Thermosetting resin gel composition for oil drilling and preparation method thereof

Abstract

The invention relates to the technical field of thermosetting resin preparation, in particular to a thermosetting resin gel composition for oil drilling and a preparation method thereof. The curing agent comprises the following raw materials in parts by mass: 15-60 parts of thermosetting resin, 1-3 parts of an external resin curing agent, 4-14 parts of an internal slow-release resin curing agent, 70-115 parts of metal oxide, 35-55 parts of phosphate, 1-5 parts of a fluid loss agent, 15-25 parts of a cooling retarder and 30-130 parts of water. According to the thermosetting resin gel composition for oil drilling and the preparation method of the thermosetting resin gel composition, provided by the invention, the solidification speed of the thermosetting resin gel composition can be delayed, an unsolidified state of 4-6 hours is reserved after the raw materials are mixed, and a mixed solution can be solidified again when being pumped to a corresponding position under a well, so that an excellent well cementation effect is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of thermosetting resin preparation, in particular to a thermosetting resin gel composition for oil drilling and a preparation method thereof. Background Art

[0002] In the field of oil drilling, cementing is to lower a certain size of casing string into the well, and inject cement slurry or resin composition around it to fix the casing on the well wall to prevent the well wall from collapsing. Its purpose is to: isolate loose, easy to collapse, easy to leak and other complex formations; isolate oil, gas, and water layers to prevent mutual leakage. In the current cementing technology, the high strength characteristics of thermosetting resin after curing are often used to form a section of resin tube at the expansion of the well wall underground, which plays the role of temporary casing. The thermosetting resin gel system used in this process needs to be mixed on the surface, and then pumped to the corresponding position underground through the drill pipe, and then start to cure after being pumped into the corresponding position. However, the existing thermosetting resin cures quickly, and generally thickens and solidifies about 1 hour after mixing, and it generally takes 4h to 6h for the drill pipe to pump the thermosetting resin gel system to the corresponding position underground. This results in the thermosetting resin solidifying before reaching the target position during the pumping process, affecting the final solidification effect.

[0003] Therefore, there is an urgent need for a resin composition that can slow down its solidification speed, which can retain a solidification time of 4 to 6 hours after mixing, so that the mixed liquid can solidify again when it is pumped to a corresponding position underground. Summary of the invention

[0004] The present invention provides a thermosetting resin gel composition for oil drilling, which overcomes the shortcomings of the above-mentioned prior art and can effectively solve the problem that the existing thermosetting resin composition for oil drilling has a fast curing speed, and the thermosetting resin begins to solidify before reaching the target position during the pumping process, which affects the final solidification effect.

[0005] One of the technical solutions of the present invention is achieved through the following measures: a thermosetting resin gel composition for oil drilling, wherein the raw materials, by mass, include 15 to 60 parts of thermosetting resin, 1 to 3 parts of external resin curing agent, 4 to 14 parts of internal slow-release resin curing agent, 70 to 115 parts of metal oxide, 35 to 55 parts of phosphate, 1 to 5 parts of fluid loss reducer, 15 to 25 parts of cooling retarder and 30 to 130 parts of water.

[0006] The following is a further optimization and / or improvement of one of the above-mentioned technical solutions: The above-mentioned thermosetting resin gel composition for oil drilling comprises, by mass, 38 parts of thermosetting resin, 2 parts of external resin curing agent, 10 parts of internal slow-release resin curing agent, 92 parts of metal oxide, 45 parts of phosphate, 3 parts of fluid loss reducer, 20 parts of cooling retarder and 80 parts of water.

[0007] The above-mentioned internal slow-release resin curing agent includes a resin curing agent and a hollow porous fiber. The resin curing agent in the internal slow-release resin curing agent is arranged in the hollow porous fiber and a layer of resin is cured on the outer layer of the hollow porous fiber. The resin curing agent is one or more of anhydrides, aliphatic amines, alicyclic amines, phenolic compounds and polyols.

