A plugging gelatinizing agent for coal mine and a preparation method thereof

Abstract

The application relates to a coal mine plugging gelatinizing agent and a preparation method thereof, and relates to the technical field of coal mine plugging materials. The coal mine plugging gelatinizing agent comprises the following components in parts by weight: modified bentonite 60-75 parts, calcium chloride 10-25 parts, a filler 1-10 parts and cellulose 0.5-5 parts. The modified bentonite is obtained by mixing and magnetizing modification of bentonite and sodium silicate; and the filler is composed of spherical aluminum powder and hydrotalcite powder. The modified bentonite prepared by mixing and magnetizing modification of bentonite and sodium silicate is used as the main component, so that the compressive strength of the gelatinizing system is improved, and the overall adhesion is strengthened; in combination with the filler composed of spherical aluminum powder and hydrotalcite powder, calcium chloride and cellulose, the viscoelasticity, compactness and piling property of the mud can be effectively improved, so that the problems of poor compressive strength and poor air plugging effect of the existing inorganic plugging gelatinizing agent are effectively solved.

Description

Technical Field

[0001] This application relates to the field of coal mine sealing materials technology, and in particular to a sealing gelling agent for coal mines and its preparation method. Background Technology

[0002] In the field of coal mine fire zone sealing and goaf plugging technology, fire prevention and extinguishing filling materials are commonly used. The main process includes: making materials such as loess and fly ash into liquid mud and then using a gel to solidify the mud, forming a filling and sealing material that provides support and protection functions such as fire prevention and waterproofing.

[0003] Currently, compared to conventional two-component high-water-content gelling agents, inorganic gelling agents are characterized by low cost and minimal environmental impact, making them more widely used in underground coal mine operations. However, existing inorganic sealing gelling agents suffer from poor compressive strength and ineffective air-sealing properties, thus limiting their further application. Summary of the Invention

[0004] This application provides a sealing gelling agent for coal mines and its preparation method to solve the technical problems of poor compressive strength and poor air-stopping effect of existing inorganic sealing gelling agents.

[0005] In a first aspect, this application provides a sealing gelling agent for coal mines, which, by weight, comprises the following components:

[0006] 60-75 parts modified bentonite, 10-25 parts calcium chloride, 1-10 parts filler and 0.5-5 parts cellulose;

[0007] The modified bentonite is obtained by magnetizing and modifying a mixture of bentonite and sodium silicate; the filler is composed of spherical aluminum powder and hydrotalcite powder.

[0008] Furthermore, the weight ratio of the bentonite to the sodium silicate is (5-7):(1-2).

[0009] Furthermore, the preparation method of the modified bentonite includes the following steps:

[0010] The bentonite and sodium silicate are added to water for a first mixing to obtain a slurry;

[0011] The slurry was placed in a rotating magnetic field for magnetization modification, and then dried and ground to obtain the modified bentonite.

[0012] The working parameters for the magnetization modification include: a rotational speed of 1000–1100 rpm, a magnetic field strength of 0.04–0.06 T, and a magnetization time of 20–40 min.

[0013] Furthermore, the modified bentonite has a particle size of 2–5 mm.

[0014] Furthermore, the modified bentonite accounts for 0.6 to 0.8% of the total weight of the coal mine sealing gelling agent.

[0015] Furthermore, the weight ratio of the spherical aluminum powder to the hydrotalcite powder is (20-25):(1-2).

[0016] Furthermore, the particle size of the spherical aluminum powder is 200-300 mesh.

[0017] Furthermore, the particle size of the hydrotalcite powder is 100-200 mesh.

[0018] Secondly, this application provides a method for preparing the sealing gelling agent for coal mines as described in any one of the first aspects, the preparation method comprising:

[0019] The modified bentonite was obtained;

[0020] The modified bentonite, calcium chloride, filler and cellulose are added to water for a second mixing to obtain the sealing gelling agent for coal mines.

[0021] Furthermore, the weight of the added water is 4 to 8 times the total weight of all raw materials of the coal mine sealing gelling agent.

