Modified coal gangue-based large-flow-state grouting and water plugging material and preparation method thereof

Abstract

The invention provides a modified coal gangue-based large-flow-state grouting and water plugging material and a preparation method thereof. Comprising 80-90 parts of a coal gangue sample, 1-5 parts of Portland cement, 1-5 parts of sulphoaluminate cement, 0.51-3 parts of a polycarboxylic acid water reducing agent, 1-4 parts of cellulose ether with the viscosity of 200w, 0.1-5 parts of a calcium oxide expanding agent, 0.5-5 parts of a plastic expanding agent, 0.5-1 part of redispersible latex powder, 0.5-5 parts of polyacrylamide with the molecular weight of 1000 and water, and the water-material ratio is 0.4. According to the modified coal gangue-based large-flow-state grouting and water plugging material and the preparation method thereof, the cement consumption can be remarkably reduced, the cost is reduced, the utilization rate of solid wastes (such as coal gangue) is increased, and the material has good flow-state performance and adjustable setting time; the method is suitable for deep and large shaft surrounding rock water seepage treatment in coal mining and other mine engineering.

Description

Technical Field

[0001] The invention belongs to the technical field of grouting water blocking materials, and in particular relates to a modified gangue-based high-fluidity grouting water blocking material and a preparation method thereof. Background Art

[0002] In coal mining and mining engineering construction, the problem of water seepage in the surrounding rock of deep and large vertical shafts has always been an important challenge. To solve this problem, grouting water-blocking materials are widely used in water seepage control and surrounding rock reinforcement projects. Traditional grouting water-blocking materials usually use cement as the main component. For example, an inorganic ultrafine composite grouting water-blocking material is mainly composed of sulfoaluminate cement (75-85%), silicate cement (5-10%), etc., and combines the advantages of chemical grouting materials with good adhesion, fluidity and injectability. However, this type of material has the following disadvantages:

[0003] High cement usage and costs: Traditional grouting materials typically contain a high percentage of cement, significantly increasing material costs. Especially in large-scale construction, high cement usage not only increases the economic burden but also can put a certain strain on the environment.

[0004] Low solid waste utilization: With increasing environmental awareness, the comprehensive utilization of industrial solid waste (such as coal gangue) has become a research hotspot. However, most current grouting and water-blocking materials fail to fully utilize solid waste resources such as coal gangue and their potential value.

[0005] In order to solve the above problems, the present invention proposes a modified gangue-based high-fluidity grouting water blocking material and a preparation method thereof. Summary of the Invention

[0006] In view of this, the present invention addresses the shortcomings of the existing technology and provides a modified coal gangue-based high-flow grouting water-blocking material and a preparation method, which can not only significantly reduce the amount of cement used, reduce costs, and improve the utilization rate of solid waste (such as coal gangue), but also has good flow performance and adjustable setting time, and is suitable for the treatment of water seepage in surrounding rocks of deep and large vertical shafts in coal mining and other mining projects.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is: a modified coal gangue-based high-flow grouting water blocking material, including 80-90 parts of coal gangue samples, 1-5 parts of silicate cement, 1-5 parts of sulfoaluminate cement, 0.51-3 parts of polycarboxylic acid water reducer, 1-4 parts of 200w viscosity cellulose ether, 0.1-5 parts of calcium oxide expansion agent, 0.5-5 parts of plastic expansion agent, 0.5-1 part of redispersible latex powder, 0.5-5 parts of polyacrylamide with a molecular weight of 1000 and water, and the water-to-material ratio is 0.4.

[0008] A method for preparing a modified gangue-based high-fluidity grouting water-blocking material comprises the following steps:

[0009] S1, drying, drying the collected original coal gangue to remove moisture;

[0010] S2, crushing, crushing the dried gangue sample, screening the crushed gangue sample to obtain coarse gangue aggregate with a particle size of less than 5 mm;

[0011] S3, grinding, grinding the gangue coarse aggregate to produce gangue powder;

[0012] S4, stirring and mixing, after weighing the coal gangue powder, cement and additives in proportion, adding water and stirring for 3-5 minutes to prepare the coal gangue-based high-flow grouting water blocking material.

