A fracturing proppant containing barium residue and a method for preparing the same

Abstract

The present application relates to oil and gas deep well exploitation and building material technical field, especially to a kind of barium slag containing fracturing proppant and preparation method thereof.The barium slag containing fracturing proppant provided by the present application includes the following mass fraction of components: barium slag 60-70%, desulfurization gypsum 15-25%, quartz sand 0-15%, bentonite 1-7%, and the sum of the mass fraction of the above components is 100%.The present application provides the better dosage of barium slag and desulfurization gypsum in low aluminum system, simplifies the raw material composition of the barium slag containing fracturing proppant and desulfurization gypsum, and improves the performance of fracturing proppant to a greater extent.The composition of fracturing proppant is simple, the preparation method is simple, and the cost of industrial application is reduced.Meanwhile, the leaching concentration of heavy metal ions in the fracturing proppant system of the present application is all lower than the drinking water standard, so as to solve the harmless and resource utilization problems of industrial hazardous waste and industrial solid waste, promote the collaborative resource utilization and environmental protection of solid waste and hazardous waste.

Description

Technical Field

[0001] This invention relates to the fields of deep well extraction of oil and gas and building materials technology, and in particular to a barium slag-containing fracturing proppant and its preparation method. Background Technology

[0002] Barium slag is a byproduct of barite refining, particularly the carbothermic reduction of barite, with approximately 0.8 to 1.0 tons of barium slag generated per ton of barite produced. Barium slag primarily contains acid-soluble and water-soluble barium, with a high barium ion content, making it toxic and classified as HW47 hazardous waste. Currently, landfilling is the main method for disposing of barium slag. However, landfilling not only occupies significant land resources but also pollutes the environment. In particular, it is prone to spontaneous combustion at high temperatures, releasing toxic gases. Rainwater infiltration produces large amounts of yellow wastewater containing sulfides, which flows into surface and groundwater, polluting water bodies. Furthermore, the barium sulfide and acid-soluble barium in the slag are toxic to the soil. Existing technologies for the comprehensive utilization of barium slag mainly focus on building materials and chemical products, but these technologies are complex, and the actual consumption of barium slag is limited. Therefore, there is an urgent need to develop and implement innovative technologies to effectively mitigate the environmental pollution caused by barium slag storage.

[0003] Fracturing proppant is a widely used material in oilfield development, primarily used for downhole support operations to increase oil and gas production. The main raw materials for fracturing proppant include high-quality bauxite, high-alumina, and high-silicon materials; however, these raw materials are scarce and expensive, keeping the cost of fracturing proppant high. Utilizing waste barium slag to prepare ultra-low-cost fracturing proppant can not only solve the problem of harmless and resource-based treatment of industrial hazardous waste (barium slag), promoting the coordinated resource utilization of solid and hazardous waste and environmental protection, but also provide ultra-low-cost fracturing proppant for hydraulic fracturing, laying the foundation for engineering applications. However, existing barium slag-containing fracturing proppants have the following problems: a high proportion of barium slag has not been achieved in the preparation of fracturing proppant. Summary of the Invention

[0004] The purpose of this invention is to provide a fracturing proppant containing barium slag and its preparation method, so as to achieve the harmless and resource-based utilization of barium slag.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0006] This invention provides a barium slag-containing fracturing proppant, comprising the following components by mass fraction:

[0007] The composition consists of 60-70% barium slag, 15-25% desulfurized gypsum, 0-15% quartz sand, and 1-7% bentonite, with the sum of the mass fractions of the above components being 100%.

[0008] Optionally, the chemical composition of the barium slag, by weight, includes: 30-40 parts SiO2, 5-35 parts BaO2, 15-25 parts SO3, 3-8 parts Fe2O, 1-4 parts Na2O, 1-4 parts Al2O3, 1-5 parts CaO, 0-1 parts K2O, 0-1 parts MgO, 0-1 parts MnO, 0-1 parts TiO2, and 0-1 parts P2O5.

