A low-carbon room-temperature grouting material for mining, its preparation method and application

Abstract

This invention provides a novel low-carbon, room-temperature grouting material for mining, a two-component system composed of sodium silicate, inorganic acid, and nano-aluminum hydroxide, with optimized formulation enabling precise control of gel time. This material exhibits excellent permeability, high compressive strength, strong interfacial bonding, and good flame retardant properties, making it suitable for reinforcing goaf areas and treating fractures in coal mines. Compared to traditional materials, its initial setting time is adjustable within 1–50 minutes, and its final setting time is less than 80 minutes, significantly shortening the construction cycle, reducing grout loss, and improving early strength; its volume shrinkage rate is less than 4%, effectively reducing the risk of gas leakage. Industrial field tests demonstrate that this grouting material offers significant safety and economic benefits.

Description

Technical Field

[0001] This invention belongs to the field of coal mine safety engineering, specifically relating to a grouting material suitable for grouting reinforcement and sealing of micro-fractures in coal and rock masses underground in coal mines. It has the characteristics of shortening the construction cycle, reducing grout loss, and improving early strength. Background Technology

[0002] To address the challenges of high drilling resistance, stuck drill bits, and low slag return efficiency caused by geological structures during drilling in complex underground coal mine formations, grouting and sealing technology has become a key solution. This technology involves high-pressure injection of a specific grout into the fractured surrounding rock of the roadway, promoting the cementation of loose rock masses into a cohesive structure. This fundamentally optimizes the physical and mechanical properties of the surrounding rock (such as compressive strength and deformation modulus), enabling it to independently bear external loads. Compared to traditional support systems, grouting technology offers two advantages: firstly, it significantly improves the self-stability of the surrounding rock by reconstructing its microstructure, suppressing rheology in deep soft rock; secondly, it forms a high-strength reinforcement layer within the surrounding rock, providing an effective stress transfer medium for anchor bolt support. Its core technology lies in the performance control of grouting materials - the grout must have Newtonian fluid characteristics (viscosity <50mPa·s) to achieve long-distance diffusion and penetration; the gelation time must be controlled in the range of 5-30min to adapt to dynamic crack sealing; at the same time, the compressive strength of 2h is required to reach more than 5MPa to ensure that the grouting area quickly forms a load-bearing structure and ensure the continuity of mining operations and the stability of the roadway.

[0003] Traditional sealing materials are mainly divided into polyurethane-based organic materials and cement-based inorganic materials. Polyurethane materials have the characteristics of low viscosity, rapid gelation, and good ductility and flexibility, and can penetrate into tiny cracks of a few micrometers to achieve bonding to the rock mass. However, they are expensive, have high density, poor durability, low strength, and pose certain toxicity and exothermic risks, which may cause safety accidents such as coal dust combustion. Cement materials are known for their high early strength, good chemical inertness, and strong wear resistance, but they have drawbacks such as poor thixotropy, unstable performance, excessively long setting time, insufficient permeability, non-adjustable setting time, and slow improvement in early mechanical properties.

[0004] Based on field surveys and technical analyses of multiple mining areas, grouting and sealing in complex underground coal mine formations places specific demands on material performance: First, the grouting reinforcement material must have the shortest possible setting time to shorten the construction cycle; second, both early and late-stage strength must be stably guaranteed to meet the needs of repeated drilling; and third, the heat release from the reaction should be as low as possible to maintain the long-term strength stability of the material and reduce safety risks in underground operations. The inherent defects of traditional polyurethane and cement materials make it difficult to meet the comprehensive performance requirements of complex underground coal mine conditions.

[0005] Traditional grouting materials each have their shortcomings. Cement and clay-based materials have difficulty in precisely controlling their setting time, making them difficult to inject into micro-cracks. While polyurethane and its modified forms, epoxy resins, and other materials have good performance, they are expensive, cure rapidly, and generate a large amount of heat in a short time, posing a significant risk in coal mines. Therefore, addressing the problems of poor permeability, easy agglomeration and poor dispersibility of nano-reinforcing agents, unadjustable grouting setting time, low compressive strength, and weak interfacial bonding in existing grouting reinforcement materials, this invention develops a novel low-carbon, room-temperature inorganic grouting material for mining. Through formula optimization, it achieves advantages such as precisely adjustable setting time and good flame retardant properties. It can effectively penetrate micro-cracks, has a low volume shrinkage rate, and significantly reduces underground disaster risks while ensuring reinforcement strength, providing a safer and more economical solution for roadway repair under complex geological conditions. Summary of the Invention