[0013] As a further improvement of the present invention, in step S1, the oven is turned on, the temperature is controlled at 105°C, and the switch is turned off after the temperature drops to room temperature to complete the drying.

[0014] As a further improvement of the present invention, in step S2, the gangue sample is crushed by a jaw crusher and sieved into gangue coarse aggregate with a particle size of less than 5 mm by an electric vibrating screen.

[0015] As a further improvement of the present invention, in step S3, the gangue coarse aggregate is ground by a ball mill. The gangue coarse aggregate is crushed into gangue powder under the impact and grinding action of the grinding medium in the ball mill. The crushed gangue powder is discharged from the ball mill through the discharge port with the help of the thrust of the feed and the flushing water, thereby completing the entire grinding process. The grinding medium is steel balls or ceramic balls, and 5.0 kg of gangue coarse aggregate is added each time.

[0016] As a further improvement of the present invention, in step S3, the crushed gangue coarse aggregate is put into a ball mill for grinding and a grinding aid is added, and mechanical activation treatment is performed. The component of the grinding aid is 1-3 parts. The addition of the grinding aid can further improve the grinding efficiency of the gangue. The grinding time is 20-30 minutes to prepare mechanically activated gangue powder; the grinding aid is a combination of any one or more of urea, sodium hexametaphosphate, instant sodium silicate, triethanolamine and triisopropanol.

[0017] As a further improvement of the present invention, in step S3, after the mechanical activation of the grinding machine is completed, the power supply of the ball mill is turned off, 1-3 parts of a modifier is added to the ball mill to modify the coal gangue, and then the grinding is continued for 10-20 minutes to complete the modification of the coal gangue powder to prepare activated and modified coal gangue powder, and the modifier is sodium methyl siliconate.

[0018] As a further improvement of the present invention, in step S4, the cement includes silicate cement and sulphoaluminate cement, and the additives include polycarboxylate water reducer, viscosity cellulose ether, calcium oxide expansion agent, redispersible latex powder and polyacrylamide.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] First, through mechanical activation and chemical modification, the activity of coal gangue is significantly improved, making it hydrophobic, and industrial solid waste (such as coal gangue) is converted into high-value-added building materials, achieving efficient utilization of resources. At the same time, the use of high-carbon emission raw materials such as cement is reduced, which is in line with the green and low-carbon development trend.

[0021] Secondly, the amount of cement used is greatly reduced (only 1-5 parts of silicate cement and 1-5 parts of sulphoaluminate cement are required). It mainly uses coal gangue as the base material. Compared with traditional grouting and water-blocking materials, the present invention significantly reduces the cost of raw materials and is particularly suitable for large-scale engineering applications.

[0022] Third, high fluidity: through the action of grinding aids and modifiers, the water demand of coal gangue is reduced, so that the grouting material has good flow properties and is convenient for construction operation; water-resistance: the surface of the modified coal gangue is hydrophobic, which enhances the overall waterproof performance of the water-blocking material and improves the water-blocking effect; adjustable setting time: by adjusting the proportion of sulphoaluminate cement, the setting time of the grouting solid body can be controlled to meet the needs of different working conditions.

[0023] Fourth, it reduces cement consumption and lowers carbon emissions; at the same time, it effectively treats industrial solid waste (such as coal gangue) and reduces the environmental burden; low-cost, high-performance grouting and water-blocking materials can significantly reduce the cost of water seepage control in coal mining and other mining projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] Figure 1 1 is an execution flow chart of the present invention. DETAILED DESCRIPTION

[0026] In order to better understand the present invention, the content of the present invention is further clearly set forth below in conjunction with the examples, but the protection content of the present invention is not limited to the following examples. In the following description, a large number of specific details are provided in order to provide a more thorough understanding of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without one or more of these details.

