Functional temporary plugging material, preparation method and application thereof

Abstract

The application provides a functional temporary plugging material and a preparation method and application thereof. The functional temporary plugging material comprises a degradable matrix and fluorescent tracers as tracer parts; wherein, when the degradable matrix is 100 parts by weight, the amount of the fluorescent tracers is 0.05-5 parts by weight, preferably 0.1-1 parts by weight; preferably, the fluorescent tracers are at least 3 kinds. The degradation degree of the temporary plugging material can be understood by detecting the concentration of the fluorescent tracers in the formation water brought to the ground, the application can effectively eliminate interference factors, obtain a detection result with higher reliability and anti-interference ability, and can assist oilfield fracturing construction.

Description

Technical Field

[0001] This invention relates to the field of oil and gas extraction, and more specifically, to a functional temporary plugging material, its preparation method, and its application. Background Technology

[0002] In oil and natural gas production, formation stimulation plays a crucial role, with fracturing being the primary method. By injecting high-pressure fluids, fractures are created in the formation, providing highly permeable channels for oil and gas production and increasing yields. This is one of the most commonly used processes in modern oil and gas extraction.

[0003] In fracturing operations, different types of temporary plugging materials are required due to varying process requirements. For example, when plugging the blast holes of the priority opening cluster, spherical blast hole plugging balls are needed to seal the blast holes; when plugging formation fractures, granular temporary plugging agents are needed to seal the formation fractures; and when separating different fracturing sections, bridge plugs, ball seals, etc., made of temporary plugging materials are needed to separate different fracturing sections.

[0004] After construction is completed, the temporary plugging material needs to degrade rapidly and fully into small molecules under reservoir conditions to avoid affecting subsequent construction and production. Therefore, various polyester materials with good degradation performance meet the practical requirements. For example, polyglycolic acid and polylactide are used as temporary plugging materials in oil and gas development due to their good mechanical properties and degradation characteristics.

[0005] However, in actual production, since the target location is in a well or crack several thousand meters deep, it is difficult to directly observe the actual degradation of the temporary plugging material, and it is impossible to know in time whether the degradation is sufficient, which makes the subsequent construction somewhat blind. Therefore, direct and rapid detection of the degradation of the material on the ground has important guiding value for construction. Summary of the Invention

[0006] To address the technical problems existing in the prior art, this invention provides a functional temporary plugging material, its preparation method, and its application.

[0007] This invention prepares a degradation material that can release a water-soluble tracer during the degradation process. During the degradation process underground, the released tracer can be carried out and detected by the produced water, thereby indicating the degradation status of the underground degradation material and assisting in oilfield fracturing operations.

[0008] One of the technical problems this invention aims to solve is the inability to detect the degradation of existing temporary plugging materials in practical applications. Because fracturing fluids used in practice have complex compositions, containing a large number of organic components including thickeners, drag reducers, flow aids, and anti-swelling agents, the degradation products of biodegradable materials are generally hydrocarbon compounds. Direct detection of these degradation products is difficult and subject to many influences, making it impossible to obtain effective results. Therefore, this invention introduces a fluorescent tracer into the temporary plugging material, dispersing it at the molecular level within the biodegradable material. As the biodegradable material degrades, the fluorescent tracer is released and carried to the surface by the produced water. The concentration of the tracer can then be determined by fluorescence detection, and the concentration curve can indicate the degree of degradation of the temporary plugging material.

[0009] The second technical problem this invention aims to solve is to endow the tracer with the ability to be carried to the surface along with the formation water production. By selecting a water-soluble fluorescent tracer, after the temporary plugging material degrades, the water-soluble fluorescent substance can dissolve in the formation water and be carried to the surface along with the formation water production.

[0010] The third technical problem this invention aims to solve is addressing the high cost, complex detection methods, and difficult processes of traditional oilfield tracers. Traditional tracers commonly use rare earth and isotope-based detection methods, which are costly and challenging. Therefore, this invention employs simple, convenient, and low-cost fluorescent tracers, effectively simplifying the detection process.

