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黏滞力和毛管力的比(一般表示为毛管数N_c)在确定残余油饱和度方面是至关重要的。在从接近中间润湿转变到强水湿的润湿性条件下,确定了通过系统增大N_c对均质白垩岩残余油饱和度的影响。在裂缝性白垩岩油藏中水驱残余油饱和度在很大程度上取决于润湿性。通过测量N_c不同时的可动油量,有助于确定三次采油的潜在目标。进行了一系列的注水驱油试验,以确定在不同润湿性条件下水驱中残余油量和增大毛管数之间的关系。通过Amott试验,用21个岩心柱样品建立并且量化了各种均匀分布混合润湿性条件。在水的Amott指数为0.3的润湿性条件下,N_c稳定时残余油最少。残余油饱和度随着毛管数增大而降低,在中等水湿到接近中间润湿条件下,水自吸后捕集的大量油开始流动。当增大毛管数时,在白垩岩油藏中得到的结果与在文献中报道的砂岩水驱残余油饱和度(随着润湿性和注入水PV变化)的结果相似。在采收率随着毛管教增加同时提高的情况下,采收率的穹隆形曲线(随着润湿性变化)反映了与较早水驱采收结果的相似性。
The ratio of viscous force to capillary force (generally expressed as the number of capillary N_c) is crucial in determining the residual oil saturation. The effect of increasing N_c on the residual oil saturation of a homogeneous chalkingstone through the system was determined under wetting conditions from near-intermediate wetting to strong wetting. The water-flooding residual oil saturation in fractured chalky reservoirs is strongly dependent on wettability. By measuring the amount of movable oil that is not the same at Nc, it is helpful to determine the potential target of tertiary recovery. A series of flooding experiments were conducted to determine the relationship between the residual oil volume and the number of capillary tubes in a water flooding under different wettability conditions. Through the Amott test, 21 core column samples were used to establish and quantify various well-distributed mixed wettability conditions. Under the wettability condition of water with Amott index of 0.3, residual oil is the least when N_c is stable. Residual oil saturation decreases as the number of capillary tubes increases, and from medium to near-intermediate wet conditions, large quantities of oil trapped after water self-priming begin to flow. The results obtained in the chalk reservoir are similar to those reported in the literature (as wettability and PV changes in injected water) when increasing the number of capillaries. The dome shape of the recovery (with changes in wettability) reflects similarities with earlier waterflood recovery results as oil recovery increases with increasing capillary pressure.