A petroleum fracturing proppant containing fly ash and its preparation method

Abstract

The present invention relates to the technical field of fracturing proppants, specifically to a petroleum fracturing proppant containing fly ash and a preparation method thereof: the proppant comprises the following raw materials: zircon sand, quartz sand, clay, sodium hexametaphosphate, powder, bauxite powder, and a binder. In the present invention, in the preparation of the petroleum fracturing proppant, the fly ash can be subjected to high temperature and alkali treatment to optimize its surface structure, dimethyl sulfoxide as a polar solvent can assist in the uniform dispersion of the various components, 3-aminopropylmethyldimethoxysilane can improve the interface bonding between the fly ash and other component materials, and enhance the adhesion between the granular materials, and diethylenetriamine pentaacetic acid and N-hydroxysuccinimide can synergistically chelate metal ions to form a tight three-dimensional network structure, thereby enhancing the stability of the various structural combinations in the petroleum fracturing proppant, thereby achieving the purpose of improving the strength performance of the petroleum fracturing proppant.

Description

Technical Field

[0001] The invention relates to the technical field of fracturing proppants, in particular to a petroleum fracturing proppant containing fly ash components and a preparation method thereof. Background Art

[0002] Petroleum fracturing proppant is a key material in fracturing operations for unconventional oil and gas extraction such as shale gas. It is carried into formation cracks through fracturing fluid. Its function is to support the cracks to remain open and ensure that oil and gas flow smoothly to the wellbore. It is crucial to increasing oil and gas production and development efficiency.

[0003] Existing proppants for oil fracturing are made by mixing and sintering multiple high-hardness materials. This can lead to defects in the bonding of the various components, which can affect the strength of the proppants. To address this issue, the present invention provides a fly ash-containing proppant for oil fracturing and a method for its preparation. Summary of the Invention

[0004] The purpose of the present invention is to provide a petroleum fracturing proppant containing fly ash components and a preparation method thereof. The petroleum fracturing proppant prepared by the present invention not only has good compressive strength performance, but also has excellent crushing rate performance, effectively improving the performance of the petroleum fracturing proppant.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] In a first aspect, the present invention provides a fly ash-containing petroleum fracturing proppant, comprising the following raw materials: zircon sand, quartz sand, clay, sodium hexametaphosphate, powder, bauxite powder, and a binder, wherein the weight percentages of the raw materials are: 8-10% quartz sand, 1-2% clay, 2-4% sodium hexametaphosphate, 12-16% powder, 1-2% bauxite powder, and 4-6% binder, with the balance being made up to 100% by zircon sand;

[0007] The preparation of the powder comprises the following steps:

[0008] S1: base material preparation, the raw material of the base material is fly ash;

[0009] S2: preparing a mixture, wherein the raw materials of the mixture include dimethyl sulfoxide, diethylenetriamine pentaacetic acid, 3-aminopropylmethyldimethoxysilane, methyl glycol chitosan, N-hydroxysuccinimide, polyvinyl pyrrolidone, and deionized water;

[0010] S3: Mixing treatment: the base material and the admixture are mixed to obtain a powder.

[0011] Furthermore, the method for preparing the base material is as follows: fly ash is subjected to magnetic separation and flotation treatment to remove impurities, and then screened. The particle size of the fly ash after screening is 200-300 μm. The screened fly ash is added to a muffle furnace for calcination. The calcination treatment is set at a heating rate of 10-20°C / min, the temperature is raised to 800-900°C, and the temperature is kept for 30-50 minutes. After the calcination treatment is completed, it is waited to cool to room temperature. The resulting product is added to a mixer, sodium hydroxide solution is added to the mixer, and the mixer is set to 400-600 r / min for stirring for 30-40 minutes. The resulting product is washed with deionized water, and then filtered and dried to obtain the base material.

[0012] Furthermore, the mass of the sodium hydroxide solution is 2 to 3 times the mass of the fly ash after screening, and the mass concentration of the sodium hydroxide solution is 4 to 6%.