[0008] The above-mentioned internal slow-release resin curing agent is prepared by the following method: S1, weighing the hollow porous fiber and the resin curing agent in a mass ratio of 1:8 to 10, mixing the two and stirring for 10 to 15 minutes; S2, placing the mixed and stirred hollow porous fiber and resin curing agent in an oven, evacuating the mixture at a pressure of 60 to 80 Hg column at room temperature for 50 to 70 minutes, taking the mixture out and letting it stand for 8 to 10 minutes, to obtain a hollow porous fiber containing a curing agent; S3, fully or intermittently coating the outer wall of the hollow porous fiber containing the curing agent with a polyurethane resin, and then placing it in an oven and heating it at 80° C. to 120° C. until the polyurethane resin is cured, thereby obtaining an internal slow-release resin curing agent.

[0009] The length of the hollow porous fiber is 0.5 cm to 2 cm.

[0010] The external resin curing agent is one or more of anhydrides, aliphatic amines, alicyclic amines, phenolic compounds and polyols.

[0011] The thermosetting resin is two or more selected from epoxy resin, phenolic epoxy resin, polybutylene resin, silicone resin and furan resin.

[0012] The metal oxide is one or more of dead-burned magnesium oxide, aluminum oxide, iron oxide, dicalcium oxide and metakaolin.

[0013] The phosphate is one or more of sodium monohydrogen phosphate, potassium dihydrogen phosphate, sodium dihydrogen phosphate, diammonium hydrogen phosphate, ammonium dihydrogen phosphate and polyphosphate.

[0014] The above-mentioned fluid loss additive is an AMPS multi-polymer fluid loss additive.

[0015] The above-mentioned cooling and retarding agent is one or more of magnesium nitrate, magnesium chloride and zeolite powder.

[0016] The above-mentioned thermosetting resin gel composition for oil drilling is prepared according to the following steps: The first step is to take the required amount of thermosetting resin, external resin curing agent, internal slow-release resin curing agent, metal oxide, phosphate, fluid loss reducer, cooling retarder and water, mix and stir; control the stirring speed to 200 rpm to 400 rpm, stir for 20 min to 40 min, and obtain a mixed solution; In the second step, a required amount of an internal slow-release resin curing agent is added to the mixed solution, and the mixture is stirred for 5 to 10 minutes to obtain a thermosetting resin gel composition for oil drilling.

[0017] The second technical solution of the present invention is achieved by the following measures: A method for preparing a thermosetting resin gel composition for oil drilling, comprising the following steps: The first step is to take the required amount of thermosetting resin, external resin curing agent, internal slow-release resin curing agent, metal oxide, phosphate, fluid loss reducer, cooling retarder and water, mix and stir; control the stirring speed to 200 rpm to 400 rpm, stir for 20 min to 40 min, and obtain a mixed solution; In the second step, a required amount of an internal slow-release resin curing agent is added to the mixed solution, and the mixture is stirred for 5 to 10 minutes to obtain a thermosetting resin gel composition for oil drilling.

[0018] The present invention provides a thermosetting resin gel composition for oil drilling and a preparation method thereof, which can slow down the solidification speed and keep the unsolidified state for 4 to 6 hours after the raw materials are mixed, so that the mixed liquid can be re-solidified at the corresponding position downhole after being pumped, thereby achieving an excellent cementing effect. DETAILED DESCRIPTION

[0019] The present invention is not limited by the following embodiments, and the specific implementation method can be determined according to the technical scheme of the present invention and the actual situation. Unless otherwise specified, the various chemical reagents and chemicals mentioned in the present invention are all known and commonly used chemical reagents and chemicals in the prior art; unless otherwise specified, the percentages in the present invention are all mass percentages; the normal temperature and room temperature in the present invention generally refer to the temperature of 15°C to 25°C, and are generally defined as 25°C.

[0020] The present invention will be further described below in conjunction with embodiments: Embodiment 1: The thermosetting resin gel composition for oil drilling comprises, by weight, 15 to 60 parts of thermosetting resin, 1 to 3 parts of external resin curing agent, 4 to 14 parts of internal slow-release resin curing agent, 70 to 115 parts of metal oxide, 35 to 55 parts of phosphate, 1 to 5 parts of fluid loss reducer, 15 to 25 parts of cooling retarder and 30 to 130 parts of water.

