Slow-release gel breaking rod for offshore up-regulation flooding operation as well as preparation method and adding method of slow-release gel breaking rod

Abstract

The invention belongs to the technical field of oilfield chemistry, and particularly relates to a slow-release gel breaking rod for offshore up-regulation flooding operation as well as a preparation method and an adding method of the slow-release gel breaking rod. The slow-release gel breaking stick for the offshore up-regulation flooding operation, provided by the invention, comprises a gel breaker component which comprises an oxidized gel breaker and a buffering agent; the coating material is coated outside the gel breaker component, and the coating material is formed by melting and blending a plurality of water-soluble resins. Compared with a liquid medicament using mode, the slow-release gel breaking stick for the offshore up-regulation flooding operation has the advantages that the occupied space is extremely small, and the problems that conventional gel breaking solution injection equipment is large in occupied area and long in operation window waiting time are solved; compared with a granular slow-release gel breaker, the slow-release gel breaker is simpler and more convenient to add and does not need to be carried by a high-viscosity polymer solution.

Description

Technical Field

[0001] This invention belongs to the field of oilfield chemical technology, specifically relating to a slow-release colloid breaking rod for offshore destabilization operations, its preparation method, and its application method. Background Technology

[0002] As development deepens, the water cut in offshore oilfields is rising rapidly, making the situation for stabilizing and increasing oil production severe. Profile control, water shut-off, and other technologies have become important production enhancement measures. These technologies utilize polymer gels to block water channels, reduce water cut, and thus improve oil recovery. However, after these operations, excessive blockage in the near-wellbore area can easily occur, causing wellhead pressure to approach the pressure limit, affecting subsequent production. In some high-pressure well groups, complete profile control and water shut-off measures cannot be completed, forcing the use of gel breaking operations.

[0003] Commonly used breaker solutions on offshore platforms are highly oxidizing and cannot be directly applied using conventional profile control and displacement equipment. Corrosion-resistant equipment is required for breaker operations. However, offshore platforms have limited space and tight operational schedules. Interleaving breaker operations between or after profile control and displacement measures requires waiting for a suitable operational window, significantly reducing efficiency and increasing costs. Therefore, using solid breaker agents directly reduces the footprint and eliminates the need to wait for a dedicated operational window. Breaker powder needs to be processed into a solid, slow-release breaker to function after entering the near-wellbore area.

[0004] Currently, most sustained-release breaker agents are granular. For example, in Chinese patent application number CN201711466175, "A microcapsule breaker agent and its preparation method and application", acrylonitrile-butadiene-styrene copolymer is used as the wall material to coat the core material to obtain a microcapsule breaker agent with sustained-release effect. In Chinese patent application number 201810288627.X, "A preparation method of a water-based fracturing fluid breaker agent", modified sepiolite, microcrystalline cellulose, zinc polyacrylate resin and lard are used as coating materials to coat a mesoporous carrier to obtain a sustained-release breaker agent.

[0005] Since granular slow-release breaker is mostly used in fracturing operations, it is carried into the formation by high-viscosity fracturing fluid and releases its active ingredient to break the gel after the fracturing operation is completed. However, there are currently no dedicated solid slow-release breaker for profile control and flood control operations. Solid slow-release breaker cannot destroy the sealing of water channeling by gel plugging agents. It is only necessary to add it to break the gel in the near-wellbore area when over-sealing occurs. It cannot be injected along with gel plugging agents of a certain viscosity during profile control and flood control operations. Therefore, offshore profile control and flood control operations have placed new demands on the composition, shape, and application method of solid slow-release breaker. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a slow-release rubber-breaking rod for offshore decoy operations, as well as its preparation and application methods.

[0007] Specifically, the slow-release rubber-breaking rod for offshore decoy operations provided by this invention includes:

[0008] Debriding agent components, including oxidative debriding agents and buffers; and

[0009] A coating material is used to coat the outside of the degreasing agent component. The coating material is made by melt blending of various water-soluble resins.

[0010] The aforementioned slow-release breaker rod for offshore decoupling operations has a breaker component to coating material weight ratio of (1-1.5):(0.5-1).

[0011] In the aforementioned slow-release breaker rod for offshore decoy operations, the proportion of the breaker component, by mass percentage, is 85-90% for the oxidizing breaker and 10%-15% for the buffer.