[0011] The fourth technical problem to be solved by this invention is to solve the dispersion problem of water-soluble fluorescent tracers in polyester biodegradable matrices. By mixing dispersants, compatibilizers and biodegradable matrices at the molecular level in a solvent, uniform dispersion of water-soluble fluorescent tracers in biodegradable matrices is achieved, reducing the influence of tracers on the mechanical properties of the matrix.

[0012] The fifth technical problem this invention aims to solve is addressing the impact of various impurities in produced water on detection results. Produced water often contains various fluorescently active substances, such as small amounts of crude oil, which affect fluorescence detection results. If the additive contains only one fluorescent substance, it is impossible to determine whether it is affected by impurities in the produced water, and the authenticity of the detection results cannot be determined. To solve this problem, this invention sets up a combination of three fluorescent substances with emission wavelength intervals greater than 40 nm for tracer detection. The ratio of the three fluorescent substances uses a known, predetermined value. When the detection results in the produced fluid are affected by impurities, it is highly unlikely that all detection results will be affected simultaneously. Therefore, by comparing the detection results of the three fluorescent substances and selecting the two with the detection result ratios closest to the known predetermined ratios as the calculation basis, the reliability and anti-interference ability of the detection results will be greatly enhanced.

[0013] One objective of this invention is to provide a functional temporary plugging material, comprising a biodegradable matrix and a fluorescent tracer as a tracer component; wherein, when the amount of biodegradable matrix is ​​100 parts by weight, the amount of fluorescent tracer is 0.05 to 5 parts by weight, preferably 0.1 to 1 parts by weight; preferably, the fluorescent tracer comprises at least three types.

[0014] In a preferred embodiment of the present invention,

[0015] Functional temporary plugging materials also include at least one of dispersants and compatibilizers; preferably,

[0016] When the amount of the biodegradable matrix is ​​100 parts by weight

[0017] The amount of the dispersant is 0.02 to 1 part by weight, more preferably 0.1 to 0.5 parts by weight;

[0018] The amount of the compatibilizer is 0.02 to 1 part by weight, more preferably 0.1 to 0.5 parts by weight.

[0019] In a preferred embodiment of the present invention,

[0020] The biodegradable matrix is ​​at least one of polyglycolic acid, polylactide, polybutylene succinate, polycaprolactone, polybutylene terephthalate, polybutylene terephthalate, polybutylene adipate, polymethyl ethylene carbonate, and polyhydroxyalkanoates; the melt index of the biodegradable matrix is ​​preferably above 1 g / 10 min.

[0021] The fluorescent tracer is a water-soluble fluorescent tracer, preferably at least three of the following: fluorescein derivatives, rhodamine derivatives, pyrene derivatives, fluorescent proteins and their derivatives, umbelliferone derivatives, and propidine derivatives; more preferably at least three of the following: fluorescein isothiocyanate, rhodamine tetramethylisothiocyanate, phycoerythrin, polydinophytic chlorophyll protein, propidine iodide, 4-methylumbelliferone, sodium fluorescein, and sodium 1,3,6,8-pyrene tetrasulfonate; further preferably three to five; and most preferably three or four.

[0022] The detection excitation wavelength (λex) and emission wavelength (λem) of each fluorescent tracer are shown in Table 1.

[0023] Table 1 Detection parameters for each fluorescent reagent

[0024] Fluorescent reagents λex / nm λem / nm Fluorescein isothiocyanate 490 525 Rhodamine tetramethylisothiocyanate 550 620 Phycoerythrin 488 576 Polydinophyll chlorophyll protein 490 677 Propidium iodide 488 615 4-Methylamphenone 360 450 Sodium fluorescein 328 532 Sodium 1,3,6,8-pyrenetetrasulfonate 454 511

[0025] In a preferred embodiment of the present invention,

[0026] The emission wavelength difference between any two fluorescent tracers is greater than or equal to 40 nm.

[0027] The greater the interval between the emission wavelengths of the fluorescent tracer, the smaller the mutual influence, and the farther apart the two peaks are, the more reliable the data obtained.

