Environment-friendly high-permeability blocking removal composition and preparation method thereof

Abstract

The invention belongs to the technical field of oil-water well plug removal, and particularly relates to an environment-friendly high-permeability plug removal composition and a preparation method thereof. The blocking removal composition is prepared from the following raw materials in percentage by mass: 15 to 25 percent of chelating agent, 0.5 to 1 percent of surfactant, 1 to 1.5 percent of coupling agent, 0.5 to 1 percent of clay stabilizer, 0.5 to 1 percent of anti-settling agent and the balance of water. The blockage removal composition can reduce the corrosion rate and improve the corrosion rate and the blockage degradation rate.

Description

Technical Field

[0001] This invention belongs to the field of oil and water well unblocking technology, and particularly relates to an environmentally friendly high-permeability unblocking composition and its preparation method. Background Technology

[0002] For the foreseeable future, water injection will remain the primary method of oilfield development and a key technology for maintaining formation pressure and enhancing oil recovery. However, in this long and complex process, reservoirs inevitably suffer damage from various physical, chemical, and anthropogenic factors, leading to rock pore blockage, a significant decrease in permeability, and consequently, severely impacting well productivity. Specifically, from the drilling stage onward, solid particles in the drilling fluid (such as barite and clay) will infiltrate the shallow formation with the drilling mud, forming dense mud cakes or embedding themselves in pore throats, causing mechanical blockage. Simultaneously, the high alkalinity of the drilling fluid filtrate will trigger the hydration, expansion, and dispersion of clay minerals in the reservoir, further narrowing the seepage channels. During cementing, the cement slurry filtrate is also highly alkaline, and its intrusion will exacerbate the instability of sensitive minerals such as montmorillonite in the reservoir, leading to permanent damage to pore throats. During the perforation process, although the high-speed jet can connect the wellbore with the formation, it will also form a compaction zone around the hole, which will compress the rock pore structure in the area and drastically reduce the permeability. At the same time, the formation debris generated will also participate in the blockage.

[0003] The problems become more complex after entering the water injection development stage. Long-term water injection introduces suspended solid particles, bacteria, and their metabolic products. These impurities are retained and accumulate in the pores, gradually forming physical blockages. Furthermore, the mixing of different water sources (such as formation water and injected water) often results in inorganic scale deposits due to ionic composition mismatch, such as calcium carbonate, barium sulfate, and strontium sulfate. These scales adhere firmly to the pore walls or throats, significantly reducing the effective seepage area. Simultaneously, heavy components in crude oil, such as waxes and asphaltenes, are prone to precipitate and form organic scale under temperature and pressure changes or interactions with injected water. This organic scale intertwines with inorganic scale and impurities, forming mixed scale blockages that are even more difficult to clear. In the later stages of reservoir development, electrochemical corrosion of the downhole tubing and formation minerals produces corrosion products such as rust and ferrous sulfide. These fine particles migrate with the fluid to deeper formations, further exacerbating pore blockage.

[0004] The aforementioned multi-type and multi-causal blockage problems overlap, leading to a continuous increase in water injection pressure and a decrease in injection volume. Consequently, the production of fluids and oil from oil wells declines significantly, severely restricting the stable production and economic benefits of oilfields. Therefore, how to efficiently, sustainably, and environmentally friendly remove complex blockages in deep formations and restore and improve reservoir permeability has become a core technical challenge that must be addressed and resolved in the subsequent development of oilfields. Traditional unblocking agents often have limitations such as insufficient permeability, weak targeting, high environmental pollution risk, or short effective range. Developing a novel unblocking system that can deeply penetrate low-permeability pore throats, efficiently dissolve or disperse various types of blockages, and is environmentally friendly has significant practical significance and application value. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, one of the objectives of the present invention is to provide an environmentally friendly high-permeability unblocking composition that improves the degradation rate of blockages while reducing the corrosion rate.

[0006] One of the objectives of this invention is achieved through the following technical solution: An environmentally friendly, high-permeability unblocking composition, by mass percentage, consists of the following raw materials: chelating agent 15-25%, surfactant 0.5-1%, coupling agent 1-1.5%, clay stabilizer 0.5-1%, anti-settling agent 0.5-1%, and the balance being water; The structural formula of the coupling agent is: .

