Fracturing propping agent containing barium slag and preparation method thereof

Abstract

The invention relates to the technical field of petroleum and natural gas deep well mining and building materials, in particular to a fracturing propping agent containing barium slag and a preparation method of the fracturing propping agent. The fracturing propping agent containing the barium slag comprises the following components in percentage by mass: 60-70% of the barium slag, 15-25% of desulfurized gypsum, 0-15% of quartz sand and 1-7% of bentonite, wherein the sum of the mass fractions of the components is 100%. According to the fracturing propping agent, the better mixing amount of the barium slag and the desulfurized gypsum in a low-aluminum system is provided, the raw material composition of the fracturing propping agent containing the barium slag and the desulfurized gypsum is simplified, the performance of the fracturing propping agent is improved to a greater extent, the fracturing propping agent is simple in composition, the preparation method is simple and convenient, and the industrial application cost is reduced. Meanwhile, the leaching concentration of heavy metal ions in the fracturing propping agent system is all lower than the drinking water standard, so that the harmless and recycling problems of industrial hazardous waste and industrial solid waste can be solved, and synergistic resource utilization and environmental protection of the solid waste and the hazardous waste are promoted.

Description

Technical Field

[0001] The invention relates to the technical field of deep well exploitation of petroleum and natural gas and building materials, and in particular to a fracturing proppant containing barium slag and a preparation method thereof. Background Art

[0002] Barium slag is a byproduct of the barite refining process, especially the carbon thermal reduction process of barite, in which about 0.8 to 1.0 tons of barium slag are produced for every ton of barite. Barium slag mainly contains acid-soluble barium and water-soluble barium, with a high content of barium ions and toxicity, and is classified as HW47 hazardous waste. At present, storage and landfill are the main methods for treating barium slag. Storage not only occupies a large amount of land resources, but also pollutes the environment, especially at high temperatures, it is easy to spontaneously combust and release toxic gases. After rainwater infiltration, a large amount of yellow wastewater containing sulfide is produced, which flows into surface water and groundwater, polluting the water body, and the barium sulfide and acid-soluble barium in the waste slag also have a toxic effect on the soil. The existing technology for the comprehensive utilization of barium slag is mainly concentrated in the fields of building materials and chemical products, but the current technical process is complicated, and the actual consumption of barium slag is limited. Therefore, it is urgent to develop and implement innovative technologies to effectively reduce the environmental pollution caused by the storage of barium slag.

[0003] Fracturing proppant is a material widely used in the process of oil field exploitation. It is mainly used for supporting operations underground in oil fields to increase the production of oil and natural gas. The main raw materials of fracturing proppants include high-quality bauxite, high aluminum, high silicon raw materials, etc., but these raw materials have small reserves and high prices, which makes the cost of fracturing proppants remain high. The use of waste barium slag to prepare ultra-low-cost fracturing proppants can not only solve the problem of harmlessness and resource utilization of industrial hazardous waste (barium slag), promote the coordinated resource utilization of solid waste and hazardous waste and environmental protection, but also provide ultra-low-cost fracturing proppants for hydraulic fracturing, laying the foundation for engineering applications. However, the existing barium slag fracturing proppants have the following problems: the high proportion of barium slag added to prepare fracturing proppants has not been achieved. Summary of the invention

[0004] The object of the present invention is to provide a fracturing proppant containing barium slag and a preparation method thereof, so as to achieve harmless treatment and resource utilization of the barium slag.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a fracturing proppant containing barium slag, comprising the following components in mass fractions:

[0007] Barium slag 60-70%, desulfurized gypsum 15-25%, quartz sand 0-15%, bentonite 1-7%, the sum of the mass fractions of the above components is 100%.

[0008] Optionally, the chemical composition of the barium slag includes, by weight: 30-40 parts of SiO2, 5-35 parts of BaO2, 15-25 parts of SO3, 3-8 parts of Fe2O, 1-4 parts of Na2O, 1-4 parts of Al2O3, 1-5 parts of CaO, 0-1 part of K2O, 0-1 part of MgO, 0-1 part of MnO, 0-1 part of TiO2, and 50-1 part of P2O;

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

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

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

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

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

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

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

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

[0017] The barium slag, desulfurized gypsum, quartz sand and bentonite are mixed and then ground, granulated and sintered in sequence 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 500-1000 meshes.

[0019] Optionally, the particle size of the ball blank obtained by granulation is 20 to 70 meshes.

[0020] Optionally, the sintering temperature rise rate is 6 to 10° C. / min, the temperature is 1020 to 1100° C., and the insulation time is 1 to 3 hours.

