鄂尔多斯盆地长7储层致密油水平井CO2补充能量与吞吐参数优化

长7储层是鄂尔多斯盆地主要的致密区块，近一半的致密油分布其中。针对长7储层开采渗透率低、开采难度大、依靠弹性开采产能较低、能量衰竭较快等问题，通过数值模拟的方法，构建水平井分段压裂数值模拟模型，首先对比不同吞吐方式对油田产能的影响，优选出CO₂吞吐为首选的补充能量方式。其次对井网形式、井网参数及吞吐参数进行优化研究。最终优选出合适的吞吐方案，达到提高生产效率的目的。结果表明，该储层的最优注采吞吐参数为：周期注入量为2 673 t、注入压力为21 MPa、注入速度为90 t/d、焖井时间为10 d。研究对鄂尔多斯盆地长7储层提高采收率具有一定的参考意义。

Optimization of CO2 Replenishment Energy and Huff and Puff Parameters for Tight Oil Horizontal Wells in Chang 7 Reservoir, Ordos Basin

Chang 7 reservoir is the main tight block in Ordos basin, where nearly half of the tight oil is distributed. Aiming at the problems of low permeability, difficult mining, low production capacity relying on elastic mining and fast energy depletion in Chang 7 reservoir. The numerical simulation model of horizontal well staged fracturing is constructed by numerical simulation. Firstly, the influence of different huff-and-puff methods on oilfield productivity is compared, and CO2 huff-and-puff is selected as the preferred energy supplement method. Secondly, the well pattern, well pattern parameters and throughput parameters are optimized. Finally, the appropriate throughput scheme is selected to improve production efficiency. The results show that the optimal injection-production huff and puff parameters of the reservoir are: cyclic injection volume is 2673t, injection pressure is 21MPa, injection rate is 90t/d, and soaking time is 10d. The study has certain reference significance for improving the recovery rate of Chang 7 reservoir in Ordos Basin.