[0007] Furthermore, the preparation of the coupling agent includes the following steps: (1) L-cysteine ​​and retinol were added to n-heptane, followed by hydrochloric acid solution. After reaction, the mixture was purified to obtain intermediate 1. The structural formula of intermediate 1 is: (2) The intermediate 1 was added to tetrahydrofuran, followed by the addition of hydrogen thiocyanate and N,N-diisopropylethylamine. After the reaction, the mixture was purified to obtain the coupling agent.

[0008] Furthermore, in step (1), the ratio of L-cysteine, retinol, HCl and n-heptane in the hydrochloric acid solution is 1 mmol: (1.2-1.5) mmol: (1.3-1.5) mmol: (6-7) mL; and the concentration of the hydrochloric acid solution is 4-5 mol / L.

[0009] Furthermore, the reaction in step (1) is carried out at a temperature of 95-105°C for 18-24 hours.

[0010] Furthermore, in step (2), the ratio of intermediate 1, hydrogen thiocyanate, N,N-diisopropylethylamine, and tetrahydrofuran is 1 mmol: (1-1.2) mmol: (1-1.2) mmol: (4-5) mL; and the reaction time is 3-5 h.

[0011] Furthermore, the preparation of the anti-settling agent includes the following steps: Gum arabic was added to a water / dimethyl sulfoxide mixture, followed by 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and 4-dimethylaminopyridine. After stirring, cinnamyl alcohol was added, and the mixture was purified after reaction to obtain the anti-settling agent.

[0012] Furthermore, the ratio of gum arabic, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, 4-dimethylaminopyridine, cinnamyl alcohol, and the mixed solution is 1g:(0.08-0.12)g:(0.05-0.08)g:(0.2-0.3)g:(10-11)mL.

[0013] Furthermore, the stirring time is 1-1.5 h; the reaction temperature is 35-45 °C, and the reaction time is 16-24 h.

[0014] Furthermore, the chelating agent is composed of trisodium methylglycine diacetate and sodium citrate in a mass ratio of 1:(1.5-2); the surfactant is dodecyl betaine; and the clay stabilizer is heptadecanylamine ethyl imidazoline quaternary ammonium salt.

[0015] The second objective of this invention is to provide a method for preparing an environmentally friendly, high-permeability unblocking composition that is simple to operate.

[0016] The second objective of this invention is achieved by the following technical solution: The preparation method of the above-mentioned environmentally friendly high-permeability unblocking composition includes the following steps: Add the chelating agent to the water, then add the surfactant, coupling agent, clay stabilizer, and anti-settling agent and mix well.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The unblocking composition of the present invention includes raw materials such as chelating agents, coupling agents, and anti-settling agents, which can reduce the corrosion rate and increase the dissolution rate and the degradation rate of blockages.

[0018] 2. This invention reduces the metal corrosion rate and improves the degradation rate of mixed blockages by adding a coupling agent. Specifically, the coupling agent is synthesized in multiple steps through the condensation reaction of retinol with cysteine ​​carboxyl groups and the nucleophilic addition reaction with hydrogen thiocyanate. Its molecule simultaneously carries polar functional groups such as thiourea and mercapto groups. These polar groups can disrupt the hydrogen bond network between polymer chains, reduce the surface tension of the blockage, and promote the penetration and diffusion of the chelating unblocking agent into the organic scale layer. The interfacial anchoring of thiourea, mercapto groups, and polar groups on the asphaltene surface, along with the steric hindrance effect of the retinol skeleton, inhibits the re-aggregation of asphaltene micelles. The chelating agent, in conjunction with the polymer chain de-entanglement, dissolves and removes the organic scale. Simultaneously, the thiourea and mercapto groups form a dense adsorption film on the metal surface to reduce the corrosion rate, achieving a synergistic effect of unblocking and corrosion prevention.

[0019] 3. This invention improves the dissolution rate by adding an anti-settling agent. Specifically, the anti-settling agent containing aromatic rings utilizes the π-π stacking effect with asphaltene molecules to enhance the dispersion stability of asphaltene, prevent its re-aggregation and blockage, and work synergistically with chelating agents, surfactants, and other components to improve the dissolution and removal effect. Attached Figure Description

[0020] Figure 1 The image shows the infrared spectrum of the anti-settling agent prepared in Example 4, where curve 1 is the infrared spectrum of gum arabic and curve 2 is the infrared spectrum of the anti-settling agent. Detailed Implementation

[0021] The present invention will now be further described with reference to the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments. Specific conditions not specified in the embodiments are performed according to conventional conditions or conditions recommended by the manufacturer. Unless otherwise specified, all reagents or instruments used are conventional products obtained through commercial channels.