[0021] Example 2: As an optimization of the above example, a thermosetting resin gel composition for oil drilling comprises the following raw materials by mass: 38 parts of thermosetting resin, 2 parts of external resin curing agent, 10 parts of internal slow-release resin curing agent, 92 parts of metal oxide, 45 parts of phosphate, 3 parts of fluid loss reducer, 20 parts of cooling retarder and 80 parts of water.

[0022] Example 3: As an optimization of the above example, the internal slow-release resin curing agent includes a resin curing agent and a hollow porous fiber. The resin curing agent in the internal slow-release resin curing agent is arranged in the hollow porous fiber and a resin layer is cured on the outer layer of the hollow porous fiber. The resin curing agent is one or more of anhydrides, aliphatic amines, alicyclic amines, phenolic compounds and polyols.

[0023] Example 4: As an optimization of the above Example 4, the internal slow-release resin curing agent is prepared according to the following method: S1, weighing the hollow porous fiber and the resin curing agent in a mass ratio of 1:8 to 10, mixing the two and stirring for 10 to 15 minutes; S2, placing the mixed and stirred hollow porous fiber and resin curing agent in an oven, evacuating the mixture at a pressure of 60 to 80 Hg column at room temperature for 50 to 70 minutes, taking the mixture out and letting it stand for 8 to 10 minutes, to obtain a hollow porous fiber containing a curing agent; S3, fully or intermittently coating the outer wall of the hollow porous fiber containing the curing agent with a polyurethane resin, and then placing it in an oven and heating it at 80° C. to 120° C. until the polyurethane resin is cured, thereby obtaining an internal slow-release resin curing agent.

[0024] Example 5: As an optimization of the above examples 3 and 4, the length of the hollow porous fiber is 0.5 cm to 2 cm.

[0025] Embodiment 6: As an optimization of the above embodiment, the external resin curing agent is one or more of anhydrides, aliphatic amines, alicyclic amines, phenolic compounds and polyols.

[0026] Embodiment 7: As an optimization of the above embodiment, the thermosetting resin is two or more of epoxy resin, phenolic epoxy resin, polybutylene resin, silicone resin and furan resin.

[0027] Example 8: As an optimization of the above example, the metal oxide is one or more of dead-burned magnesium oxide, aluminum oxide, iron oxide, dicalcium oxide and metakaolin.

[0028] Example 9: As an optimization of the above example, the phosphate is one or more of sodium monohydrogen phosphate, potassium dihydrogen phosphate, sodium dihydrogen phosphate, diammonium hydrogen phosphate, ammonium dihydrogen phosphate and polyphosphate.

[0029] Embodiment 10: As an optimization of the above embodiment, the fluid loss additive is an AMPS multi-polymer fluid loss additive.

[0030] Example 11: As an optimization of the above example, the cooling and retarding agent is one or more of magnesium nitrate, magnesium chloride and zeolite powder.

[0031] Embodiment 12: A method for preparing a thermosetting resin gel composition for oil drilling, comprising the following steps: The first step is to take the required amount of thermosetting resin, external resin curing agent, internal slow-release resin curing agent, metal oxide, phosphate, fluid loss reducer, cooling retarder and water, mix and stir; control the stirring speed to 200 rpm to 400 rpm, stir for 20 min to 40 min, and obtain a mixed solution; In the second step, a required amount of an internal slow-release resin curing agent is added to the mixed solution, and the mixture is stirred for 5 to 10 minutes to obtain a thermosetting resin gel composition for oil drilling.

[0032] In the present invention, a small amount of resin curing agent is added as an external resin curing agent during the raw material mixing process, which is mainly used to maintain the fluidity of the system and has a small curing effect. In addition, most of the resin curing agent is made into an internal slow-release resin curing agent, and the hollow porous fiber is used as a slow-release space. After the hollow porous fiber and the resin curing agent are mixed, the air in the hollow space inside the hollow porous fiber is extracted by pressurizing and vacuumizing, and then the resin curing agent is introduced into the space inside the fiber. The hollow porous fiber is coated with a cured polyurethane resin layer on the outside. When the polyurethane resin is fully coated, during the pipeline transmission process of the entire thermosetting resin gel composition pumped into the target position downhole, the internal slow-release resin curing agent is squeezed to slowly release the resin curing agent; when the polyurethane resin is applied at intervals, a slow-release channel is formed between the externally cured polyurethane resins. During the pipeline transmission process of the entire thermosetting resin gel composition pumped into the target position downhole, the internal slow-release resin curing agent is squeezed to more smoothly release the resin curing agent from the slow-release channel, so that the solidification time of the entire system can be extended to 4 to 6 hours.

