Analysis of the effect of viscoelastic self regulating agent in the Jurassic reservoir of Wu A district
The bottom water reservoir of Yan 9 and Yan 10 in Wu A area has experienced a significant decrease in water drive utilization since 2017,with only 38.0%.Due to the influence of gravity,the water absorption section gradually moves downwards.Due to the strong heterogeneity of the formation and interlayer,as well as the strong injection and production intensity in the early stage,the bottom water cone prematurely leads to water breakthrough in the oil well,and even causes water whelming.Conventional water plugging and profile control measures cannot complete the sealing of deep areas of the formation.In order to delay the injection of water along deep high permeability channels such as large pores and micro cracks,increase the swept volume of injected water,and improve the water absorption profile,the Yan 9 and Yan 10 oil reservoirs in Wu A area conducted a field test of viscoelastic self regulating agent in August 2022.The test results showed that after vis-coelastic self regulating agent was injected from August 2022 to October 2023,the effect of profile control and displacement was good,and it could effectively stay in the pore throat.The average daily water injection volume of a single well decreased,and the injection pres-sure increased from 7.20 MPa to 7.80 MPa.The overall water absorption index decreased from 38.1 m3/(d·MPa)to 25.1 m3/(d·MPa).Viscoelastic self regulating agents formed effec-tive sealing in the formation,effectively improving the oil-water flow ratio and enhancing oil washing efficiency.After injecting viscoelastic self regulating agent,the monthly decline rate decreased from 0.10%to-0.40%,and the monthly increase in water content decreased from 0.03%to 0.02%.
bottom water reservoirpolymerviscoelasticitydeep profile control
NETL
NSTL
万方数据
维普
