A high-strength fracturing proppant prepared from alumina and its preparation method

Abstract

The present invention relates to the field of preparation of high-strength fracturing proppants, and particularly relates to a high-strength fracturing proppant prepared from alumina and a preparation method thereof, which is mainly made of the following raw materials in parts by weight: 50-60 parts of bauxite, 20-30 parts of calcined bauxite, 3-8 parts of coal gangue, 8-13 parts of alumina tailings, 3-7 parts of iron ore, and 7-10 parts of a reinforcing agent; the preparation method of the reinforcing agent comprises the following steps: S11: taking zirconia and yttrium oxide, crushing and mixing them, and then sintering them at 1500-1700 °C to prepare a premixed material; S12: mixing the premixed material prepared in step S11 and calcium carbonate according to a mass ratio of (4-6):(6-7) to obtain the reinforcing agent. This application has the advantage of improving the mechanical properties of the proppant prepared from bauxite.

Description

Technical Field

[0001] The present invention relates to the field of preparation of high-strength fracturing proppants, and particularly relates to a high-strength fracturing proppant prepared from alumina and a preparation method thereof. Background Art

[0002] Proppants are artificial high-strength ceramic particles with a certain particle size and gradation. Proppants are mainly used in the development of deep oil and gas wells to prevent the closure of fractures after oil and gas extraction, help form highly permeable channels in the developed deep oil and gas wells, and assist in the extraction of oil and gas; good proppants can not only increase the production of oil and gas, but also extend the service life of oil and gas wells; existing proppants are usually made from bauxite as raw materials, by grinding bauxite and other raw materials into powder and sintering. The main component in bauxite is alumina. The proppants prepared from bauxite can maintain a relatively high conductivity under high closure pressure, so they are widely used. At the same time, the proppants prepared from bauxite also have the characteristics of high temperature resistance, high pressure resistance and corrosion resistance, so they are widely favored.

[0003] In the above related technologies, the inventor believes that: when the existing proppants mainly made from bauxite are prepared, it is difficult to discharge the internal pores during the calcination process, which is likely to cause the internal structure of the prepared alumina proppants to be loose and the compactness to be insufficient, thereby affecting the mechanical properties of the prepared alumina proppants. Summary of the Invention

[0004] In order to improve the mechanical properties of proppants prepared from bauxite, the present application provides a high-strength fracturing proppant prepared from alumina and a preparation method thereof.

[0005] In a first aspect, a high-strength fracturing proppant prepared from alumina provided by the present application adopts the following technical solution:

[0006] A high-strength fracturing proppant prepared from alumina is mainly made from the following raw materials in parts by weight: 50-60 parts of bauxite, 20-30 parts of calcined bauxite, 3-8 parts of coal gangue, 8-13 parts of alumina tailings, 3-7 parts of iron ore, 7-10 parts of reinforcing agent; the preparation method of the reinforcing agent includes the following steps:

[0007] S11: Take zirconia and yttrium oxide, crush and mix them, and then place them at 1500-1700 °C for sintering to prepare a premix;

[0008] S12: Mix the premix obtained in step S11 and calcium carbonate in a mass ratio of (4-6):(6-7) to obtain the product.

[0009] By adopting the above technical solution, the above raw materials are combined to prepare a proppant. Since bauxite contains a large amount of alumina, a relatively high calcination temperature is required for alumina to achieve a dense structure during the calcination process. However, the relatively high calcination temperature makes it difficult for the internal pores of alumina to be discharged during the calcination process, resulting in a loose internal structure of the prepared proppant, affecting its mechanical properties and increasing the crushing rate when stressed. By adding a reinforcing agent, during the preparation of the reinforcing agent, due to the insufficient stability of zirconia, through the combination of yttrium oxide and zirconia, yttrium oxide enters the lattice of zirconia during the calcination process, undergoes a solid solution reaction, and generates a pre-mixture with a tetragonal crystal phase. After adding it to the proppant, when the proppant is stressed, the pre-mixture with a tetragonal crystal phase transforms into a monoclinic crystal phase under stress mutagenesis. The monoclinic crystal phase can improve the fracture toughness and flexural strength of the proppant, enhancing and toughening the proppant. At the same time, calcium carbonate is added to the reinforcing agent, which combines with a large amount of silica in coal gangue to form a three-phase crystalline product of mullite phase, anorthite phase, and corundum phase. With the addition of calcium carbonate, the mullite crystal phase gradually refines and interweaves into a network structure. At the same time, calcium carbonate promotes the formation of the corundum phase, refines the crystal phase structure inside the proppant, improves the compactness of the internal structure of the proppant, and thus improves the mechanical properties of the prepared proppant.

