Biochemical binary oil displacement system as well as preparation method and application thereof

The invention provides a biochemical binary oil displacement system as well as a preparation method and application thereof. The biochemical binary oil displacement system is prepared from the following components in percentage by weight: 0.05 to 0.25 percent of a first biological surfactant, 0.05 to 0.25 percent of a second biological surfactant, 0.1 to 0.5 percent of an auxiliary agent, 0.05 to 0.2 percent of a polymer and the balance of water. The preparation method of the biochemical binary oil displacement system comprises the step of uniformly stirring and mixing the first biological surfactant, the second biological surfactant, the auxiliary agent, the polymer and the water. The invention also provides an application of the biochemical binary oil displacement system in improving the crude oil recovery rate in oilfield development. The biochemical binary oil displacement system disclosed by the invention can obviously reduce the oil-water interfacial tension, so that the crude oil recovery rate can be i