CN111607371A - Efficient blockage removing system for polymer flooding injection well, preparation method and application of efficient blockage removing system - Google Patents
Efficient blockage removing system for polymer flooding injection well, preparation method and application of efficient blockage removing system Download PDFInfo
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Abstract
The invention belongs to the technical field of oil-water well production and injection increasing in petroleum industry, and discloses a polymer flooding injection well efficient blockage removing system and application thereof. The polymer flooding injection well efficient blockage removing system comprises 30-60% of an oxidation-reduction system and 40-70% of a gel cluster dispersing agent in percentage by mass. Compared with the traditional oxidation-reduction blockage removal system, the water quality control agent can be prepared and used by water with different mineralization degrees, and has good degradation efficiency on the polymer and the gel cluster thereof under the use concentration of 0.05-5%. The invention aims to provide a high-efficiency blockage removing system for a polymer flooding injection well, which can be used for breaking a gel polymer into a long-chain polymer or enabling the long-chain polymer to be in a stretching state; then under the action of a redox system, bonds of the long-chain polymer are broken to be changed into small molecules, so that the blockage caused by the polymer is relieved, and the injection pressure of the polymer flooding well is remarkably reduced.
Description
Technical Field
The invention belongs to the technical field of oil-water well production increase and injection increase in petroleum industry, relates to a blocking remover blocking removal technology for a polymer flooding injection well in oil extraction engineering of an oil field, and particularly relates to a pressure reduction and injection increase technology for a water injection well taking polyacrylamide and derivatives thereof as oil displacement polymers.
Background
In recent years, with the continuous shortage of world energy and the continuous development of petroleum industry, the tertiary oil recovery technology gradually draws attention of people and makes great progress, and polymer flooding becomes one of the tertiary oil recovery methods with development potential at home and abroad at present due to the characteristics of simple technology, large range of crude oil recovery rate improvement, good economic benefit and the like. Since the 60's of the 20 th century, more than 200 oil fields or blocks have been tested for polymer flooding all over the world, and the polymer flooding technology has become one of the important production increasing technologies for many oil fields at home and abroad. The Chinese polymer flooding technology has been developed rapidly since the 90 s in the 20 th century, has become the world's largest polymer flooding oil-producing country in 1998, and the polymer flooding projects have been correspondingly developed in major oil fields such as Daqing, Shengli, Xinjiang, Jilin, Liaohe, Henan, Jianghan, Dagang and the like, and only Daqing oil field has polymer flooding yield exceeding 1234 ten thousand tons in 2003. But under the action of stratum adsorption, mechanical trapping and the like and the influence of stratum clay expansion and particle migration, polymers are easy to be detained in a porous medium, so that the flow cross section of a pore passage is reduced, the flow resistance is increased, and the permeability is reduced. The polymer is easy to block the stratum due to incomplete dissolution, incompatibility of molecular weight and the pore throat radius of the stratum, denaturation of the polymer solution caused by the influence of the pH, temperature, salinity and shearing force of the stratum and the like. Meanwhile, the polymer flooding injection well is easy to be blocked due to various reasons such as formation water property, solution preparation water property, injection preparation process and the like. At present, the number of polymer injection wells in the Bohai sea oil field reaches more than 30, but the problem of plugging the polymer injection wells becomes more and more prominent in recent years. Reservoir plugging has been a commonly encountered problem in polymer flooding oilfield development.
For the problem, measures such as fracturing, chemical blockage removal and the like are mostly adopted in oil fields at home and abroad, but the blockage caused by polymer flooding is difficult to obtain an ideal blockage removal effect by using the conventional acidification treatments such as a multi-hydrogen acid system, a fluoboric acid system, a biological acid system and the like, and although the blockage of a polymer flooding injection well can be relieved to a certain extent, the problems of unsatisfactory blockage removal and injection increase effects, short effective period and the like generally exist. The adoption of the blocking remover with strong oxidizing property is an effective method for removing the blockage of the polymer flooding injection well, which is recognized at home and abroad at present. Such as nan Yu Ming, etcDevelops FeSO4·7H2O/(NH4)2S2O8The viscosity reduction effect of the redox system on the polyacrylamide aqueous solution has the relative molecular mass of 1.05 × 107Adjusting the pH of a polymer water solution with the hydrolysis degree of 33% and the content of partially hydrolyzed polyacrylamide of 250-2000 mg/L to 5.1, and adding 70mg/L of S2O8 2And 10mg/L of Fe2+After the reaction is carried out for 1 hour at the temperature of 45 ℃, the viscosity reduction rate of the polymer solution can reach more than 90 percent. The viscosity reduction effect of chlorine dioxide, hydrogen peroxide, ammonium persulfate, potassium permanganate, sodium bisulfite, ferrous sulfate and a composite system thereof on polyacrylamide aqueous solution is researched by segmental red and the like. An oxidation type composite blocking remover based on chlorine dioxide developed in the oil field in the eastern Ji province. However, compared with other blockage removal technologies, the redox blockage removal systems have the defects of high safety risk, difficulty in controlling the construction process, unsatisfactory blockage removal effect and the like.