[0022] The technical solutions provided in this application have at least the following advantages compared with the prior art:

[0023] This application provides a sealing gelling agent for coal mines. The sealing gelling agent uses modified bentonite, which is prepared by magnetic modification of bentonite and sodium silicate, as the main component. This not only improves the compressive strength of the gelling system, but also strengthens the overall adhesion. When used in combination with fillers composed of spherical aluminum powder and hydrotalcite powder, calcium chloride, and cellulose, it can effectively improve the viscoelasticity, density, and stacking properties of the mud, thereby effectively solving the problems of poor compressive strength and poor air-stopping effect of existing inorganic sealing gelling agents. Attached Figure Description

[0024] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0025] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic flowchart illustrating a method for preparing a sealing gelling agent for coal mines, as provided in an embodiment of this application. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

[0029] In a first aspect, this application provides a sealing gelling agent for coal mines, which, by weight, comprises the following components:

[0030] 60-75 parts modified bentonite, 10-25 parts calcium chloride, 1-10 parts filler and 0.5-5 parts cellulose;

[0031] The modified bentonite is obtained by magnetizing and modifying a mixture of bentonite and sodium silicate; the filler is composed of spherical aluminum powder and hydrotalcite powder.

[0032] This application provides a sealing gelling agent for coal mines. The sealing gelling agent uses modified bentonite, which is prepared by magnetic modification of bentonite and sodium silicate, as the main component. This not only improves the compressive strength of the gelling system, but also strengthens the overall adhesion. When used in combination with fillers composed of spherical aluminum powder and hydrotalcite powder, calcium chloride, and cellulose, it can effectively improve the viscoelasticity, density, and stacking properties of the mud, thereby effectively solving the problems of poor compressive strength and poor air-stopping effect of existing inorganic sealing gelling agents.

[0033] In some specific embodiments, the modified bentonite may be present in weight parts of 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, and 75, etc.

[0034] In some specific embodiments, the weight parts of the calcium chloride may be 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, etc.

[0035] In some specific embodiments, the weight parts of the filler may be 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, etc.

[0036] In some specific embodiments, the weight parts of the cellulose may be 0.5 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, and 5 parts, etc.

[0037] Preferably, the sealing gelling agent for coal mines comprises the following components by weight: 65-70 parts modified bentonite, 15-20 parts calcium chloride, 5-7 parts filler, and 2-4 parts cellulose.

[0038] More preferably, the sealing gelling agent for coal mines comprises the following components by weight: 67.5 parts modified bentonite, 16 parts calcium chloride, 6 parts filler, and 3 parts cellulose.

[0039] In one embodiment of this application, the weight ratio of the bentonite to the sodium silicate is (5-7):(1-2).

[0040] Preferably, the modified bentonite obtained by magnetization modification using a mixture of bentonite and sodium silicate in a weight ratio of (5-7):(1-2) exhibits better performance. In some specific embodiments, the weight ratio of the bentonite to the sodium silicate can be 5:1, 5:2, 7:1, 7:2, etc.

[0041] As one embodiment of this application, the method for preparing the modified bentonite includes the following steps:

[0042] The bentonite and sodium silicate are added to water for a first mixing to obtain a slurry;

[0043] The slurry was placed in a rotating magnetic field for magnetization modification, and then dried and ground to obtain the modified bentonite.

[0044] The working parameters for the magnetization modification include: a rotational speed of 1000–1100 rpm, a magnetic field strength of 0.04–0.06 T, and a magnetization time of 20–40 min.

[0045] The magnetization modification preparation process of the modified bentonite of this application can be carried out using existing equipment, such as a rotating magnetic field generator or a rotating magnetic field instrument, by adjusting the corresponding parameters of the device. In some specific embodiments, the magnetization time can be 20 min, 21 min, 22 min, 23 min, 24 min, 25 min, 26 min, 27 min, 28 min, 29 min, 30 min, 31 min, 32 min, 33 min, 34 min, 35 min, 36 min, 37 min, 38 min, 39 min, 40 min, etc.

[0046] In one embodiment of this application, the modified bentonite has a particle size of 2-5 mm.

[0047] Preferably, the modified bentonite has a particle size of 2-5 mm. In some specific embodiments, the modified bentonite with a particle size of 2-5 mm can be obtained by sieving the dried and ground modified bentonite.

