Research and application of adaptive composite regnlation and flooding technology in offshore J oilfield
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.
offshore oilfieldsheterogeneous oil reservoirscomposite profile control and floodingoil displacement efficiency