[0027] A modified gangue-based high-flow grouting water blocking material includes a gangue sample as a main raw material to provide a basic skeleton structure; and further includes:

[0028] Portland cement, which provides later strength and durability;

[0029] sulphoaluminate cement, which provides early strength and rapid hardening properties;

[0030] Polycarboxylate water reducer improves the fluidity of the material and reduces water consumption;

[0031] 200w viscosity cellulose ether, enhances the material's water retention and anti-delamination properties;

[0032] Redispersible latex powder improves the flexibility and bonding properties of the material;

[0033] Calcium oxide expansion agent to compensate for shrinkage and prevent cracking;

[0034] Plastic expansion agent, which produces micro-expansion during the hardening process of the paste to further compensate for the shrinkage;

[0035] Polyacrylamide with a molecular weight of 1000 improves the material's resistance to water dispersion;

[0036] Water, the amount of which is calculated based on a water-to-material ratio of 0.4, controls the fluidity and consistency of the slurry;

[0037] The water-to-material ratio refers to the ratio of the mass of water to the total mass of all solid materials (such as coal gangue, silicate cement, sulfoaluminate cement, polycarboxylic acid water reducer, cellulose ether, calcium oxide expansion agent, plastic expansion agent, redispersible latex powder and polyacrylamide).

[0038] The following describes an embodiment of the present invention based on its overall structure.

[0039] Refer to the following Figure 1 The invention describes a preparation method of the modified gangue-based high-fluidity grouting and water-blocking material.

[0040] Example 1

[0041] A method for preparing a modified gangue-based high-fluidity grouting water-blocking material comprises the following steps:

[0042] S1, drying, drying the collected original coal gangue to remove moisture;

[0043] The specific plan is as follows: after opening the oven, the heating rate is controlled at 10℃ / min; the final temperature is controlled at 105℃; after the temperature reaches 105℃, keep it for 24 hours and then turn off the switch; after the temperature drops to room temperature, the drying is completed.

[0044] S2, crushing, crush the gangue sample with a jaw crusher, and use an electric vibrating screen to screen it into coarse gangue aggregate with a particle size of less than 5 mm; the requirements for the jaw crusher used are that the spindle speed is not less than 500 r / min and the motor power is not less than 2.2 kW.

[0045] S3, grinding, grinding the gangue coarse aggregate using a ball mill to produce gangue powder;

[0046] The specific parameters are as follows: the inner diameter and length of the grinding drum are Φ500×500mm; the grinding drum speed is 60r / min;

[0047] The weight ratio of grinding medium to material is 20:1; the amount of coarse gangue aggregate added each time is 5.0 kg; the grinding medium is steel balls or ceramic balls; the grinding medium is steel balls or ceramic balls, the amount of coarse gangue aggregate added each time is 5.0 kg, and the grinding time is 25 minutes.

[0048] The gangue coarse aggregate passes through the feeding section and the inlet section and enters the grinding cylinder section; the grinding media in the grinding cylinder section and the gangue coarse aggregate generate centrifugal force as the grinding cylinder rotates. When the grinding media is lifted to a certain height, it is thrown down under the action of gravity. The gangue coarse aggregate is crushed into gangue powder under the impact and grinding action of the grinding media. The crushed gangue powder is discharged from the ball mill through the discharge port with the help of the feed and the thrust of the flushing water, thus completing the entire grinding process.

[0049] The crushed gangue coarse aggregate is put into a ball mill for grinding and at the same time, a grinding aid is added and mechanical activation treatment is carried out. The components of the grinding aid are 2 parts. The addition of the grinding aid can further improve the grinding efficiency of the gangue. The grinding time is 25 minutes to make mechanically activated gangue powder.

[0050] The principle of mechanical activation of coal gangue is based on mechanical activation. Mechanical activation refers to the introduction and accumulation of mechanical energy under the action of different mechanical forces such as grinding, compression, impact, friction, shearing and extension, thereby changing the physical and chemical properties and structure of the material, increasing the reaction activity, and stimulating and accelerating the chemical activation reaction. In this embodiment, the grinding aid is urea. In other embodiments, the grinding aid can also be any one of sodium hexametaphosphate, instant sodium silicate, triethanolamine and triisopropanol.