[0013] Furthermore, the method for preparing the mixture is as follows: dimethyl sulfoxide is added to a water bath, the water bath is heated to 70-80°C, then diethylenetriamine pentaacetic acid is added, the water bath is connected to a magnetic stirrer, the magnetic stirrer is set to a speed of 80-120 r / min, and constant temperature stirring is carried out for 10-20 minutes, then the temperature is set to 100-120°C, 3-aminopropylmethyldimethoxysilane, methyl glycol chitosan, and N-hydroxysuccinimide are added, and the reaction is carried out at a constant temperature for 20-30 minutes. After cooling to 70-80°C, polyvinyl pyrrolidone is added, the temperature is set to 60-70°C, the magnetic stirrer speed is 100-200 r / min, and constant temperature stirring is carried out for 2-4 hours. The resulting product and deionized water are added to a mixer, and the mixer is set to 400-600 r / min and stirred for 20-30 minutes to prepare a mixture.

[0014] Furthermore, the mass ratio of the raw materials in the mixture is 100: (4-6): (6-8): (10-12): (2-4): (0.8-1.2): (200-220).

[0015] Furthermore, the mass ratio of the base material to the mixing agent is 1:(1.6-1.8).

[0016] Furthermore, the mixing method is as follows: the base material and the mixing agent are added to a mixer, the mixer is set to 400-600 r / min and stirred for 30-40 minutes to obtain a slurry, the slurry is pumped into a spray drying tower for spray granulation treatment, the spray drying tower is set to have an inlet temperature of 160-180°C, an outlet temperature of 80-90°C, an atomization pressure of 0.3-0.5 MPa, and a feed rate of 10-20 L / h to obtain a granular material, the granular material, nano-silica, and nano-zirconium oxide are added to the mixer, the mixer is set to 600-800 r / min and stirred for 40-50 minutes, the mixing treatment is completed, and a powder is obtained.

[0017] Furthermore, the particle sizes of nano-silicon dioxide and nano-zirconia are 10-30 nm, the mass of nano-silicon dioxide is 5-7% of the mass of the granular material, and the mass of nano-zirconia is 1-3% of the mass of the granular material.

[0018] Furthermore, the binder is silica sol.

[0019] In a second aspect, the present invention also provides a method for preparing a petroleum fracturing proppant containing fly ash components, comprising the following steps: weighing zircon sand, quartz sand, clay, sodium hexametaphosphate, powder, bauxite powder, and binder as needed and adding them to a mixer, setting the mixer to 600-800 r / min and stirring for 40-50 minutes to obtain a mixture, adding the mixture to a disc granulator for granulation, the granulated particle size is 150-200 μm, and sintering the obtained product, setting the heating rate to 5-10°C / min, heating to 300-500°C, and keeping warm for 20-30 minutes, then setting the heating rate to 10-20°C / min, heating to 1200-1300°C, and keeping warm for 20-30 minutes to obtain a petroleum fracturing proppant.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. In the present invention, in the preparation of petroleum fracturing proppant, fly ash can be treated with high temperature and alkali to optimize its surface structure. Dimethyl sulfoxide as a polar solvent can assist in the uniform dispersion of various components. 3-aminopropylmethyldimethoxysilane can improve the interface bonding between fly ash and other component materials and enhance the adhesion between particulate materials. Diethylenetriaminepentaacetic acid and N-hydroxysuccinimide can synergistically chelate metal ions to form a tight three-dimensional network structure, thereby enhancing the stability of various structural combinations in the petroleum fracturing proppant, thereby achieving the purpose of improving the strength performance of the petroleum fracturing proppant.

[0022] 2. In the present invention, the addition of nano-silica and nano-zirconia can fill the micropores in the oil fracturing proppant system. After filling the micropores, it can inhibit the coarsening of grains, thereby achieving the purpose of refining the grain size after sintering and improving the density of the material. Through the combined spray drying treatment of the base material and the mixture, uniform spherical particles are formed after spray drying. The spherical particles can evenly distribute stress during the use of the fracturing proppant, reduce the breakage caused by local stress concentration, and further improve the strength performance of the oil fracturing proppant. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The invention proposes a flow chart of a petroleum fracturing proppant containing fly ash and a preparation method thereof. DETAILED DESCRIPTION

[0024] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0025] It should be noted that the raw materials used in the following examples are all commercially available raw materials.