[0022] Example 1 Example 1 provides a coupling agent, which is prepared by the following steps: (1) L-cysteine ​​(10 mmol) and retinol (14 mmol) were added to n-heptane (65 mL), stirred evenly, and then 4.5 mol / L hydrochloric acid solution (15 mmol) was added. The mixture was gradually heated to 100 °C and reacted for 20 h. The reaction solution was concentrated, and the residue was refluxed and pulped with a mixed solution of n-hexane / tetrahydrofuran (v / v, 1:4). The mixture was filtered while hot, and the filter cake was dried to obtain intermediate 1. The NMR and mass spectrometry results of intermediate 1 were as follows: 1 HNMR (C 23 H 35NO2S, 400MHz, DMSO): δ8.74(s,2H),6.53(s,4H),6.23(s,1H),5.64-5.62(m,1H),4.75(d,2H),3.78(t,1H),3. 28-3.03(m,2H),2.13(s,6H),1.97(t,2H),1.75-1.73(m,5H),1.54(t,2H),1.48(s,1H),1.03(s,6H);HRMS(ESI + ):[M+H] + The calculation yields 390.24, and the result is 390.20.

[0023] (2) Intermediate 1 (10 mmol) was added to tetrahydrofuran (45 mL), stirred until homogeneous, and then hydrogen thiocyanate (CAS: 36810-87-4, 11 mmol) and N,N-diisopropylethylamine (11 mmol) were added. The mixture was reacted at room temperature for 4 h. The reaction solution was filtered, and the filter cake was dried to obtain the crude product. The crude product was slurried with a mixed solution of n-hexane / tetrahydrofuran (v / v, 1:2), and the filter cake was dried to obtain the coupling agent. The NMR and mass spectrometry results of the coupling agent are as follows: 1 HNMR (C 29 H 44 N2O3S2,400MHz,DMSO): δ9.00(s,1H),7.31(s,1H),6.53(s,4H),6.23(s,1H),5.64-5.62(m,1H),4.75(d,2H),3.80 -3.70(m,3H),3.28-3.03(m,2H),2.13-1.71(m,17H),1.54(t,2H),1.50(s,3H),1.48(s,1H),1.03(s,6H);HRMS(ESI + ):[M] Calculation yields 532.28, and the value is found to be 532.28.

[0024] Example 2 Example 2 provides a coupling agent, which is prepared by the following steps: (1) L-cysteine ​​(10 mmol) and retinol (12 mmol) were added to n-heptane (60 mL), stirred evenly, and then hydrochloric acid solution (13 mmol) with a concentration of 4 mol / L was added. The temperature was gradually raised to 95 °C and reacted for 24 h. The reaction solution was concentrated, and the residue was refluxed and pulped with a mixed solution of n-hexane / tetrahydrofuran (v / v, 1:4). The mixture was filtered while hot, and the filter cake was dried to obtain intermediate 1. The NMR and mass spectrometry results of intermediate 1 were the same as those in Example 1.

[0025] (2) Add intermediate 1 (10 mmol) to tetrahydrofuran (40 mL), stir well, then add hydrogen furfuryl isothiocyanate (10 mmol) and N,N-diisopropylethylamine (10 mmol), and react at room temperature for 3 h; filter the reaction solution, dry the filter cake to obtain crude product, slurry the crude product with a mixed solution of n-hexane / tetrahydrofuran (v / v, 1:2), and dry the filter cake to obtain coupling agent. The NMR and mass spectrometry results of the coupling agent are the same as in Example 1.

[0026] Example 3 Example 3 provides a coupling agent, which is prepared by the following steps: (1) L-cysteine ​​(10 mmol) and retinol (15 mmol) were added to n-heptane (70 mL), stirred evenly, and then hydrochloric acid solution (15 mmol) with a concentration of 5 mol / L was added. The temperature was gradually raised to 105 °C and reacted for 18 h. The reaction solution was concentrated, and the residue was refluxed and pulped with a mixed solution of n-hexane / tetrahydrofuran (v / v, 1:4). The mixture was filtered while hot, and the filter cake was dried to obtain intermediate 1. The NMR and mass spectrometry results of intermediate 1 were the same as those in Example 1.