[0009] The specific surface area of ​​the barium slag is greater than or equal to 400 m². 2 / kg.

[0010] Optionally, the chemical composition of the desulfurized gypsum, by weight, includes: 40-55 parts CaO, 40-50 parts SO3, 0-2 parts MgO, 0-1.5 parts SiO2, 0-1 parts Al2O3, and 0-1 parts Fe2O3.

[0011] The specific surface area of ​​the desulfurized gypsum is greater than or equal to 450 m². 2 / kg.

[0012] Optionally, the chemical composition of the quartz sand, by weight, includes: 95-99 parts SiO2, 0-1 parts Fe2O3, 0-1 parts CaO, 0-1 parts Al2O3, 1-2 parts MgO, 0-1 parts TiO2, 0-1 parts ZrO2, 0-1 parts Na2O, and 0-1 parts K2O.

[0013] The specific surface area of ​​the quartz sand is greater than or equal to 450 m². 2 / kg.

[0014] Optionally, the chemical composition of the bentonite, by weight, includes: 60-70 parts SiO2, 15-25 parts Al2O3, 1-5 parts Na2O, 1-2 parts MgO, 0-1 parts CaO, and 1-2 parts Fe2O3.

[0015] The specific surface area of ​​the bentonite is greater than or equal to 450 m². 2 / kg.

[0016] This invention also provides a method for preparing the above-mentioned barium slag-containing fracturing proppant, comprising the following steps:

[0017] The barium slag, desulfurized gypsum, quartz sand and bentonite are mixed and then successively ground, granulated and sintered to obtain the fracturing proppant containing barium slag.

[0018] Optionally, the particle size of the mixture of barium slag, desulfurized gypsum, quartz sand and bentonite after grinding is 500 to 1000 mesh.

[0019] Optionally, the particle size of the pellet obtained by granulation is 20 to 70 mesh.

[0020] Optionally, the sintering heating rate is 6-10℃ / min, the temperature is 1020-1100℃, and the holding time is 1-3h.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The ultra-low cost fracturing proppant of the present invention uses barium slag to replace traditional high-alumina and high-silicon raw materials, fully solidifies free barium with desulfurized gypsum, and uses desulfurized gypsum, quartz sand and bentonite in combination to prepare ultra-low cost fracturing proppant, so that barium slag and desulfurized gypsum are utilized to the maximum extent, greatly reducing the cost of raw materials, and the utilization rate of barium slag is higher.

[0023] (2) This invention determines the optimal sintering parameters for preparing fracturing proppant with the best performance (fracture rate and leaching safety performance), and provides reference data on the changes in chemical composition, including Ba content, and heavy metal leaching concentration of barium slag-based fracturing proppant under different ratios of barium slag and desulfurized gypsum.

[0024] (3) This invention provides an optimal dosage of barium slag and desulfurized gypsum in a low-aluminum system, simplifies the raw material composition of fracturing proppant containing barium slag and desulfurized gypsum, so as to improve the performance of fracturing proppant to a greater extent. The fracturing proppant has a simple composition and a simple preparation method, which reduces the cost of industrial application.

[0025] (4) The leaching concentration of heavy metal ions in the fracturing proppant system of this invention is lower than that of drinking water, thus solving the problem of harmless and resource-based treatment of industrial hazardous waste (barium slag) and industrial solid waste (desulfurized gypsum). In addition, the desulfurized gypsum has a certain solidification effect on barium ions in barium slag, avoiding pollution to the fracturing application area, promoting the synergistic resource utilization and environmental protection of solid waste and hazardous waste. In the unconventional oil and gas resource extraction process, high-quality and low-cost fracturing proppant is an advantageous way to reduce costs and increase efficiency in resource development. Detailed Implementation

[0026] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0027] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0028] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0029] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be obvious to those skilled in the art. This application specification and embodiments are merely exemplary.

