且射孔越短蚓
孔分支越多,射孔越长蚓孔分支越少;同一注入速度下,孔眼沿程无滤失的突破体积最小,裸眼完井的突破体积最大;
完井方式和滤失对蚓孔形成的最优注入速度没有影响;当注入速度较小时,由于反应前缘与残酸前缘距离很小,在酸
液临近突破时压力骤然下降,当注入速度较大时,由于反应前缘较宽,压降比较平缓。

关键词: 完井方式, 碳酸盐岩, 蚓孔扩展, 溶解形态, 滤失

Abstract:

In carbonate acidizing,different completion methods have different effects on dissolution patterns caused by acidization.
In this paper,we use a normal distribution function to generate initial porosity values and a two-scale continuum model
to study the effects of perforation completion on dissolution patterns and analyze the effect of leakoff along the aperture. The
results show that the dissolution pattern is very different from that of openhole completion. Acid flows into the formation
through perforation tunnel,and the number of wormhole branches increases with the decrease of perforation length. Under the
same injection velocity,the breakthrough volume of perforation completion without leakoff along the aperture is the least and
that of open-hole completion is the most. Completion and leakoff rarely have effects on the optimum injection velocity. At
small injection velocity,the inlet pressure declines sharply in the termination regime because of a very small distance between
reaction front and spent acid front;at large injection velocity,the inlet pressure declines slowly due to the wide reaction front.

Key words: completion, carbonate, wormhole propagation, dissolution pattern, leakoff