Preparation method of high-temperature-resistant high-salt polymer oil-replacement agent

Abstract

The invention relates to a preparation method of a high-temperature-resistant high-salt polymer oil-replacement agent, which comprises the following steps: dissolving 10-20 parts by weight of anionic monomer, 50-65 parts by weight of sodium allylsulfonate, 11-22 parts by weight of cationic monomer, 2-4 parts by weight of acrylate, 0-3.5 parts by weight of alpha-alkene and 50-60 parts by weight ofacrylamide in deionized water, wherein the total mass concentration of the monomers is 15-23%; adding a surfactant which accounts for 1-5% of the total weight of the monomers, regulating the pH valueof the solution to 9-10, introducing ammonia gas at 30-60 DEG C for 30 minutes, and adding a persulfate initiator which accounts for 0.05-0.1% of the total weight of the monomers; and reacting at 30-60 DEG C for 12 hours, precipitating with acetone, washing, and carrying out vacuum drying to obtain the white powdery polymer. The invention is characterized in that long-carbon-chain alkyl group, anionic and cationic unit structures are introduced into the water-soluble polymer macromolecules to obtain the high-temperature-resistant high-salt water-soluble polymer oil-replacement agent.

Description

technical field [0001] The invention relates to a preparation method of an auxiliary agent in the field of oil recovery, in particular to a preparation method of a high-temperature and high-salt polymer oil displacement agent. Background technique: [0002] At present, polymer flooding technology is the main technology to enhance oil recovery in oilfield development. It is successful in technology and economy. It has been widely used at home and abroad, and has broad application prospects. [0003] In the current stage of oil and gas production, the stability requirements of water-soluble polymers are getting higher and higher, and the stability includes shear stability, chemical stability, thermal stability, biological stability and long-term stability. Specifically, water-soluble polymers can maintain a certain viscosity under the influence of high salinity, high temperature, high shear and different pH values. This is also an aspect that is currently being considered in...

AI Technical Summary

Problems solved by technology

The cations in the aqueous solution, especially the divalent ions, will shield the ionic groups in the polymer, make the polymer molecular chain curl, reduce the hydrodynamic volume or even precipitate, so that the viscosity increase is greatly reduced

Images