A high-temperature-resistant barite plugging-resistant agent for deep and ultra-deep wells and a preparation method and application thereof

Abstract

The application provides a high-temperature-resistant barite plug removal agent for deep wells and super-deep wells and a preparation method and application thereof. The preparation method of the plug removal agent comprises the following steps: adding hyperbranched polyethyleneimine, an acrylamide monomer, an anionic monomer and a polyoxyethylene ether monomer into deionized water to obtain a monomer solution; after the pH of the monomer solution is adjusted to 5-9, nitrogen gas is used to remove oxygen, then the temperature is increased to a reaction temperature, an initiator is added, and a thermal polymerization reaction is initiated; after the reaction is completed, vacuum drying and crushing are performed to obtain a high-temperature-resistant hyperbranched polymer dispersant; the high-temperature-resistant hyperbranched polymer dispersant, an amino polycarboxylic acid chelating agent and a synergist are uniformly mixed and added into deionized water to obtain a plug removal agent aqueous solution, and then the pH of the system is adjusted to 9-11 to obtain the plug removal agent. The barite plug removal agent has good high-temperature resistance and is suitable for barite plug removal in high-temperature deep wells with a temperature of 90 DEG C-200 DEG C, and has excellent plug removal performance.

Description

TECHNICAL FIELD

[0001] The application provides a high-temperature-resistant barite plugging remover for deep and ultra-deep wells and a preparation method and application thereof, and belongs to the technical field of oil field chemicals. BACKGROUND

[0002] With the increasing exploration and development of deep and ultra-deep oil and gas fields, the number of drilling operations in deep and ultra-deep wells continues to rise. During the drilling of such deep wells, high formation pressure becomes a factor that cannot be ignored, which requires the addition of heavy materials to the drilling fluid to increase its density, thereby achieving a state of balance with the formation pressure and effectively preventing safety accidents such as well kick and blowout. Barite, as a commonly used weighting material for high-density drilling fluid, is prone to invade the reservoir through cracks during use, causing reservoir pollution and affecting oil and gas production and economic benefits.

[0003] In recent years, as the use density of barite as a weighting material in drilling fluid gradually decreases, the physical sedimentation phenomenon caused by density differences during drilling fluid circulation intensifies, especially after a period of production, the settling speed of barite increases with time, not only easily plugging the formation, but also the content of barite in the mud cake generated by the loss of drilling fluid to the formation also increases, often accompanied by associated minerals, causing damage to the reservoir near the wellbore. Under high temperature and high pressure conditions, the properties of barite are very stable, and conventional acidizing plugging removal measures are difficult to dissolve barite plugs, which can easily cause long-term plugging of oil and gas channels, reducing the permeability of the near-wellbore zone, which seriously affects our correct identification of oil and gas layers, causing misjudgment of oil and gas production capacity, thereby reducing the recovery rate of oil fields and affecting economic benefits.

[0004] Chinese patent document CN114539463A provides a barite chelating agent plugging removal material and a preparation method thereof, which can form a chelate with barium ions in barite to achieve plugging removal of the barite plugging layer in the reservoir, but its dissolution rate at 170℃ is only 14.5%. Chinese patent document CN118620589A uses diethylene triamine pentaacetic acid as the main chelating agent, potassium hydroxide as the pH regulator, and ethylenediaminetetraacetic acid and nitrilotriacetic acid as the synergistic agent to develop a high-temperature oil and gas well barite chelating plugging removal agent composition, which has a dissolution rate of 74% at 160℃, but the dissolution rate at 180℃ is reduced to 57%, indicating that the dissolution rate at high and ultra-high temperatures needs to be further improved. Chinese patent document CN117821044A provides a neutral plugging removal agent by combining tetrazole quaternary ammonium salt, carboxylate-sulfonate-acrylate terpolymer, surfactant, clay stabilizer, and pH regulator, which has a barite dissolution rate of more than 80% at 90℃, but the dissolution rate in high-temperature and ultra-high-temperature (>180℃) environments has not been measured.

[0005] In summary, the current barite plug remover has small dissolution amount and low effective substance content in high temperature environment, therefore, it is urgent to develop a high temperature resistant barite plug remover for deep and ultra-deep wells by a new preparation method, and to support safe, efficient and economic drilling of deep and ultra-deep wells. SUMMARY

[0006] In view of the deficiencies of the prior art, especially the technical problem of low dissolution rate of the existing barite plug remover in deep high temperature environment, the application provides a high temperature resistant barite plug remover for deep and ultra-deep wells and a preparation method and application thereof.

