摘要
安塞油田属开发30年"低压、低渗、低产"老油藏,目前年产300×10~4t。但近年来随着老区不断加密,地下井网及水驱控制储量不断发生变化,剩余油受裂缝影响主要在侧向富集,剖面上单砂体动用严重不均,Ⅱ+Ⅲ类储层动用比例低。为提高加密区新建单井产能,文章从射孔段优化、提高裂缝穿透比、增加铺砂浓度、多缝压裂增加泄油面积等方面进行探索,试验了定面射孔+变排量压裂、多级加砂压裂、水力喷射定点压裂等针对不同储层特征的特色工艺对剩余油进行挖潜。结合新型稠化水压裂液体系,结果表明,定面射孔+变排量工艺针对上下隔层地应力差值小的薄油层或底水油层,斜井多段压裂在井斜角大、井斜方位有利时针对厚度较大且不具备泥岩隔层遮挡条件油层,多级加砂压裂对油层厚度大的能充分改造,定点射孔压裂对水洗特征明显且不规则的油井具有较好的工艺适应性和改造优势,因地制宜地选择特色工艺,改造后平均单井初期产能相比同类井常规改造提高0.45 t。
Ansai oilfield has been developed thirty years,it's an old low pressure,low permeability and low production oil reservoir,producing 3,000,000 tons per year. With more infill wells in the main reservoir and the changes in reserves controlled by underground well network and water flooding,the residual oil accumulates laterally,the single sand bodies are recovered extremely uneven,low percentage of II + III type reservoirs be produced. Optimization of perforation section, increasing crack penetration ratio,increasing sand concentration,increasing oil discharge area with multiple fracture fracturing,testing the fixed surface perforation + variable displacement fracturing,multistage sand fracturing and fixed-point hydraulic jet fracturing are tried to tap different remaining oil. The average productivity of single well is increased by 0. 45 t when comparing with the conventional stimulation. The processes have showed a good adaptability to the reservoirs.
出处
《钻采工艺》
CAS
北大核心
2018年第4期41-44,共4页
Drilling & Production Technology
关键词
安塞油田
加密井
单井产能
定面射孔
多级加砂
Ansai oilfield
infill well
single well rate
fixed surface perforation
multi-stage sand loading