In the prior art, for example, a chinese patent application (application number: CN2012104009218) discloses a preparation method of a polyacrylamide emulsion, wherein Polyacrylamide (PAM) is a water-soluble polymer with the largest use amount at present, and Cationic Polyacrylamide (CPAM) has the characteristics of wide application range, small influence by coexisting salts, and the like, and is widely applied to the operation links of clay anti-swelling, acid thickening, water shutoff and profile control, and the like in the processes of papermaking, metallurgy, mining, printing and dyeing textile, daily chemical industry, industrial water treatment, oil and gas drilling and production. The method is prepared from the following components: inorganic salt, deionized water, a dispersing agent, a cationic monomer, an acrylamide monomer, a masking agent and an initiator thereof; EDTA (ethylene diamine tetraacetic acid disodium salt) is selected as a masking agent, so that the influence of metal ions on the experiment is reduced, and the dosage of the EDTA is 0.001-0.005% of the mass of the nonionic monomer; the initiator system can be an oxidation system, a redox system or a mixture of the initiation systems, APS (ammonium persulfate) and TEA (triethanolamine) are selected to be mixed as the initiator, and the amount of the initiator is 0.002-0.005 percent of the mass of the nonionic monomer. For another example, chinese patent application (application No. CN2014101413073) discloses a resistance reducer for fracturing and a preparation method thereof, including: mixing acrylamide monomers, double-bond-containing hydroxyl nonionic monomers, polyhydroxy nonionic polymer templates, chelating agents, molecular weight regulators and water to obtain an aqueous solution; contacting an organic solvent with an emulsifier to obtain an oil solution; contacting the aqueous solution with the oil solution to obtain a water-in-oil emulsion; under inert atmosphere, the water-in-oil emulsion is contacted with an initiator in batches, polymerization reaction is carried out, and then a mixture obtained by the polymerization reaction is contacted with a phase transfer agent; the hydrophilic-lipophilic balance value of the emulsifier is 4-6, the molecular weight of the polyhydroxy nonionic polymer template is less than 50 ten thousand, the structural formula of the polyhydroxy nonionic polymer template is shown as a formula (I) or a formula (II), and the drag reducer for fracturing prepared by the method is also disclosed. The chelating agent is at least one of disodium ethylene diamine tetraacetate, triethylene pentaacetic acid, citric acid, citrate and polyhydroxyacrylic acid; the initiator is a water-soluble redox system initiator and/or an azo initiator, and the water-soluble redox system contains an oxidant and a reducing agent; the mass ratio of the oxidant to the reducing agent is 5: 1-1: 1; chinese patent application (application number: CN2017105192105) discloses a method for preparing cationic polyacrylamide emulsion by water dispersion polymerization, which comprises the following steps: dissolving a nonionic monomer, a cationic monomer, a dispersion stabilizer, part of inorganic salt and an auxiliary agent in deionized water, stirring in a constant-temperature water bath at 40-70 ℃ to form a homogeneous system, introducing nitrogen to remove oxygen, adding an initiator accounting for 50-80% of the total mass of initiator raw materials, continuously reacting for 3-6 h, adding the rest of the initiator, reacting for 6-12 h, adding the rest of the inorganic salt, and continuously stirring to obtain a cationic polyacrylamide emulsion; the initiator is a redox system, the reducing agent is graphene oxide, and the oxidizing agent is persulfate; the mass ratio of the graphene oxide to the persulfate is 5: 1-1: 5, and the amount of the initiator accounts for 0.01-0.1% of the mass of the monomer system; the masking agent is selected from disodium ethylene diamine tetraacetate; the dosage of the masking agent accounts for 0.1-0.5% of the mass of the nonionic monomer. However, although the prior art described above uses similar substances, the function, structure and performance thereof cannot or better solve the drawbacks of the prior art.
