深层稠油油藏Ⅰ-2型普通稠油水驱油可行性评价

Evaluation on the Feasibility of Water Flooding for Deep Ⅰ-2 Normal Heavy Oil Reservoir

泌276断块深层I-2型普通稠油油藏采用天然能量开发效果较差,急需转换开发方式。由于深层稠油采用热采开发工艺技术难度大且经济效益较差,因此可行性不高。一些深层稠油油藏采取常规注水开发方式的效果较好,但原油黏度基本都小于300mPa·s。原油黏度介于300~500MPa·s之间的Ⅰ-2类普通稠油的注水开发可供借鉴的经验不多。为论证注水开发可行性,开展了水驱油效率室内评价实验,并通过类比法确定了注水开发的驱油效率下限。结果表明,工区注水开发的驱油效率下限为28%,由于水驱油实验0.5PV之后的驱油效率均大于30%,且储层物性、流体属性等与邻区转水驱效果较好的王9断块类似,因此可以认为,注水开发可取得较好的开发效果,天然能量转注水开发是可行的。

The natural energy development effect of the deep Ⅰ-2 normal heavy oil reservoir is poor, and it is urgent to change the development mode. Because the deep heavy oil production is difficult by using thermal recovery technology and the economic benefit is poor, the feasibility is not high. Some deep heavy oil reservoirs have good development effect by using conventional water flooding, but crude oil viscosity is less than 300 mPa·s. Waterflooding for Ⅰ-2 ordinary heavy oil with the viscosity of 300~500 m Pa·s don’t have much reference experience. In order to prove the feasibility of water flooding, an evaluation experiment of water drive efficiency was carried out in the laboratory, and the lower limit of oil displacement efficiency was determined by analogy method. The results showed that lower limit of oil displacement efficiency by water flooding was 28%, because the displacement efficiency of experiment were greater than 30% after 0.5 PV, and the reservoir physical properties, fluid properties and so on were similar to the adjacent regions Wang 9 block, water flooding effect of which was good. So the water injection development can achieve better effect, and is feasible.