摘要
造成低渗透储层注水井吸水能力下降的原因主要包括:孔喉半径小、连通性差,原油物性差,油水井距过大,储层存在强-中水敏和中-弱酸敏,尤以注入水对储层伤害最大。室内实验研究了不同渗透率岩心在不同水质下的岩心伤害数据,结果显示,污水中悬浮物粒径超标对岩心的伤害最大,其次是悬浮物含量和油含量,细菌含量对岩心伤害程度较弱;渗透率级别越低,污水超标引起的伤害越严重,渗透率级别小于10×10-3μm2的岩心对污水超标十分敏感。结合油田矿场实际,提出了储层伤害周期的评价方法,确定了注水井吸水能力下降幅度与水质、累积注水量之间的关系。实验还认识到实际储层伤害的半径比现场认识的半径更大,为此提出应用复合解堵技术、缓速技术、强穿透技术、强力螯合技术、储层孔道保护技术等,进行周期性注水解堵增注的建议。
The reasons of water injection capacity decreasing of injection well in the low permeable reservoir are：small pore throat,poor connectivity,and bad physical property of crude oil,oversized injector-productor well spacing and strong-medium water sensibility and medium-weak sour sensitivity in reservoirs.In particullaly ,the injected water has the largest damage on reservoirs.According to the research data of the core dam- age of different water quality in different-permeability core in house laboratory.The results indicates that the greatest damage of core comes from superstandarded grain size of suspended material in the waste water;the greater comses form content and oil content of the suspended material ;and the weakest comes from the bac- teria content.The lower permeability brings greater damage caused by the superstandarded waste water.The cores with the permeability lower than 10×10^-3μm2 are much sensitive to the superstandarded waste water.An evaluation means of the reservoir damage period is put forward according to the actual field conditions.The relationship between descending scope of absorbing capacity of the injection well and water quality and cu- mulative water injection quality is confirmed.Meanwhile the research shows that the radius of actual reservoir damage is harder than the knowing in place,so cyclic water injection should be applied to broken down stimulation by the related technologies.
出处
《中外能源》
CAS
2010年第6期56-59,共4页
Sino-Global Energy
关键词
低渗透
水驱
储层伤害
解堵
low permeability
water drive
reservoir damage
broken down
