摘要
由于油层非均质性和长期水驱,油水井之间形成了大孔道。大量注入水沿着大孔道无效循环,降低了水驱波及系数。矿场试验证明基于弹性变形通过孔喉的柔性转向剂SR-3,对大孔道实现了有效封堵,但其在地层运移规律及深部液流转向机理还需进一步深化。采用孔喉模型对SR-3在大孔道中的运移规律及其封堵大孔道产生的液流转向能力进行了实验研究。分析了喉粒径比、平均喉道长度、驱替液的注入速度对门槛压力的影响及SR-3颗粒的剪切破坏。结果表明SR-3可以变形通过窄小孔喉,在大孔道中产生沿程脉动阻力,实现深部液流转向,提高水驱波及系数。对一定孔隙,有最优喉粒径比,使SR-3在地层中平稳运移,实现深部液流转向。SR-3运移到地层深部是其提高波及系数和采收率的主要因素;SR-3的弹性变形有利于其运移到地层深部。
Currently most of the oil oilfields in east China have been entering the late period of high water-cut development stage.Due to non-homogeneous formations and long-term water flooding,large pores come into being among oil-water wells.Great amount of water rotates deficiently along the pores and decreases the waterflood sweep efficiency.Field test shows that flexible particles(SR-3)can seal off the large pores effectively,but the migration mechanism needs further study.The paper mainly studies the migration of flexible particles in pores,and the capability of turning fluid direction generated by sealing pores with pore throat models.What's more,it analyzes the effect of throat-particle diameter ratio,average length of throat,and injection rate of displacement on threshold-pressure and the shear damage of flexible particles.Results show that the flexible particles can go through little porous throat by deformation and generate continued fluctuate resistance in large pores,which helps to realize deep fluid diversion and enhance waterflood sweep efficiency.There exists the optimal ratio with throat-particle diameter to certain pores,which enables SR-3 to migrate stably in the formation.The migration of flexible particles to deep formations can greatly improve sweep efficiency and enhance oil recovery.And the elastic deformation of SR-3 is favorable for its migration to deep formations.
出处
《石油钻采工艺》
CAS
CSCD
北大核心
2007年第4期80-82,99,共4页
Oil Drilling & Production Technology
基金
中国石油股份有限公司"十五"重大科技项目"深部液流转向改善水驱技术研究"
项目编号:050116-9
关键词
柔性转向剂
大孔道
深部液流转向
喉粒径比
模拟实验
flexible particle
enhanced large pores
turning fluid direction in deep reservoir
throat-particle diameter ratio
simulating experiment