[0012] The aforementioned slow-release breaker rod for offshore decoy operations includes one or more of the following oxidizing breaker agents: ammonium persulfate, sodium persulfate, benzoyl peroxide, hydrogen peroxide, and potassium permanganate.

[0013] The aforementioned slow-release rubber-breaking rod for offshore decoy operations includes one or more of the following buffers: citric acid, acetic acid, aminosulfonic acid, sodium hydroxide, and ammonium citrate.

[0014] The aforementioned slow-release rubber-breaking rods for offshore decoupling operations, by weight percentage, comprise 50%–80% polyvinyl alcohol resin, 15%–45% polyoxyethylene resin, and 5%–15% amide epoxy resin.

[0015] The aforementioned slow-release rubber-breaking rod for offshore decoy operations has a polyvinyl alcohol resin with a molecular weight of 20,000 to 100,000 g / mol and a degree of alcoholysis of 70 to 98%.

[0016] The aforementioned slow-release rubber-breaking rod for offshore decoy operations has a polyoxyethylene resin with a molecular weight of 7,000,000 to 10,000,000 g / mol and an amide epoxy resin with a molecular weight of 10,000 to 50,000 g / mol.

[0017] The present invention provides a method for preparing a slow-release colloid-breaking rod for offshore deflection operations, comprising:

[0018] (1) Compounding of coating materials

[0019] Each group of coating materials was dried at 80-90℃ for later use. Then, various water-soluble resins were melt-blended according to the formula and cooled to 50-75℃ for later use.

[0020] (2) Molding of slow-release rubber rods

[0021] Each component of the breaker is dried separately in a vacuum environment at 30-40°C for later use. The oxidized breaker and buffer are mixed according to the ratio, and the coating material after cooling in step (1) is added to obtain a mixture. The mixture is pressed using a rod mold, and after cooling, demolding and drying, a slow-release breaker rod for marine decoupling operations is obtained.

[0022] The preparation method of the above-mentioned slow-release colloid breaking rod for offshore decoupling operations, wherein the compounding of the coating material includes: adding polyvinyl alcohol resin to a heating pot, controlling the heating temperature to 90-150°C, and stirring until molten; then adding polyoxyethylene resin in 3-5 batches, stirring until molten; finally adding amide epoxy resin, heating and stirring; removing the material from the heating pot and cooling it to 50-75°C for later use.

[0023] In the above-mentioned method for preparing the slow-release colloid breaking rod for marine decoy operations, in step (2), the cooling time is 48 to 72 hours, and the drying includes ventilating and drying at 30 to 40°C for 12 to 24 hours.

[0024] The present invention provides a method for adding slow-release rubber-breaking rods for offshore deflection operations, comprising:

[0025] (1) A double valve dosing device is connected to the wellhead tree valve, and a chemical storage bin is set between the two valves;

[0026] (2) Close the lower valve, open the upper valve, and feed the slow-release rubber-breaking rod for marine decoy operations as described in any one of claims 1 to 8 into the silo;

[0027] (3) Close the upper valve and open the lower valve to let the rubber breaking rod fall into the oil pipe;

[0028] (4) Repeat the addition until the total addition amount reaches 0.5 to 1.5 tons, and control the total addition time to 4 to 8 hours;

[0029] (5) Inject water and flush for 3-4 hours to allow the de-gelling agent to enter the near-well zone and de-gel.

[0030] The above-mentioned method for adding slow-release rubber-breaking rods for offshore decoy operations allows the chemical silo to store 25-30 kg of rubber-breaking rods at a time.

[0031] The technical solution of the present invention has the following beneficial effects:

[0032] (1) The slow-release breaker rod for marine decoy operations of the present invention occupies a very small space compared to the liquid agent method, which solves the problems of large area and long waiting time for conventional breaker solution injection equipment; compared with granular slow-release breaker, the addition method is simpler and does not require carrying high viscosity polymer solution.

[0033] (2) The slow-release rubber breaking rod for marine decoy operations of the present invention uses industrial raw materials, and the molding and processing technology is simple and convenient for large-scale industrial production. Attached Figure Description

[0034] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention.