[0010] However, when the amount of calcium carbonate used is excessive, since calcium carbonate can promote the formation of a new anorthite phase, and the strength of the new anorthite phase is lower than that of the mullite phase and the corundum phase, it will cause the mechanical properties of the prepared proppant to decline. Therefore, by adjusting the amount of calcium carbonate used, the mechanical properties of the proppant can be improved.

[0011] Optionally, the mass ratio of zirconia to yttrium oxide in step S1 is (8 - 11):(1 - 2).

[0012] By adopting the above technical solution, by adjusting the mass ratio of zirconia to yttrium oxide, when the content of yttrium oxide is insufficient, the stabilizing effect on zirconia is insufficient; however, when too much yttrium oxide is used, the number of oxygen vacancies generated by the solid solution reaction increases, which will migrate to the grain boundary and accumulate to form a pore group, resulting in a loose internal structure and a decrease in density of the prepared proppant, affecting the mechanical strength of the prepared proppant. By adjusting the mass ratio of yttrium oxide to zirconia, the prepared reinforcing agent has a good reinforcing effect on the proppant.

[0013] Optionally, the bauxite and alumina tailings are pretreated before use, and the pretreatment includes the following steps: 1) Mix the bauxite, alumina tailings, water, and titanium sulfate to prepare a pre-mixture.

[0014] 2) Drop ammonia water into the pre-mixture prepared in step 1), adjust the pH value of the pre-mixture to 9 - 11, filter, and dry to obtain the product.

[0015] By adopting the above technical solution, since the sintering temperature requirements for bauxite and alumina tailings are relatively high and the sintering difficulty is relatively large; after mixing bauxite and alumina tailings with water and titanium sulfate, under the action of ammonia water, titanium sulfate is used as a precursor to wrap and modify alumina particles, improving the sintering activity of bauxite and alumina tailings, reducing their sintering temperature, and reducing the preparation difficulty of the proppant.

[0016] In a second aspect, the present application provides a method for preparing a high-strength fracturing proppant prepared from alumina:

[0017] A method for preparing a high-strength fracturing proppant prepared from alumina mainly includes the following steps:

[0018] S1: Grind bauxite and calcine it at 800 - 1000 °C to prepare a pretreated material;

[0019] S2: Crush bauxite, coal gangue, alumina tailings, iron ore, and a reinforcing agent and prepare them into a powder;

[0020] S3: Mix the powder obtained in step S2 with the pretreated material obtained in step S1, add water during the mixing process, and prepare a pretreated ball through a semi-wet process, and then sinter to obtain.

[0021] By adopting the above technical solution, first calcine bauxite at 800 - 1000 °C, so that the diaspore in the bauxite undergoes a dehydration reaction to form pseudo-corundum. After the pseudo-corundum is mixed with raw materials such as coal gangue, it can be sintered to form a structure containing a large number of rod-shaped mullite crystals. The intersecting rod-shaped mullite crystals can play a good toughening effect, and at the same time improve the crystallization degree during the sintering process of the proppant, making the structure of the generated proppant more dense and the mechanical strength improved.

[0022] Optionally, before mixing the powder with the pretreated material in step S3, carbon black is also added to the powder; the mass ratio of the carbon black to the bauxite is (1 - 3):(15 - 22).