[0030] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0031] This invention provides a barium slag-containing fracturing proppant, comprising the following components by mass fraction:

[0032] The composition consists of 60-70% barium slag, 15-25% desulfurized gypsum, 0-15% quartz sand, and 1-7% bentonite, with the sum of the mass fractions of the above components being 100%.

[0033] In this invention, the barium slag-containing fracturing proppant comprises 60-70% barium slag, preferably 61-69%, more preferably 62-68%, even more preferably 63-66%, and even more preferably 64-65% by mass fraction.

[0034] In this invention, the specific surface area of ​​the barium slag is greater than or equal to 400 m². 2 / kg, for example, can be 410m 2 / kg, 430m 2 / kg, 450m 2 / kg, 460m 2 / kg, etc.

[0035] In this invention, the barium slag-containing fracturing proppant comprises 15-25% desulfurized gypsum, preferably 16-24%, more preferably 17-22%, even more preferably 18-21%, and even more preferably 19-20%.

[0036] The specific surface area of ​​the desulfurized gypsum is greater than or equal to 450 m². 2 / kg, for example, can be 460m 2 / kg, 470m2 / kg, 480m 2 / kg, 500m 2 / kg, etc.

[0037] In this invention, the main component of the desulfurized gypsum is similar to that of natural gypsum, namely calcium sulfate dihydrate CaSO4·2H2O. The soluble sulfate in the desulfurized gypsum can fix the soluble barium ions in the barium slag and generate insoluble barium sulfate precipitate through chemical reaction.

[0038] In this invention, the barium slag-containing fracturing proppant comprises 0-15% quartz sand, preferably 5-13%, more preferably 7-12%, and even more preferably 8-10%.

[0039] The specific surface area of ​​the quartz sand is greater than or equal to 400 m². 2 / kg, for example, can be 420m 2 / kg, 440m 2 / kg, 450m 2 / kg, 470m 2 / kg, etc.

[0040] In this invention, quartz sand serves to provide structural support.

[0041] In this invention, the barium slag-containing fracturing proppant comprises 1-7% bentonite, preferably 2-6%, more preferably 3-5%, and even more preferably 3.5-4%.

[0042] The specific surface area of ​​the bentonite is greater than or equal to 400 m². 2 / kg, for example, can be 410m 2 / kg, 420m 2 / kg, 440m 2 / kg, 470m 2 / kg, etc.

[0043] In this invention, bentonite is mainly added as a binder for the proppant. The amount added is small, which promotes the roundness, sphericity and strength of the fracturing proppant.

[0044] In this invention, barium slag, desulfurized gypsum, quartz sand and bentonite can be commercially available or made in-house, as long as they meet the chemical composition requirements.

[0045] In this invention, the chemical composition of the barium slag, by weight, includes: 30-40 parts SiO2, preferably 32-38 parts, more preferably 33-36 parts; 25-35 parts BaO, preferably 26-32 parts, more preferably 27-28 parts; 15-25 parts SO3, preferably 16-22 parts, more preferably 19-20 parts; 3-8 parts Fe2O3, preferably 4-7 parts, more preferably 5-6 parts; 1-4 parts Na2O, preferably 1.5-3 parts, more preferably 2-2.5 parts; 1-4 parts Al2O3, preferably 1.5-3 parts, more preferably 2-2.5 parts; 1-5 parts CaO, preferably 2-4 parts, more preferably 2.5-3 parts; 0-1 part K2O, preferably 0.2-0.8 parts, more preferably 0.4-0.6 parts; MgO 0-1 part, preferably 0.2-0.8 parts, even more preferably 0.4-0.6 parts; MnO 0-1 part, preferably 0.2-0.8 parts, even more preferably 0.4-0.6 parts; TiO2 0-1 part, preferably 0.2-0.8 parts, even more preferably 0.4-0.6 parts; P2O5 0-1 part, preferably 0.2-0.8 parts, even more preferably 0.4-0.6 parts.