[0027] (2) Add intermediate 1 (10 mmol) to tetrahydrofuran (50 mL), stir well, then add hydrogen furfuryl isothiocyanate (12 mmol) and N,N-diisopropylethylamine (12 mmol), and react at room temperature for 5 h; filter the reaction solution, dry the filter cake to obtain crude product, slurry the crude product with a mixed solution of n-hexane / tetrahydrofuran (v / v, 1:2), and dry the filter cake to obtain coupling agent. The NMR and mass spectrometry results of the coupling agent are the same as in Example 1.

[0028] Example 4 Example 4 provides an anti-settling agent, which is prepared through the following steps: A mixture of gum arabic, EDCI, DMPA, cinnamyl alcohol, and a mixed solution was prepared in a ratio of 1 g: 0.1 g: 0.06 g: 0.25 g: 10.5 mL. Gum arabic was added to a water / dimethyl sulfoxide mixture (v / v, 3:2), and stirred until homogeneous. Then, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI) and 4-dimethylaminopyridine (DMPA) were added, and the mixture was stirred for 1.2 h. Cinnamyl alcohol was then added, and the reaction was carried out at 40 °C for 20 h. The reaction solution was dialyzed against a water / dimethyl sulfoxide mixture (v / v, 3:2) for 12 h, then against deionized water for 48 h, and finally freeze-dried to obtain an anti-settling agent.

[0029] Example 5 Example 5 provides an anti-settling agent, which is prepared through the following steps: A mixture of gum arabic, EDCI, DMPA, cinnamyl alcohol, and a mixed solution was prepared in a ratio of 1 g: 0.08 g: 0.05 g: 0.2 g: 10 mL. Gum arabic was added to a water / dimethyl sulfoxide mixed solution (v / v, 3:2), and stirred until homogeneous. Then, EDCI and DMPA were added, and the mixture was stirred for 1 h. Cinnamyl alcohol was then added, and the mixture was reacted at 35 °C for 24 h. The reaction solution was dialyzed against a water / dimethyl sulfoxide mixed solution (v / v, 3:2) for 12 h, then against deionized water for 48 h, and finally freeze-dried to obtain an anti-settling agent.

[0030] Example 6 Example 6 provides an anti-settling agent, which is prepared through the following steps: A mixture of gum arabic, EDCI, DMPA, cinnamyl alcohol, and a mixed solution was prepared in a ratio of 1 g: 0.12 g: 0.08 g: 0.3 g: 11 mL. Gum arabic was added to a water / dimethyl sulfoxide mixed solution (v / v, 3:2), and stirred until homogeneous. Then, EDCI and DMPA were added, and the mixture was stirred for 1.5 h. Cinnamyl alcohol was then added, and the mixture was reacted at 45 °C for 16 h. The reaction solution was dialyzed against a water / dimethyl sulfoxide mixed solution (v / v, 3:2) for 12 h, then against deionized water for 48 h, and finally freeze-dried to obtain an anti-settling agent.

[0031] Example 7 Example 7 provides an environmentally friendly high-permeability unblocking composition, which, by mass percentage, consists of the following raw materials: 20% chelating agent, 0.7% dodecyl betaine, 1.2% coupling agent prepared in Example 1, 0.9% heptadecenylamine ethyl imidazoline quaternary ammonium salt, 0.8% anti-settling agent prepared in Example 4, and the balance being water; wherein the chelating agent is composed of trisodium methylglycine diacetate and sodium citrate in a mass ratio of 1:1.8.

[0032] Example 7 also provides a method for preparing the above-mentioned environmentally friendly high-permeability unclogging composition, comprising the following steps: Add the chelating agent to the water, then add dodecyl betaine, the coupling agent prepared in Example 1, heptadecanylamine ethyl imidazoline quaternary ammonium salt, and the anti-settling agent prepared in Example 4, and mix well.

[0033] Example 8 Example 8 provides an environmentally friendly high-permeability unblocking composition, which, by mass percentage, consists of the following raw materials: 15% chelating agent, 0.5% dodecyl betaine, 1% coupling agent prepared in Example 2, 0.5% heptadecenylamine ethyl imidazoline quaternary ammonium salt, 0.5% anti-settling agent prepared in Example 5, and the balance being water; wherein the chelating agent is composed of trisodium methylglycine diacetate and sodium citrate in a mass ratio of 1:1.5.

[0034] Example 8 also provides a method for preparing the above-mentioned environmentally friendly high-permeability unclogging composition, comprising the following steps: Add the chelating agent to the water, then add dodecyl betaine, the coupling agent prepared in Example 2, heptadecanylamine ethyl imidazoline quaternary ammonium salt, and the anti-settling agent prepared in Example 5, and mix well.

