MINE APPLICATION METHOD FOR IN-SITU NANO-MICROSPHERES TO INCREASE CRUDE OIL RECOVERY RATE

摘要

A mine application method for in-situ nano-microspheres to increase a crude oil recovery rate. Mine application method comprises the steps: preparing a macromolecule A solution having a mass concentration of 0.1˜5.0% and a macromolecule B solution having a mass concentration of 0.1˜5.0% from site injection water respectively; (2) injecting macromolecule A solution with 0.1˜0.5 times of pore volume into a formation; (3) injecting isolation fluid slug with 0.02˜0.05 times of pore volume; (4) injecting macromolecule B solution with 0.1˜0.5 times of pore volume; and (5) constructing macromolecules A and B rapidly in situ quickly to form nano-microspheres under the drive of hydrogen bonds during the contact process in the formation, thereby promoting fluid flow diversion and increasing crude oil recovery rate. Macromolecules A are of a straight-chain water-soluble polymers with an ethyl ether or propyl ether structure. Macromolecules B are of a water-soluble polymer with a polyhydroxyl or polyphenolic structure.