[0028] In a preferred embodiment of the present invention,

[0029] When there are three fluorescent tracers, the mass ratio of the three fluorescent tracers is (1-3):(1-3):(1-3); such as 1:1:1, 1:1:2, 1:2:2, 1:2:3, 2:2:3, 2:3:3, etc.

[0030] When there are four fluorescent tracers, the mass ratio of the four fluorescent tracers is (1-4):(1-4):(1-4):(1-4); such as 1:2:3:4, 1:1:2:4, 1:2:3:3, etc.

[0031] When there are 5 fluorescent tracers, the mass ratio of the 5 fluorescent tracers is (1-5):(1-5):(1-5):(1-5):(1-5), such as 1:2:3:4:5, etc.;

[0032] The ratio at the time of addition is fixed. During detection, the peak selected for detection is determined based on the relationship between the measured ratio and the ratio at the time of addition.

[0033] In a preferred embodiment of the present invention,

[0034] The dispersant is at least one of ionic and nonionic emulsifiers with an HLB value greater than 10. The dispersant is preferably at least one of sodium decaalkyl sulfate, sodium decaalkylbenzene sulfonate, sodium decaalkyl sulfonate, sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, sodium dodecyl sulfonate, sodium hexadecyl sulfate, sodium hexadecylbenzene sulfonate, and sodium hexadecyl sulfonate.

[0035] The compatibilizer is at least one of the following: copolymers containing maleic acid or its anhydride or amide, epoxy compounds, silane compatibilizers, titanate compatibilizers, aluminate compatibilizers, zirconate compatibilizers, borate compatibilizers, and aluminum-titanium composite compatibilizers, such as decamethylcyclopentanesiloxane, maleic anhydride-grafted POE compatibilizer, PTW-GMA grafting agent, etc.

[0036] The second objective of this invention is to provide a method for preparing a functional temporary plugging material, comprising:

[0037] (1) Add the fluorescent tracer, optional dispersant, and optional compatibilizer to an organic solvent to dissolve, then add the biodegradable matrix, stir to dissolve and mix evenly, and remove the solvent to obtain a mixture;

[0038] (2) The mixture obtained in step (1) is melt-extruded to obtain a substrate of functional temporary plugging material;

[0039] (3) Optionally, the substrate obtained in step (2) is made into balls, particles or parts to obtain the functional temporary plugging material.

[0040] In a preferred embodiment of the present invention,

[0041] Step (1),

[0042] The organic solvent is hexafluoroisopropanol;

[0043] The mass ratio of the organic solvent to the biodegradable matrix is ​​(2-6):1, preferably (3-5):1;

[0044] The dissolution temperature is room temperature to 50℃;

[0045] Different tracers dissolve at different rates; as long as they dissolve evenly, the mixing time is usually 0.5 to 2 hours.

[0046] One method to remove the solvent is by heating and evacuating the vacuum.

[0047] Step (2),

[0048] The melt extrusion is carried out in a screw extruder;

[0049] The extrusion temperature is 150–250℃, preferably 175–240℃;

[0050] The extruder speed is 100-500 rpm, preferably 150-400 rpm.

[0051] In a preferred embodiment of the present invention,

[0052] Step (3),

[0053] The obtained substrate can be processed into the corresponding shape according to the shape requirements of the temporary plugging material.

[0054] The ball is a temporary plugging ball with a diameter of less than 25mm, obtained by injection molding;

[0055] The particles are obtained through granulation and crushing.

[0056] The part is obtained by extruding bar stock and then machining it.

[0057] The third objective of this invention is to provide an application of a functional temporary plugging material in the field of oil and gas extraction, preferably in fracturing operations.

[0058] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0059] This invention prepares a temporary plugging material that can release a water-soluble tracer during degradation. It can be processed into different forms according to construction needs. The temporary plugging material degrades slowly in the formation environment. The soluble fluorescent substance is released into the formation water as the matrix degrades. It is carried to the surface for detection as the formation water is produced. The concentration of the tracer is obtained by fluorescence detection. The concentration curve can indicate the degree of degradation of the temporary plugging material, which can assist in oilfield fracturing construction.