[0035] Figure 1 The slow-release gel-breaking rod processed in Example 1;

[0036] Figure 2 The diagram shows the state of the sustained-release gel-breaking stick after dissolution and the gel after mixing and breaking in Example 1. Detailed Implementation

[0037] To fully understand the purpose, features, and effects of this invention, the following detailed embodiments are provided. Except as described below, the process methods of this invention employ conventional methods or apparatus in the art. Unless otherwise specified, the terms and expressions used below have the meanings commonly understood by those skilled in the art.

[0038] When a range of values ​​is disclosed herein, the range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0039] A slow-release breaker rod for offshore decoy operations includes: a breaker component comprising an oxidizing breaker and a buffer; and a coating material coating the outside of the breaker component, wherein the coating material is a melt blend of various water-soluble resins.

[0040] The slow-release gel-breaking rod for offshore decoupling operations of the present invention uses water-soluble resin as the coating material to encapsulate the gel-breaking agent components. This design not only endows the gel-breaking rod with high strength, impact resistance, and flexural strength, making it more convenient to transport, but also ensures that the coating material completely dissolves in water after 3 to 4 hours, releasing the gel-breaking agent to effectively decompose the gel. Furthermore, the coating material leaves no residue after dissolving, thus avoiding the risk of additional blockage to pipelines and formations. Because it does not require carrying high-viscosity solutions or deploying specialized equipment when used on offshore platforms, its operation is extremely simple, thus possessing broad application prospects.

[0041] In some preferred embodiments, the weight ratio of the de-gumming component to the coating material is (1-1.5):(0.5-1).

[0042] In the slow-release breaker rod for marine decoy operations of the present invention, the effective content of the breaker component reaches 50% to 70%, which is high and results in good breaker performance. Practice has shown that when the proportion of the breaker component is too low, the breaker performance is poor; conversely, when the proportion of the breaker component is too high, the slow-release rod has insufficient strength and the release rate is too fast.

[0043] In some preferred embodiments, the oxidative breaker comprises 85-90% by mass percentage, and the buffer comprises 10-15%.

[0044] More preferably, the oxidative degreasing agent includes one or more of ammonium persulfate, sodium persulfate, benzoyl peroxide, hydrogen peroxide, and potassium permanganate; the buffer includes one or more of citric acid, acetic acid, aminosulfonic acid, sodium hydroxide, and ammonium citrate.

[0045] The coating material used in this invention is composed of water-soluble resins of different types and molecular weights. It can adjust the release time of the slow-release breaker rod according to the site conditions by adjusting the molecular weight, degree of hydrolysis and ratio of the water-soluble resin, so as to avoid damage to the oil pipeline caused by the excessive release rate of the breaker during construction.

[0046] In some preferred embodiments, the coating material comprises, by weight percentage, 50%–80% polyvinyl alcohol resin, 15%–45% polyoxyethylene resin, and 5%–15% amide epoxy resin.

[0047] More preferably, the polyvinyl alcohol resin has a molecular weight of 20,000 to 100,000 g / mol and a degree of alcoholysis of 70 to 98%; the polyoxyethylene resin has a molecular weight of 7,000,000 to 10,000,000 g / mol; and the amide epoxy resin has a molecular weight of 10,000 to 50,000 g / mol.

[0048] Among them, polyoxyethylene resin provides a rigid skeleton for the coating material to delay initial dissolution, polyvinyl alcohol resin is used to regulate the hydrophilicity of the coating material to achieve accelerated release in the middle stage, and amide epoxy resin has good wear resistance and impact resistance, playing a protective role during the transportation and addition of the debonding rod. The three water-soluble resins work synergistically to enable the coating material to completely dissolve in water in 3 to 4 hours. Moreover, it will not easily break or shatter during transportation and addition, and will not leave any residue after dissolution, thus avoiding the risk of additional blockage to the oil pipeline and formation.

[0049] On the other hand, the present invention also provides a method for preparing a slow-release colloid-breaking rod for offshore decoy operations, comprising:

[0050] (1) Compounding of coating materials

[0051] Each group of coating materials was dried at 80-90℃ for later use. Then, various water-soluble resins were melt-blended according to the formula and cooled to 50-75℃ for later use.

