Research on the effect of waterflooding with surface active agent in low permeability reservoir

Some related research findings show that an appropriate surface active agent can reduce the injection pressure of low permeability reservoir. The average reduced rate of 8 samples is 26. 6% and the enhanced displacement efficiency is 6.7%. After the solution action of surface active agent, the phase permeability curve changes obviously:the relative permeability of oil and water raises, two- phase flow domain becomes wider, and rock wetta-bility drifts towards the hydrophilic direction. The result shows that the compound 2# surface active agent is able to improve the waterflooding of Baolang oilfield which has low peamibility.