[0051] After the mechanical activation of the grinding is completed, the power of the ball mill is turned off, and 2 parts of the modifier are added to the ball mill for chemical activation. Then, the grinding is continued for 15 minutes to complete the modification of the coal gangue powder and prepare the activated modified coal gangue powder.

[0052] The modifier is sodium methylsiliconate; sodium methylsiliconate has alkaline and ionic characteristics, and can undergo a substitution reaction with the surface of coal gangue to form chemical bonds. In this process, methyl (-CH3) bonds to the surface of coal gangue, making the surface of coal gangue hydrophobic. The increase in hydrophobicity can reduce the water demand of coal gangue and enhance the overall waterproof performance of water plugging materials, further improving the water plugging effect. The modifier is sodium methylsiliconate.

[0053] S4, stirring and mixing, putting 90 parts of the weighed coal gangue sample, 5 parts of Portland cement, 5 parts of sulfoaluminate cement, 1 part of water reducer, 1 part of cellulose ether, 1 part of expansion agent, 1 part of redispersible latex powder and 2 parts of polyacrylamide into a mortar mixer;

[0054] The water reducer is a polycarboxylate water reducer, the expansion agent is a mixture of a calcium oxide expansion agent and a plastic expansion agent in a component ratio of 1:1, and the polyacrylamide is a polyacrylamide with a molecular weight of 1000;

[0055] Then add 40% of water of the above materials and stir; the stirring time is 4 minutes. After stirring evenly, grouting or specimen molding and related performance testing can be carried out.

[0056] Example 2

[0057] The difference from Example 1 is that 80 parts of the activated modified coal gangue sample, 15 parts of Portland cement and 5 parts of sulphoaluminate cement are used;

[0058] The rest remains the same as in Example 1.

[0059] Example 3

[0060] The difference from Example 1 is that 85 parts of the activated modified coal gangue sample, 10 parts of Portland cement and 5 parts of sulphoaluminate cement are used; the rest are consistent with Example 1.

[0061] Comparative Example 1

[0062] The difference from Example 1 is that 90 portions of the above-mentioned unactivated coal gangue samples are used, and the coal gangue samples are coal gangue samples that are not added with grinding aid components and modified components and are only ball-milled for 20 minutes; the rest are consistent with Example 1.

[0063] Comparative Example 2

[0064] The difference from Example 1 is that 80 parts of the unactivated coal gangue sample and 15 parts of Portland cement are used, and the coal gangue sample is a coal gangue sample that is not added with a grinding aid component and a modifying component and is only ball-milled for 20 minutes;

[0065] The rest remains the same as in Example 1.

[0066] Comparative Example 3

[0067] The difference from Example 1 is that 85 parts of the unactivated coal gangue sample and 10 parts of Portland cement are used, and the coal gangue sample is a coal gangue sample that is not added with a grinding aid component and a modifying component and is only ball-milled for 20 minutes;

[0068] The rest remains the same as in Example 1.

[0069] The experimental data of the relevant performance tests of the above Examples 1, 2, 3 and Comparative Examples 1, 2, 3 are compared as follows:

[0070]

[0071]

[0072] Analysis and Conclusion:

[0073] (1) Fluidity

[0074] The fluidity of Examples 1-3 is significantly higher than that of Comparative Examples 1-3, indicating that the grinding aid and modifier can effectively improve the fluidity of the material.

[0075] Among them, Example 2 has the highest fluidity (352 mm), indicating that its formulation is better.

[0076] (2) Compressive strength

[0077] The 1-day and 28-day compressive strengths of Examples 1-3 are much higher than those of Comparative Examples 1-3, indicating that mechanical activation and chemical activation can significantly improve the mechanical properties of the material.

[0078] The 28-day compressive strength of Example 2 is the highest (6.01 MPa) and the overall performance is the best.

[0079] (3) Modification effect

[0080] Grinding aids (such as urea and sodium hexametaphosphate) improve the grinding efficiency of coal gangue and reduce energy consumption.

