陆梁油田薄层底水油藏水平井井筒模拟研究

Study on the Horizontal Wellbore Model of Thin-layered Bottom-water Reservoir in Luliang Oilfield

新疆陆梁油田呼图壁河组油藏发育一类特殊的薄层底水型油藏,其特点是油层厚度薄,构造幅度低,底水能量大,利用水平井开采,表现出无水采油期短、含水率上升速度快、产量递减大的特点。针对这些问题,采用水平井数值模拟方法,建立了考虑摩擦压力损失的水平井井筒模型,明确了摩擦压力损失对水平井的压力分布以及水平段产量的影响,在此基础上,分析研究了水平井底水锥进的水脊特征,判断了水平井出水位置,提出了封堵出水井段并结合油藏工程方法确定了水平井合理产液量,从而达到抑制底水快速锥进,减小压力损失,降低含水率上升速度的目的。

A special thin layer of bottom water reservoir has developed in Hutubi River Layer in Luliang Oilfield of Xinjiang. This kind of reservoir has thin thickness, small sand body amplitude and large bottom-water energy. Drilled with horizontal well, this kind of reservoir has possessed some characteristics such as short water free production period and water-cut with faster ascending velocity and big decline production. Aiming at solving these problems, we established the horizontal well- bore model which takes the pressure loss into consideration with the numerical simulation method, and obtained the pressure distribution of horizontal wells and the influence of horizontal section production due to the pressure loss. On this basis, we analyzed the features of water cresting characteristic of the horizontal well bottom water coning, and judged the location of water breakthrough in horizontal section. Finally, the paper suggests that the reasonable liquid production can be achieved by plugging the location of water breakthrough and using pump which has smaller diameter. Such method will control bottom water coning and decrease the pressure loss and reduce the water cut increasing rate.