[0023] By adopting the above technical solution, the dense crystalline structure inside the proppant results in a relatively large density, and thus a relatively large mass. However, the proppant with a large mass settles during use, resulting in a poor filling effect on the formation and a large dosage. Therefore, carbon black is added as a pore-forming agent. During the preparation process, the carbon black is sintered to form uniform pores in the proppant. At the same time, the burned-out remaining powder can fill the pores in the proppant, reducing the mass of the proppant while trying to maintain good mechanical properties of the proppant. By adjusting the addition amount of carbon black, when the addition amount of carbon black is small, the pore-forming effect on the proppant is insufficient, affecting the later use of the proppant. However, when too much carbon black is added, too many pores are easily generated, affecting the mechanical properties of the prepared proppant.

[0024] Optionally, during the process of grinding the bauxite in step S1, an auxiliary agent is also added to the bauxite; the auxiliary agent is at least one of manganese dioxide and titanium dioxide; the mass ratio of the auxiliary agent to the bauxite is 1:(21 - 24).

[0025] By adopting the above technical solution, manganese dioxide is added as an auxiliary agent. Since the radius of manganese ions in manganese dioxide is similar to that of Al 3+ in the corundum phase, a solid solution reaction can occur at high temperature, enabling manganese ions to replace Al 3+ to form a solid solution. At the same time, due to the different chemical valence states of manganese ions and Al 3+ , lattice distortion of alumina will occur, forming an activated lattice, reducing the sintering temperature of the proppant, improving the compactness inside the proppant, and thus improving the mechanical properties of the proppant. After titanium dioxide is added to the raw materials, it can combine with bauxite to generate Al 2 Ti0 5 , refine the crystal grains of alumina, and at the same time produce a solid solution reaction to promote the low-temperature sintering of the proppant, making the internal structure of the proppant more compact. Both manganese dioxide and titanium dioxide can assist in the calcination of bauxite and improve the mechanical properties of the subsequently prepared proppant.

[0026] Optionally, the auxiliary agent is composed of manganese dioxide and titanium dioxide in a mass ratio of (2 - 3):(3 - 5).

[0027] By adopting the above technical solution, manganese dioxide and titanium dioxide are combined to prepare an auxiliary agent. Manganese dioxide reduces the sintering temperature of bauxite and improves the compactness of the internal structure of the proppant. At the same time, in combination with titanium dioxide, titanium dioxide combines with bauxite to generate Al 2 Ti0 5 , Al 2 Ti0 5 can fill the pores between alumina crystals, inhibit the growth of alumina crystals, and promote the more uniform crystallization morphology inside the proppant. The combination of the two further improves the mechanical properties of the prepared proppant.

[0028] Optionally, the sintering temperature of the pre-treated balls in step S3 is 1100-1500°C.

[0029] By adopting the above technical solution, as the sintering temperature of the pre-treated balls increases, the alumina crystals continuously grow, the specimen tends to be densified, and the mechanical properties are improved; when the sintering temperature continues to increase, the number of small pores formed inside the proppant increases, and at the same time, Al 2 Ti0 5 is continuously generated and fills between the alumina. The small pores cannot be discharged under the extrusion of Al 2 Ti0 5 , making the small pores easily converge into pore clusters, affecting the mechanical strength of the proppant; by adjusting the sintering temperature of the pre-treated balls, the prepared proppant has good mechanical properties.

[0030] Optionally, when adding the carbon black to the powder in step S2, first mix the carbon black with water evenly.

[0031] By adopting the above technical solution, the carbon black is mixed with water before use to generate a fluid substance, which promotes the more uniform distribution of the carbon black in the powder, improves the uniformity of the pore distribution inside the prepared proppant, and further improves the mechanical properties of the prepared proppant.