The invention provides a composite chemical blocking remover which is applicable to the blockage of a polymer flooding injection well in onshore and offshore oil fields in order to solve the problems of injection allocation quantity reduction, pressure rise, oil well yield reduction and the like caused by the blockage of the polymer flooding injection well in onshore and offshore oil field polymer flooding oil displacement processes. The blocking remover can thoroughly and efficiently degrade polymers with different concentrations and gels thereof, can effectively remove the blocking of a polymer flooding injection well, has the characteristics of easy storage and transportation, no toxicity, environmental protection, safety and high efficiency, and very meets the operation requirements of onshore and offshore oil fields.
Disclosure of Invention
The invention aims to provide a polymer flooding injection well high-efficiency blockage removing system, a preparation method and application thereof, compared with the traditional oil field polymer blockage removing system, the system has the characteristics of wide water quality mineralization adaptability, high degradation speed, more high degradation effect and the like, and the degradation rate of a polymer and a gel cluster thereof is more than 98%.
The invention provides the following technical scheme:
the efficient blockage removing system for the polymer flooding injection well comprises a redox system (an oxidant and a reducing agent) and a gel cluster dispersing agent, and comprises 30-60% of the redox system and 40-70% of the gel cluster dispersing agent in parts by mass.
Preferably: the molar ratio of the oxidant to the reducing agent in the redox system is 1: 1-2: 1.
preferably: the oxidant in the redox system includes, but is not limited to, Na2S2O8Sodium bromate, NaClO7、H2O2Or mixtures thereof.
Preferably: the reducing agent in the redox system includes, but is not limited to, FeSO4Sodium bisulfite and Na2S2O3、FeCl2Or mixtures thereof.
Preferably: the gel group disintegrating agent comprises hydroxyethylidene diphosphonic acid, disodium ethylene diamine tetraacetate, aminotrimethylene phosphonic acid pentasodium, ethylene diamine tetramethylene phosphonic acid pentasodium salt, diethylenetriamine pentamethylene phosphonic acid xsodium salt, diethylenetriamine pentamethylene phosphonic acid disodium salt or a mixture of the hydroxyethylidene diphosphonic acid, the ethylene diamine tetraacetic acid disodium salt and the aminotrimethylene phosphonic acid pentasodium salt.
Preferably: the mineralization degree range of the injected water is 0-50000 mg/L.
The invention discloses a preparation method and application of a polymer flooding injection well efficient blockage removal system, compared with the prior art, the preparation method has the outstanding characteristics and excellent effects that:
1. compared with the traditional oxidation-reduction system, the high-efficiency blockage removing system for the polymer flooding injection well has higher degradation speed and higher degradation effect, and the blockage removing rate for the blockage of the polymer and gel clusters thereof can reach more than 98%.
2. The gel group dispersing agent is contained in the polymer flooding injection well efficient blockage removing system, the structure of a polymer gel group can be effectively dispersed or a polymer long chain is in a stretching state, the redox system can fully play a role conveniently, and the blockage problem of the polymer injection well can be removed in a short time.
3. The raw materials used in the high-efficiency blockage removing system of the polymer flooding injection well are conventional and can be purchased from the market, and the prepared water has wide mineralization degree and can adapt to blockage removal of polymer-injected oil reservoirs with the temperature of more than 50 ℃.
Drawings
FIG. 1 is a graph showing the degradation rate of a polymer flooding injection well high-efficiency plugging removal system and a redox system to polyacrylamide as a function of time in example 1 of the present invention;
FIG. 2 is a graph showing degradation rate of a polymer flooding injection well high-efficiency plugging removal system on polyacrylamide according to the variation of mineralization degree in example 7 of the present invention;
fig. 3 is a graph showing the degradation rate of the polymer flooding well high-efficiency plugging removal system on polyacrylamide according to the change of temperature in example 8 of the present invention.
Detailed Description
The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art.
Example 1
This example provides a single redox system and a polymer flooding well plugging-removal system with gel cluster breaker added. The redox system used in this example was obtained by adding 25 parts by mass of sodium bromate and sodium bisulfite (molar ratio 1:1) and 75 parts by mass of water to a vessel and mixing them uniformly. The polymer flooding injection well efficient blockage removing system added with the gel cluster dispersing agent is obtained by adding 25 parts by mass of sodium bromate and sodium bisulfite (the molar ratio is 1:1), 25 parts by mass of hydroxyethylidene diphosphonic acid and disodium ethylene diamine tetraacetate (the mass ratio is 7:3) and 50 parts by mass of water into a container, and uniformly stirring and mixing the materials.