[0026] Example 1:

[0027] Raw material preparation: 8% quartz sand, 1% clay, 2% sodium hexametaphosphate, 12% powder, 1% bauxite powder, 4% binder, and the balance is supplemented to 100% by zircon sand;

[0028] The preparation of the powder comprises the following steps:

[0029] S1: base material preparation, the raw material of the base material is fly ash;

[0030] The base material preparation method is as follows: fly ash is subjected to magnetic separation and flotation treatment to remove impurities, and then screened. The particle size of the fly ash after screening is 200 μm. The screened fly ash is added to a muffle furnace for calcination. The calcination process is set to a heating rate of 10°C / min, and the temperature is raised to 800°C, and the temperature is kept for 30 minutes. After the calcination process is completed, the mixture is allowed to cool to room temperature. The resulting product is added to a mixer, and sodium hydroxide solution is added to the mixer. The mixer is set to 400 r / min and stirred for 30 minutes. The resulting product is washed with deionized water, and then filtered and dried to obtain the base material. The mass of the sodium hydroxide solution is twice the mass of the screened fly ash, and the mass concentration of the sodium hydroxide solution is 4%.

[0031] S2: preparation of a mixture, wherein the raw materials of the mixture include dimethyl sulfoxide, diethylenetriamine pentaacetic acid, 3-aminopropylmethyldimethoxysilane, methyl glycol chitosan, N-hydroxysuccinimide, polyvinyl pyrrolidone, and deionized water;

[0032] The preparation method of the mixture is as follows: dimethyl sulfoxide is added to a water bath, the water bath is heated to 70°C, then diethylenetriamine pentaacetic acid is added, the water bath is connected to a magnetic stirrer, the speed of the magnetic stirrer is set to 80r / min, and the mixture is stirred at a constant temperature for 10 minutes, then the temperature is set to 100°C, 3-aminopropylmethyldimethoxysilane, methyl glycol chitosan, and N-hydroxysuccinimide are added, and the mixture is reacted at a constant temperature for 20 minutes. After the temperature is cooled to 70°C, polyvinyl pyrrolidone is added, the temperature is set to 60°C, the speed of the magnetic stirrer is 100r / min, and the mixture is stirred at a constant temperature for 2 hours. The obtained product and deionized water are added to a mixer, and the mixer is set to 400r / min and stirred for 20 minutes to prepare a mixture, wherein the mass ratio of each raw material in the mixture is 100:4:6:10:2:0.8:200, and the mass ratio of the base material to the mixture is 1:1.6;

[0033] S3: Mixing process: mixing the base material and the admixture to obtain a powder;

[0034] The mixing method is as follows: the base material and the mixing agent are added to the mixer, the mixer is set to 400r / min and stirred for 30 minutes to obtain a slurry, the slurry is pumped into a spray drying tower for spray granulation treatment, the spray drying tower is set to an inlet temperature of 160°C, an outlet temperature of 80°C, an atomization pressure of 0.3MPa, and a feed rate of 10L / h to obtain a granular material, the granular material, nano-silicon dioxide, and nano-zirconium oxide are added to the mixer, the mixer is set to 600r / min and stirred for 40 minutes, the mixing treatment is completed, and a powder is obtained.

[0035] The particle sizes of nano-silicon dioxide and nano-zirconia are 10 nm, the mass of nano-silicon dioxide is 5% of the mass of the particle material, and the mass of nano-zirconia is 1% of the mass of the particle material.

[0036] The binder is silica sol.

[0037] Preparation of petroleum fracturing proppant: comprising the following steps: weighing zircon sand, quartz sand, clay, sodium hexametaphosphate, powder, bauxite powder, and binder as needed, adding them into a mixer, setting the mixer to 600 r / min and stirring for 40 minutes to prepare a mixture, adding the mixture into a disc granulator for granulation, the granulated particle size is 150 μm, and sintering the obtained product, setting the heating rate to 5°C / min, heating to 300°C, and keeping warm for 20 minutes, then setting the heating rate to 10°C / min, heating to 1200°C, and keeping warm for 20 minutes to prepare the petroleum fracturing proppant.

