关键词: 水驱油藏, 高渗透区, 深部液流, 柔性转向剂, 韧性, 黏弹性, 动态堵塞

Abstract: In order to restrict injection water flowing through high-permeability zones and improve fluid flow field in water flooding reservoirs,a kind of flexibile agent SR-3 was developed for getting diversion of deep flooding fluid.The SR-3 with high chemical stability and good toughness could be deformed randomly.The physical simulation in laboratory showed that the SR-3 could migrate through channels in high-permeability zones,which resulted in profile control along the track of the SR-3 particles.The SR-3 flowing in the channels of high-permeability zone can be deformed and produce a plugging pressure when it meets pore throat.The SR-3 will creep through the channels as the flow pressure increases to a breakthrough point,then it flows towards a balance with pressure drop.Afterwards,the SR-3 particles will repeat similar processes along the channels in high-permeability zones,which results in a dynamic plugging in deep reservoir.A pilot test of the flexible agent injected into an oil layer in the east part of Daqing Oilfield validated above mechanism and also demonstrated that the channels and high-permeability zones were produced along the primary route with long period water flooding in fissureless sandstone reservoirs.The sweep efficiency of water flooding can be improved greatly if the dynamic plugging happens along the channels.

Key words: water-flooding reservoir, high-permeability zone, deep flooding fluid, flexible agent, toughness, viscoelasticity, dynamic plugging