[0048] In one embodiment of this application, the modified bentonite accounts for 0.6 to 0.8% of the total weight of the coal mine sealing gelling agent.

[0049] This application controls the weight of the modified bentonite to be 0.6-0.8% of the total weight of the coal mine sealing gelling agent, which can significantly improve the compressive strength and air-blocking effect of existing inorganic sealing gelling agents. Preferably, the weight of the modified bentonite accounts for 0.73% of the total weight of the coal mine sealing gelling agent.

[0050] In one embodiment of this application, the weight ratio of the spherical aluminum powder to the hydrotalcite powder is (20-25):(1-2).

[0051] In some specific embodiments, preferably, the weight ratio of the spherical aluminum powder to the hydrotalcite powder is 23:2.

[0052] In one embodiment of this application, the particle size of the spherical aluminum powder is 200-300 mesh.

[0053] Preferably, spherical aluminum powder with a particle size of 200-300 mesh is selected, which makes the slurry more compact and has better stacking properties.

[0054] As one embodiment of this application, the particle size of the hydrotalcite powder is 100-200 mesh.

[0055] Preferably, hydrotalcite powder with a particle size of 100-200 mesh is selected to improve the viscoelasticity of the mud.

[0056] It should be noted that, unless otherwise specified or indicated, the raw materials involved in the sealing gelling agent for coal mines provided in this application embodiment, such as bentonite, sodium silicate, and cellulose (specifically carboxymethyl cellulose), can be commercially available products.

[0057] Secondly, based on a general inventive concept, this application provides a method for preparing the coal mine sealing gelling agent as described in any of the first aspects, such as... Figure 1 As shown, the preparation method includes:

[0058] The modified bentonite was obtained;

[0059] The modified bentonite, calcium chloride, filler and cellulose are added to water for a second mixing to obtain the sealing gelling agent for coal mines.

[0060] The preparation method of the sealing gelling agent for coal mines provided in this application is simple to operate, requires no additional specific equipment, and is suitable for industrial production. Furthermore, this preparation method is based on the sealing gelling agent for coal mines described in any of the first aspects above, and therefore possesses at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be elaborated further here.

[0061] In one embodiment of this application, the weight of water added is 4 to 8 times the total weight of all raw materials of the coal mine sealing gelling agent.

[0062] In some specific embodiments, the weight of water added can be 4, 5, 6, 7, or 8 times the total weight of the raw materials of the coal mine sealing gelling agent.

[0063] It should be noted that, unless otherwise specified or limited, the operational steps involved in the preparation method provided in this application can be carried out in a conventional manner in the field, such as the first mixing, the second mixing, etc., can all be carried out in a conventional mixing manner.

[0064] The present application is further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the application. Experimental methods in the following embodiments that do not specify specific conditions are generally determined according to national standards. If there is no corresponding national standard, then general international standards, conventional conditions, or conditions recommended by the manufacturer are followed.

[0065] Example 1

[0066] This embodiment provides a sealing gelling agent for coal mines (wherein the modified bentonite accounts for 0.73% of the total weight of the sealing gelling agent for coal mines), and the sealing gelling agent for coal mines comprises the following components by weight (in grams):

[0067] 67.5 parts modified bentonite, 16 parts calcium chloride, 6 parts filler and 3 parts cellulose;

[0068] The method for preparing the modified bentonite includes the following steps:

[0069] Bentonite and sodium silicate in a weight ratio of 7:2 were added to water for the first mixing to obtain a slurry.

[0070] The slurry was placed in a rotating magnetic field for magnetization modification, then dried, ground, and sieved to obtain modified bentonite with a particle size of 2-5 mm. The working parameters for the magnetization modification included: the rotation speed of the rotating magnetic field was 1050 rpm, the magnetic field strength was 0.05 T, and the magnetization time was 30 min.

[0071] The filler is composed of spherical aluminum powder with a particle size of 200-300 mesh and hydrotalcite powder with a particle size of 100-200 mesh (specifically, magnesium aluminum carbonate type hydrotalcite: Mg6Al2(OH)). 16 The composition is CO3·4H2O, and the weight ratio of the spherical aluminum powder to the hydrotalcite powder is 23:2;

[0072] The cellulose is carboxymethyl cellulose.