[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 utilizes barium slag to replace traditional high-aluminum and high-silicon raw materials, utilizes desulfurized gypsum to fully solidify free barium, and synergistically utilizes desulfurized gypsum, quartz sand and bentonite to prepare the ultra-low-cost fracturing proppant, so that the barium slag and desulfurized gypsum are utilized as resources to the maximum extent, the raw material cost is greatly reduced, and the utilization rate of the barium slag is higher.

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

[0024] (3) The present invention provides an optimal dosage of barium slag and desulfurized gypsum in a low aluminum system, simplifies the raw material composition of the fracturing proppant containing barium slag and desulfurized gypsum, and improves the performance of the 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 the present invention is all lower than the drinking water standard, thereby being able to solve the problem of harmlessness and resource utilization of industrial hazardous waste (barium slag) and industrial solid waste (desulfurized gypsum). In addition, desulfurized gypsum has a certain solidification effect on the barium ions in the barium slag, avoiding pollution to the fracturing application area, promoting the coordinated resource utilization of solid waste and hazardous waste and environmental protection. In the process of unconventional oil and gas resource exploitation, high-quality and low-cost fracturing proppants are a favorable way to achieve cost reduction and efficiency improvement in resource development. DETAILED DESCRIPTION

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

[0027] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0028] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0029] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present application description and examples are exemplary only.

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

[0031] The present invention provides a fracturing proppant containing barium slag, comprising the following components in mass fractions:

[0032] Barium slag 60-70%, desulfurized gypsum 15-25%, quartz sand 0-15%, bentonite 1-7%, the sum of the mass fractions of the above components is 100%.

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

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

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

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

[0037] In the present invention, the main component of the desulfurized gypsum is similar to 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 to generate insoluble barium sulfate precipitate through chemical reaction.

[0038] In the present invention, the fracturing proppant containing barium slag includes 0-15% of 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 400m 2 / kg, for example, 420m 2 / kg, 440m 2 / kg, 450m 2 / kg, 470m 2 / kg, etc.

[0040] In the present invention, the quartz sand plays a role of supporting strength.

[0041] In the present invention, the fracturing proppant containing barium slag includes 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 400m 2 / kg, for example, 410m 2 / kg, 420m 2 / kg, 440m 2 / kg, 470m 2 / kg, etc.

[0043] In the present invention, bentonite is mainly added as a bonding material of the proppant in a relatively small amount, and plays a role in promoting the roundness, sphericity and strength of the fracturing proppant.

[0044] In the present invention, the barium slag, desulfurized gypsum, quartz sand and bentonite can be purchased from the market or made at home, as long as the chemical composition requirements are met.

[0045] In the present invention, the chemical composition of the barium slag includes, by weight: 30-40 parts of SiO2, preferably 32-38 parts, and more preferably 33-36 parts; 25-35 parts of BaO, preferably 26-32 parts, and more preferably 27-28 parts; 15-25 parts of SO3, preferably 16-22 parts, and more preferably 19-20 parts; 3-8 parts of Fe2O, preferably 4-7 parts, and more preferably 5-6 parts; 1-4 parts of Na2O, preferably 1.5-3 parts, and more preferably 2-2.5 parts; 1-4 parts of Al2O3, preferably 1.5-3 parts, and more preferably 2-2.5 parts; 1-5 parts of CaO, preferably 2-4 parts, and more preferably 2.5-3 parts; 0-1 parts of K2O, preferably 0.2-0.8 parts, and more preferably 0.4-0.6 parts; and 1-2 parts of MgO. 0 to 1 part, preferably 0.2 to 0.8 part, more preferably 0.4 to 0.6 part; MnO 0 to 1 part, preferably 0.2 to 0.8 part, more preferably 0.4 to 0.6 part; TiO2 0 to 1 part, preferably 0.2 to 0.8, more preferably 0.4 to 0.6 part; P2O5 0 to 1 part, preferably 0.2 to 0.8 part, more preferably 0.4 to 0.6 part.

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

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

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

[0049] In the present invention, the chemical composition of the barium slag, desulfurized gypsum, quartz sand and bentonite refers to the content of various metals or mineral elements in the form of oxides, and does not refer to the content of compounds existing in the form of oxides in the barium slag, desulfurized gypsum, quartz sand or bentonite. In addition, the above chemical composition results can be obtained by conventional detection methods available in the art, such as typical fluorescence detection methods after or before burnout.