[0052] (2) Molding of slow-release rubber rods

[0053] Each component of the breaker is dried separately in a vacuum environment at 30-40°C for later use. The oxidized breaker and buffer are mixed according to the ratio, and the coating material after cooling in step (1) is added to obtain a mixture. The mixture is pressed using a rod mold, and after cooling, demolding and drying, a slow-release breaker rod for marine decoupling operations is obtained.

[0054] The preparation method of the slow-release breaker rod for marine decoupling operations of the present invention only requires fully mixing the coating material and the breaker component and then pouring it into a mold. The process is simple, the raw materials are widely available, and it is convenient for large-scale industrial production.

[0055] In some preferred embodiments, the compounding of the coating material includes: adding polyvinyl alcohol resin to a heating pot, controlling the heating temperature to 90-150°C, and stirring until it melts; then adding polyoxyethylene resin in 3-5 batches and stirring until it melts; finally adding amide epoxy resin, heating and stirring; and removing the material from the heating pot and cooling it to 50-75°C for later use.

[0056] By preparing the coating material according to the method of the present invention, the heating temperature can be reduced and the heating time shortened, so that the polyoxyethylene resin and amide epoxy resin can be uniformly dispersed in the polyvinyl alcohol resin, ensuring that the resulting broken bar has a uniform structure, high strength, and is resistant to bending, dropping and wear.

[0057] In some preferred embodiments, the molding of the slow-release breaker rod includes: drying the breaker components at 30–40°C using a low-temperature vacuum drying method; adding the breaker components to a kneader and mixing them evenly according to a weight ratio of coating material to breaker components of (0.5–1):(1–1.5), then adding the cooled coating material, kneading for 2–4 minutes, and pouring the mixture into a mold; preparing round rods with a diameter of 4–5 cm and a length of 50–60 cm using a rod-shaped pressing mold; demolding the round rods after cooling for 48–72 hours, and air-drying them at 30–40°C for 12–24 hours to obtain the final product.

[0058] This invention minimizes the decomposition of the desiccant components at high temperatures by pre-drying all components and controlling the temperature of the coating material at 50–75°C, and kneading it at this temperature. By cooling the mixture pressed in the mold for 48–72 hours, a dense skin layer can be formed. After demolding, the desiccant rod is air-dried at 30–40°C for 12–24 hours, which can eliminate the moisture adsorbed by the resin, uniformly dissipate heat to reduce local thermal shrinkage differences and prevent cracking of the slow-release rod, and effectively eliminate the microcrystalline areas in the coating material, so that there are no solid residues after dissolution.

[0059] Furthermore, the present invention also provides a method for adding slow-release rubber-breaking rods for offshore decoy operations, comprising:

[0060] (1) A double valve dosing device is connected to the wellhead tree valve, and a chemical storage bin is set between the two valves;

[0061] (2) Close the lower valve, open the upper valve, and put 25-30 kg of the slow-release rubber-breaking rods for marine decoy operations into the silo;

[0062] (3) Close the upper valve and open the lower valve to let the rubber breaking rod fall into the oil pipe;

[0063] (4) Repeat the addition until the total addition amount reaches 0.5 to 1.5 tons, and control the total addition time to 4 to 8 hours;

[0064] (5) Inject water and flush for 3-4 hours to allow the de-gelling agent to enter the near-well zone and de-gel.

[0065] The slow-release gel-breaking rod for offshore deflection operations of the present invention, used in conjunction with a small dual-valve dosing device, can be directly added downhole, simplifying the construction process; the designed dual-valve structure provides safety protection, preventing pressure rise during dosing and avoiding the overflow of highly oxidizing solutions that could cause harm to the device and construction personnel.

[0066] Example

[0067] The present invention is further illustrated below by way of embodiments, but the invention is not limited to the scope of the embodiments described herein. Experimental methods in the following embodiments, unless otherwise specified, were performed according to conventional methods and conditions. The raw materials used in the following embodiments were all commercially available.