[0007] To achieve the above-mentioned purpose, the technical scheme of the application is as follows:

[0008] A preparation method of a high temperature resistant barite plug remover for deep and ultra-deep wells, comprising the following steps:

[0009] (1) adding hyperbranched polyethylene imine, acrylamide monomer, anionic monomer and polyoxyethylene ether monomer into deionized water to obtain a monomer solution; adjusting the pH of the monomer solution to 5-9, then removing oxygen by nitrogen blowing, and then heating to a reaction temperature, adding an initiator, and heat-initiating a polymerization reaction; after the reaction is completed, vacuum drying and crushing to obtain a high temperature resistant hyperbranched polymer dispersant;

[0010] (2) mixing the high temperature resistant hyperbranched polymer dispersant obtained in step (1), an amino polycarboxylic acid chelating agent and a synergist uniformly to obtain a plug remover composition, adding the plug remover composition into deionized water to obtain a plug remover aqueous solution, and then adjusting the pH of the system to 9-11 to obtain a high temperature resistant barite plug remover for deep and ultra-deep wells.

[0011] According to the application, preferably, the number average molecular weight of the hyperbranched polyethylene imine in step (1) is 800-1800 g / mol.

[0012] According to the application, preferably, the acrylamide monomer in step (1) is methyl acrylamide (MAM) or N,N-dimethyl acrylamide (DMAA).

[0013] According to the application, preferably, the anionic monomer in step (1) is 2-acrylamido-2-methylpropanesulfonic acid (AMPS) and / or sodium styrene sulfonate (SSS).

[0014] According to the application, preferably, the polyoxyethylene ether monomer in step (1) is one or a combination of more than two of methylalkyl polyoxyethylene ether (TPEG), allyl polyoxyethylene ether (APEG), and polyethylene glycol monomethyl ether (MPEG); the methylalkyl polyoxyethylene ether is TPEG-800, TPEG-1000, or TPEG-2400; the allyl polyoxyethylene ether is APEG-600, APEG-700, APEG-800, or APEG-1000; and the polyethylene glycol monomethyl ether is MPEG-350, MPEG-400, MPEG-450, MPEG-500, MPEG-750, or MPEG-1000.

[0015] According to the application, preferably, the mass ratio of the acrylamide monomer, the anionic monomer, and the polyoxyethylene ether monomer in step (1) is 1-7:1-2:1-2, and more preferably 3-5:1-2:1-2; and the total mass fraction of the monomer solution is 10-40%, and more preferably 15-20%; the total mass of the monomers refers to the sum of the masses of the acrylamide monomer, the anionic monomer, and the polyoxyethylene ether monomer.

[0016] According to the application, preferably, the mass ratio of the hyperbranched polyethyleneimine to the total mass of the acrylamide monomer, the anionic monomer, and the polyoxyethylene ether monomer in step (1) is 0.1-0.25:1.

[0017] According to the application, preferably, in step (1), the pH of the monomer solution is adjusted to 5-9 using a NaOH aqueous solution with a mass fraction of 20-30%.

[0018] According to the application, preferably, the initiator in step (1) is cerium ammonium nitrate (CAN); and the mass ratio of the initiator to the total mass of the acrylamide monomer, the anionic monomer, and the polyoxyethylene ether monomer is 0.01-0.05:1, and more preferably 0.03-0.04:1.

[0019] According to the application, preferably, the reaction temperature in step (1) is 30-80°C, and more preferably 50-70°C; and the polymerization time is 2-6 h, and more preferably 3-5 h.

[0020] According to the application, preferably, the temperature of the vacuum drying in step (1) is 30-70°C, and more preferably 40-60°C; and the vacuum drying time is 3-7 h, and more preferably 4-6 h.

[0021] According to the application, preferably, the amino polycarboxylic acid chelating agent in step (2) is a combination of two of diethylenetriamine pentaacetic acid (DTPA), ethylenediaminetetraacetic acid (EDTA), and hydroxyethylethylenediaminetriacetic acid (HEDTA).

[0022] According to the application, preferably, the synergist in step (2) is a mixture of ethylenediaminetetraacetic acid and nitrilotriacetic acid, and the mass ratio of ethylenediaminetetraacetic acid to nitrilotriacetic acid in the mixture is 1-2:1-2, and further preferably 1:1.

