低渗透油藏分层区块注采井网优化研究

中低渗透油藏在我国分布广泛，具有很好的开发潜力，但由于其渗透率较低，储物性差别较大和油层非均质性严重，所以给开发开采带来很大难度。因此，有必要对此类油藏进行深入的研究。对NH油田为中低渗透油田进行研究，对其资料进行分析可以发现其在开发过程中存在的不足:如在开采初期，区块内一半以上的生产井为天然能量的产油井，天然能消耗较快，地层能量递减很快，采收率偏低，为12.13%；注采井距很大，普遍在350 m以上，井网不适合不完善，注水效果不好，这些都严重制约了该油田的发展。根据实际研究数据，得出该区块的最佳井距为200 m。在对NH油田地质特征和历史生产数据的分析基础上，进一步对其先期的开发效果进行了评价，通过对4种不同的井网形式的注采单元的注水模型进行模拟计算。结果表明，菱形注采井网和九点法注采井网对该油藏的驱替效果相对最好。根据NH油田的地质特征建立相应的H8区块模型，并设计了4套不同布井方式的注采方案，利用油藏数值模拟软件对其进行模拟预测。

Research on injection production well pattern optimization in lowpermeability reservoir stratified block

Medium and low permeability oil reservoirs are widely distributed in my country and have good development potential.However,due to their low permeability,large differences in storage properties and serious oil layer heterogeneity,it is very difficult to develop and exploit.Therefore,it is necessary to conduct in-depth research on such reservoirs.The NH oilfield was a medium and low permeability oilfield,and its data could be analyzed to find its shortcomings in the development process: for example,in the early stage of development,more than half of the production wells in the block were natural energy production wells,and natural energy consumption It was relatively fast,the formation energy declines rapidly,and the recovery rate was low,which was 12.13%;the injection-production well spacing was large,generally more than 350 m,the well pattern was not suitable and imperfect,and the water injection effect was not good development of oil fields.According to the actual research data,it was concluded that the optimal well spacing in this block was 200 m.Based on the analysis of the geological characteristics and historical production data of the NH oilfield,the development effect in the early stage was further evaluated,and the water injection models of the injection-production unit with 4 different well patterns were simulated and calculated.The results showed that the rhombic injection-production well pattern and the nine-point injection-production well pattern had the best displacement effect for the reservoir.According to the geological characteristics of the NH oilfield,the corresponding H8 block model was established,and 4 sets of injection-production plans with different well layout methods were designed,and the reservoir numerical simulation software was used to simulate and predict them.