A Study on the Technology of Steam - Hot Water - Nitrogen Compound Drive after Steam Channeling in Steam Flooding

Nowadays most heavy oil reservoirs are developed by thermal recovery methods, such as steam huff - puff and steam flooding. At the late stage of heavy oil steam drive, because of steam overlap in the upper reservoir formation, steam channeling can easily occur in production well. The research has shown that development effect of steam - nitrogen compound drive is not as good as consideration after steam channeling. But by injecting water slug can decrease the effect of steam channeling. For increasing water phase saturation in high permeability channel, steam and nitrogen gas relative permeability will decrease. As result, it will enlarge the reservoir vertical producing degree, and at the same time take full advantage of the oil displacement effect of steam - nitrogen compound drive. Through the numerical simulation, the study found that, steam - water - nitrogen compound drive technology can achieve better recovery degree using high hot water temperature and shorter injection time.