[0033] Example 13: The thermosetting resin gel composition for oil drilling comprises, by mass, 38 parts of thermosetting resin, 2 parts of external resin curing agent, 10 parts of internal slow-release resin curing agent, 92 parts of metal oxide, 45 parts of phosphate, 3 parts of fluid loss reducer, 20 parts of cooling retarder and 80 parts of water.

[0034] In this embodiment, the external resin curing agent is an acid anhydride, specifically phthalic anhydride; the resin curing agent used for the internal slow-release resin curing agent is also an acid anhydride, specifically phthalic anhydride.

[0035] The resin curing agent in the internal slow-release resin curing agent is arranged in the hollow porous fiber and a layer of resin is cured on the outer layer of the hollow porous fiber. The internal slow-release resin curing agent is prepared according to the following steps: S1, weighing the hollow porous fiber and the resin curing agent in a mass ratio of 1:9.63, mixing the two and stirring for 12 minutes; S2, placing the mixed and stirred hollow porous fiber and resin curing agent in an oven, evacuating the mixture at a pressure of 73 Hg for 60 min at room temperature, taking it out and letting it stand for 10 min; S3, coating the outer wall of the hollow porous fiber with polyurethane resin, and then placing it in an oven and baking it at 90° C. until the polyurethane resin is cured, thereby obtaining an internal slow-release resin curing agent, wherein the length of the hollow porous fiber is 0.5 cm to 2 cm.

[0036] In this embodiment, the thermosetting resin is an epoxy resin and a silicone resin mixed in a mass ratio of 1:2; the metal oxide is a mixture of dead-burned magnesium oxide and aluminum oxide in a mass ratio of 5:3; the phosphate is a mixture of sodium monohydrogen phosphate, potassium dihydrogen phosphate and sodium dihydrogen phosphate in a mass ratio of 1:1:1; the fluid loss additive is an AMPS multi-polymer fluid loss additive, specifically an SCF180 multi-polymer fluid loss additive; the cooling retarder is a mixture of magnesium nitrate, magnesium chloride and zeolite powder in a ratio of 3:2:5.

[0037] The preparation method of this embodiment comprises the following steps: The first step is to take the required amount of thermosetting resin, external resin curing agent, internal slow-release resin curing agent, metal oxide, phosphate, fluid loss reducer, cooling retarder and water, mix and stir; control the stirring speed to 300 rpm, stir for 35 minutes, and obtain a mixed solution; In the second step, a required amount of an internal slow-release resin curing agent is added to the mixed solution and stirred for 5 minutes to obtain a thermosetting resin gel composition for oil drilling.

[0038] Example 14: The thermosetting resin gel composition for oil drilling has the same raw material ratio as that of Example 13, except that in step S3 of the internal slow-release resin curing agent preparation process, the polyurethane resin is applied to the outer wall of the hollow porous fiber at intervals.

[0039] Example 15: The thermosetting resin gel composition for oil drilling comprises the following raw materials, by mass: 15 parts of thermosetting resin, 1 part of external resin curing agent, 6 parts of internal slow-release resin curing agent, 70 parts of metal oxide, 35 parts of phosphate, 1 part of fluid loss reducer, 15 parts of cooling retarder and 30 parts of water.