[0073] The preparation method of the above-mentioned sealing gelling agent for coal mines includes: adding the modified bentonite, calcium chloride, filler and cellulose to water for a second mixing to obtain the sealing gelling agent for coal mines; wherein, the weight of the water added is 5 times the total weight of the raw materials of the sealing gelling agent for coal mines.

[0074] Example 2

[0075] This embodiment provides a sealing gelling agent for coal mines (wherein the modified bentonite accounts for 0.84% ​​of the total weight of the sealing gelling agent for coal mines), which differs from Embodiment 1 only in that: by weight, the sealing gelling agent for coal mines comprises the following components: 60 parts modified bentonite, 10 parts calcium chloride, 1 part filler, and 0.5 parts cellulose; the remaining steps and parameters are the same.

[0076] Example 3

[0077] This embodiment provides a sealing gelling agent for coal mines (wherein the modified bentonite accounts for 0.65% of the total weight of the sealing gelling agent for coal mines), which differs from Embodiment 1 only in that: by weight, the sealing gelling agent for coal mines comprises the following components: 75 parts modified bentonite, 25 parts calcium chloride, 10 parts filler, and 5 parts cellulose; the remaining steps and parameters are the same.

[0078] Example 4

[0079] This embodiment provides a sealing gelling agent for coal mines (wherein the modified bentonite accounts for 0.75% of the total weight of the sealing gelling agent for coal mines), which differs from Embodiment 1 only in that: by weight, the sealing gelling agent for coal mines includes the following components: 65 parts modified bentonite, 15 parts calcium chloride, 5 parts filler, and 2 parts cellulose; the remaining steps and parameters are the same.

[0080] Example 5

[0081] This embodiment provides a sealing gelling agent for coal mines (wherein the modified bentonite accounts for 0.69% of the total weight of the sealing gelling agent for coal mines), which differs from Embodiment 1 only in that: by weight, the sealing gelling agent for coal mines includes the following components: 70 parts modified bentonite, 20 parts calcium chloride, 7 parts filler, and 4 parts cellulose; the remaining steps and parameters are the same.

[0082] Example 6

[0083] This embodiment provides a sealing gelling agent for coal mines (wherein the modified bentonite accounts for 0.73% of the total weight of the sealing gelling agent for coal mines), which differs from Embodiment 1 only in that: the particle size of the modified bentonite is 6-8 mm, and the particle size of the spherical aluminum powder and the hydrotalcite powder is 400-600 mesh; the other parameters and steps are the same.

[0084] Example 7

[0085] This embodiment provides a sealing gelling agent for coal mines (in which the weight of the modified bentonite accounts for 0.73% of the total weight of the sealing gelling agent for coal mines), which differs from Embodiment 1 only in that the weight ratio of the bentonite to the sodium silicate is 1:1; all other parameters and steps are the same.

[0086] Comparative Example 1

[0087] This example provides a sealing gelling agent for coal mines, which differs from Example 1 only in that the bentonite used is unmodified bentonite; all other steps and parameters are the same.

[0088] Comparative Example 2

[0089] This example provides a sealing gelling agent for coal mines, which differs from Example 1 only in that: the modified bentonite is made by first mixing bentonite and sodium silicate in water at a weight ratio of 7:2, then drying, grinding, and sieving to obtain modified bentonite with a particle size of 2-5 mm; the remaining steps and parameters are the same.

[0090] Comparative Example 3

[0091] This example provides a sealing gelling agent for coal mines, which differs from Example 1 only in that: the modified bentonite is mixed with water to obtain a slurry; the slurry is placed in a rotating magnetic field for magnetization modification (the magnetization modification parameters are the same as in Example 1), then dried, ground, and sieved to obtain modified bentonite with a particle size of 2-5 mm; the remaining steps and parameters are the same.

[0092] Comparative Example 4

[0093] This example provides a sealing gelling agent for coal mines, which differs from Example 1 only in that the filler is spherical aluminum powder with a particle size of 200-300 mesh; the other steps and parameters are the same.

[0094] Comparative Example 5

[0095] This example provides a sealing gelling agent for coal mines, which differs from Example 1 only in that the filler is hydrotalcite powder with a particle size of 100-200 mesh (specifically, magnesium aluminum carbonate type hydrotalcite: Mg6Al2(OH)). 16 CO3·4H2O); the remaining steps and parameters are the same.

