江苏油田小断块低渗油藏压驱注水技术实践

Practice of pressure drive water injection technology in small fault block reservoir of low permeability in Jiangsu oilfield

江苏油田目前进入开发中后期,小断块低渗油藏面临压力水平低、采收率低、采出程度低的难题,目前开发方式以注水开发为主,采取注水开发的油田有35个,水驱储量达到1.86×108t,占油田总储量的74.7%。为解决注水开发过程中日注量低、欠注比例高、水驱采出程度低的问题,提出采用压驱注水技术。并从压驱机理、压驱选井、压驱注入量、注入排量、焖井时间、压驱液优化等方面开展了探讨,有效指导了现场实践,目前已完成3井次压驱施工,日增油3.6 t,累增油388.9 t,增油效果还有待继续跟踪观察,下步需要继续开展压驱机理及不同油藏压驱注入参数研究。

At present,Jiangsu oilfield is in the middle and late stage of development,the small fault block reservoir of low permeability is facing the problem of low formation pressure,low recovery ratio and low reserve recovery.Water flooding is the main oilfield method,there are 35 oilfields using water injection,waterflooding reserves have reached 186 million tons,which accounts 74.7%of total reserves.Pressure drive water injection technology is proposed to solve the problems of low daily water injection volume,high proportion of under injected wells and low water flooding reservoir recovery degree,and discussed from mechanism,selection of well and layer,injection volume,water injection displacement,the well closed time,optimization of liquid system and so on.It effectively guides the field practice,up to now,pressure drive water injection technology has been used in three wells,leading to an increase of 3.6 t/d,accumulate adding oil for 388.9 t,oil increasing effect remains to be observed.The next step is to continue to study the pressure drive mechanism and injection parameters of pressure drive in different reservoirs.