[0060] The fluorescent substances in the temporary plugging material prepared by this invention are dispersed at the molecular level in the matrix. Therefore, the release of the fluorescent substances and the degradation of the matrix are completely synchronous. At the same time, the uniform dispersion of the fluorescent tracer in the degradable matrix reduces the influence of the tracer on the mechanical properties of the matrix. The fluorescent tracers are all water-soluble and can be dissolved in formation water, and are carried out to the surface with the production of formation water.

[0061] The concentration of fluorescent substances released after the degradation of the temporary plugging material obtained by the technical solution of this invention is uniquely encoded through a set ratio. When the produced fluid is contaminated with fluorescent impurities, the more reliable signal can be selected as the basis by comparing the ratios of different fluorescent substances with the set ratio, thus providing greater credibility and anti-interference capability. Produced water often contains various fluorescent active substances, such as small amounts of crude oil, which affect the fluorescence detection results. If the additive contains only one fluorescent substance, it is impossible to determine whether it is affected by impurities in the produced water, and the authenticity of the detection results cannot be determined. In this invention, a combination of three fluorescent substances with emission wavelength intervals greater than 40 nm is used for tracer detection. The ratio of the three fluorescent substances uses known, predetermined values. When the detection results in the produced fluid are affected by impurities, it is highly unlikely that all detection results will be affected simultaneously. By comparing the detection results of the three fluorescent substances, the two with the detection result ratios closest to the known set ratio are selected as the calculation basis, which greatly enhances the credibility and anti-interference capability of the detection results.

[0062] Compared to ordinary temporary plugging materials, the temporary plugging material obtained by this invention can indicate the degradation status of the temporary plugging material in the formation according to different geological environments, while ordinary temporary plugging materials do not have this function.

[0063] Compared with traditional tracer methods that commonly use rare earth elements and isotopes for detection, this invention effectively simplifies the detection process, reduces costs, and makes detection more convenient. Attached Figure Description

[0064] Figure 1 The graph shows the change in 4-methylumbelliferone concentration in field-extracted water at 95°C for different aging times of the functional temporary plugging material obtained in Example 1.

[0065] Figure 2The graph shows the change in phycoerythrin concentration of the functional temporary plugging material obtained in Example 2 at 95°C in field-extracted water at different aging times.

[0066] Figure 3 The graph shows the changes in the concentration of sodium 1,3,6,8-pyrene tetrasulfonate in the field-extracted water at 95°C for different aging times of the functional temporary plugging material obtained in Example 3.

[0067] Figure 4 The graph shows the change in phycoerythrin concentration of the functional temporary plugging material obtained in Example 4 at 95°C in field-extracted water at different aging times.

[0068] Figure 5 The graph shows the changes in the concentration of sodium 1,3,6,8-pyrene tetrasulfonate in the field-extracted water at 95°C for different aging times of the functional temporary plugging material obtained in Example 5.

[0069] Figure 6 The graph shows the change in phycoerythrin concentration of the functional temporary plugging material obtained in Example 6 at 95°C in field-extracted water at different aging times.

[0070] Figure 7 The graph shows the change in 4-methylumbelliferone concentration in field-extracted water at 95°C for different aging times of the functional temporary plugging material obtained in Example 7.

[0071] Figure 8 The graph shows the change in fluorescein isothiocyanate concentration of the functional temporary plugging material obtained in Example 1 at 95°C in deionized water for different aging times.

[0072] Figure 9 The graph shows the change in sodium fluorescein concentration at different aging times in deionized water at 95°C for the functional temporary plugging material obtained in Comparative Example 3. Detailed Implementation

[0073] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are still within the scope of protection of the present invention.

[0074] The raw materials used in the examples and comparative examples were all commercially available.

[0075] Test method:

[0076] The material compressive strength test standard is based on GBT1041 and is conducted on the Shimadzu AGX-V universal testing machine in Japan.

[0077] The fluorescence intensity detection method followed the operating procedures of the Hitachi F-2500 / 4500 spectrophotometer, using the aging supernatant for testing. A standard curve of concentration-light intensity was first calculated for different fluorescent substances, followed by testing the light intensity of the fluorescent substances in the supernatant. The concentration data of the fluorescent substances were obtained by comparing the values ​​with the standard curve.

