Abstract:

Using synthetic fluids of separate oil and gas samples from Wangxin-10-2 well compounded according to gas oil ratio 21. 36m3/t, flooding experiments have been conducted upon long real formation core from Wangsixie-10-3 well to research flooding efficiencies by dry gas injection. The experiments have been
done under two cases: the core is horizontal and the core has 50 degree’s angle of inclination. Results show that the recovery with the core having 50 degree’s angle of inclination is higher than that with the core horizontal when the same volume of dry gas are injected after water flooding in north fault-block of Wangchang oil field. The recovery enhanced by dry gas injection after water flooding is 5.01% when the core is horizontal;while it is 8.41% when the core has 50 degree’s angle of inclination. It is also demonstrated that the displacement efficiency by dry gas injection with the core inclination is more obvious, and the enhanced recovery is higher.

Key words: north fault-block, lab research, water flooding, immiscible