[0023] According to the application, preferably, the mass ratio of the anti-high-temperature hyperbranched polymer dispersant, the aminopolycarboxylic acid chelating agent and the synergist in step (2) is 1.5-2:1.5-2:1.

[0024] According to the application, preferably, the mass concentration of the plugging remover composition in the aqueous solution of the plugging remover in step (2) is 10-40wt%.

[0025] According to the application, preferably, the pH of the monomer solution is adjusted to 9-11 by using a 20-30wt% aqueous NaOH solution in step (2).

[0026] The application further provides an anti-high-temperature barite plugging remover for deep wells and ultra-deep wells, which is prepared by the above preparation method.

[0027] According to the application, the anti-high-temperature barite plugging remover is used for plugging removal of barite.

[0028] The technical features and advantages of the application are as follows:

[0029] 1. The preparation process of the barite plugging remover is simple, the raw materials are easy to obtain, the synthesis temperature and time are easy to control, the obtained plugging remover has a low cost, is convenient for transportation, has a simple use method, can be mixed on line, and is suitable for large-scale use in oil fields.

[0030] 2. The anti-high-temperature hyperbranched polymer dispersant is added to the plugging remover, which can effectively reduce the interaction force between barite particles, prevent the agglomeration and sedimentation of the barite particles, improve the dispersion stability of the barite particles in the plugging remover, make the plugging remover fully contact with the barite particles, and improve the plugging efficiency.

[0031] 3. The barite plugging remover contains the aminopolycarboxylic acid chelating agent, has a large amount of dissolved barite and a high dissolution efficiency, has a good high-temperature resistance, and is suitable for barite plugging removal in high-temperature deep wells at 90℃-200℃.

[0032] 4. The carboxyl groups in the plugging remover can achieve a high removal rate of associated minerals generated by the sedimentation of barite, and the high stability constant of the plugging remover can effectively prevent the ion exchange between the barium ion chelate in the plugging remover and rock minerals, does not harm the original skeleton structure of the reservoir, and greatly improves the recovery value of the permeability of the near-wellbore zone of the oil field. DETAILED DESCRIPTION

[0033] The present invention will be further described below through specific embodiments, but is not limited thereto.

[0034] Unless otherwise specified, the experimental methods described in the examples are conventional methods; the reagents and materials used are commercially available unless otherwise specified.

[0035] Example 1

[0036] A method for preparing a high-temperature resistant barite unblocking agent for deep and ultra-deep wells includes the following steps:

[0037] (1) Synthesis of high-temperature resistant hyperbranched polymer dispersants

[0038] 5g of N,N-dimethylacrylamide (DMAA), 2g of 2-acrylamido-2-methylpropanesulfonic acid (AMPS), 2g of polyethylene glycol monomethyl ether (MPEG-400), and 1.35g of hyperbranched polyethyleneimine (number average molecular weight of 800g / mol) were dissolved in 45g of deionized water to obtain a monomer solution. Under stirring, a 25% NaOH aqueous solution was slowly added dropwise (1 drop / s) to the obtained monomer solution to adjust the pH value of the monomer solution to 8, resulting in a mixed reaction solution. The obtained mixed reaction solution was deoxygenated under nitrogen protection for 30 min, then heated to 60℃, and 0.27g of cerium ammonium nitrate (CAN) initiator was added. The polymerization reaction was carried out at 60℃ for 5 h. After the reaction was completed, the obtained product was dried in a vacuum drying oven at 60℃ for 5 h and then pulverized to obtain a high-temperature resistant hyperbranched polymer dispersant.

[0039] (2) Preparation of high-temperature resistant barite unblocking agent

[0040] High-temperature resistant hyperbranched polymer dispersant, amino polycarboxylic acid chelating agent, and synergist were mixed evenly in a mass ratio of 1.5:1.5:1 to obtain a blockage unblocking agent composition. The obtained blockage unblocking agent composition was added to deionized water to prepare a blockage unblocking agent aqueous solution with a mass concentration of 15wt%. Then, the pH of the system was adjusted to 10 using a 25% NaOH aqueous solution to obtain a high-temperature resistant barite blockage unblocking agent for deep and ultra-deep wells.

[0041] The aminopolycarboxylic acid chelating agent is a composition of ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DTPA), wherein the mass ratio of EDTA to DTPA is 1:1.