[0032] In summary, the present application has the following beneficial effects:

[0033] In the present application, an enhancer is added to the raw materials of the proppant. During the preparation process of the enhancer, zirconia and yttria are mixed and calcined to generate a pre-mixture with a tetragonal phase. Then the pre-mixture is mixed with calcium carbonate. When the tetragonal phase crystals of the pre-mixture are stressed, the tetragonal phase transforms into a monoclinic phase, improving the strength and toughness of the prepared proppant; at the same time, calcium carbonate can refine the crystal phase structure inside the proppant and improve the denseness of the internal structure of the proppant, jointly improving the mechanical properties of the alumina-containing proppant. Detailed Embodiments

[0034] The following further describes the present application in detail with reference to examples and comparative examples;

[0035] The raw materials of the examples and comparative examples of the present application are all commercially available except as otherwise specified.

[0036] Preparation Example

[0037] Preparation Example 1 of Enhancer

[0038] S11: Take zirconia and yttria, put them into a grinding machine to grind, crush and mix, then place them in a sintering kiln and sinter at 1600°C for 3h, and take out and cool to prepare a pre-mixed material; the mass ratio of the used zirconia to yttria is 8:2;

[0039] S12: Mix the premix obtained in step S11 and calcium carbonate in a mass ratio of 4:7 to obtain the product.

[0040] Enhancer Preparation Example 2

[0041] The difference between this enhancer preparation example and Enhancer Preparation Example 1 is that the mass ratio of the premix to calcium carbonate used in step S12 is 6:6.

[0042] Enhancer Preparation Example 3

[0043] The difference between this enhancer preparation example and Enhancer Preparation Example 1 is that the mass ratio of the premix to calcium carbonate used in step S12 is 5:6.5.

[0044] Enhancer Preparation Example 4

[0045] The difference between this enhancer preparation example and Enhancer Preparation Example 3 is that the mass ratio of zirconia to yttria used in step S11 is 11:1.

[0046] Enhancer Preparation Example 5

[0047] The difference between this enhancer preparation example and Enhancer Preparation Example 3 is that the mass ratio of zirconia to yttria used in step S11 is 10:1.5.

[0048] Examples

[0049] Example 1

[0050] The high-strength fracturing proppant prepared using alumina in this example mainly includes the following raw materials: 50 kg of bauxite, 20 kg of calcined bauxite, 3 kg of coal gangue, 8 kg of alumina tailings, 3 kg of iron ore, and 7 kg of enhancer; the enhancer used is prepared according to Enhancer Preparation Example 1;

[0051] The preparation method of the high-strength fracturing proppant prepared using alumina in this example mainly includes the following steps;

[0052] S1: After grinding the above-mentioned weight of bauxite, place it in a sintering kiln, set the temperature in the sintering kiln to 900 °C, and calcine for 2 h to prepare a pretreatment material;

[0053] S2: Ball mill and pulverize the above-mentioned weight of calcined bauxite, coal gangue, alumina tailings, iron ore, and enhancer to prepare a powder;

[0054] S3: Mix the powder obtained in step S2 with the pretreated material obtained in step S1, continuously add water during the mixing process, prepare a pre-treated ball through a semi-wet process, sinter the pre-treated ball at 1100 °C for 3 h, take it out and cool it, and then dry it to obtain the product; the mass ratio of the water used to the powder is 1:5.

[0055] Example 2

[0056] The difference between the preparation method of the high-strength fracturing proppant prepared from alumina in this example and that in Example 1 is that the high-strength fracturing proppant prepared from alumina mainly includes the following raw materials: 60 kg of bauxite, 30 kg of calcined bauxite, 8 kg of coal gangue, 13 kg of alumina tailings, 7 kg of iron ore, and 10 kg of reinforcing agent.

[0057] Example 3

[0058] The difference between the preparation method of the high-strength fracturing proppant prepared from alumina in this example and that in Example 1 is that the high-strength fracturing proppant prepared from alumina mainly includes the following raw materials: 55 kg of bauxite, 25 kg of calcined bauxite, 5 kg of coal gangue, 10 kg of alumina tailings, 5 kg of iron ore, and 8 kg of reinforcing agent.