[0046] In this invention, the chemical composition of the desulfurized gypsum, by weight, includes: CaO 40-55 parts, preferably 45-52 parts, more preferably 48-50 parts; SO3 40-50 parts, preferably 42-48 parts, more preferably 44-46 parts; MgO 0-2 parts, preferably 0.5-1.5 parts, more preferably 1-1.2 parts; SiO2 0-1.5 parts, preferably 0.2-0.8 parts, more preferably 0.4-0.6 parts; Al2O3 0-1 part, preferably 0.2-0.8 parts, more preferably 0.4-0.6 parts; Fe2O3 0-1 part, preferably 0.2-0.8 parts, more preferably 0.4-0.6 parts.

[0047] In this invention, the chemical composition of the quartz sand, by weight, includes: SiO2 95-99 parts, preferably 96-98 parts, more preferably 96.5-97 parts; Fe2O3 0-1 part, preferably 0.1-0.8 parts, more preferably 0.3-0.6 parts; CaO 0-1 part, preferably 0.2-0.8 parts, more preferably 0.4-0.6 parts; Al2O3 0-1 part, preferably 0.2-0.9 parts, more preferably 0.5-0.6 parts; MgO 1-2 parts, preferably 1.2-1.8 parts, more preferably 1.4-1.6 parts; TiO2 0-1 part, preferably 0.2-0.7 parts, more preferably 0.4-0.5 parts; ZrO2 0-1 part, preferably 0.3-0.8 parts, more preferably 0.4-0.5 parts; Na2O 0 to 1 part, preferably 0.4 to 0.8 parts, even more preferably 0.5 to 0.6 parts; K2O 0 to 1 part, preferably 0.2 to 0.8 parts, even more preferably 0.4 to 0.6 parts.

[0048] In this invention, the chemical composition of the bentonite, by weight, includes: 60-70 parts of SiO2, preferably 64-68 parts, more preferably 65-66 parts; 15-25 parts of Al2O3, preferably 18-24 parts, more preferably 20-22 parts; 1-5 parts of Na2O, preferably 2-4.5 parts, more preferably 3-4 parts; 1-2 parts of MgO, preferably 1.2-1.8 parts, more preferably 1.4-1.6 parts; 0-1 part of CaO, preferably 0.2-0.8 parts, more preferably 0.4-0.6 parts; and 1-2 parts of Fe2O3, preferably 1.3-1.8 parts, more preferably 1.5-1.6 parts.

[0049] In this invention, the chemical composition of barium slag, desulfurized gypsum, quartz sand, and bentonite refers to the content of various metal or mineral elements as oxides, and not to the content of compounds present as oxides in barium slag, desulfurized gypsum, quartz sand, or bentonite. Furthermore, the above chemical composition results can be obtained using conventional detection methods existing in the art, such as typical fluorescence detection methods after or without burn-off.

[0050] This invention also provides a method for preparing the above-mentioned barium slag-containing fracturing proppant, comprising the following steps:

[0051] Barium slag, desulfurized gypsum, quartz sand and bentonite are mixed and then successively ground, granulated and sintered to obtain a fracturing proppant containing barium slag.

[0052] The present invention does not specifically limit the mixing method, as long as the raw materials are mixed evenly. In the embodiments of the present invention, a step-by-step mixing method is adopted, specifically: first, barium slag and desulfurized gypsum are mixed evenly to obtain mixed micro powder; then, quartz sand and bentonite are added to the mixed micro powder and mixed evenly.

[0053] In this invention, to ensure that the material does not undergo localized reactions before use and thus affect its performance, the barium slag, desulfurized gypsum, quartz sand, and bentonite are mixed and dried. The moisture content after drying is 0.01-1%, preferably 0.05-0.8%, more preferably 0.1-0.6%, and even more preferably 0.2-0.4%.