[0078] All parts used in the following examples and comparative examples refer to parts by weight.

[0079] Examples 1-7

[0080] The fluorescent tracer, dispersant, and compatibilizer were added to hexafluoroisopropanol and dissolved uniformly at room temperature. The biodegradable matrix was then added, stirred until dissolved, and then heated and vacuumed to remove the hexafluoroisopropanol, yielding a mixture. The specific names and amounts of the fluorescent tracer, dispersant, compatibilizer, hexafluoroisopropanol, and biodegradable matrix are shown in Appendix 2.

[0081] The mixture powder obtained above was melt-extruded in a screw extruder to obtain a biodegradable substrate. The extrusion temperature was 185–235°C; the extruder speed was 300 rpm; and the obtained substrate was formed into temporary plugging balls with a diameter of 15 mm.

[0082] Comparative Example 1

[0083] The difference from Example 1 is that there is only one fluorescent tracer, which is 0.3 parts of fluorescein isothiocyanate;

[0084] Apart from the differences mentioned above, all other conditions in Comparative Example 1 were the same as in Example 1, resulting in a temporary plugging material.

[0085] Comparative Example 2

[0086] The difference from Example 1 is that no fluorescent tracer was added;

[0087] Apart from the differences mentioned above, all other conditions in Comparative Example 2 were the same as in Example 1, resulting in a temporary plugging material.

[0088] Comparative Example 3

[0089] The difference from Example 1 is that no dispersant or compatibilizer was added, and only one fluorescent tracer was used, which was 0.3 parts by weight of sodium fluorescein.

[0090] Apart from the differences mentioned above, all other conditions in Comparative Example 3 were the same as in Example 1, resulting in a temporary plugging material.

[0091] Table 2 Formulations of Examples 1-7 and Comparative Examples 1-3

[0092]

[0093]

[0094] The dosages in Table 2 are all in parts by weight.

[0095] The prepared 15mm diameter temporary plugging balls were placed in 100ml of field-collected water and aged at 95℃. After different times, the supernatant was taken and fluorescence detection was performed. The concentration of the fluorescent tracer in the solution was obtained by back-calculation based on the standard curve of different fluorescent tracers.

[0096] The emission and excitation wavelengths of each fluorescent tracer are shown in Table 1. Each sample was detected at its respective detection wavelength based on the added fluorescent tracer, and the concentration was calculated by back-calculating from the standard curve. To verify the influence of impurities in the produced water on the detection, Example 1 and Comparative Example 1 used produced water from Ming 15 in Zhongyuan Oilfield; Example 2, Example 4, Comparative Example 2, and Example 6 used produced water from Bin 31 in Shengli Oilfield; Example 3, Example 5, and Comparative Example 3 used produced water from Zhao 24 in Henan Oilfield; and Example 7 used produced water from Chen 25 South in Shengli Oilfield.

[0097] Table 3 shows the mass ratio of fluorescent tracer detection after aging in water in Examples 1-7.

[0098]

[0099] Table 3 shows the addition of fluorescent tracer and its mass ratio, as well as the detection mass ratio of the fluorescent tracer. It can be seen that:

[0100] In Example 1, the mass ratio of 4-methylamphetamine, sodium fluorescein, and propidium iodide added was 3:2:1, while the detection mass ratio was 2.9:4.8:0.98. Among them, the wavelength of sodium fluorescein was most affected by impurities and could be eliminated. Using 4-methylamphetamine or propidium iodide as the basis for concentration judgment is more accurate.

[0101] Similarly, in Examples 2, 4, and 6, fluorescein isothiocyanate, which is most affected by impurities, can be removed, and using phycoerythrin or polydinophytic chlorophyll protein as the basis for judgment is more accurate.

[0102] In Examples 3 and 5, the mass ratio of the three fluorescent tracers was close to the mass ratio of the added tracers, proving that there were no interfering impurities in the extracted fluid.