40000mg/L of injection water is used for preparing a single oxidation reduction system and a polymer flooding injection well high-efficiency blockage removal system into a mass concentration of 1%; respectively mixing the two polymer unblocking systems and a polymer solution (10000mg/L polyacrylamide) according to the weight ratio of 1: 3, uniformly stirring, reacting at 65 ℃ for different times, and comparing the degradation speed and the degradation rate of the two systems to the polymer solution.
Referring to fig. 1, a graph showing the degradation rate of polyacrylamide by the polymer flooding well high-efficiency plugging removal system and the redox system in example 1 along with time is shown. As is evident from the figure, the HEDP and EDTA-Na are contained at the same contact time2The degradation rate of the high-efficiency blockage removing system for the polymer flooding injection well to polyacrylamide is higher than that of a redox system.
See table 1 for an evaluation table of the degradation effect of the polymer flooding well high-efficiency plugging removal system and the single redox system on polyacrylamide in this example. As shown in the table, HEDP and EDTA-Na were contained2The high-efficiency blockage removing system for the polymer flooding injection well can degrade more than 98 percent of polyacrylamide within 4 hours, and the degradation efficiency is far higher than that of a single redox system.
Example 2
This example provides a polymer flooding injection well high-efficiency unblocking system with gel group dispersant, and the gel group dispersant is hydroxyethylMethylenediphosphonic acid (HEDP) and disodium ethylenediaminetetraacetate (EDTA-Na)2) And mixtures thereof.
25 parts by mass of sodium bromate and sodium bisulfite (molar ratio is 1:1), 25 parts by mass of hydroxyethylidene diphosphonic acid and 50 parts by mass of water are added into a container and stirred and mixed uniformly, so that the polymer flooding injection well high-efficiency blockage removing system (containing HEDP) used in the embodiment can be obtained.
25 parts by mass of sodium bromate and sodium bisulfite (molar ratio is 1:1), 25 parts by mass of disodium ethylene diamine tetraacetate and 50 parts by mass of water are added into a container and stirred and mixed uniformly, so that the high-efficiency blockage removing system (EDTA-Na) for the polymer flooding injection well used in the embodiment can be obtained2)。
25 parts by mass of sodium bromate and sodium bisulfite (molar ratio is 1:1), 25 parts by mass of hydroxyethylidene diphosphonic acid and disodium ethylene diamine tetraacetate (mass ratio is 2:1) and 50 parts by mass of water are added into a container and stirred and mixed uniformly, so that the high-efficiency blockage removing system (HEDP: EDTA-Na) for the polymer flooding injection well used in the embodiment can be obtained2＝2:1)。
Using 40000mg/L injection water to prepare the three polymer flooding injection well high-efficiency blockage removal system into a mass concentration of 1%; respectively mixing the three polymer unblocking systems and a polymer solution (10000mg/L polyacrylamide) according to the weight ratio of 1: 3, stirring uniformly, reacting at 65 ℃ for 4 hours, and comparing the degradation effects of different polymer unblocking systems on polyacrylamide.
See table 2 for a comparison of the degradation effect of the polymer flooding well high-efficiency plugging removal system with different gel group diffusant on polyacrylamide in this example. As can be seen from the data in the table, the degradation rate of polyacrylamide by the redox system containing the gel cluster disperser is higher than that of the single redox system.
Example 3
The case provides a high-efficiency blockage removal system for a polymer flooding injection well containing different redox systems, 25 parts by mass of Na2S2O8And FeSO4(molar ratio is 1:1), 25 parts by mass of hydroxyethylidene diphosphonic acid and disodium ethylene diamine tetraacetate (mass ratio is 7:3), and 50 parts by mass ofAnd water is uniformly mixed to prepare the required polymer flooding injection well efficient blockage removing system.
Except that NaClO is used7And Na2S2O3、H2O2And FeCl2System for substituting Na2S2O8And FeSO4The rest are the same as above.
Example 4
The present example provides a polymer flooding injection well high-efficiency unblocking system added with different gel group diffusants, except that aminotrimethylene pentasodium phosphonate, ethylenediamine tetramethylene pentasodium phosphonate, diethylenetriamine pentamethylene phosphonic acid xsodium salt, diethylenetriamine pentamethylene phosphonic acid disodium salt are used to replace hydroxyethylidene diphosphonic acid and ethylenediamine tetraacetic acid disodium salt, and the rest is the same as example 2.
