Enhanced oil recovery mechanism of low oxygen air injection in high water cut reservoir

摘要

Whether air injection can extract additional oil in high water cut reservoirs is a big question. In this paper, long-core displacement experiment has been carried out to investigate the potential of low oxygen air flooding in high water cut reservoirs. Results indicate that implementing low oxygen air injection has potential to improve oil recovery in high water cut light oil reservoir. The reservoir with higher matrix permeability and or lower reservoir permeability contrast ratio is desirable to achieve higher oil recovery factor. In addition, the oil recovery factor for water/gas alternate injection (WAG) strategy is higher than that of continuous low oxygen air flooding. And the WAG strategy has the ability to delay gas breakthrough compared with the strategy of continuous low oxygen air injection under same experiment condition.