川口油田长6油层注水解堵开采研究

Study on Production by Water Injecting for Broken Down in Oil Layer Chang 6 of Chuankou Oilfield

川口油田属特低渗透油田,平均空气渗透率为0.79×10-3～0.96×10-3μm2,储层物性差,油藏压力低,渗透率特低,基本无自然产能,水力压裂求产后产能下降快。1998年油田开始注水,随着注水时间的延长,油田开发矛盾也在逐渐暴露,主要表现为水淹井多、吸水剖面不均匀、部分油井见效缓慢。为最大限度地发挥油层潜力,根据油藏地质特征和油水运动规律,进一步完善注采井网,完善注采对应关系,以反九点法井网为主的川口油田注水开采,取得了突破性的发展;严格控制注水参数,解决了水质超标、注水井注不进水、注水井堵塞、油井水淹等技术难题。油井增产明显,取得了一定的经济效益和社会效益,逐步确定了一套适合川口油田注水开发的工艺流程和工艺技术。为特低渗透油田提高资源利用率,提高原油采收率闯出了一条新的路子。

Chuankou oilfield belongs to the low permeability oilfield with an average air permeability of 0.79×10^-3-0.96×10^-3μm2.The physical characteristics of reservoir is poor,reservoir pressure is low and permeability is very low without self-production capacity.The production reduces quickly after acquiring production by hydraulic fracturing.Oilfield began water injection in 1998.As the waterilooding time prolongs,the contradiction of oilfield development is exposing,which displays in more water-cut wells,uneven injection profile and some wells with low efficiency.To trap the reservoir potential,the injection and production pattern arid relationship are further improved based on the geology characteristics and oil-water movement law.A great advance is gotten for the waterflooding production of Chuankou oil wells by inverted nine-spot injection pattern. Controlling the water injection param＇eter solves the problems as water quality,difficult injection,well plugging and watered cut,which has acquired certain economical benefit.On this base,we determine a set of technologies suitable for waterflooding development in Chuankou oilfield.This provides a new path for making use of resource and enhancing oil recovery in very low permeability reservoir.