[0035] Example 9 Example 9 provides an environmentally friendly high-permeability unblocking composition, which, by mass percentage, consists of the following raw materials: 25% chelating agent, 1% dodecyl betaine, 1.5% coupling agent prepared in Example 3, 1% heptadecenylamine ethyl imidazoline quaternary ammonium salt, 1% anti-settling agent prepared in Example 6, and the balance being water; wherein the chelating agent is composed of trisodium methylglycine diacetate and sodium citrate in a mass ratio of 1:2.

[0036] Example 9 also provides a method for preparing the above-mentioned environmentally friendly high-permeability unclogging composition, comprising the following steps: Add the chelating agent to the water, then add dodecyl betaine, the coupling agent prepared in Example 3, heptadecanylamine ethyl imidazoline quaternary ammonium salt, and the anti-settling agent prepared in Example 6, and mix well.

[0037] Comparative Example 1 The difference between Comparative Example 1 and Example 7 is that the coupling agent prepared in Example 1 is missing.

[0038] Comparative Example 2 The difference between Comparative Example 2 and Example 7 is that the anti-settling agent prepared in Example 4 was replaced with gum arabic.

[0039] Experimental Example 1 The anti-settling agent prepared in Example 4 was analyzed by Fourier transform infrared spectroscopy (FT-IR), and the results are as follows: Figure 1 As shown.

[0040] Figure 1 This is the infrared spectrum of the anti-settling agent prepared in Example 4, where curve a is the infrared spectrum of gum arabic and curve b is the infrared spectrum of the anti-settling agent. (Observation) Figure 1 It is known that: compared to gum arabic, the anti-settling agent has a lower concentration at 1730 cm. -1 The peak is attributed to the stretching vibration of the ester carbonyl group (C=O), indicating that cinnamyl alcohol undergoes an esterification reaction with the carboxyl group of gum arabic to form an ester bond; 1200 cm⁻¹ -1 The peak is attributed to the stretching vibration of the ester group (C–O); 1500 cm⁻¹ -1 The peak is attributed to the stretching vibration of the cinnamyl alcohol benzene ring (C=C).

[0041] Experimental Example 2 The performance of the unblocking compositions obtained in Examples 7-9 and Comparative Examples 1-2 was tested, as follows: Corrosion rate: The corrosion inhibition performance of the unblocking composition was determined according to Q / SY 148-2014 "Technical Requirements for Chemical Descaling Agents for Oilfield Gathering and Transportation Systems". The test temperature was 40℃ and the material was N80 steel sheet. The results are shown in Table 1. Solubility: Weigh a certain amount of the unblocking composition and mix it evenly with distilled water to obtain an aqueous solution of the unblocking composition with a concentration of 3wt%. Then, add 2g of calcium carbonate or magnesium carbonate sample to 100mL of the unblocking composition aqueous solution and shake it evenly at 50℃. Then, place it in a constant temperature incubator at 50℃ for 24h. Take out the sample and filter it with medium-speed qualitative filter paper. Then, dry it at 105℃. Finally, calculate the solubility by the mass difference before and after the experiment. The results are shown in Table 1. Degradation rate of mixed blockage material: A certain amount of the unblocking composition was weighed and mixed evenly with distilled water to obtain an aqueous solution of the unblocking composition with a concentration of 3wt%. The blockage material (composed of 40% crude oil, 8% polyacrylamide, 25% inorganic minerals and 27% water; the crude oil contains 26.9% gum and asphaltene; the inorganic minerals consist of 41% calcium carbonate, 32% magnesium carbonate and 27% clay minerals) was placed in the above aqueous solution of the unblocking composition and reacted for 24 hours. The degradation rate was calculated, and the results are shown in Table 1.

[0042] As shown in Table 1, compared to Example 1, the corrosion rate of the unblocking composition obtained by omitting the coupling agent in Comparative Example 1 increased, while the degradation rate of the mixed blockage decreased. These results indicate that the unblocking composition prepared using the coupling agent of this invention can reduce the metal corrosion rate and increase the degradation rate of the mixed blockage. Analysis reveals that the coupling agent synthesized in this invention through a multi-step process involving the condensation reaction of retinol with cysteine ​​carboxyl groups and the nucleophilic addition reaction with furfuryl isothiocyanate, carries polar functional groups such as thiourea and mercapto groups in its molecule. These polar groups disrupt the hydrogen bond network between polymer chains, reducing the surface tension of the blockage and promoting the penetration and diffusion of the chelating unblocking agent into the organic scale layer. The interfacial anchoring of thiourea, mercapto groups, and polar groups on the asphaltene surface, along with the steric hindrance effect of the retinol skeleton, inhibits the re-aggregation of asphaltene micelles. This, combined with the chelating agent, promotes the deentanglement of polymer chains to dissolve and remove organic scale. Simultaneously, the formation of a dense adsorption film on the metal surface by thiourea and mercapto groups reduces the corrosion rate, achieving a synergistic effect of unblocking and corrosion prevention.

