低渗砂岩油藏水驱开发规律物理模拟研究
Physical Simulation of Water Drive Development in Low Permeability Sandstone Reservoir

低渗砂岩油藏随着我国油气开采技术提高与科技的不断发展，其地位日益显得重要起来，我国的低渗透砂岩油藏储量十分丰富，分布范围也较为广泛，然而，国内对低渗砂岩油藏的开采存在不足，导致低渗砂岩油藏的采收率一般会远远低于其储量。含水饱和度对于油藏的最终产量和采收率的影响很大，因此，本文将在阿尔奇公式的理论基础之上通过实验的方法进行低渗砂岩油藏含水饱和度变化规律物理模拟研究，分析了含水饱和度的变化规律以及影响低渗砂岩含水饱和度变化的压力因素。本文通过调研与实验，得到的主要结论如下：1) 使用阿尔奇公式的方法相较于其他物理模拟方法更加简单，便于操作，适用范围更加广泛，相对更具有可靠性。2) 不同储层具有不同的阿尔奇公式参数，且参数的取值对结果的影响很大，因此对于不同的储层，需要先研究其岩电关系，确定其阿尔奇公式中参数的数值，以保证结果的准确性和有效性。3) 给出了低渗砂岩岩心的水驱过程中含水饱和度变化曲线，分析对比不同压力情况下的曲线，发现压力对含水饱和度的变化有明显的影响，相同情况下，在增大压力后，含水饱和度曲线上升速度增大，且驱替结束时的残余油饱和度减小。
With the improvement of oil and gas exploitation technology, the status of low permeability sandstone reservoir becomes increasingly important. The reserves of low permeability sandstone reservoir in China are very rich and the distribution range is relatively wide. However, the exploitation capacity of low permeability sandstone reservoir is quite insufficient, which leads to the recovery rate of low permeability sandstone reservoir is generally far lower than its reserves. Water saturation has a great influence on the final production and recovery efficiency of reservoirs. Therefore, based on the theory of Archie formula, this paper will conduct physical simulation research on the change law of water saturation in low-permeability sandstone reservoirs through experimental methods, and analyze the change law of water saturation and the pressure factors affecting the change of water saturation in low-permeability sandstone reservoirs. Through investigation and experiment, the main conclusions are as follows: 1) Compared with other physical simulation methods, the method using Archie formula is simpler, easier to operate, more widely applicable and more reliable. 2) Different reservoirs have different parameters of the Archie formula, and the values of the parameters have a great impact on the results. Therefore, for different reservoirs, it is necessary to study their rock-electric relationship and determine the values of the parameters in the Archie formula to ensure the accuracy and effectiveness of the results. 3) The curve of water saturation change in the process of water flooding of low-permeability sandstone cores is given. The curve under different pressure conditions is analyzed and compared, and it is found that pressure has a significant influence on the change of water saturation. Under the same circumstances, after increasing pressure, the rise rate of water saturation curve increases, and the residual oil saturation decreases at the end of displacement.