[0038] Example 2:

[0039] Raw material preparation: 9% quartz sand, 1.5% clay, 3% sodium hexametaphosphate, 14% powder, 1.5% bauxite powder, 5% binder, and the balance is supplemented by zircon sand to 100%;

[0040] The preparation of the powder comprises the following steps:

[0041] S1: base material preparation, the raw material of the base material is fly ash;

[0042] The base material preparation method is as follows: fly ash is subjected to magnetic separation and flotation treatment to remove impurities, and then screened. The particle size of the fly ash after screening is 250 μm. The screened fly ash is added to a muffle furnace for calcination. The calcination process is set to a heating rate of 15°C / min, and the temperature is raised to 850°C and kept warm for 40 minutes. After the calcination process is completed, the temperature is cooled to room temperature. The resulting product is added to a mixer, and sodium hydroxide solution is added to the mixer. The mixer is set to 500 r / min and stirred for 35 minutes. The resulting product is washed with deionized water, and then filtered and dried to obtain the base material. The mass of the sodium hydroxide solution is 2.5 times the mass of the screened fly ash, and the mass concentration of the sodium hydroxide solution is 5%.

[0043] S2: preparation of a mixture, wherein the raw materials of the mixture include dimethyl sulfoxide, diethylenetriamine pentaacetic acid, 3-aminopropylmethyldimethoxysilane, methyl glycol chitosan, N-hydroxysuccinimide, polyvinyl pyrrolidone, and deionized water;

[0044] The preparation method of the mixture is as follows: dimethyl sulfoxide is added to a water bath, the water bath is heated to 75°C, then diethylenetriamine pentaacetic acid is added, the water bath is connected to a magnetic stirrer, the magnetic stirrer is set to a speed of 100 r / min, and the mixture is stirred at a constant temperature for 15 minutes, then the temperature is set to 110°C, 3-aminopropylmethyldimethoxysilane, methyl glycol chitosan, and N-hydroxysuccinimide are added, and the mixture is reacted at a constant temperature for 25 minutes. After cooling to 75°C, polyvinyl pyrrolidone is added, the temperature is set to 65°C, the magnetic stirrer speed is 150 r / min, and the mixture is stirred at a constant temperature for 3 hours. The obtained product and deionized water are added to a mixer, and the mixer is set to 500 r / min and stirred for 25 minutes to prepare a mixture, wherein the mass ratio of each raw material in the mixture is 100:5:7:11:3:1:210, and the mass ratio of the base material to the mixture is 1:1.7;

[0045] S3: Mixing process: mixing the base material and the admixture to obtain a powder;

[0046] The mixing method is as follows: the base material and the mixing agent are added to the mixer, the mixer is set to 500r / min and stirred for 35 minutes to obtain a slurry, the slurry is pumped into a spray drying tower for spray granulation treatment, the spray drying tower is set to an inlet temperature of 170°C, an outlet temperature of 85°C, an atomization pressure of 0.4MPa, and a feed rate of 15L / h to obtain a granular material, the granular material, nano-silicon dioxide, and nano-zirconium oxide are added to the mixer, the mixer is set to 700r / min and stirred for 45 minutes, the mixing treatment is completed, and a powder is obtained.

[0047] The particle sizes of nano-silicon dioxide and nano-zirconia are 20 nm, the mass of nano-silicon dioxide is 6% of the mass of the granular material, and the mass of nano-zirconia is 2% of the mass of the granular material.

[0048] The binder is silica sol.

[0049] Preparation of petroleum fracturing proppant: comprising the following steps: weighing zircon sand, quartz sand, clay, sodium hexametaphosphate, powder, bauxite powder, and binder as needed, adding them into a mixer, setting the mixer to 700 r / min and stirring for 45 minutes to prepare a mixture, adding the mixture into a disc granulator for granulation, the granulated particle size is 170 μm, and sintering the obtained product, setting the heating rate to 7°C / min, heating to 400°C, and keeping warm for 25 minutes, then setting the heating rate to 15°C / min, heating to 1250°C, and keeping warm for 25 minutes to prepare the petroleum fracturing proppant.