[0042] The synergist is a composition of ethylenediaminetetraacetic acid (EDTA) and nitric acid, wherein the mass ratio of EDTA to nitric acid is 1:1.

[0043] Example 2

[0044] A preparation method of a high-temperature-resistant barite plug-removing agent for deep and ultra-deep wells is as described in Embodiment 1, except that the mass concentration of the plug-removing agent aqueous solution in step (2) is 10 wt%.

[0045] Embodiment 3

[0046] A preparation method of a high-temperature-resistant barite plug-removing agent for deep and ultra-deep wells is as described in Embodiment 1, except that the mass concentration of the plug-removing agent aqueous solution in step (2) is 20 wt%.

[0047] Embodiment 4

[0048] A preparation method of a high-temperature-resistant barite plug-removing agent for deep and ultra-deep wells is as described in Embodiment 1, except that the mass concentration of the plug-removing agent aqueous solution in step (2) is 25 wt%.

[0049] Embodiment 5

[0050] A preparation method of a high-temperature-resistant barite plug-removing agent for deep and ultra-deep wells is as described in Embodiment 1, except that the mass concentration of the plug-removing agent aqueous solution in step (2) is 30 wt%.

[0051] Embodiment 6

[0052] A preparation method of a high-temperature-resistant barite plug-removing agent for deep and ultra-deep wells is as described in Embodiment 1, except that the mass concentration of the plug-removing agent aqueous solution in step (2) is 40 wt%.

[0053] Embodiment 7

[0054] A preparation method of a high-temperature-resistant barite plug-removing agent for deep and ultra-deep wells is as described in Embodiment 1, except that equal mass of methacrylamide (MAM) is used instead of N,N-dimethylacrylamide (DMAA) in step (1), and other conditions and component proportions are the same as in Embodiment 1.

[0055] Embodiment 8

[0056] A preparation method of a high-temperature-resistant barite plug-removing agent for deep and ultra-deep wells is as described in Embodiment 1, except that the amino polycarboxylic acid chelating agent in step (2) is a combination of diethylenetriamine pentaacetic acid (DTPA) and hydroxyethyl ethylenediamine triacetic acid (HEDTA), and the mass ratio of diethylenetriamine pentaacetic acid (DTPA) to hydroxyethyl ethylenediamine triacetic acid (HEDTA) is 1:1.

[0057] Comparative Example 1

[0058] A preparation method of a barite plug-removing agent for deep and ultra-deep wells is as described in Embodiment 1, except that the amount of polyethylene glycol monomethyl ether (MPEG) added in step (1) is 0 g.

[0059] Comparative Example 2

[0060] A preparation method of the barite plug remover for deep and ultra-deep wells was as described in Example 1, except that the amount of the anti-high-temperature hyperbranched polymer dispersant added in step (2) was 0 g.

[0061] Comparative Example 3

[0062] A preparation method of the barite plug remover for deep and ultra-deep wells was as described in Example 1, except that the amount of the synergist added in step (2) was 0 g.

[0063] Comparative Example 4

[0064] A preparation method of the barite plug remover for deep and ultra-deep wells was as described in Example 1, except that equal mass of ammonium persulfate (APS) was used instead of cerium ammonium nitrate (CAN) in step (1), and other conditions and component ratios were the same as in Example 1.

[0065] Comparative Example 5

[0066] A preparation method of the barite plug remover for deep and ultra-deep wells was as described in Example 1, except that N,N-dimethylacrylamide (DMAA) was not added in step (1).

[0067] Comparative Example 6

[0068] A preparation method of the barite plug remover for deep and ultra-deep wells was as described in Example 1, except that 2-acrylamido-2-methylpropanesulfonic acid (AMPS) was not added in step (1).

[0069] Comparative Example 7

[0070] A preparation method of the barite plug remover for deep and ultra-deep wells was as described in Example 1, except that equal mass of acrylamide (AM) was used instead of N,N-dimethylacrylamide (DMAA) in step (1), and other conditions and component ratios were the same as in Example 1.

[0071] Comparative Example 8

[0072] A preparation method of the barite plug remover for deep and ultra-deep wells was as described in Example 1, except that equal mass of sodium vinyl sulfonate (VS) was used instead of 2-acrylamido-2-methylpropanesulfonic acid (AMPS) in step (1), and other conditions and component ratios were the same as in Example 1.

