The self-adaptive composite waterflooding system has been designed to address the issues of high injection pressure and strong formation heterogeneity uneven water absorp-tion of each layer and prominent interlayer contradiction in offshore J oilfield.The system formula includes 8％gas-generating agent(mass ratio of sodium nitrite to ammonium chlo-ride 1.0:1.1),0.5％foaming agent and 0.3％enhanced system(mass ratio of polymer to phe-nolic crosslinker 1:1).The dynamic and static performance of the system has been investi-gated.Experimental results indicate that the system has the"dual-control"characteristics of controllable foam generation and controllable gel strength.Core experiments demonstrate that the system has a blocking rate of 97.32％,and the increase in recovery rate is 19.59％,45.17％and 57.83％for high,medium and low permeability,respectively.It has excellent performance in adjusting water absorption profiles.Field applications have achieved good wa-ter reduction and oil enhancement effects.This system provides technical support for effi-cient waterflooding development in offshore oilfields and has broad application prospects.
关键词
海上油田/非均质油藏/复合调驱/驱油效率
Key words
offshore oilfields/heterogeneous oil reservoirs/composite profile control and flooding/oil displacement efficiency
维普
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