[0050] Example 3:

[0051] Raw material preparation: 10% quartz sand, 2% clay, 4% sodium hexametaphosphate, 16% powder, 2% bauxite powder, 6% binder, and the balance is supplemented by zircon sand to 100%;

[0052] The preparation of the powder comprises the following steps:

[0053] S1: base material preparation, the raw material of the base material is fly ash;

[0054] The base material preparation method is as follows: fly ash is subjected to magnetic separation and flotation treatment to remove impurities, and then screened. The particle size of the fly ash after screening is 300 μm. The screened fly ash is added to a muffle furnace for calcination. The calcination process is set to a heating rate of 20°C / min, and the temperature is raised to 900°C and kept warm for 50 minutes. After the calcination process is completed, the temperature is cooled to room temperature. The resulting product is added to a mixer, and sodium hydroxide solution is added to the mixer. The mixer is set to 600 r / min and stirred for 40 minutes. The resulting product is washed with deionized water, and then filtered and dried to obtain the base material. The mass of the sodium hydroxide solution is 3 times the mass of the screened fly ash, and the mass concentration of the sodium hydroxide solution is 6%.

[0055] S2: preparation of a mixture, wherein the raw materials of the mixture include dimethyl sulfoxide, diethylenetriamine pentaacetic acid, 3-aminopropylmethyldimethoxysilane, methyl glycol chitosan, N-hydroxysuccinimide, polyvinyl pyrrolidone, and deionized water;

[0056] The preparation method of the mixture is as follows: dimethyl sulfoxide is added to a water bath, the water bath is heated to 80°C, then diethylenetriamine pentaacetic acid is added, the water bath is connected to a magnetic stirrer, the magnetic stirrer is set to a speed of 120r / min, and constant temperature stirring is carried out for 20min, then the temperature is set to 120°C, 3-aminopropylmethyldimethoxysilane, methyl glycol chitosan, and N-hydroxysuccinimide are added, and the reaction is carried out at a constant temperature for 30min. After cooling to 80°C, polyvinyl pyrrolidone is added, the temperature is set to 70°C, the speed of the magnetic stirrer is 200r / min, and constant temperature stirring is carried out for 4h. The obtained product and deionized water are added to a mixer, and the mixer is set to 600r / min and stirred for 30min to prepare a mixture, wherein the mass ratio of each raw material in the mixture is 100:6:8:12:4:1.2:220, and the mass ratio of the base material to the mixture is 1:1.8;

[0057] S3: Mixing process: mixing the base material and the admixture to obtain a powder;

[0058] The mixing method is as follows: the base material and the mixing agent are added to the mixer, the mixer is set to 600 r / min and stirred for 40 minutes to obtain a slurry, the slurry is pumped into a spray drying tower for spray granulation treatment, the spray drying tower is set to an inlet temperature of 180°C, an outlet temperature of 90°C, an atomization pressure of 0.5 MPa, and a feed rate of 20 L / h to obtain a granular material, the granular material, nano-silicon dioxide, and nano-zirconium oxide are added to the mixer, the mixer is set to 800 r / min and stirred for 50 minutes, the mixing treatment is completed, and a powder is obtained.

[0059] The particle sizes of nano-silicon dioxide and nano-zirconia are 30 nm, the mass of nano-silicon dioxide is 7% of the mass of the granular material, and the mass of nano-zirconia is 3% of the mass of the granular material.

[0060] The binder is silica sol.

[0061] Preparation of petroleum fracturing proppant: comprising the following steps: weighing zircon sand, quartz sand, clay, sodium hexametaphosphate, powder, bauxite powder, and binder as needed, adding them into a mixer, setting the mixer to 800 r / min and stirring for 50 minutes to prepare a mixture, adding the mixture into a disc granulator for granulation, the granulated particle size is 200 μm, and sintering the obtained product, setting the heating rate to 10°C / min, heating to 500°C, and keeping warm for 30 minutes, then setting the heating rate to 20°C / min, heating to 1300°C, and keeping warm for 30 minutes to prepare the petroleum fracturing proppant.