[0073] Comparative Example 9

[0074] A preparation method of the barite plugging remover for deep and ultra-deep wells is as described in Embodiment 1, except that in step (2), the high-temperature-resistant hyperbranched polymer dispersant, the amino polycarboxylic acid chelating agent, and the synergist are mixed uniformly at a mass ratio of 1:1:1, and other conditions and component ratios are the same as in Embodiment 1.

[0075] Comparative Example 10

[0076] A preparation method of the barite plugging remover for deep and ultra-deep wells is as described in Embodiment 1, except that in step (2), the high-temperature-resistant hyperbranched polymer dispersant is replaced by an equal amount of a commonly used polycarboxylate dispersant (polyacrylic acid (PAA)), and other conditions and component ratios are the same as in Embodiment 1.

[0077] Test Example 1

[0078] Each embodiment and comparative example is evaluated according to the following method

[0079] Evaluation experiment method for high-temperature static barite dissolution rate

[0080] 1. Main instruments and equipment

[0081] a) High-temperature roller furnace: high-temperature roller heating furnace for drilling fluid according to GB / T 16783.1-2006 standard, temperature control range 0-200℃, precision ±5℃;

[0082] b) High-temperature aging tank: stainless steel material;

[0083] c) Electric heating constant temperature drying box: temperature control range 0-200℃, temperature control sensitivity ±2℃;

[0084] d) Rapid quantitative filter paper: diameter 15cm;

[0085] e) Electronic balance: sensitivity 0.001g;

[0086] f) Funnel: diameter 15cm.

[0087] 2. Main reagents and materials

[0088] a) Barite powder: analytical pure barium sulfate;

[0089] b) Deionized water: laboratory deionized water according to GB / T 6682-2008 standard;

[0090] 3. Barite dissolution rate test method

[0091] a) Take 100mL of the plugging remover prepared in each embodiment and comparative example, and add accurately weighed barium sulfate (2g, denoted as m1) to the plugging remover, and mix uniformly.

[0092] b) The mixed solution obtained in step (a) is added to the high-temperature aging tank and placed in a static condition at a temperature of 150°C, 180°C and 200°C for reaction, and the reaction time is 16h;

[0093] c) After the dissolution reaction is completed, the aging tank is taken out of the roller furnace, and when it is cooled to room temperature, the sealing cover is opened, and the liquid of the plug remover is taken out;

[0094] d) The quantitative filter paper is placed in a 120°C oven and dried to constant weight (its mass is recorded as m2);

[0095] e) The quantitative filter paper is used to filter the plug remover liquid after the dissolution reaction with a funnel, and the residual barite that is not dissolved is washed with test water until the pH value of the filtrate is 7;

[0096] f) The residue is placed in a 120°C oven together with the filter paper and dried to constant weight (its mass is recorded as m3);

[0097] g) The dissolution rate of barite is calculated.

[0098] 4. Dissolution rate result determination

[0099]

[0100] In the formula:

[0101] η - dissolution rate, %; m1 - mass of barium sulfate before the test, g; m2 - mass of quantitative filter paper, g; m3 - mass of filter paper + barium sulfate after the test, g.

[0102] The dissolution rate results of the plug remover samples of the examples and comparative examples at 150°C, 180°C and 200°C for 16h of reaction time are shown in Table 1.

[0103] Table 1 Dissolution rate determination results of plug removers at 150°C, 180°C and 200°C

[0104]

[0105]

[0106]

[0107] As can be seen from Table 1, it can be obtained by Examples 1-8 that the barite plug removal agent prepared by mixing the anti-high-temperature hyperbranched polymer dispersant, the amino polycarboxylic acid chelating agent and the synergist has good plug removal efficiency at high temperature, and the dissolution rate can reach 80% or more. The concentration of the plug removal agent composition has a significant effect on the dissolution efficiency, and different formulations of the plug removal agent have their own optimal dissolution concentration due to the difference in molecular structure. It can be obtained from Examples 1-6 that the dissolution efficiency is best when the concentration of the plug removal agent is 15%. Under high temperature conditions, the dissolution rate of the plug removal agent can basically remain at 80% or more, which shows good high-temperature resistance. By comparing the dissolution rate data at different temperatures, the dissolution rate of barite at 180°C is relatively high, which can be regarded as the optimal use temperature of the plug removal agent of the present application. At this temperature, the dissolution rate of barite in some examples can reach more than 92%.