[0040] In this embodiment, the external resin curing agent is a mixture of anhydride and aliphatic amine in a mass ratio of 1:1, the specific anhydride is tung oil anhydride, and the aliphatic amine is triethylenetetramine; the resin curing agent used in the internal slow-release resin curing agent is anhydride, aliphatic amine, and alicyclic amine in a mass ratio of 2:1:1, the specific anhydride is tung oil anhydride, the aliphatic amine is triethylenetetramine, and the alicyclic amine is 2215 alicyclic amine modified curing agent. The resin curing agent in the internal slow-release resin curing agent is arranged in the hollow porous fiber and the outer layer of the hollow porous fiber is cured with a layer of resin layer; the internal slow-release resin curing agent is prepared according to the following steps: S1, weighing the hollow porous fiber and the resin curing agent in a mass ratio of 1:8, mixing the two and stirring for 10 minutes; S2, placing the mixed and stirred hollow porous fiber and resin curing agent in an oven, evacuating the mixture at a pressure of 65 Hg for 50 min at room temperature, taking it out and letting it stand for 8 min; S3, coating the outer wall of the hollow porous fiber with polyurethane resin, and then placing it in an oven and baking it at 85° C. until the polyurethane resin is cured, thereby obtaining an internal slow-release resin curing agent, wherein the length of the hollow porous fiber is 0.5 cm to 2 cm.

[0041] In this embodiment, the thermosetting resin is epoxy resin and phenolic epoxy resin mixed in a ratio of 3:1; the metal oxide is dead-burned magnesium oxide, aluminum oxide, and iron oxide mixed in a ratio of 1:1:1; the phosphate is sodium dihydrogen phosphate and polyphosphate mixed in a ratio of 1:1; the fluid loss additive is an AMPS multi-polymer fluid loss additive, specifically M-89L salt-resistant fluid loss additive; the cooling retarder is magnesium nitrate and magnesium chloride mixed in a ratio of 3:1.

[0042] In this embodiment, the thermosetting resin gel composition for oil drilling is prepared according to the following steps: The first step is to take the required amount of thermosetting resin, external resin curing agent, internal slow-release resin curing agent, metal oxide, phosphate, fluid loss reducer, cooling retarder and water, mix and stir; control the stirring speed to 200 rpm, stir for 20 minutes, and obtain a mixed solution; In the second step, a required amount of an internal slow-release resin curing agent is added to the mixed solution and stirred for 5 minutes to obtain a thermosetting resin gel composition for oil drilling.

[0043] Example 15: The thermosetting resin gel composition for oil drilling comprises, by weight, 60 parts of thermosetting resin, 3 parts of external resin curing agent, 14 parts of internal slow-release resin curing agent, 115 parts of metal oxide, 55 parts of phosphate, 5 parts of fluid loss reducer, 25 parts of cooling retarder and 130 parts of water; In this embodiment, the external resin curing agent is compounded from anhydride, phenolic compound and polyol in a mass ratio of 3:0.3:0.5, the specific anhydride is hexahydrophthalic anhydride, the phenolic compound is aralkylphenol, and the polyol is trimethylpentanediol; the resin curing agent used in the internal slow-release resin curing agent is compounded from anhydride, phenolic compound and polyol in a mass ratio of 3:0.3:0.5, the specific anhydride is hexahydrophthalic anhydride, the phenolic compound is aralkylphenol, and the selected polyol is trimethylpentanediol. The resin curing agent in the internal slow-release resin curing agent is arranged in the hollow porous fiber and the outer layer of the hollow porous fiber is cured with a layer of resin layer, and the internal slow-release resin curing agent is prepared according to the following steps: S1, weighing the hollow porous fiber and the resin curing agent in a mass ratio of 1:10, mixing the two and stirring for 10 to 15 minutes; S2, placing the mixed and stirred hollow porous fiber and resin curing agent in an oven, evacuating the mixture at a pressure of 80 Hg for 70 min at room temperature, taking it out and letting it stand for 10 min; S3, coating the outer wall of the hollow porous fiber with polyurethane resin, and then placing it in an oven and baking it at 115° C. until the polyurethane resin is cured, thereby obtaining an internal slow-release resin curing agent, wherein the length of the hollow porous fiber is 0.5 cm to 2 cm.

[0044] In this embodiment, the thermosetting resin is epoxy resin, polybutylene resin, and silicone resin compounded in a mass ratio of 1:1:1; the metal oxide is aluminum oxide, dicalcium oxide, and metakaolin compounded in a mass ratio of 3:1:2; the phosphate is sodium monohydrogen phosphate and polyphosphate compounded in a mass ratio of 5:1; the fluid loss additive is an AMPS multi-polymer fluid loss additive, specifically an SCF180 multi-polymer fluid loss additive; the cooling retarder is magnesium nitrate, magnesium chloride, and zeolite powder compounded in a mass ratio of 1:1:1.