[0043] Compared to Example 1, the dissolution rate of the unblocking composition prepared by replacing the anti-settling agent with gum arabic in Comparative Example 2 was reduced. These results indicate that the unblocking composition prepared using the anti-settling agent of this invention can improve the dissolution rate. Analysis shows that the aromatic ring-containing anti-settling agent utilizes the π-π stacking interaction with asphaltene molecules to enhance the dispersion stability of asphaltene, preventing its re-aggregation and blockage, and synergistically improves the dissolution and removal effect with chelating agents, surfactants, and other components.

[0044] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. An environmentally friendly, high-permeability unblocking composition, characterized in that, It is composed of the following raw materials by mass percentage: chelating agent 15-25%, surfactant 0.5-1%, coupling agent 1-1.5%, clay stabilizer 0.5-1%, anti-settling agent 0.5-1%, and the balance is water; The structural formula of the coupling agent is: 。 2. The environmentally friendly high-permeability unblocking composition according to claim 1, characterized in that, The preparation of the coupling agent includes the following steps: (1) L-cysteine ​​and retinol were added to n-heptane, followed by hydrochloric acid solution. After reaction, the mixture was purified to obtain intermediate 1. The structural formula of intermediate 1 is: (2) The intermediate 1 was added to tetrahydrofuran, followed by the addition of hydrogen thiocyanate and N,N-diisopropylethylamine. After the reaction, the mixture was purified to obtain the coupling agent.

3. The environmentally friendly high-permeability unblocking composition according to claim 2, characterized in that, In step (1), the ratio of L-cysteine, retinol, HCl and n-heptane in the hydrochloric acid solution is 1 mmol: (1.2-1.5) mmol: (1.3-1.5) mmol: (6-7) mL; the concentration of the hydrochloric acid solution is 4-5 mol / L.

4. The environmentally friendly high-permeability unblocking composition according to claim 2, characterized in that, The reaction in step (1) is carried out at a temperature of 95-105℃ for 18-24 hours.

5. The environmentally friendly high-permeability unblocking composition according to claim 2, characterized in that, In step (2), the ratio of intermediate 1, hydrogen thiocyanate, N,N-diisopropylethylamine, and tetrahydrofuran is 1 mmol: (1-1.2) mmol: (1-1.2) mmol: (4-5) mL; the reaction time is 3-5 h.

6. The environmentally friendly high-permeability unblocking composition according to claim 1, characterized in that, The preparation of the anti-settling agent includes the following steps: Gum arabic was added to a water / dimethyl sulfoxide mixture, followed by 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and 4-dimethylaminopyridine. After stirring, cinnamyl alcohol was added, and the mixture was purified after reaction to obtain the anti-settling agent.

7. The environmentally friendly high-permeability unblocking composition according to claim 6, characterized in that, The ratio of the amount of gum arabic, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, 4-dimethylaminopyridine, cinnamyl alcohol, and the mixed solution is 1g:(0.08-0.12)g:(0.05-0.08)g:(0.2-0.3)g:(10-11)mL.

8. The environmentally friendly high-permeability unblocking composition according to claim 6, characterized in that, The stirring time is 1-1.5 h; the reaction temperature is 35-45℃ and the reaction time is 16-24 h.

9. The environmentally friendly high-permeability unblocking composition according to claim 1, characterized in that, The chelating agent is composed of trisodium methylglycine diacetate and sodium citrate in a mass ratio of 1:(1.5-2); the surfactant is dodecyl betaine; and the clay stabilizer is heptadecanylamine ethyl imidazoline quaternary ammonium salt.

10. A method for preparing the environmentally friendly high-permeability unblocking composition according to any one of claims 1-9, characterized in that, Includes the following steps: Add the chelating agent to the water, then add the surfactant, coupling agent, clay stabilizer, and anti-settling agent and mix well.

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