[0068] Example 1:

[0069] (1) Compounding of coating materials:

[0070] Dry each group of coating materials separately at 80-90℃ for later use. Add 55 kg of polyvinyl alcohol resin (molecular weight 50000 g / mol, degree of hydrolysis 86%) to a heating pot, control the heating temperature at 100℃, and stir thoroughly until molten; then add 38 kg of polyoxyethylene resin (molecular weight 7000000 g / mol) in 4 batches, stirring thoroughly until molten; finally add 10 kg of amide epoxy resin (molecular weight 10000 g / mol), heat and stir until molten; remove the material from the heating pot and cool to 60℃ for later use.

[0071] (2) Forming of slow-release rubber-breaking rods:

[0072] Low-temperature vacuum drying was used to separately dry ammonium persulfate and ammonium citrate at 30–40°C for later use. An ammonium persulfate to ammonium citrate ratio of 1:1 was used as the breaking agent component. The coating material and breaking agent components were added sequentially to a kneader at a weight ratio of 1:1. After kneading for 3 minutes, the mixture was poured into a mold and a 5cm diameter, 60cm long rod was prepared using a rod-shaped pressing mold (see...). Figure 1 After cooling for 72 hours, the product is demolded and the round bar is air-dried at 35°C for 24 hours to obtain the final product.

[0073] Example 2:

[0074] Repeat the experimental steps of Example 1, except that in step (1), 75 kg of polyvinyl alcohol resin is added.

[0075] Example 3:

[0076] Repeat the experimental steps of Example 1, except that in step (2), the mass ratio of the coating component to the de-gelling agent component is 1:1.5.

[0077] Example 4:

[0078] Repeat the experimental steps of Example 1, except that the molecular weight of the polyoxyethylene resin in step (1) is 8,000,000 g / mol.

[0079] Example 5:

[0080] Repeat the experimental steps of Example 1, except that the molecular weight of polyvinyl alcohol resin in step (1) is 20000 g / mol.

[0081] Example 6:

[0082] Repeat the experimental steps of Example 1, except that the molecular weight of the amide epoxy resin in step (1) is 20000 g / mol.

[0083] Performance Evaluation

[0084] The performance of the sustained-release gel-breaking rods prepared in Examples 1-6 was tested according to the following method. The test results are shown in Tables 1 and 2. The test methods are as follows:

[0085] (1) Sustained release time

[0086] Static sustained-release performance: 10g of sustained-release breaker rods were placed in 300g of seawater, and the temperature was set at 65℃ for heat preservation. The solution was allowed to stand and dissolve for 8 hours. The solution was filtered to obtain the sustained-release breaker rod residue. The residue was dried under low temperature vacuum and weighed to calculate the sustained-release rate within 8 hours.

[0087] Formula for calculating sustained-release rate:

[0088] In the formula, C—the sustained-release rate of the sustained-release gel-breaking rod, %;

[0089] m1—Mass of residue from the slow-release colloid depressant, in grams;

[0090] m0 — Initial mass of the slow-release gel-breaking rod, in g.

[0091] (2) Dynamic sustained-release performance: 10g of sustained-release gelling rod was placed in 300g of seawater, the temperature was set to 65℃ for heat preservation, the stirring speed was set to 50r / min, and the dissolution time was recorded after the sustained-release gelling rod was observed to be completely dissolved.

[0092] (3) Debriding performance

[0093] Measure the viscosity of the gel after gelation, then mix the gel with the dissolved gel-breaking agent solution at a ratio of 1:1, store in an oven at 65°C for 4 hours, and measure the viscosity after gel breaking.

[0094] Table 1 Summary of sustained-release performance test results of sustained-release gel-breaking rods in Examples 1-6

[0095]

[0096] The results of the sustained-release performance test are shown in Table 1. Under static conditions, the sustained-release breaker rod has a sustained-release rate of 20-30% within 8 hours, which avoids damage to the oil pipe due to excessive dissolution during construction. Under dynamic conditions, the sustained-release breaker rod has a dissolution time of 3-5 hours, which ensures that the effective ingredients are released to break the bleach during water flushing, while also ensuring that subsequent production is not affected by clogging of the oil pipe.

[0097] Table 2. Degradation performance of slow-release breaker sticks

[0098]

[0099] The results of the glue-breaking performance test are shown in Table 2 and Figure 2 As shown, the slow-release breaker rod exhibits good breaker performance after dissolving.