[0054] In this invention, barium slag, desulfurized gypsum, quartz sand and bentonite are mixed and then ground. The particle size of the mixed raw materials after grinding is 500 to 1000 mesh, for example, 600 mesh, 700 mesh, 800 mesh, 900 mesh, etc.

[0055] In this invention, grinding increases the specific surface area of ​​the raw materials, which on the one hand stimulates the synergistic effect of barium slag and desulfurization gypsum, reducing the dissolution of free barium ions, and on the other hand improves the overall uniformity of the materials.

[0056] In this invention, the particle size of the pellet obtained by granulation is 20-70 mesh, preferably 25-65 mesh, more preferably 30-60 mesh, and even more preferably 40-50 mesh.

[0057] In this invention, the heating rate of the sintering is 6-10℃ / min, preferably 6.5-9℃ / min, more preferably 7-8℃ / min, the temperature is 1020-1100℃, preferably 1030-1090℃, more preferably 1040-1080℃, and even more preferably 1050-1060℃, and the holding time is 1-3h, preferably 1.5-2.5h, and more preferably 1.8-2h.

[0058] In this invention, sintering is carried out in an air atmosphere. After the sintering and heat preservation are completed, the billet is cooled to room temperature with the furnace to obtain a fracturing proppant containing barium slag.

[0059] When using the barium slag-containing fracturing proppant of the present invention, it is mixed with water at a water-cement ratio of 0.2 to 0.5:1. This water-cement ratio can be used to prepare fracturing proppant materials for oil well fracturing and the construction industry on a large scale.

[0060] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0061] In an embodiment of the present invention, the chemical composition of the barium slag, by weight, includes: 33 parts SiO2, 28 parts BaO, 19 parts SO3, 8 parts Fe2O, 3 parts Na2O, 33 parts Al2O3, 2 parts CaO, 1 part K2O, 1 part MgO, 1 part MnO, 1 part TiO2, and 1 part P2O5.

[0062] The chemical composition of the desulfurized gypsum, by weight, includes: 47 parts CaO, 44 parts SO3, 1 part MgO, 1.3 parts SiO2, 0.3 parts Al2O3, 0.4 parts Fe2O3, and 6 parts loss on ignition.

[0063] The chemical composition of the quartz sand, by weight, includes: 96 parts SiO2, 1 part Fe2O3, 1 part CaO, 1 part Al2O3, and 1 part MgO.

[0064] The chemical composition of the bentonite, by weight, includes: 66 parts SiO2, 19 parts Al2O3, 4 parts Na2O, 2 parts MgO, 1 part CaO, and 2 parts Fe2O3.

[0065] Example 1

[0066] The fracturing proppant containing barium slag is composed of the following components by mass fraction: 70% barium slag, 25% desulfurized gypsum, and 5% bentonite.

[0067] Among them, the specific surface area of ​​barium slag is 400 m². 2 / kg, the specific surface area of ​​desulfurized gypsum is 450m² 2 / kg, bentonite specific surface area is 400m² 2 / kg;

[0068] The preparation method of barium slag-containing fracturing proppant is as follows:

[0069] S1. Mix 70% barium slag and 25% desulfurized gypsum, and mix for 10 minutes to obtain mixed micro powder;

[0070] S2. Mix 5% bentonite with the mixed powder obtained in S1, dry it to a moisture content of 1% after mixing for 10 minutes, grind it for 80 minutes, and the average particle size of the mixture after grinding is 500 mesh. Continue granulation to obtain pellets with a particle size of 20 mesh.

[0071] S3. The spherical billet obtained in S2 is heated to 1080℃ in air at a heating rate of 5℃ / min, and held at this temperature for 2 hours. After the holding period, it is cooled to room temperature in the furnace to obtain a fracturing proppant containing barium slag.

[0072] Example 2

[0073] The fracturing proppant containing barium slag is composed of the following components by mass fraction: 70% barium slag, 20% desulfurized gypsum, 5% quartz sand, and 5% bentonite.

