我国注水油田常规注水潜力宏观评估

Macroscopic Evaluation of Potential by Routine Water Injection Methods in Chniese Water Injection Oilfields

俞启泰 罗　洪

中国石油天然气集团公司勘探开发科学研究院

Research Institute of Petroleum Exploration and Development , CNPC , Beijing 100083 ,P. R. China

评估了我国注水油田用常规注水方法能够提高采收率的最大幅度。以1997 年的采收率为基准,采用如下常规注水方法提高采收率幅度: ①延长油田生产含水率界限,含水率从0. 98延长到0. 99 ,可提高采收率1. 7 %; ②钻加密调整井可提高采收率1. 8 %; ③降低油水井数比可提高采收率0. 6 %; ④注采井距均匀化可提高采收率0. 4 %; ⑤各种井下措施可提高采收率0. 5 %。合计可最大提高采收率5 %。据统计,我国注水砂岩油田1997 年采收率为0. 355 ,这样,用常规注水方法,采收率最大可提高至0. 405 。

The maximum range of oil recovery efficiency could be raised by routine water injection methods in Chinese water injection oilfields. Based on the ultimate oil recovery efficiency in 1997, the following routine water injection methods and the maximum range of oil recovery efficiency, which can be raised by them ,are as follows : (1) extending limit of water cut to produce ,from 0. 98 to 0. 99 ,can raise oil recovery efficiency by 1. 7 percent; (2) infill well can raise oil recovery efficiency by 1. 8 percent ; (3) lowering the ratio of producers and injectors can raise oil recovery efficiency by 0. 6 percent ; (4) evening distances between producers and injectors can raise oil recovery efficiency by 0. 4 percent ; (5) carrying on every well measures can raise oil recovery efficiency by 0. 5 percent. The maximum range of raising oil recovery efficiency by the 5 routine water injection methods is 5 percent. By statistics, the oil recovery efficiency in 1997 in Chinese water injection oilfields is 0.355 on the average. Thus, by routine water injection methods, the average oil recovery efficiency can be raised to 0. 405.