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

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

[0052] The present invention has no special limitation on the mixing method, as long as the raw materials can be mixed evenly. In the embodiment of the present invention, the mixing is carried out in a step-by-step mixing method, specifically: firstly, the barium slag and the desulfurized gypsum are mixed evenly to obtain a mixed fine powder; then, quartz sand and bentonite are added to the mixed fine powder and mixed evenly.

[0053] In the present invention, in order to ensure that the material does not undergo local reaction before use and affect the use effect, the present invention mixes barium slag, desulfurized gypsum, quartz sand and bentonite and then dries them. The moisture content after drying is 0.01-1%, preferably 0.05-0.8%, further preferably 0.1-0.6%, and further preferably 0.2-0.4%.

[0054] In the present 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 500-1000 mesh, for example, 600 mesh, 700 mesh, 800 mesh, 900 mesh, etc.

[0055] In the present invention, the specific surface area of ​​the raw material is increased by grinding, which, on the one hand, stimulates the synergistic effect of barium slag and desulfurized gypsum to reduce the dissolution of free barium ions, and on the other hand, improves the overall uniformity of the material.

[0056] In the present invention, the particle size of the pellets obtained by granulation is 20 to 70 meshes, preferably 25 to 65 meshes, more preferably 30 to 60 meshes, and further preferably 40 to 50 meshes.

[0057] In the present invention, the sintering heating rate is 6 to 10°C / min, preferably 6.5 to 9°C / min, and further preferably 7 to 8°C / min, the temperature is 1020 to 1100°C, preferably 1030 to 1090°C, further preferably 1040 to 1080°C, and further preferably 1050 to 1060°C, and the holding time is 1 to 3h, preferably 1.5 to 2.5h, and further preferably 1.8 to 2h.

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

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

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

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

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

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

[0064] The chemical composition of the bentonite, by weight, includes: 66 parts of SiO2, 19 parts of Al2O3, 4 parts of Na2O, 2 parts of MgO, 1 part of CaO, and 2 parts of 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 400m 2 / kg, the specific surface area of ​​desulfurized gypsum is 450m 2 / kg, the specific surface area of ​​bentonite is 400m 2 / kg;

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

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

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

[0071] S3. The pellet obtained in S2 is heated to 1080°C at a heating rate of 5°C / min under air atmosphere, and kept at this temperature for 2 hours. After the heat preservation, it is cooled to room temperature with 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 in mass fractions: 70% of barium slag, 20% of desulfurized gypsum, 5% of quartz sand, and 5% of bentonite;

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

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

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

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

[0078] S3. The pellet obtained in S2 is heated to 1100°C at a heating rate of 8°C / min under air atmosphere, and kept at this temperature for 1.5 hours. After the end of the heat preservation, it is cooled to room temperature with the furnace to obtain a fracturing proppant containing barium slag.

[0079] Example 3

[0080] The only difference from Example 2 is that the fracturing proppant containing barium slag 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 fracturing proppant containing barium slag is the same as that in Example 2.

[0082] Example 4

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

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

[0085] Example 5

[0086] The only difference from Example 2 is that the fracturing proppant containing barium slag 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 fracturing proppant containing barium slag is the same as that in Example 2.

[0088] Example 6

[0089] The only difference from Example 2 is that the fracturing proppant containing barium slag 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 fracturing proppant containing barium slag is the same as that in Example 2.

[0091] Example 7

[0092] The only difference from Example 2 is that the fracturing proppant containing barium slag 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 fracturing proppant containing barium slag is the same as that in Example 2.

[0094] Example 8

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

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

[0097] Example 9

[0098] The only difference from Example 2 is that the fracturing proppant containing barium slag 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 fracturing proppant containing barium slag is the same as that in Example 2.

[0100] Example 10

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

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

[0103] Embodiment 11

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

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

[0106] Example 12

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

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

[0109] Embodiment 13

[0110] The only difference from Example 2 is that the fracturing proppant containing barium slag 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 fracturing proppant containing barium slag is the same as that in Example 2.

[0112] Embodiment 14

[0113] The only difference from Example 2 is that the fracturing proppant containing barium slag 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 fracturing proppant containing barium slag is the same as that in Example 2.

[0115] Embodiment 15

[0116] The only difference from Example 2 is that the fracturing proppant containing barium slag 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 fracturing proppant containing barium slag is the same as that in Example 2.

