华庆油田Y2区空气泡沫驱注入参数优化

Injection parameter optimization of air foam flooding in Y2 of Huaqing oilfield

华庆油田Y-2区长6储层属于典型的超低渗油藏，平均渗透率0．3mD，由于储层非均质性严重，且局部微裂缝比较发育，开发过程中具有单井产量低、含水上升快、水驱动用程度低的特点。为进一步提高纵向动用程度、提高驱油效率，提出进行空气泡沫驱油。在对试验井组建立三维精细地质模型的基础上，利用数值模拟方法对空气泡沫驱的注入参数进行了优化。优化后的泡沫注入速率为20～30m^3／d，注入量为0．02～0．04PV，气液比为1，单个泡沫段塞为0．0033PV，对应的单个段塞注入时间为3个月。利用优化后的注入参数进行空气泡沫驱油，预测10年末采出程度可提高4．24％，累积产油增加8．32万t，含水率可保持在50％以下。

Chang 6 reservoir in Y2 area of Huaqing oilfield is a typital ultra-low permeability reservoir with mean permeability of 0. 3 mD. Because of the serious reservoir heterogeneity and micro-fracture, there are producing characteristics of the low producing rate and high water cut. In order to improve the vertical producing reserves and displacement efficiency, the air foam flooding technology is adopted. On the base of establishing triaxial geologic model, the injection parameters of air foam flooding is optimized. The results show the optimal foam injection rate is 20-30 m^3/d, the optimal injection volume is 0. 02-0. 04 PV, the optimal gas liquid ratio is 1 ： 1, the optimal single foam slug is 0. 003 3 PV, and the corresponding injecting time of single foam slug is 3 months. With the optimum injecting parameter, the degree of reserve recovery with air foam flooding is advanced by 4. 24%, the cumulative oil production is advanced by 8. 32×10^4 t, and the moisture content can keep below 50% according to the forecast of the end of 10 years.