[0074] The specific surface area of ​​the barium slag is 400 m². 2 / kg, the specific surface area of ​​desulfurized gypsum is 450m². 2 / kg, the specific surface area of ​​quartz sand is 400m² 2 / kg, the specific surface area of ​​bentonite is 400m² 2 / kg;

[0075] The preparation method of barium slag-containing fracturing proppant is as follows:

[0076] S1. Mix 70% barium slag and 20% desulfurized gypsum, and mix for 10 minutes to obtain mixed micro powder;

[0077] S2. Mix 5% quartz sand, 5% bentonite and the mixed powder obtained in S1, mix for 10 min and dry to a moisture content of 1%, grind for 80 min. The average particle size of the mixture after grinding is 500 mesh. Continue granulation to obtain pellets with a particle size of 20 mesh.

[0078] S3. The spherical billet obtained in S2 is heated to 1100℃ in air at a heating rate of 8℃ / min, and held at this temperature for 1.5h. After the holding period, it is cooled to room temperature in the furnace to obtain a fracturing proppant containing barium slag.

[0079] Example 3

[0080] The only difference from Example 2 is that the barium slag-containing fracturing proppant is composed of the following components by mass fraction: 70% barium slag, 15% desulfurized gypsum, 10% quartz sand, and 5% bentonite.

[0081] The preparation method of the barium slag-containing fracturing proppant is the same as in Example 2.

[0082] Example 4

[0083] The only difference from Example 2 is that the barium slag-containing fracturing proppant is composed of the following components by mass fraction: 65% barium slag, 15% desulfurized gypsum, 15% quartz sand, and 5% bentonite.

[0084] The preparation method of the barium slag-containing fracturing proppant is the same as in Example 2.

[0085] Example 5

[0086] The only difference from Example 2 is that the barium slag-containing fracturing proppant is composed of the following components by mass fraction: 66% barium slag, 24% desulfurized gypsum, 7% quartz sand, and 3% bentonite.

[0087] The preparation method of the barium slag-containing fracturing proppant is the same as in Example 2.

[0088] Example 6

[0089] The only difference from Example 2 is that the barium slag-containing fracturing proppant is composed of the following components by mass fraction: 70% barium slag, 20% desulfurized gypsum, 7% quartz sand, and 3% bentonite.

[0090] The preparation method of the barium slag-containing fracturing proppant is the same as in Example 2.

[0091] Example 7

[0092] The only difference from Example 2 is that the barium slag-containing fracturing proppant is composed of the following components by mass fraction: 60% barium slag, 20% desulfurized gypsum, 15% quartz sand, and 5% bentonite.

[0093] The preparation method of the barium slag-containing fracturing proppant is the same as in Example 2.

[0094] Example 8

[0095] The only difference from Example 2 is that the barium slag-containing fracturing proppant is composed of the following components by mass fraction: 64% barium slag, 16% desulfurized gypsum, 13% quartz sand, and 7% bentonite.

[0096] The preparation method of the barium slag-containing fracturing proppant is the same as in Example 2.

[0097] Example 9

[0098] The only difference from Example 2 is that the barium slag-containing fracturing proppant is composed of the following components by mass fraction: 65% barium slag, 20% desulfurized gypsum, 12% quartz sand, and 3% bentonite.

[0099] The preparation method of the barium slag-containing fracturing proppant is the same as in Example 2.

[0100] Example 10

[0101] The only difference from Example 2 is that the barium slag-containing fracturing proppant is composed of the following components by mass fraction: 68% barium slag, 17% desulfurized gypsum, 10% quartz sand, and 5% bentonite.

[0102] The preparation method of the barium slag-containing fracturing proppant is the same as in Example 2.

[0103] Example 11

[0104] The only difference from Example 2 is that the barium slag-containing fracturing proppant is composed of the following components by mass fraction: 69% barium slag, 21% desulfurized gypsum, 5% quartz sand, and 5% bentonite.