[0045] In this embodiment, the thermosetting resin gel composition for oil drilling is prepared according to the following steps: The first step is to take the required amount of thermosetting resin, external resin curing agent, internal slow-release resin curing agent, metal oxide, phosphate, fluid loss reducer, cooling retarder and water, mix and stir; control the stirring speed to 400 rpm, stir for 40 minutes, and obtain a mixed solution; In the second step, a required amount of an internal slow-release resin curing agent is added to the mixed solution and stirred for 10 minutes to obtain a thermosetting resin gel composition for oil drilling.

[0046] Comparative Example 1: The raw material composition is the same as that of Example 13, except that the thermosetting resin gel composition is prepared according to the following steps: taking the required amount of thermosetting resin, external resin curing agent, internal slow-release resin curing agent, metal oxide, phosphate, fluid loss reducer, cooling retarder and water; placing all the weighed raw materials in a stirring device, controlling the stirring speed to 200 rpm, and stirring for 25 minutes. That is, the internal slow-release resin curing agent is mixed and stirred with other raw materials.

[0047] Comparative Example 2: The raw materials of the thermosetting resin gel composition include, by weight, 38 parts of thermosetting resin, 12 parts of resin curing agent, 92 parts of metal oxide, 45 parts of phosphate, 3 parts of fluid loss agent, 20 parts of cooling and retarding agent, and 80 parts of water. Among them, the resin curing agent is an acid anhydride, specifically phthalic anhydride; the selection of thermosetting resin, metal oxide, phosphate, fluid loss agent and cooling and retarding agent in Comparative Example 2 is the same as that in Example 13. That is, the resin curing in Comparative Example 2 is not prepared in advance as an internal slow-release resin curing agent, and is not carried out in a slow-release manner.

[0048] The performance of the thermosetting resin gel compositions for oil drilling prepared in Examples 13 to 16 and the thermosetting resin gel compositions prepared in Comparative Examples 1 to 2 was tested, and the test results are shown in Table 1. As can be seen from Table 1, the thermosetting resin gel compositions of Examples 13 to 16 can achieve a slow-setting effect, especially Example 13. Since the outer wall of the hollow porous fiber of Example 13 is fully coated with polyurethane resin and cured and dried, it mainly relies on extrusion to form a slow-release hole for the resin curing agent during transportation, so the release of the resin curing agent is the slowest, and it starts to solidify 352 minutes after mixing; the time when Comparative Examples 1 and Comparative Examples 2 start to thicken is obviously earlier. In Comparative Example 1, due to the premature mixing of the internal slow-release resin curing agent during the preparation process, extrusion will occur during the stirring process, resulting in the early release of a part of the resin curing agent under the action of stirring. Despite this, it can still maintain a good slow-setting effect in the end; in Comparative Document 2, due to the absence of an internal slow-release resin curing agent, its resin curing agent starts to solidify early, which is difficult to meet the construction requirements. Secondly, the curing completion time at 80°C is later for Examples 13 to 16 than for Comparative Examples 1 and 2, especially Comparative Example 2. In addition, since the internal slow-release resin curing agent contains hollow porous fibers, the compressive strength of the thermosetting resin gel composition for oil drilling is increased.

[0049] In summary, the present invention provides a thermosetting resin gel composition for oil drilling and a preparation method thereof, which can slow down its solidification speed and can remain in an unsolidified state for 4 to 6 hours after the raw materials are mixed, so that the mixed liquid can be re-solidified when it is pumped to the corresponding position underground, and the compressive strength of the resin composition solidified body is improved, thereby achieving an excellent cementing effect.

[0050] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effect. Non-essential technical features can be added or reduced according to actual needs to meet the requirements of different situations.

Claims

1. A thermosetting resin gel composition for oil drilling, characterized in that The raw materials include, by mass, 15 to 60 parts of thermosetting resin, 1 to 3 parts of external resin curing agent, 4 to 14 parts of internal slow-release resin curing agent, 70 to 115 parts of metal oxide, 35 to 55 parts of phosphate, 1 to 5 parts of fluid loss reducer, 15 to 25 parts of cooling retarder and 30 to 130 parts of water.