[0108] By comparing the data of the examples and the comparative examples, it can be seen that in Comparative Example 1, polyethylene glycol monomethyl ether (MPEG) is not contained, so that the degree of branching of the hyperbranched polymer is reduced, and the temperature resistance is reduced; in Comparative Example 2, the anti-high-temperature hyperbranched polymer dispersant is not contained, so that the molecular weight of the linear polymer in the plug removal agent is large, the polymer chain is easy to degrade at high temperature, the temperature resistance is poor, and the dissolution rate of the plug removal agent is greatly reduced; in Comparative Example 3, the synergist is not contained, so that the wettability of the plug removal agent is reduced, the clay particles re-agglomerate, and the plug removal efficiency is reduced; in Comparative Example 4, ammonium persulfate (APS) is used instead of cerium ammonium nitrate (CAN) of the present application, which cannot form the redox initiation system of cerium ammonium nitrate and hydroxyl, thereby hindering the initiation of the hyperbranched polymer chain, generating more linear polymer network structure, and the temperature resistance is poor; in Comparative Example 5, N,N-dimethyl acrylamide monomer is not contained, so that the flowability and dispersibility of the plug removal agent at high temperature are reduced, and the plug removal effect is poor; in Comparative Example 6, the anti-high-temperature anionic hydration monomer is not contained, so that the clay particle aggregation effect is obvious at high temperature, and the plug removal performance is deteriorated; in Comparative Example 7, acrylamide (AM) is directly used instead of N,N-dimethyl acrylamide (DMAA), so that the polymerization degree of the hyperbranched polymer is reduced, and the temperature resistance is reduced; in Comparative Example 8, sodium vinyl sulfonate (VS) is used instead of 2-acrylamido-2-methylpropanesulfonic acid (AMPS), so that the molecular chain is easy to degrade in high temperature environment, and the plug removal performance is invalid. In Comparative Example 9, the ratio of the dispersant, the chelating agent and the synergist is changed, and the plug removal performance is reduced compared with Example 1, which shows that the ratio of the three has an important influence on the performance of the plug removal agent. In Comparative Example 10, the commonly used polycarboxylate dispersant is used instead of the anti-high-temperature hyperbranched polymer dispersant of the present application, and the dissolution rate of the plug removal agent is lower than that of Example 1, which highlights the advantage of the dispersant of the present application in improving the performance of the plug removal agent.

[0109] In summary, in view of the problem of reservoir damage caused by high-density drilling fluid barite invasion in high-pressure reservoir, a high-efficiency dissolution and plugging removal agent with high temperature resistance and dissolution rate of up to 92% is developed under the synergistic effect of high-temperature resistant hyperbranched polymer dispersant, amino polycarboxylic acid chelating agent and synergist. The plugging removal agent has high active content, simple production process, convenient storage and transportation, and high cost performance, and is a high-temperature oil and gas well barite plugging removal agent that can efficiently remove barite plugs.