See table 3 for an evaluation table of the degradation effect of the polymer flooding well high-efficiency plugging removal system containing different redox systems and different gel systems on polyacrylamide in examples 3-4 of the present invention. The degradation rate of the redox system containing the gel cluster dispersant on polyacrylamide is higher than 96%, and the degradation performance of the redox system on polyacrylamide is very good.
Example 5
The embodiment simulates a high-efficiency blockage removal system of a polymer flooding injection well to solve the problem that the polyacrylamide gel is blocked in the profile control and flooding process. A polymer flooding well high-efficiency blockage removal system is prepared according to example 1, and a treatment fluid with the mass concentration of 2% is prepared by using 50000mg/L injection water.
Preparing 10000mg/L polyacrylamide solution, and preparing polyacrylamide gel by using organic chromium; then, 2% of polymer is poured on the gel to drive the injection well to effectively block the well (the addition amount is one third of the gel system), and the change of the gel along with the time and the degradation degree are observed in a water bath at 65 ℃.
Table 4 shows the degradation effect of the polymer flooding injection well high-efficiency plugging removal system on gel clusters in example 5 of the present invention. The polymer flooding injection well high-efficiency blockage removing system has good degradation performance on the cross-linked polyacrylamide gel cluster, and can completely degrade the gel cluster with 2 times of volume within 8 hours.
Example 6
This example simulates Ca at the time of oilfield polymer flooding2+And Mg2+The polymer can generate the blockage removing effect of the sediment blockage. A polymer flooding well high-efficiency blockage removal system is prepared according to example 1, and a treatment fluid with the mass concentration of 1% is prepared by using 50000mg/L injection water.
The displacement experiment was carried out at 65 ℃. First, a core was preheated in a displacement apparatus using prepared simulated water (10000mg/L CaCl)2And MgCl2Solution) is subjected to water flooding, and saturated water is applied to the solution; then, displacing the rock core by using the prepared polyacrylamide polymer solution of 10000mg/L, observing the continuous rise of the displacement pressure, and measuring the stable pressure by using water flooding; injecting 1% of 1PV polymer into the rock core to drive an injection well to efficiently remove the blockage, and standing for reaction for 4 hours; and (5) continuously displacing with the simulated water, measuring the stable pressure of the water, and calculating the pressure reduction rate and the permeability increasing rate after treatment.
Table 5 shows the plugging removal effect of the high-efficiency plugging removal system for polymer flooding injection well on plugging of polymer injection well in this example. The high-efficiency blockage removing system for the polymer flooding injection well has a good improvement effect on permeability damage caused by polyacrylamide blockage, and the pressure reduction rate is greatly improved.
Example 7
The high-efficiency blockage removing system for the polymer flooding injection well prepared by the embodiment is prepared by adopting simulated water with the salinity gradient of 1000mg/L, 3000mg/L, 5000mg/L, 10000mg/L, 30000mg/L and 50000 mg/L. A polymer flooding well high-efficiency plugging removal system was prepared as in example 1, and then a treatment fluid having a mass concentration of 1% was prepared using the above-described simulated water. And (3) mixing the 1% polymer flooding well high-efficiency blockage removal system and a polymer solution (10000mg/L) in a ratio of 1: 3, stirring uniformly, reacting at 65 ℃ for 4 hours, and calculating the degradation rate of the polyacrylamide under water quality with different mineralization degrees.
Fig. 2 is a graph showing the degradation rate of the polymer flooding injection well high-efficiency plugging removal system on polyacrylamide according to the variation of the mineralization degree in the embodiment;
table 6 shows the degradation rate of the polymer flooding well high-efficiency plugging removal system of this example on polyacrylamide with different degrees of mineralization. The high-efficiency blockage removal system for the polymer flooding injection well can be prepared by using 1000-50000mg/L of water, and has no difference on degradation performance of polyacrylamide.
Example 8
The embodiment provides the degradation effect of the polymer flooding well high-efficiency plugging removal system on the polymer at different temperatures. 25 parts by mass of sodium bromate and Na2S2O8Adding sodium bisulfite (molar ratio is 1:1:2), 25 parts by mass of hydroxyethylidene diphosphonic acid and disodium ethylene diamine tetraacetate (mass ratio is 2:1) and 50 parts by mass of water into a container, and stirring and mixing uniformly; then, 30000mg/L of simulated water was used to prepare a treatment solution having a mass concentration of 1%. 1% polymer was driven into the well and the plugging system was effectively unplugged from the polymer solution (10000mg/L) in a ratio of 1: 3, stirring uniformly, reacting at 50 ℃, 60 ℃, 70 ℃, 80 ℃ and 90 ℃ for 4 hours, and calculating the degradation rate.