[0118] Comparative Example 1

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

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

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

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

[0123] Table 1 Performance test results

[0124]

[0125]

[0126] As shown in Examples 1 to 15 in Table 1, the fracturing proppant containing barium slag provided by the present invention, after sintering, can have a crushing rate lower than the limit requirement of 9% at a closing pressure of 52MPa, indicating that the fracturing proppant of the present invention has strong anti-crushing ability and strong stability and durability in oil well fracturing operations. As can be seen from the results, when the dosage of barium slag is increased, the mechanical properties of the proppant will be reduced to a certain extent. Therefore, in actual use, the consumption capacity of barium slag micropowder, the required strength requirements of oil well fracturing and other issues should be comprehensively considered to select appropriate material ratios and sintering parameters to meet the actual fracturing agent needs.

[0127] It can be seen from Examples 7 to 9 and 12 to 14 in Table 1 that 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, but Example 7 needs to reduce the amount of barium slag, resulting in slow consumption of the barium slag and increased costs.

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

[0129] From the comparison of Examples 1 to 15 in Table 1, it can be seen that the greater the amount of desulfurized gypsum added, the lower the leaching concentration of barium ions is generally, and the better the solidification effect of barium ions is. It can be seen that if a barium slag-based fracturing proppant is to be prepared, the ratio of barium slag to desulfurized gypsum needs to be within the above content range, so that the barium ion leaching concentration of the prepared fracturing proppant can meet the drinking water standard and realize the coordinated resource utilization of hazardous waste and solid waste. The fracturing proppant containing barium slag of the present invention enables a variety of industrial solid wastes and hazardous wastes to be harmless and resource-utilized, and provides a proppant with excellent performance, which has the advantages of good performance and low cost.

[0130] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A fracturing proppant containing barium slag, characterized in that: The following components are included in mass fraction: Barium slag 60-70%, desulfurized gypsum 15-25%, quartz sand 0-15%, bentonite 1-7%, the sum of the mass fractions of the above components is 100%.

2. The fracturing proppant containing barium slag according to claim 1, characterized in that: The chemical composition of the barium slag includes, by weight, 30-40 parts of SiO2, 25-35 parts of BaO, 15-25 parts of SO3, 3-8 parts of Fe2O, 1-4 parts of Na2O, 1-4 parts of Al2O3, 1-5 parts of CaO, 0-1 parts of K2O, 0-1 parts of MgO, 0-1 parts of MnO, 0-1 parts of TiO2, and 50-1 parts of P2O; The specific surface area of ​​the barium slag is greater than or equal to 400m 2 / kg.

3. The fracturing proppant containing barium slag according to claim 2, characterized in that: The chemical composition of the desulfurized gypsum includes, by weight: 40-55 parts of CaO, 40-50 parts of SO3, 0-2 parts of MgO, 0-1.5 parts of SiO2, 0-1 parts of Al2O3, and 0-1 parts of Fe2O3; The specific surface area of ​​the desulfurized gypsum is greater than or equal to 450m 2 / kg.

4. The fracturing proppant containing barium slag according to any one of claims 1 to 3, characterized in that: The chemical composition of the quartz sand is calculated by weight, including: SiO2 95-99 parts, Fe2O3 0-1 part, CaO 0-1 part, Al2O3 0-1 part, MgO 1-2 parts, TiO2 0-1 part, ZrO2 0-1 part, Na2O 0-1 part, K2O 0-1 part; The specific surface area of ​​the quartz sand is greater than or equal to 400m 2 / kg.

5. The fracturing proppant containing barium slag according to claim 4, characterized in that: The chemical composition of the bentonite includes, by weight, 60-70 parts of SiO2, 15-25 parts of Al2O3, 1-5 parts of Na2O, 1-2 parts of MgO, 0-1 parts of CaO, and 1-2 parts of Fe2O3; The specific surface area of ​​the bentonite is greater than or equal to 400m 2 / kg.

6. A method for preparing a fracturing proppant containing barium slag according to any one of claims 1 to 5, characterized in that: The following steps are involved: The barium slag, desulfurized gypsum, quartz sand and bentonite are mixed and then ground, granulated and sintered in sequence to obtain the fracturing proppant containing barium slag.

7. The preparation method according to claim 6, characterized in that: The particle size of the mixture of barium slag, desulfurized gypsum, quartz sand and bentonite after grinding is 500-1000 meshes.

8. The preparation method according to claim 7, characterized in that: The particle size of the pellets obtained by the granulation is 20 to 70 meshes.

9. The preparation method according to claim 6, characterized in that: The sintering temperature rise rate is 6-10°C / min, the temperature is 1020-1100°C, and the heat preservation time is 1-3h.

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