A flooding system suitable for high temperature and high salinity reservoirs

Abstract

The invention discloses an oil displacement system suitable for high-temperature and high-salt oil reservoirs. The oil displacement system is prepared according to the following method: in an inert atmosphere, in sodium formate, disodium edetate, ferrous sulfate, tetramethylethylenediamine, 4,4'-azobis (4-cyano Under the condition that base valeric acid), ammonium persulfate and hydrogen peroxide exist, monomer A, monomer B, monomer C, monomer D and inorganic component carry out copolymerization reaction in water, obtain gel; Said gel After chopping, add sodium silicate and sodium pyrophosphate, let stand to swell, dry and pulverize the swollen gel to obtain powder, which is the oil displacement system. The monomers adopted in the invention (all of which are acryloyloxy monomers) have relatively high activity, are easy to prepare high-molecular-weight products, have excellent viscosity-increasing properties, and are used in small amounts. The oil displacement system of the invention is easy to store and transport, and meets the requirements of environmental protection. The raw materials of the method of the invention are easy to obtain, and the preparation process is suitable 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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