[0062] Comparative Example 1: The difference between this comparative example and Example 1 is that this comparative example does not contain diethylenetriaminepentaacetic acid.

[0063] Comparative Example 2: The difference between this comparative example and Example 1 is that this comparative example does not contain nano-silicon dioxide and nano-zirconium oxide.

[0064] Comparative Example 3: The difference between this comparative example and Example 1 is that in this comparative example, an equal amount of fly ash is used to replace the powder.

[0065] Comparative Example 4: This comparative example differs from Example 1 in that this comparative example does not contain powder.

[0066] Performance test: The performance test was conducted on the petroleum fracturing proppants prepared in Example 1, Example 2, Example 3, Comparative Example 1, Comparative Example 2, Comparative Example 3 and Comparative Example 4. The test data are recorded in the following table:

[0067]

[0068] In the performance test, the test method in GB / T17431-2019 was used to test the compressive strength performance of the petroleum fracturing proppants prepared in Example 1, Example 2, Example 3, Comparative Example 1, Comparative Example 2, Comparative Example 3 and Comparative Example 4;

[0069] The test method in SY / T5108-2014 was used to test the crushing rate performance of the petroleum fracturing proppants prepared in Example 1, Example 2, Example 3, Comparative Example 1, Comparative Example 2, Comparative Example 3 and Comparative Example 4.

[0070] It can be seen that the strength performance of the petroleum fracturing proppants prepared in Comparative Examples 1, 2, 3, and 4 is lower than that of Examples 1, 2, and 3. This shows that in the preparation of petroleum fracturing proppants, the surface structure of fly ash can be optimized after high temperature and alkali treatment, dimethyl sulfoxide as a polar solvent can assist in the uniform dispersion of various components, 3-aminopropylmethyldimethoxysilane can improve the interface bonding between fly ash and other component materials, and enhance the adhesion between particulate materials. Diethylenetriaminepentaacetic acid and N-hydroxysuccinimide can synergistically chelate metal ions to form a compact three-dimensional network structure, thereby enhancing the stability of the various structural combinations in the petroleum fracturing proppants, thereby achieving the purpose of improving the strength performance of the petroleum fracturing proppants.

[0071] The addition of nano-silica and nano-zirconia can fill the micropores in the oil fracturing proppant system. After filling the micropores, it can inhibit the coarsening of grains, thereby refining the grain size after sintering and improving the density of the material. Through the combined spray drying treatment of the base material and the mixture, uniform spherical particles are formed after spray drying. The spherical particles can evenly distribute stress during the use of the fracturing proppant, reduce the breakage caused by local stress concentration, and further improve the strength performance of the oil fracturing proppant.

[0072] Comparison and analysis of the relevant data in the table show that the petroleum fracturing proppant prepared by the present invention not only has good compressive strength but also has excellent crushing rate. This shows that the petroleum fracturing proppant containing fly ash provided by the present invention has a broader market prospect and is more suitable for promotion.