Claims

1. A method for preparing a high-temperature resistant barite plug remover for deep and ultra-deep wells, comprising the following steps: (1) adding hyperbranched polyethyleneimine, acrylamide monomer, anionic monomer and polyoxyethylene ether monomer into deionized water to obtain a monomer solution; adjusting the pH of the monomer solution to 5-9, removing oxygen by nitrogen blowing, then increasing the temperature to the reaction temperature, adding an initiator and initiating the polymerization reaction; after the reaction, vacuum drying and crushing to obtain a high-temperature resistant hyperbranched polymer dispersant; the acrylamide monomer is methyl acrylamide or N, N-dimethyl acrylamide; the anionic monomer is 2-acrylamido-2-methylpropanesulfonic acid and / or sodium styrene sulfonate; the polyoxyethylene ether monomer is one or a combination of two or more of methyl alkenyl polyoxyethylene ether, allyl polyoxyethylene ether and polyethylene glycol monomethyl ether; (2) mixing the high-temperature resistant hyperbranched polymer dispersant obtained in step (1), amino polycarboxylic acid chelating agent and synergist uniformly to obtain a plug remover composition, adding the plug remover composition into deionized water to obtain a plug remover aqueous solution, then adjusting the pH of the system to 9-11 to obtain a high-temperature resistant barite plug remover for deep and ultra-deep wells; the amino polycarboxylic acid chelating agent is a combination of two of diethylenetriamine pentaacetic acid, ethylenediaminetetraacetic acid and hydroxyethyl ethylenediamine triacetic acid; the synergist is a mixture of ethylenediaminetetraacetic acid and nitrilotriacetic acid. In step (1), the number average molecular weight of the hyperbranched polyethyleneimine is 800-1800 g / mol; the methyl alkenyl polyoxyethylene ether is TPEG-800, TPEG-1000 or TPEG-2400; the allyl polyoxyethylene ether is APEG-600, APEG-700, APEG-800 or APEG-1000; the polyethylene glycol monomethyl ether is MPEG-350, MPEG-400, MPEG-450, MPEG-500, MPEG-750 or MPEG-1000. In step (1), the mass ratio of the acrylamide monomer, the anionic monomer and the polyoxyethylene ether monomer is 1-7:1-2:1-2; the total mass fraction of the monomer solution is 10-40%; the total mass of the monomers refers to the sum of the mass of the acrylamide monomer, the anionic monomer and the polyoxyethylene ether monomer. In step (1), the mass ratio of the acrylamide monomer, the anionic monomer and the polyoxyethylene ether monomer is 3-5:1-2:1-2; the total mass fraction of the monomer solution is 15-20%. In step (1), the mass ratio of the hyperbranched polyethyleneimine to the total mass of the acrylamide monomer, the anionic monomer and the polyoxyethylene ether monomer is 0.1-0.25:

1. In step (1), the pH of the monomer solution is adjusted to 5-9 using a NaOH aqueous solution with a mass fraction of 20-30%; the initiator is cerium ammonium nitrate; the mass ratio of the initiator to the total mass of the acrylamide monomer, the anionic monomer and the polyoxyethylene ether monomer is 0.01-0.05:1; the reaction temperature is 30-80℃; and the polymerization reaction time is 2-6 h. ​ ​ 2. The method for preparing the high temperature resistant barite plug remover for deep and ultra-deep wells according to claim 1, characterized in that, ​ ​ 3. The preparation method of the high-temperature resistant barite unblocking agent for deep and ultra-deep wells according to claim 1, characterized in that, ​ 4. The preparation method of the high-temperature resistant barite unblocking agent for deep and ultra-deep wells according to claim 3, characterized in that, ​ 5. The preparation method of the high-temperature resistant barite unblocking agent for deep and ultra-deep wells according to claim 1, characterized in that, ​ 6. The preparation method of the high-temperature resistant barite unblocking agent for deep and ultra-deep wells according to claim 1, characterized in that, ​ ​ ​ The temperature of the vacuum drying is 30-70℃; the time of the vacuum drying is 3-7h.

7. The preparation method of the high-temperature resistant barite unblocking agent for deep and ultra-deep wells according to claim 1, characterized in that, The mass ratio of the initiator to the total mass of the acrylamide monomer, the anionic monomer and the polyoxyethylene ether monomer in step (1) is 0.03-0.04:1; The reaction temperature is 50-70℃; the time of the polymerization reaction is 3-5h; The temperature of the vacuum drying is 40-60℃; the time of the vacuum drying is 4-6h.

8. The preparation method of the high-temperature resistant barite unblocking agent for deep and ultra-deep wells according to claim 1, characterized in that, The mass ratio of ethylenediaminetetraacetic acid to nitrilotriacetic acid in the mixture in step (2) is 1-2:1-2.

9. The preparation method of the high-temperature resistant barite unblocking agent for deep and ultra-deep wells according to claim 1, characterized in that, The mass ratio of the anti-high-temperature hyperbranched polymer dispersant, the amino polycarboxylic acid chelating agent and the synergist in step (2) is 1.5-2:1.5-2:

1.

10. The method for preparing the high temperature resistant barite plug remover for deep and ultra-deep wells according to claim 1, characterized in that, The mass concentration of the plugging remover composition in the aqueous solution of the plugging remover in step (2) is 10-40wt%; The pH of the monomer solution is adjusted to 9-11 using the aqueous NaOH solution with a mass fraction of 20-30% in step (2).

11. A high temperature resistant barite plug breaking agent for deep and ultra-deep wells, characterized in that, The plugging remover is prepared by the preparation method of claim 1.

12. The use of the anti-high-temperature barite plugging remover for deep well and ultra-deep well of claim 11 for the plugging removal of barite.

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