超低界面张力泡沫体系驱先导性矿场试验研究

超低界面张力泡沫体系驱是一种全新的三次采油方法,驱油效果优于三元复合驱,可比水驱提高采收率25％左右。通过室内综合研究,确定了超低界面张力泡沫体系驱试验方案,并在大庆油田进行了先导性矿场试验。试验结果,油层中有大量泡沫生成,扩大了波及体积,提高了洗油效率,注入井注入压力上升,注采压差大幅度增加,吸液指数和产液指数大幅度下降,增油降水效果显著,气窜现象得到抑制。超低界面张力泡沫体系驱应该采用双管分注工艺,否则易产生水化物;由于注气压力较高,应采用更高性能的压缩机设备,以保证达到设计的气液比要求。图3表3参10

Pilots of ultra-low interfacial tension foam flooding

The ultra-low interfacial tension foam flooding (LIFTF) is a new tertiary recovery method. The displacement efficiency is better than ASP flooding, and the recovery is improved by around 25% than water flooding. By laboratory studies the testing program was determined and the pilots of LIFTF were carried out in Daqing Oilfield. Large amounts of foam generated in the reservoir, the sweep volume increased and the oil displacement efficiency improved. The injection pressure rised and the pressure difference between injector and producer enlarged obviously. The fluid injectivity and productivity index increased greatly, oil production increased and water production decreased greatly, and gas breakthrough is controlled effectively. The dual string injection should be used in the LIFTF to avoid the generation of hydrate. Because of the higher injection pressure, the compressor of better performance should be adopted to meet the request of the designed gas/liquid ratio.