[0081] The modifier (sodium methylsiliconate) makes the coal gangue hydrophobic, reduces the water demand and improves the waterproof performance.

[0082] Therefore, the formula of Example 2 performs best in terms of fluidity and compressive strength. This material not only realizes the efficient utilization of coal gangue resources, but also has good grouting and water blocking performance, and has important environmental and economic benefits.

[0083] The above is 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 principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A modified gangue-based high-flow grouting water-blocking material, characterized by: The method comprises 80-90 parts of coal gangue samples, 1-5 parts of silicate cement, 1-5 parts of sulfoaluminate cement, 0.51-3 parts of polycarboxylic acid water reducer, 1-4 parts of 200w viscosity cellulose ether, 0.1-5 parts of calcium oxide expansion agent, 0.5-5 parts of plastic expansion agent, 0.5-1 parts of redispersible latex powder, 0.5-5 parts of polyacrylamide with a molecular weight of 1000 and water, with a water-to-material ratio of 0.

4.

2. A method for preparing a modified gangue-based high-fluidity grouting and water-blocking material, characterized by: The steps include: S1, drying, drying the collected original coal gangue to remove moisture; S2, crushing, crushing the dried gangue sample, screening the crushed gangue sample to obtain coarse gangue aggregate with a particle size of less than 5 mm; S3, grinding, grinding the gangue coarse aggregate to produce gangue powder; S4, stirring and mixing, after weighing the coal gangue powder, cement and additives in proportion, adding water and stirring for 3-5 minutes to prepare the coal gangue-based high-flow grouting water blocking material.

3. The method for preparing the modified gangue-based high-fluidity grouting and water-blocking material according to claim 2, wherein: In step S1, the oven is turned on and the temperature is controlled at 105° C., maintained for 24 hours, and then the switch is turned off. After the temperature drops to room temperature, the drying is completed.

4. The method for preparing the modified gangue-based high-fluidity grouting and water-blocking material according to claim 3, wherein: In step S2, the coal gangue sample is crushed by a jaw crusher and sieved into coarse coal gangue aggregate with a particle size of less than 5 mm by an electric vibrating screen.

5. The method for preparing the modified gangue-based high-fluidity grouting and water-blocking material according to claim 4, characterized in that: In step S3, the gangue coarse aggregate is ground by a ball mill. The gangue coarse aggregate is crushed into gangue powder under the impact and grinding action of the grinding medium in the ball mill. The crushed gangue powder is discharged from the ball mill through the discharge port with the help of the feed and the thrust of the flushing water, thus completing the entire grinding process. The grinding medium is steel balls or ceramic balls, and 5.0 kg of gangue coarse aggregate is added each time.

6. The method for preparing the modified gangue-based high-fluidity grouting and water-blocking material according to claim 5, characterized in that: In step S3, the crushed gangue coarse aggregate is put into a ball mill for grinding and a grinding aid is added, and mechanical activation treatment is performed. The component of the grinding aid is 1-3 parts. The addition of the grinding aid can further improve the grinding efficiency of the gangue. The grinding time is 20-30 minutes to prepare mechanically activated gangue powder; the grinding aid is a combination of any one or more of urea, sodium hexametaphosphate, instant sodium silicate, triethanolamine and triisopropanol.

7. The method for preparing the modified gangue-based high-fluidity grouting and water-blocking material according to claim 6, characterized in that: In step S3, after the mechanical activation of the grinding is completed, the power of the ball mill is turned off, 1-3 parts of the modifier is added to the ball mill for chemical activation, and then the grinding is continued for 10-20 minutes to complete the modification of the coal gangue powder to prepare the activated modified coal gangue powder, and the modifier is sodium methyl siliconate.

8. The method for preparing the modified gangue-based high-fluidity grouting and water-blocking material according to claim 2, wherein: In step S4, the cement includes silicate cement and sulphoaluminate cement, and the additives include polycarboxylate water reducer, viscosity cellulose ether, calcium oxide expansion agent, redispersible latex powder and polyacrylamide.

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