Patent ID: 8859258

Claim:
A composite oil displacement agent, comprising the following components in parts by weight: from 20 to 40% of Protaminobacter alboflavus microorganism CGMCC 4670 bacterial liquid; from 6 to 30% of a surfactant; from 5 to 10% of a macromolecular modifier; from 1 to 5% of a viscosity reducer; from 1 to 5% of an additive; and the balance of water; wherein a concentration of the microorganism in CGMCC 4670 bacterial liquid is between 108 and 1010 bacteria per gram, and the macromolecular modifier is one or more than two of the group consisting of sodium methylcellulose, methylcellulose M20, hydroxyethylcellulose, hydroxypropylcellulose, polyethylene glycol 600, polyethylene glycol 6000, polyvinylpyrrolidone and polyvinyl alcohol.