[0059] Example 4

[0060] The difference between the preparation method of the high-strength fracturing proppant prepared from alumina in this example and that in Example 3 is that the calcined bauxite and alumina tailings used are pretreated before use, and the pretreatment includes the following steps:

[0061] 1) Crush the calcined bauxite and alumina tailings and then mix them to prepare a mixed powder. Take a mixing barrel and put the mixed powder, water, and titanium sulfate into the mixing barrel together for mixing to prepare a pre-mixture; the mass ratio of the mixed powder, water, and titanium sulfate used is 1:2:0.1;

[0062] 2) Drop ammonia water into the pre-mixture obtained in step 1), adjust the pH value of the pre-mixture to 10, stir evenly, filter, and dry to obtain the product.

[0063] Example 5

[0064] The difference between the preparation method of the high-strength fracturing proppant prepared from alumina in this example and that in Example 4 is that during the grinding process of bauxite in step S1, an additive is added to the bauxite. The additive used is manganese dioxide, and the mass ratio of the additive to bauxite is 1:23.

[0065] Example 6

[0066] The preparation method of the high-strength fracturing proppant prepared from alumina in this embodiment is different from that in Embodiment 5 in that, in step S1, during the grinding of bauxite, an auxiliary agent is added to the bauxite, and the auxiliary agent used is titanium dioxide.

[0067] Example 7

[0068] The preparation method of the high-strength fracturing proppant prepared from alumina in this embodiment is different from that in Embodiment 5 in that, in step S1, during the grinding of bauxite, an auxiliary agent is added to the bauxite, and the auxiliary agent used is composed of manganese dioxide and titanium dioxide in a mass ratio of 2:5.

[0069] Example 8

[0070] The preparation method of the high-strength fracturing proppant prepared from alumina in this embodiment is different from that in Embodiment 5 in that, in step S1, during the grinding of bauxite, an auxiliary agent is added to the bauxite, and the auxiliary agent used is composed of manganese dioxide and titanium dioxide in a mass ratio of 3:3.

[0071] Example 9

[0072] The preparation method of the high-strength fracturing proppant prepared from alumina in this embodiment is different from that in Embodiment 5 in that, in step S1, during the grinding of bauxite, an auxiliary agent is added to the bauxite, and the auxiliary agent used is composed of manganese dioxide and titanium dioxide in a mass ratio of 2.5:4.

[0073] Example 10

[0074] The preparation method of the high-strength fracturing proppant prepared from alumina in this embodiment is different from that in Embodiment 9 in that, in this embodiment, the sintering temperature of the pretreated balls in step S3 is 1500 °C.

[0075] Example 11

[0076] The preparation method of the high-strength fracturing proppant prepared from alumina in this embodiment is different from that in Embodiment 9 in that, in this embodiment, the sintering temperature of the pretreated balls in step S3 is 1300 °C.

[0077] Example 12

[0078] The preparation method of the high-strength fracturing proppant prepared from alumina in this embodiment is different from that in Embodiment 11 in that, before mixing the powder material with the pretreated material in step S3, carbon black is also added to the powder material; the mass ratio of the carbon black used to the bauxite is 2:21.

[0079] Example 13

[0080] The preparation method of the high-strength fracturing proppant prepared from alumina in this example is different from that in Example 12 in that the enhancer used in step S2 in this example is prepared in Enhancer Preparation Example 2.

[0081] Example 14

[0082] The preparation method of the high-strength fracturing proppant prepared from alumina in this example is different from that in Example 12 in that the enhancer used in step S2 in this example is prepared in Enhancer Preparation Example 3.

[0083] Example 15

[0084] The preparation method of the high-strength fracturing proppant prepared from alumina in this example is different from that in Example 12 in that the enhancer used in step S2 in this example is prepared in Enhancer Preparation Example 4.