Fig. 3 is a graph showing the degradation rate of the polymer flooding well high-efficiency plugging removal system on polyacrylamide according to the change of temperature in the example.
Table 7 shows the degradation rate of the polymer flooding well high-efficiency plugging removal system of this example on polyacrylamide at different temperatures. The high-efficiency blockage removing system for the polymer flooding injection well keeps the degradation rate of polyacrylamide to be more than 98% in the temperature range of 50-90 ℃, and the degradation rate is slightly increased along with the temperature rise.
The specification is as shown in tables 1-7:
table 1 table for evaluating degradation effect of example 1 on polyacrylamide
Table 2 table for evaluating degradation effect of example 2 on polyacrylamide
TABLE 3 evaluation of degradation effects of examples 3 to 4 on polyacrylamide
Table 4 table for evaluating the effect of example 5 on micelle degradation reaction
Table 5 example 6 table of effects of field application
TABLE 6 evaluation table of degradation effect of example 7 on polyacrylamide
TABLE 7 evaluation table of degradation effect of example 8 on polyacrylamide
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made without departing from the spirit and scope of the invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (9)
1. A polymer flooding injection well high-efficiency blockage removing system comprises the following components: redox system, gel cluster remover; the composite material is characterized by comprising the following components in percentage by mass: 30-60% of redox system and 40-70% of gel mass disintegrating agent.
2. The system for efficiently removing the blockage of the polymer flooding injection well according to claim 1, wherein the molar ratio of the oxidant to the reductant in the redox system is 1: 1-2: 1.
3. the system of claim 2, wherein the oxidant comprises Na2S2O8Sodium bromate, NaClO7、H2O2Or mixtures thereof.
4. The system of claim 2, wherein the reductant comprises FeSO4Sodium bisulfite and Na2S2O3、FeCl2Or mixtures thereof.
5. The system of claim 1, wherein the gel cluster dispersing agent comprises hydroxyethylidene diphosphonic acid, disodium edetate, pentasodium aminotrimethylenephosphonate, pentasodium ethylenediaminetetramethylenephosphonate, x-sodium diethylenetriaminepentamethylenephosphonate, disodium diethylenetriaminepentamethylenephosphonate, or mixtures thereof.
6. A method for preparing a polymer flooding well high-efficiency plugging removal system according to any one of claims 1-5, which is characterized by comprising the following preparation steps:
step 1: weighing the oxidant and the reducer according to the molar ratio of 1: 1-2: 1.
Step 2: weighing the gel mass disintegrating agent according to the mass ratio of 3: 2-3: 7 based on the total mass of the weighed oxidant and reducer.
And step 3: according to the total mass of the weighed oxidant, the reducer and the gel group disintegrating agent, measuring water with the same mass, adding the water into a container, and starting a stirring device.
And 4, step 4: sequentially adding an oxidant and a reducing agent into a container, and stirring and mixing uniformly; then, adding the gel mass disintegrating agent, and stirring and mixing uniformly.
7. An on-site application method applied to the high-efficiency plugging removal system for the polymer flooding injection well in the oil field oil extraction engineering, which is characterized by comprising the preparation method of the high-efficiency plugging removal system for the polymer flooding injection well of claim 6, and further comprising the following steps: the high-efficiency blockage removal system has the degradation rate of more than 98 percent on the polymer and the gel cluster thereof after reacting with the polymer and the gel cluster thereof for 4 hours.
8. An on-site application method applied to the high-efficiency plugging removal system for the polymer flooding injection well in the oil field oil extraction engineering, which is characterized by comprising the preparation method of the high-efficiency plugging removal system for the polymer flooding injection well of claim 6, and further comprising the following steps: the on-site use concentration of the efficient blockage removing system is 0.05-5%, and the range of the prepared water mineralization degree is 0-50000 mg/L.
9. An on-site application method applied to the high-efficiency plugging removal system for the polymer flooding injection well in the oil field oil extraction engineering, which is characterized by comprising the preparation method of the high-efficiency plugging removal system for the polymer flooding injection well of claim 6, and further comprising the following steps: placing the high-efficiency blockage removing system in a treatment interval, and then closing the well for a period of time; when the pressure at the well head is not reduced any more, the water injection can be continued.
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