[0105] The preparation method of the barium slag-containing fracturing proppant is the same as in Example 2.

[0106] Example 12

[0107] The only difference from Example 2 is that the barium slag-containing fracturing proppant is composed of the following components by mass fraction: 60% barium slag, 25% desulfurized gypsum, 12% quartz sand, and 3% bentonite.

[0108] The preparation method of the barium slag-containing fracturing proppant is the same as in Example 2.

[0109] Example 13

[0110] The only difference from Example 2 is that the barium slag-containing fracturing proppant is composed of the following components by mass fraction: 62% barium slag, 20% desulfurized gypsum, 13% quartz sand, and 5% bentonite.

[0111] The preparation method of the barium slag-containing fracturing proppant is the same as in Example 2.

[0112] Example 14

[0113] The only difference from Example 2 is that the barium slag-containing fracturing proppant is composed of the following components by mass fraction: 70% barium slag, 15% desulfurized gypsum, 12% quartz sand, and 3% bentonite.

[0114] The preparation method of the barium slag-containing fracturing proppant is the same as in Example 2.

[0115] Example 15

[0116] The only difference from Example 2 is that the barium slag-containing fracturing proppant is composed of the following components by mass fraction: 60% barium slag, 20% desulfurized gypsum, 15% quartz sand, and 5% bentonite.

[0117] The preparation method of the barium slag-containing fracturing proppant is the same as in Example 2.

[0118] Comparative Example 1

[0119] The only difference from Example 2 is that the barium slag-containing fracturing proppant is composed of the following components by mass fraction: 70% barium slag, 20% desulfurized gypsum, 10% quartz sand, and 0% bentonite.

[0120] The preparation method of the barium slag-containing fracturing proppant is the same as in Example 2.

[0121] The leaching concentration of Ba in the barium slag selected in the examples and comparative examples was tested according to the national standard (HJ / T 557—2010) "Solid Waste Leaching Toxicity Method - Horizontal Vibration Method".

[0122] According to SYT5108-2014 "Test Method for Proppant Performance", the fracturing proppant of the present invention was sampled and its bulk density, apparent density, and breakage rate were measured. The fracturing proppant of the present invention was leached according to GB5085.3-2007 "Identification Standard for Hazardous Waste - Leaching Toxicity Identification", GB5749-2006 "Standards for Drinking Water Quality" and HJ557-2010 "Leaching Toxicity of Solid Waste - Leaching Method - Horizontal Shaking Method", and the leachate was tested. The performance test results are shown in Table 1.

[0123] Table 1 Performance Test Results

[0124]

[0125]

[0126] As shown in Examples 1-15 of Table 1, the fracturing proppant containing barium slag provided by this invention, after sintering, exhibits a breakage rate below the limit of 9% under a closure pressure of 52 MPa. This indicates that the fracturing proppant of this invention has strong anti-breakage ability and high stability and durability in oil well fracturing operations. The results also show that increasing the barium slag content leads to a certain degree of reduction in the mechanical properties of the proppant. Therefore, in practical applications, appropriate material ratios and sintering parameters should be selected by comprehensively considering factors such as the consumption capacity of barium slag powder and the required strength for oil well fracturing to meet actual fracturing proppant needs.

[0127] As can be seen from Examples 7-9 and 12-14 in Table 1, when the amount of quartz sand powder is too large or the specific surface area of ​​the powder is large, the mechanical properties of the fracturing material will be improved to a small extent. However, Example 7 requires a reduction in the amount of barium slag, which leads to slow consumption of barium slag and increased cost.

[0128] As can be seen from the comparison between Example 6 and Comparative Example 1 in Table 1, the proppant prepared using bentonite as raw material has a breakage rate of less than 9% under a closure pressure of 52 MPa. Bentonite is one of the necessary raw materials for preparing fracturing proppant. It can be seen that the barium slag-based fracturing proppant prepared by the method of the present invention has good mechanical properties and meets national standards.