[0085] Example 16

[0086] The preparation method of the high-strength fracturing proppant prepared from alumina in this example is different from that in Example 12 in that the enhancer used in step S2 in this example is prepared in Enhancer Preparation Example 5.

[0087] Example 17

[0088] The preparation method of the high-strength fracturing proppant prepared from alumina in this example is different from that in Example 16 in that the carbon black used in step S3 in this example is first mixed evenly with water before being mixed with the powder; the mass ratio of the water used to the carbon black is 3:1.

[0089] Comparative Example

[0090] Comparative Example 1

[0091] The preparation method of the high-strength fracturing proppant prepared from alumina in this comparative example is different from that in Example 1 in that the enhancer in the raw materials used is calcium carbonate.

[0092] Comparative Example 2

[0093] The preparation method of the high-strength fracturing proppant prepared from alumina in this comparative example is different from that in Example 1 in that the enhancer in the raw materials used is zirconia.

[0094] Comparative Example 3

[0095] The preparation method of the high-strength fracturing proppant prepared from alumina in this comparative example is different from that in Example 1 in that the enhancer in the raw materials used is yttrium oxide.

[0096] Detection Method

[0097] The high-strength fracturing proppants were prepared according to the preparation methods of the high-strength fracturing proppants prepared using alumina in Examples 1-17 and Comparative Examples 1-3. The particle size of the proppants prepared in each experimental method was 40 mesh; 1000 proppants were taken as experimental samples in each group of experiments; the experimental samples were tested for anti-breakage ability according to the experimental methods in "Performance Indexes and Test Recommended Methods for Fracturing Proppants" in SY / T5108-2006, the breakage rate was calculated, and the data were recorded to obtain Table 1;

[0098] Table 1 Breakage Rates of High-Strength Fracturing Proppants Prepared in Examples 1-17 and Comparative Examples 1-3

[0099] Serial number Breakage rate (%) Example 1 8.5 Example 2 8.8 Example 3 8.3 Example 4 7.7 Example 5 7.2 Example 6 7.4 Example 7 7.0 Example 8 6.8 Example 9 6.5 Example 10 6.8 Example 11 6.2 Example 12 6.3 Example 13 6.4 Example 14 6.1 Example 15 5.8 Example 16 5.6 Example 17 5.4 Comparative Example 1 12.9 Comparative Example 2 13.7 Comparative Example 3 14.5

[0100] Combined with Examples 1-9 and Table 1, it can be seen that by adjusting the dosages of various raw materials in the proppant, and before using bauxite and alumina tailings in the raw materials, first mixing them with water and titanium sulfate, then dropping ammonia water, filtering and drying. After such pretreatment, titanium sulfate is used as a precursor to wrap the alumina in bauxite and alumina tailings, improving the sintering activity of the subsequent alumina, thereby reducing the subsequent sintering temperature, making it easier for the gas to be discharged during sintering, and improving the density and uniformity of the internal structure of the proppant; at the same time, adjusting the additives added during the grinding of bauxite. When the additives used are composed of manganese dioxide and titanium dioxide according to a mass ratio of 2.5:4, manganese dioxide is used to reduce the sintering temperature of bauxite, and in cooperation with titanium dioxide, generate Al 2 Ti0 5 Fill into the pores between alumina crystals, refine the alumina grains generated during the calcination of bauxite, further improve the density of the internal structure of the proppant, thereby improving the mechanical properties and reducing the breakage rate of the proppant when stressed;

[0101] Combined with Examples 9-12 and Table 1, it can be seen that by adjusting the sintering temperature of the proppant, as the temperature continuously increases, the internal structure of the proppant becomes more dense. At the same time, it also avoids that too high a temperature causes Al 2 Ti0 5 to continuously generate and squeeze the pores in the proppant, causing the pores in the proppant to gather to form pore groups, affecting the uniformity of the internal structure of the proppant, making the proppant prone to breakage when stressed, and affecting the use of the proppant; adding carbon black as a pore-forming agent to reduce the mass of the proppant, facilitating subsequent use, and filling the internal gaps of the proppant with the powder after sintering of carbon black, so that while reducing the density of the proppant, the mechanical strength of the proppant is also maintained as much as possible;