[0096] Test case

[0097] The coal mine sealing gelling agents obtained in Examples 1-7 and Comparative Examples 1-5 were subjected to performance tests, and the test results are shown in Table 1. During construction, the coal mine sealing gelling agent and fly ash (the weight of the fly ash added was four times the total weight of all raw materials in the coal mine sealing gelling agent) were mixed and then filled into the underground air leakage channels of the coal mine.

[0098] Table 1

[0099]

[0100]

[0101] In summary, this application provides a sealing gelling agent for coal mines. This sealing gelling agent uses modified bentonite, which is prepared by magnetic modification of bentonite and sodium silicate, as the main component. This not only improves the compressive strength of the gelling system but also strengthens the overall adhesion. When used in combination with fillers composed of spherical aluminum powder and hydrotalcite powder, calcium chloride, and cellulose, it can effectively improve the viscoelasticity, density, and stacking properties of the mud, thereby effectively solving the problems of poor compressive strength and poor air-stopping effect of existing inorganic sealing gelling agents.

[0102] Various embodiments of this application may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a hard limitation on the scope of this application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Furthermore, whenever a numerical range is referred to herein, it means including any referenced number (fraction or integer) within the referred range.

[0103] In this application, unless otherwise stated, directional terms such as "upper" and "lower" specifically refer to the drawing directions in the accompanying drawings. Furthermore, in the description of this application, terms such as "comprising" and "including" mean "including but not limited to." In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. In this document, "and / or" describes the relationship between related objects, indicating that three relationships can exist; for example, A and / or B can represent: A alone, A and B simultaneously, or B alone. A and B can be singular or plural. In this document, "at least one" means one or more, and "more than one" means two or more. "At least one," "at least one of the following," or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, "at least one of a, b, or c" or "at least one of a, b, and c" can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be a single or multiple.

[0104] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A sealing gelling agent for coal mines, characterized in that, The coal mine sealing gelling agent comprises the following components by weight: 60-75 parts modified bentonite, 10-25 parts calcium chloride, 1-10 parts filler and 0.5-5 parts cellulose; The modified bentonite is obtained by magnetizing and modifying a mixture of bentonite and sodium silicate; the filler is composed of spherical aluminum powder and hydrotalcite powder.

2. The sealing gelling agent for coal mines according to claim 1, characterized in that, The weight ratio of the bentonite to the sodium silicate is (5-7):(1-2).

3. The sealing gelling agent for coal mines according to claim 1 or 2, characterized in that, The method for preparing the modified bentonite includes the following steps: The bentonite and sodium silicate are added to water for a first mixing to obtain a slurry; The slurry was placed in a rotating magnetic field for magnetization modification, and then dried and ground to obtain the modified bentonite. The working parameters for the magnetization modification include: a rotational speed of 1000–1100 rpm, a magnetic field strength of 0.04–0.06 T, and a magnetization time of 20–40 min.

4. The sealing gelling agent for coal mines according to claim 3, characterized in that, The modified bentonite has a particle size of 2–5 mm.

5. The sealing gelling agent for coal mines according to claim 1, characterized in that, The modified bentonite accounts for 0.6 to 0.8% of the total weight of the coal mine sealing gelling agent.

6. The sealing gelling agent for coal mines according to claim 1, characterized in that, The weight ratio of the spherical aluminum powder to the hydrotalcite powder is (20-25):(1-2).

7. The sealing gelling agent for coal mines according to claim 6, characterized in that, The spherical aluminum powder has a particle size of 200-300 mesh.

8. The sealing gelling agent for coal mines according to claim 6, characterized in that, The particle size of the hydrotalcite powder is 100-200 mesh.

9. A method for preparing a sealing gelling agent for coal mines according to any one of claims 1 to 8, characterized in that, The preparation method includes: The modified bentonite was obtained; The modified bentonite, calcium chloride, filler and cellulose are added to water for a second mixing to obtain the sealing gelling agent for coal mines.

10. The preparation method according to claim 9, characterized in that, The weight of water added is 4 to 8 times the total weight of all raw materials of the coal mine sealing gelling agent.

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