Oil displacement system suitable for high-temperature and high-salinity oil reservoir

Abstract

The invention discloses an oil displacement system suitable for a high-temperature and high-salinity oil reservoir. The oil displacement system is prepared according to the following method: in an inert atmosphere and in the presence of sodium formate, ethylenediamine tetraacetic acid disodium salt, ferrous sulfate, tetramethylethylenediamine, 4, 4'-azobis (4-cyanovaleric acid), ammonium persulfate and hydrogen peroxide, carrying out a copolymerization reaction among a monomer A, a monomer B, a monomer C, a monomer D and an inorganic component in water to obtain gel; and chopping the gel, adding sodium silicate and sodium pyrophosphate, standing for swelling, drying the swollen gel, and crushing to obtain powder, namely the oil displacement system. Monomer activity (all acryloyloxy monomers) adopted by the invention is high, a high molecular weight product is easy to prepare, and the product is excellent in tackifying performance and small in use amount. The oil displacement system iseasy to store and convenient to transport, and meets the requirements of environmental protection. The method has the advantages of accessible raw materials and favorable preparation technique, and issuitable for industrial production.

Description

technical field [0001] The invention relates to an oil displacement system suitable for high-temperature and high-salt oil reservoirs, belonging to the technical field of oil field chemistry. Background technique [0002] Petroleum is one of the indispensable non-renewable resources in modern society, and its exploitation and utilization play an important role in the development of national economy. With the continuous development of oil extraction, most of the developed oil fields in our country have entered the high water cut period at present. Only through the tertiary oil recovery technology can the output be stabilized and the oil recovery rate increased. Chemical flooding technology is one of the main tertiary oil recovery technical measures to enhance oil recovery in my country, in which water-soluble polymer is one of the key chemical agents for chemical flooding, and the swept volume of the displacement fluid is enlarged through the viscosity increase of the polymer...

AI Technical Summary

Problems solved by technology

[0005] The above-mentioned methods all realize the improvement of polymer temperature and salt resistance by introducing functional monomers. During this process, there are often the following shortcomings: the preparation process of functional monomers is cumbersome, and follow-up operations such as purification are required, which increases product costs; Compared with amide monomers, functional monomers have poor polymerization activity, and the molecular weight of polymers is not high. During use, the concentration of polymers required is high; the introduction of hydrophobic functional monomers and internal salt functional monomers reduces the polymer During use, the dissolution time of the polymer increases and the proportion of insoluble matter increases, which affects the use and promotion of the product

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