爆燃压裂技术在筛管完井污染解堵中的应用

Application of deflagration fracturing technology in plug removal by screen pipe well completion

中国南海东部油田筛管完井的井型比例较高,部分井由于缺乏有效的增产措施而长期处于关井状态。为了解决这一问题,本文以南海东部油田的H-20sb井为例开展爆燃压裂技术的应用研究。在分析爆燃压裂技术对筛管完井井型技术适用性的基础上,通过修正爆燃压裂压力与时间主模型、修正压挡液柱运动子模型、采用筛管泄流子模型替换原射孔孔眼泄流子模型的方法,建立了一套适用于筛管完井的爆燃压裂模型;通过数值计算和爆燃压裂筛管地面打靶试验的方式,优选并确定了安全实施筛管完井爆燃压裂的火药总质量、火药力、燃烧速度、火药单位质量和起爆方式等参数,最后分析爆燃压裂技术在H-20sb井的现场应用效果。研究结果表明,爆燃压裂技术产生的高压气体可以冲刷解堵筛管周围污染物并穿透污染带,扩大后续酸化半径,提高酸化作业效果,最终达到提高油井产量的目的。本文研究成果为筛管完井的增产技术探索了新途径,也为爆燃压裂在筛管完井的进一步应用提供了借鉴。

The proportion of wells running screens in the eastern South China Sea oilfield is high,and some wells are shut in for a long time due to lack of effective stimulation measures.To solve this problem,this paper takes the Well H-20sb in the eastern South China Sea oilfield as an example to work on application test of the deflagration fracturing technology.Based on analysis of the applicability of deflagration fracturing technology to the screen pipe well completion,a set of deflagration fracturing model applicable to the screen pipe well completion are established by modifying the main model of deflagration fracturing pressure and time and the submodel of pressurized liquid column movement,which replaces the original perforation drainage submodel with the screen pipe drainage submodel;Through numerical calculation and ground target shooting test of deflagration fracturing screen,the total amount of gunpowder,explosive force,burning rate,unit dosage of gunpowder and initiation manner for safe running deflagration fracturing screen completion string are optimized and determined.Finally,the field application effect of deflagration fracturing technology in Well H-20sb is evaluated.The experiment results show that the high pressure gas produced by deflagration fracturing technology can scour the pollutants and remove the plugs around screens,penetrate the pollution zone,expand the radius of subsequent acidizing,improve the effect of acidizing operation,and finally achieve the effect of increasing the well production.The research results of this paper not only explore a new way for the stimulation technology of screen pipe well completion,but also provide a reference for further application of the deflagration fracturing in screen pipe well completion.