[0103] In Example 7, the mass ratios of three fluorescent tracers were close to the added mass ratio. The two fluorescent tracers, sodium fluorescein and phycoerythrin, were interfered with. Therefore, it is more accurate to use the other three fluorescent tracers as the basis for judgment.

[0104] Figures 1-9The content of fluorescent tracer in the field-extracted water was measured as described above, depending on the aging time of the functional temporary plugging materials prepared in Examples 1-7 and Comparative Examples 1 and 3 (4-methylumbelliferone in Examples 1 and 7, phycoerythrin in Examples 2, 4 and 6, and sodium 1,3,6,8-pyrenetetrasulfonate in Examples 3 and 5).

[0105] As can be seen from the figure, in the samples of Examples 1-7, the concentration of the fluorescent tracer steadily increased and then stabilized with different aging times. Therefore, it can be used as an evaluation basis for the degradation of the temporary plugging material in actual construction. It can be seen that the temporary plugging material takes approximately more than 24 hours to completely degrade at 95°C.

[0106] In Comparative Example 1, only one fluorescent tracer, fluorescein isothiocyanate, was used. Because it was directly affected by impurities in the extracted fluid, the resulting concentration curve fluctuated significantly and could not effectively indicate the degradation of the material matrix. In Comparative Example 3, the fluorescent tracer sodium fluorescein was unaffected, resulting in relatively stable detection data. However, since there was no verification using different proportions of fluorescent tracer signals as described in this invention, the reliability of data from a single fluorescent tracer is a probabilistic issue. This also demonstrates the role of the different proportions of fluorescent tracer content in the reliability of the scheme in this invention.

[0107] Meanwhile, in the sample of Comparative Example 3, the concentration of fluorescent tracer in water increased with different aging times, but the rising curve was not stable due to the absence of dispersant and compatibilizer. Furthermore, the compressive strength test results in Table 4 show that the mechanical properties of the temporary plugging material were affected by the absence of dispersant and compatibilizer, with the compressive strength decreasing by more than 10%. This was mainly due to the uneven distribution of fluorescent tracer in the material.

[0108] Table 4. Compressive strength of the temporary plugging materials prepared in Example 1 and Comparative Example 3.

[0109] Compressive strength (MPa) Example 1 270 Comparative Example 3 240

[0110] Table 4 shows the compressive strength of the temporary plugging materials prepared in Example 1 and Comparative Example 3. In Example 1, a dispersant and a compatibilizer were added, and the fluorescent tracer was more uniformly dispersed in the biodegradable matrix, which had less impact on the mechanical properties of the material.

[0111] The functional temporary plugging materials prepared in Examples 1-7 have fluorescent tracers dispersed at the molecular level in the matrix, minimizing their impact on the matrix's mechanical properties. Soluble fluorescent substances are released into formation water as the matrix degrades, and are carried to the surface for detection as the formation water is produced. The concentration of the tracer is obtained through fluorescence detection, and the concentration curve indicates the degree of degradation of the temporary plugging material. By comparing the detection results of the three fluorescent substances, fluorescent tracers that are inaccurate due to impurities can be eliminated, greatly enhancing the reliability and anti-interference ability of the detection results. These materials can be used as temporary plugging materials in fracturing operations, providing a more efficient solution for formation stimulation and oil and gas field production enhancement.

Claims

1. A functional temporary plugging material, comprising a degradable matrix and a fluorescent tracer as a tracer part; wherein, The amount of degradable matrix is 100 parts by weight, and the amount of fluorescent tracer is 0.05-5 parts by weight; the fluorescent tracer is at least three of fluorescein isothiocyanate, tetramethyl rhodamine isothiocyanate, phycoerythrin, peridinin chlorophyll protein, propidium iodide, 4-methylumbelliferone, fluorescein sodium, 1,3,6,8-pyrene tetrasulfonic acid sodium salt; the emission wavelength difference between the fluorescent tracers is greater than or equal to 40 nm.

2. The functional type bridging material of claim 1, wherein: The amount of degradable matrix is 100 parts by weight, and the amount of fluorescent tracer is 0.1-1 parts by weight.

3. The functional temporary plugging material of claim 1, wherein: Further comprising at least one of a dispersing agent and a compatibilizer.