[0129] As can be seen from the comparison of Examples 1-15 in Table 1, the higher the content of desulfurized gypsum, the lower the leaching concentration of barium ions, and the better the solidification effect of barium ions. Therefore, to prepare a barium slag-based fracturing proppant, the ratio of barium slag to desulfurized gypsum needs to be within the above-mentioned content range. This ensures that the barium ion leaching concentration of the prepared fracturing proppant meets the standards for drinking water, achieving the synergistic resource utilization of hazardous and solid waste. The barium slag-containing fracturing proppant of this invention enables the harmless and resource-based utilization of various industrial solid wastes and hazardous wastes, providing a high-performance proppant with advantages of good performance and low cost.

[0130] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A fracturing proppant containing barium slag, characterized in that, Components including the following mass fractions: The composition consists of 60-70% barium slag, 15-25% desulfurized gypsum, 0-15% quartz sand, and 1-7% bentonite, with the sum of the mass fractions of the above components being 100%. The chemical composition of the barium slag, by weight, includes: 30-40 parts SiO2, 25-35 parts BaO, 15-25 parts SO3, 3-8 parts Fe2O3, 1-4 parts Na2O, 1-4 parts Al2O3, 1-5 parts CaO, 0-1 parts K2O, 0-1 parts MgO, 0-1 parts MnO, 0-1 parts TiO2, and 0-1 parts P2O5. The specific surface area of ​​the barium slag is greater than or equal to 400 m². 2 / kg; The chemical composition of the desulfurized gypsum, by weight, includes: CaO 40-55 parts, SO3 40-50 parts, MgO 0-2 parts, SiO2 0-1.5 parts, Al2O3 0-1 parts, and Fe2O3 0-1 parts. The specific surface area of ​​the desulfurized gypsum is greater than or equal to 450 m². 2 / kg; The method for preparing the barium-containing fracturing proppant is characterized by comprising the following steps: The barium slag, desulfurized gypsum, quartz sand and bentonite are mixed and then successively ground, granulated and sintered to obtain the fracturing proppant containing barium slag. The particle size of the mixture of ground barium slag, desulfurized gypsum, quartz sand and bentonite is 500-1000 mesh.

2. The fracturing proppant containing barium slag according to claim 1, characterized in that, The chemical composition of the quartz sand, by weight, includes: 95-99 parts SiO2, 0-1 parts Fe2O3, 0-1 parts CaO, 0-1 parts Al2O3, 1-2 parts MgO, 0-1 parts TiO2, 0-1 parts ZrO2, 0-1 parts Na2O, and 0-1 parts K2O. The specific surface area of ​​the quartz sand is greater than or equal to 400 m². 2 / kg.

3. The fracturing proppant containing barium slag according to claim 2, characterized in that, The chemical composition of the bentonite, by weight, includes: 60-70 parts SiO2, 15-25 parts Al2O3, 1-5 parts Na2O, 1-2 parts MgO, 0-1 parts CaO, and 1-2 parts Fe2O3. The specific surface area of ​​the bentonite is greater than or equal to 400 m². 2 / kg.

4. A method for preparing a barium-containing fracturing proppant according to any one of claims 1 to 3, characterized in that, Includes the following steps: The barium slag, desulfurized gypsum, quartz sand and bentonite are mixed and then successively ground, granulated and sintered to obtain the fracturing proppant containing barium slag.

5. The preparation method according to claim 4, characterized in that, The particle size of the mixture of ground barium slag, desulfurized gypsum, quartz sand and bentonite is 500-1000 mesh.

6. The preparation method according to claim 5, characterized in that, The particle size of the pellets obtained by granulation is 20-70 mesh.

7. The preparation method according to claim 4, characterized in that, The sintering process involves a heating rate of 6–10 °C / min, a temperature of 1020–1100 °C, and a holding time of 1–3 h.

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