2. The thermosetting resin gel composition for oil drilling according to claim 1, characterized in that The raw materials include, by mass, 38 parts of thermosetting resin, 2 parts of external resin curing agent, 10 parts of internal slow-release resin curing agent, 92 parts of metal oxide, 45 parts of phosphate, 3 parts of fluid loss reducer, 20 parts of cooling retarder and 80 parts of water.

3. The thermosetting resin gel composition for oil drilling according to claim 1 or 2, characterized in that The internal slow-release resin curing agent includes a resin curing agent and a hollow porous fiber. The resin curing agent in the internal slow-release resin curing agent is arranged in the hollow porous fiber and a layer of resin is cured on the outer layer of the hollow porous fiber. The resin curing agent is one or more of anhydrides, aliphatic amines, alicyclic amines, phenolic compounds and polyols.

4. The thermosetting resin gel composition for oil drilling according to claim 3, characterized in that The internal slow-release resin curing agent is prepared by the following method: S1, weighing the hollow porous fiber and the resin curing agent in a mass ratio of 1:8 to 10, mixing the two and stirring for 10 to 15 minutes; S2, placing the mixed and stirred hollow porous fiber and resin curing agent in an oven, evacuating the mixture at a pressure of 60 to 80 Hg column at room temperature for 50 to 70 minutes, taking the mixture out and letting it stand for 8 to 10 minutes, to obtain a hollow porous fiber containing a curing agent; S3, fully or intermittently coating the outer wall of the hollow porous fiber containing the curing agent with a polyurethane resin, and then placing it in an oven and heating it at 80° C. to 120° C. until the polyurethane resin is cured, thereby obtaining an internal slow-release resin curing agent.

5. The thermosetting resin gel composition for oil drilling according to claim 3 or 4, characterized in that The length of the hollow porous fibers ranged from 0.5 cm to 2 cm.

6. The thermosetting resin gel composition for oil drilling according to any one of claims 1 to 5, characterized in that The external resin curing agent is one or more of anhydrides, aliphatic amines, alicyclic amines, phenolic compounds and polyols; or / and, the thermosetting resin is two or more of epoxy resins, phenolic epoxy resins, polybutylene resins, silicone resins and furan resins.

7. The thermosetting resin gel composition for oil drilling according to any one of claims 1 to 6, characterized in that The metal oxide is one or more of dead-burned magnesium oxide, aluminum oxide, iron oxide, dicalcium oxide and metakaolin; or / and the phosphate is one or more of sodium monohydrogen phosphate, potassium dihydrogen phosphate, sodium dihydrogen phosphate, diammonium hydrogen phosphate, ammonium dihydrogen phosphate and polyphosphate.

8. The thermosetting resin gel composition for oil drilling according to any one of claims 1 to 7, characterized in that The fluid loss reducer is an AMPS multi-polymer fluid loss reducer; or / and the cooling and retarding agent is one or more of magnesium nitrate, magnesium chloride and zeolite powder.

9. The thermosetting resin gel composition for oil drilling according to any one of claims 1 to 8, characterized in that Prepared according to the following steps: The first step is to take the required amount of thermosetting resin, external resin curing agent, internal slow-release resin curing agent, metal oxide, phosphate, fluid loss reducer, cooling retarder and water, mix and stir; control the stirring speed to 200 rpm to 400 rpm, stir for 20 min to 40 min, and obtain a mixed solution; In the second step, a required amount of an internal slow-release resin curing agent is added to the mixed solution, and the mixture is stirred for 5 to 10 minutes to obtain a thermosetting resin gel composition for oil drilling.

10. A method for preparing a thermosetting resin gel composition for oil drilling according to any one of claims 1 to 8, characterized in that The following steps are involved: The first step is to take the required amount of thermosetting resin, external resin curing agent, internal slow-release resin curing agent, metal oxide, phosphate, fluid loss reducer, cooling retarder and water, mix and stir; control the stirring speed to 200 rpm to 400 rpm, stir for 20 min to 40 min, and obtain a mixed solution; In the second step, a required amount of an internal slow-release resin curing agent is added to the mixed solution, and the mixture is stirred for 5 to 10 minutes to obtain a thermosetting resin gel composition for oil drilling.

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