[0100] The present invention has been disclosed above with reference to preferred embodiments. However, those skilled in the art should understand that these embodiments are merely illustrative of the invention and should not be construed as limiting its scope. It should be noted that any variations and substitutions equivalent to these embodiments should be considered to be covered within the scope of the claims. Therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A slow-release rubber-breaking rod for offshore decoy operations, characterized in that, include: Breaker components include oxidative breakers and buffers; and A coating material is used to coat the outside of the degreasing agent component. The coating material is composed of a melt blend of various water-soluble resins.

2. The slow-release rubber-breaking rod for offshore decoy operations according to claim 1, characterized in that, The weight ratio of the de-knock agent component to the coating material is (1-1.5):(0.5-1).

3. The slow-release rubber-breaking rod for offshore decoy operations according to claim 1, characterized in that, In the breaker components, the oxidative breaker accounts for 85-90% by mass percentage, and the buffer accounts for 10%-15%.

4. The slow-release rubber-breaking rod for offshore decoy operations according to claim 1, characterized in that, The oxidative degreasing agent includes one or more of ammonium persulfate, sodium persulfate, benzoyl peroxide, hydrogen peroxide, and potassium permanganate.

5. The slow-release rubber-breaking rod for offshore decoy operations according to claim 1, characterized in that, The buffer includes one or more of citric acid, acetic acid, sulfamic acid, sodium hydroxide, and ammonium citrate.

6. The slow-release rubber-breaking rod for offshore decoy operations according to claim 1, characterized in that, The coating material comprises, by weight percentage, 50%–80% polyvinyl alcohol resin, 15%–45% polyoxyethylene resin, and 5%–15% amide epoxy resin.

7. The slow-release rubber-breaking rod for offshore decoy operations according to claim 6, characterized in that, The polyvinyl alcohol resin has a molecular weight of 20,000 to 100,000 g / mol and a degree of alcoholysis of 70 to 98%.

8. The slow-release rubber-breaking rod for offshore decoy operations according to claim 6, characterized in that, The polyoxyethylene resin has a molecular weight of 7,000,000 to 10,000,000 g / mol; the amide epoxy resin has a molecular weight of 10,000 to 50,000 g / mol.

9. The method for preparing the slow-release rubber-breaking rod for offshore decoy operations according to any one of claims 1 to 8, characterized in that, include: (1) Compounding of coating materials Each group of coating materials was dried at 80-90℃ for later use. Then, various water-soluble resins were melt-blended according to the formula and cooled to 50-75℃ for later use. (2) Molding of slow-release rubber rods Each component of the breaker is dried separately in a vacuum environment at 30-40°C for later use. The oxidized breaker and buffer are mixed according to the ratio, and the coating material after cooling in step (1) is added to obtain a mixture. The mixture is pressed using a rod mold, and after cooling, demolding and drying, a slow-release breaker rod for marine decoupling operations is obtained.

10. The preparation method according to claim 9, characterized in that, The compounding of the coating material includes: adding polyvinyl alcohol resin to a heating pot, controlling the heating temperature to 90-150°C, and stirring until it melts; then adding polyoxyethylene resin in 3-5 batches and stirring until it melts; finally adding amide epoxy resin, heating and stirring; and removing the material from the heating pot and cooling it to 50-75°C for later use.

11. The preparation method according to claim 9, characterized in that, In step (2), the cooling time is 48 to 72 hours, and the drying includes ventilating and drying at 30 to 40°C for 12 to 24 hours.

12. A method for adding slow-release rubber-breaking rods for offshore decoy operations, characterized in that, include: (1) A double valve dosing device is connected to the wellhead tree valve, and a chemical storage bin is set between the two valves; (2) Close the lower valve, open the upper valve, and feed the slow-release rubber-breaking rod for marine decoy operations as described in any one of claims 1 to 8 into the silo; (3) Close the upper valve and open the lower valve to let the rubber breaker fall into the oil pipe; (4) Repeat the addition until the total addition amount reaches 0.5 to 1.5 tons, and control the total addition time to 4 to 8 hours; (5) Inject water and flush for 3-4 hours to allow the de-gelling agent to enter the near-well zone and de-gel.

13. The dosing method according to claim 12, characterized in that, The reagent silo can store 25-30 kg of breaker rods at a time.

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