[0073] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0074] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the present invention to the specific embodiments described. Obviously, many modifications and variations are possible based on the content of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A petroleum fracturing proppant containing fly ash, characterized in that: The invention comprises the following raw materials: zircon sand, quartz sand, clay, sodium hexametaphosphate, powder, bauxite powder, and binder, wherein the weight percentage of each raw material is: 8-10% quartz sand, 1-2% clay, 2-4% sodium hexametaphosphate, 12-16% powder, 1-2% bauxite powder, and 4-6% binder, and the balance is supplemented by zircon sand to 100%; The preparation of the powder comprises the following steps: S1: base material preparation, the raw material of the base material is fly ash; The base material preparation method comprises the following steps: removing impurities from fly ash through magnetic separation and flotation treatment, followed by screening treatment, wherein the particle size of the fly ash after screening is 200-300 μm, adding the screened fly ash into a muffle furnace for calcination treatment, setting the heating rate of the calcination treatment at 10-20° C. / min, heating to 800-900° C., and keeping the temperature for 30-50 minutes, and after the calcination treatment is completed, waiting for cooling to room temperature, adding the obtained product into a mixer, adding sodium hydroxide solution into the mixer, setting the mixer at 400-600 r / min and stirring for 30-40 minutes, washing the obtained product with deionized water, and then filtering and drying to obtain the base material; S2: preparing a mixture, wherein the raw materials of the mixture include dimethyl sulfoxide, diethylenetriamine pentaacetic acid, 3-aminopropylmethyldimethoxysilane, methyl glycol chitosan, N-hydroxysuccinimide, polyvinyl pyrrolidone, and deionized water; The preparation method of the mixture is as follows: dimethyl sulfoxide is added to a water bath, the water bath is heated to 70-80° C., diethylenetriamine pentaacetic acid is added, the water bath is connected to a magnetic stirrer, the magnetic stirrer is set to a speed of 80-120 r / min, constant temperature stirring is performed for 10-20 minutes, the temperature is then set to 100-120° C., 3-aminopropylmethyldimethoxysilane, methyl glycol chitosan, and N-hydroxysuccinimide are added, the reaction is carried out at a constant temperature for 20-30 minutes, and after the temperature is cooled to 70-80° C., polyvinyl pyrrolidone is added. The temperature is set at 60-70° C., the speed of the magnetic stirrer is 100-200 r / min, and the mixture is stirred at constant temperature for 2-4 hours. The obtained product and deionized water are added to a mixer, and the mixer is set at 400-600 r / min and stirred for 20-30 minutes to prepare a mixture. The mass ratio of the raw materials in the mixture is 100: (4-6): (6-8): (10-12): (2-4): (0.8-1.2): (200-220), and the mass ratio of the base material to the mixture is 1: (1.6-1.8); S3: Mixing treatment: the base material and the admixture are mixed to obtain a powder.

2. The petroleum fracturing proppant containing fly ash according to claim 1, characterized in that: The mass of the sodium hydroxide solution is 2 to 3 times the mass of the fly ash after screening, and the mass concentration of the sodium hydroxide solution is 4 to 6%.

3. The petroleum fracturing proppant containing fly ash according to claim 1, characterized in that: The mixing method comprises the following steps: adding a base material and a mixing agent into a mixer, setting the mixer at 400 to 600 r / min and stirring for 30 to 40 minutes to obtain a slurry, pumping the slurry into a spray drying tower for spray granulation treatment, setting the inlet temperature of the spray drying tower to 160 to 180° C., the outlet temperature to 80 to 90° C., the atomization pressure to 0.3 to 0.5 MPa, and the feed rate to 10 to 20 L / h to obtain a granular material, adding the granular material, nano-silicon dioxide, and nano-zirconium oxide into the mixer, setting the mixer at 600 to 800 r / min and stirring for 40 to 50 minutes, completing the mixing treatment, and obtaining a powder.

4. The petroleum fracturing proppant containing fly ash according to claim 3, characterized in that: The particle sizes of nano silicon dioxide and nano zirconium oxide are 10-30 nm, the mass of nano silicon dioxide is 5-7% of the mass of the particle material, and the mass of nano zirconium oxide is 1-3% of the mass of the particle material.

5. The petroleum fracturing proppant containing fly ash according to claim 1, characterized in that: The binder is silica sol.

6. A method for preparing a petroleum fracturing proppant containing fly ash according to claim 1, characterized in that: The method comprises the following steps: weighing zircon sand, quartz sand, clay, sodium hexametaphosphate, powder, bauxite powder and binder as needed, adding the mixture into a mixer, setting the mixer to 600-800 r / min and stirring for 40-50 min to obtain a mixture, adding the mixture into a disc granulator for granulation, wherein the granulated particle size is 150-200 μm, sintering the obtained product, setting the heating rate to 5-10° C. / min, heating to 300-500° C., keeping the temperature for 20-30 min, then setting the heating rate to 10-20° C. / min, heating to 1200-1300° C., keeping the temperature for 20-30 min, and obtaining an oil fracturing proppant.

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