[0102] As can be seen from Examples 13 - 17, Comparative Examples 1 - 3 and Table 1, sintering yttrium oxide and zirconia causes a solid solution reaction between the two, generating a premix with a tetragonal phase. After adding the premix and calcium carbonate as reinforcing agents to the proppant, when stressed, the tetragonal phase in the reinforcing agent transforms into a monoclinic phase, and this process absorbs the stress received by the proppant, achieving the effect of enhancing and toughening the proppant. At the same time, calcium carbonate refines the grains in the proppant, improving the uniformity of the crystal phase structure distribution inside the proppant. With the cooperation of the reinforcing agent and other raw materials, the mechanical properties of the proppant are further improved. At the same time, mixing carbon black with water before use improves the uniformity of the distribution of carbon black in other raw materials. As a result, the prepared proppant has good porosity and good mechanical strength, so that the crushing rate of the proppant when stressed is relatively low.

[0103] This specific embodiment is only an interpretation of the present application and does not limit the present application. After reading this specification, those skilled in the art can make modifications to this embodiment without creative contributions as needed, but as long as it is within the scope of the claims of the present application, it is protected by the patent law.

Claims

1. A preparation method of a high-strength fracturing proppant prepared from alumina, characterized in that: mainly includes the following steps: S1: Grind bauxite and calcine it at 800 - 1000 °C to prepare a pretreated material; S2: Crush bauxite, coal gangue, alumina tailings, iron ore and a reinforcing agent to prepare a powder; S3: Mix the powder obtained in step S2 with the pretreated material obtained in step S1, add water during the mixing process, and prepare a pretreated ball through a semi-wet process, then sinter it to obtain; Before mixing the powder with the pretreated material in step S3, carbon black is also added to the powder; the mass ratio of the carbon black to bauxite is (1 - 3):(20 - 22); when adding the carbon black to the powder in step S2, first mix the carbon black and water evenly; The high-strength fracturing proppant is made from the following raw materials in parts by weight: 50 - 60 parts of bauxite, 20 - 30 parts of bauxite, 3 - 8 parts of coal gangue, 8 - 13 parts of alumina tailings, 3 - 7 parts of iron ore, 7 - 10 parts of a reinforcing agent, carbon black, and the mass ratio of the carbon black to bauxite is (1 - 3):(20 - 22); The preparation method of the reinforcing agent includes the following steps: S11: Take zirconia and yttrium oxide, crush and mix them, and place them at 1500 - 1700 °C for sintering to prepare a premixed material; the mass ratio of the zirconia to yttrium oxide is (8 - 11):(1 - 2); S12: Mix the premixed material obtained in step S11 and calcium carbonate in a mass ratio of (4 - 6):(6 - 7) to obtain.

2. The preparation method of the high-strength fracturing proppant prepared from alumina according to claim 1, characterized in that: During the process of grinding the bauxite in step S1, an auxiliary agent is also added to the bauxite; the auxiliary agent is composed of manganese dioxide and titanium dioxide in a mass ratio of (2 - 3):(3 - 5); the mass ratio of the auxiliary agent to bauxite is 1:(21 - 24).

3. The preparation method of the high-strength fracturing proppant prepared from alumina according to claim 1 or 2, characterized in that: The sintering temperature of the pretreated ball in step S3 is 1100 - 1500 °C.

4. The preparation method of the high-strength fracturing proppant prepared from alumina according to claim 1, characterized in that: The bauxite and alumina tailings are pretreated before use, and the pretreatment includes the following steps: 1) Mix bauxite, alumina tailings with water and titanium sulfate to prepare a premixed material; 2) Drop ammonia water into the premixed material obtained in step 1), adjust the pH value of the premixed material to 9 - 11, filter, and dry to obtain.