水平井注水生产动态特征研究

为了研究水平井注水的生产动态特征,以渤海BZ油田为例,对比分析了水平井与直井注水在霍尔曲线、注入压力、日注水量、视吸水指数四个参数的不同特征。研究发现,水平井注水初期井筒类似于一个"压力腔",它的存在导致水平井与直井注水生产动态的差异。如霍尔曲线形态典型不同;水平井注水压力低于直井,且低压持续时间是直井的1.8倍,压力爬升时间是直井的12倍;在相同注水压力条件下,每米地层厚度水平井注水强度是直井的3倍;水平井注水吸水差异大于直井,视吸水指数级差倍数是直井的9倍。针对上述特点,分析认为水平井井型和井筒内复杂的渗流流动是水平井与直井注水差异的根本原因。

Study on Dynamic Performance of Horizontal Wells in Water Flooding

In order to research the production dynamic performance of horizontal wells in water flooding, taking Bohai BZ oilfield as an example, different characteristics of the Hall curve, injection pressure, daily water injection rate and apparent water injectivity index of the horizontal wells and vertical wells were comparatively analyzed. The results show that horizontal wellbore is similar to a "pressure cavity" in early water injection, which leads to different injection production performance of horizontal wells and vertical wells. The injection pressure of horizontal wells is lower than that of vertical wells, and the duration of low pressure is 1.8 times that of vertical wells; the pressure climbing time is 12 times that of vertical wells; under the condition of same water injection pressure, the injection intensity of one meter formation thickness of horizontal wells is 3 times that of vertical wells; In the same work statu, the apparent injectivity index of horizontal wells is 9 times that of vertical wells. According to the above characteristics, it's pointed out that the special well type of horizontal wells and the complex seepage flow in the wellbore are the root cause of the difference of horizontal wells and vertical wells in water injection.