4. The functional temporary plugging material of claim 3, wherein: The amount of degradable matrix is 100 parts by weight, The amount of dispersing agent is 0.02-1 parts by weight; and / or, The amount of compatibilizer is 0.02-1 parts by weight.

5. The functional temporary plugging material of claim 4, wherein: The amount of degradable matrix is 100 parts by weight, The amount of dispersing agent is 0.1-0.5 parts by weight; and / or, The amount of compatibilizer is 0.1-0.5 parts by weight.

6. The functional temporary plugging material of claim 1, wherein: The degradable matrix is at least one of polyglycolide, polylactide, polybutylene succinate, polycaprolactone, polybutylene terephthalate-adipate, polybutylene terephthalate, polybutylene succinate-adipate, polymethyl ethylene carbonate, polyhydroxyalkanoate; and / or, The fluorescent tracer is 3-5 kinds.

7. The functional temporary plugging material of claim 1, wherein: When the fluorescent tracer is 3 kinds, the mass ratio of the 3 fluorescent tracers is (1-3):(1-3):(1-3); when the fluorescent tracer is 4 kinds, the mass ratio of the 4 fluorescent tracers is (1-4):(1-4):(1-4):(1-4); and when the fluorescent tracer is 5 kinds, the mass ratio of the 5 fluorescent tracers is (1-5):(1-5):(1-5):(1-5):(1-5).

8. The functional temporary plugging material of claim 3, wherein: The dispersing agent is at least one of an ionic or non-ionic emulsifier with an HLB value greater than 10; and / or, The compatibilizer is at least one of a copolymer containing maleic acid or its anhydride or its amide, an epoxy compound, a silane compatibilizer, a titanate compatibilizer, an aluminate compatibilizer, a zirconate compatibilizer, a borate compatibilizer, and an aluminum-titanium composite compatibilizer.

9. The functional temporary plugging material of claim 8, wherein: The dispersing agent is at least one of sodium decyl sulfate, sodium decylbenzenesulfonate, sodium dodecyl sulfate, sodium dodecylbenzenesulfonate, sodium dodecylsulfonate, sodium hexadecyl sulfate, sodium hexadecylbenzenesulfonate, and sodium hexadecylsulfonate.

10. A method for preparing the functional temporary plugging material of any one of claims 1-9, comprising: ​ ​ (1) adding a fluorescent tracer, optionally a dispersant, optionally a compatibilizer into an organic solvent to dissolve, then adding a degradable matrix to stir, dissolve and mix uniformly, and obtaining a mixture after removing the solvent; (2) obtaining a substrate of the functional temporary plugging material by melt extrusion of the mixture obtained in step (1); (3) optionally, forming the substrate obtained in step (2) into a ball, a particle or a piece to obtain the functional temporary plugging material.

11. The preparation method of the functional temporary plugging material according to claim 10, wherein: in step (1), the organic solvent is hexafluoroisopropanol; and / or, the mass ratio of the organic solvent to the degradable matrix is (2-6):1; and / or, the temperature for dissolving is room temperature-50℃; and / or, in step (2), the melt extrusion is performed in a screw extruder; the extrusion temperature is 150-250℃; and / or, the rotating speed of the extruder is 100-500 rpm.

12. The preparation method of the functional temporary plugging material according to claim 11, wherein: in step (1), the mass ratio of the organic solvent to the degradable matrix is (3-5):1; and / or, in step (2), the extrusion temperature is 175-240℃; and / or, the rotating speed of the extruder is 150-400 rpm.

13. The preparation method of the functional temporary plugging material according to claim 10, wherein: in step (3), the ball is a temporary plugging ball with a diameter less than 25 mm, which is obtained by injection molding; and / or, the particle is obtained by granulation or crushing; and / or, the piece is obtained by machining after extruding a rod.

14. Use of the functional temporary plugging material according to any one of claims 1-9 or obtained by the preparation method according to any one of claims 10-13 in the field of oil and gas exploitation.

15. Use of the functional temporary plugging material according to claim 14 in fracturing operation. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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