缝洞型碳酸盐岩油藏注气吞吐生产动态及注入介质优选

Dynamic Characteristics of Gas Injection Huff and Puff Production and Influence of Different Gas Injection Medium on the Recovery of Light/Heavy Oil in Fractured-vuggy Reservoirs

赵凤兰 席园园 侯吉瑞 王建斐 马仕希 苏伟 赵腾

ZHAO Fenglan XI Yuanyuan HOU Jirui WANG Jianfei MAShixi SUWei ZHAO Teng

塔河油田缝洞型油藏在底水驱动或注水替油开采结束后，仍存在阁楼油、绕流油和井间油等多种剩余油类型。为了获得不同缝洞连通情况下注气吞吐生产动态，揭示不同注气吞吐介质对轻质/重质原油采出程度的影响规律，利用依据地质资料设计的室内三维物理模型，模拟底水条件下典型缝洞结构单元的注水替油过程及注气吞吐过程，考察了相同条件下不同原油黏度（1094.5 mPa·s 和23.6 mPa·s）与不同气体介质（N2、CO2、复合气（N2∶CO2=1∶1））对剩余油的启动效果。结果表明，注气吞吐控水增油效果明显，N2、CO2通过重力分异作用可置换阁楼油，通过气体膨胀作用携带井间油及绕流油；对于黏度为1094.5 mPa·s 的稠油，注N2、CO2、复合气（N2∶CO2=1∶1）对模型采出程度的提高幅度分别为19.59%、14.54%、7.55%，而对黏度为23.6 mPa·s 的稀油，注气吞吐采出程度分别提高10.87%、10.12%、7.41%，注气对稠油的吞吐效果优于稀油，且N2和CO2吞吐效果优于复合气（N2∶CO2=1∶1）。图10 参16

Tahe fractured-vuggy reservoirs have a variety of residual oil，such as attic oil，inter-well oil，et al，after bottom water driving oil or water-flooding and replacing oil. In order to analyze the dynamic characteristics of gas injection huff and puff production and the influence of different gas injection medium on the recovery of light/heavy oil reservoir，the injecting water replace oil and injecting gas huff-and-puff was simulated with an indoor 3D physical model，which was designed based on the geological datum，the huff-and-puff effect of the three gas mediums（N2，CO2 and composite gas（N2∶CO2=1∶1））on residual oil was studied at the different viscosity of 1094.5 mPa·s and 23.6 mPa·s. The experimental results showed that the injecting gas huff-and-puff could control the bottom water and increase oil production obviously，N2，and CO2 could replace attic oil by the impact of gravitational differentiation，and flow around oil and inter-well oil could be carried by the impact of gas swelling. After N2，CO2 and composite gas huff-and-puff，the oil recovery for the heavy oil with the viscosity of 1094.5 mPa·s was enhanced by 19.59%，14.54% and 7.55%，respectively；while the oil recovery for the light oil with the viscosity of 23.6 mPa·s was enhanced by 10.87%，10.12% and 7.41%，respectively. The effect of injecting gas huff-and-puff for heavy oil was better than that for light oil under this experimental condition，and the effect of N2、CO2 huff-and-puff was better than that of composite gas（N2∶CO2=1∶1）.

10.19346./j.cnki.1000-4092.2017.03.017