注水开发稠油油藏转蒸汽驱提高采收率

Enhance Oli Recovery by Changing Waterflooding for Steamflooding in Heavy Oil Reservoirs

分析了水驱稠油油藏剩余油分布特征、水驱开发过程中原油性质的变化情况以及引起原油性质变化的主要原因。论述了蒸汽驱提高采收率的开采机理、水驱转蒸汽驱时机及注汽参数对开采效果的影响，阐明了稠油油藏水驱后期转蒸汽驱开采的技术策略。

This paper studies residual oil distribution and crude oil property variations in waterflooding heavy oil reservoirs, and analyzes the main causes of crude property variation. The mechanism of enlarging swept volume through steam-flooding is further discussed and the principles for selecting the opportune time to change waterflooding for steam flooding is also presented. The operability of this technique is improved through analyzing the effects of steam flooding on development effectiveness and the points for attention when performing steam flooding at the late development stage of waterflooding heavy oil reservoirs.