[0006] The purpose of this invention is to provide a novel low-carbon room-temperature grouting material for mining and its application in coal mines. This grouting material adopts a two-component system design of sodium silicate, inorganic acid and nano aluminum hydroxide. Through optimized formulation, the gelation time can be precisely controlled. Moreover, the grouting reinforcement material has good permeability, high compressive strength and other strong mechanical properties, low volume shrinkage rate and good flame retardant properties, providing a safe and controllable engineering solution for underground roadway reinforcement and goaf crack treatment.

[0007] This invention provides a novel low-carbon room-temperature grouting material for mining, comprising component A and component B in a mass ratio of 4:1:

[0008] Material A comprises the following raw materials in parts by weight: 20-45 parts sodium silicate, 3-8 parts modified aluminum hydroxide, 3-10 parts nano silica powder, 1-3 parts calcium stearate, 1-5 parts calcium gluconate, 1-3 parts polycarboxylate superplasticizer, 1-10 parts additives, and water as the balance.

[0009] Material B comprises the following raw materials in parts by weight: 5-15 parts boric acid, 1-3 parts citric acid, 0.5-1 part surfactant, and water as the remainder.

[0010] Preferably, the modified aluminum hydroxide is first modified with KH570 and then modified with mercapto polyethylene glycol. Preferably, the preparation method of the modified aluminum hydroxide includes: mixing aluminum hydroxide powder and KH570 at a mass ratio of 100:5-10 for 30-60 minutes; then adding 3-5 wt% mercapto polyethylene glycol to the aluminum hydroxide, continuing to stir and mix under ultraviolet light for 30-60 minutes, and drying to obtain the modified aluminum hydroxide.

[0011] Preferably, the ultraviolet light intensity is 10-30 mW / cm², and the stirring speed is 300-600 r / min.

[0012] Preferably, the drying temperature is 80-100℃ and the drying time is 40-80 min.

[0013] Preferably, the average particle size of the nano-silicon powder is 50-150 nm, and the average particle size of the modified aluminum hydroxide is 200-500 nm.

[0014] Preferably, the mercapto polyethylene glycol is mono-mercapto polyethylene glycol and / or di-mercapto polyethylene glycol, and the molecular weight of the polyethylene glycol involved is PEG500-PEG5000.

[0015] Preferably, the surfactant in material B is at least one of sodium dodecylbenzenesulfonate, polysorbate-80, sodium dodecyl sulfate, and lignin sulfonate.

[0016] Preferably, the additives in material A include at least one of defoamer and coupling agent, wherein the defoamer is 0.5-5 parts and the coupling agent is 1-5 parts.

[0017] Preferably, the defoamer is at least one of polydimethylsiloxane and tributyl phosphate, and the coupling agent is at least one of silane coupling agent and aluminate coupling agent.

[0018] The modulus of the sodium silicate is 1.5 to 2.5.

[0019] This invention utilizes the reaction between the trimethoxysilyl group in the KH570 molecule and the hydroxyl groups on the surface of aluminum hydroxide to form a strong silicon-oxygen bond, thus attaching KH570 to the aluminum hydroxide surface. Under ultraviolet light irradiation, the thiol groups in mercapto-polyethylene glycol react with the methacryloyloxy double bonds in the KH570 molecule, causing the polyethylene glycol to attach to the aluminum hydroxide surface and enhancing hydrophilicity. Through a stepwise reaction, KH570 is first fully bonded to aluminum hydroxide before the mercapto-polyethylene glycol is introduced, which helps improve the uniformity of the modifier's coverage and the degree of reaction on the aluminum hydroxide surface, thereby more effectively improving the dispersibility of nano-aluminum hydroxide in aqueous systems.

[0020] In this invention, the pH value decreases rapidly after mixing component A and component B. The borate ions generated from the hydrolysis of boric acid react with the silicate ions in sodium silicate to form a three-dimensional network structure of borosilicate gel. The reaction of sodium silicate with citric acid increases the degree of cross-linking between silicate ions, making the gel structure denser. The added modified aluminum hydroxide and nano-silica powder, as filler and reinforcing phases, can improve the strength and rigidity of the gel and reduce volume shrinkage. Simultaneously, they can neutralize residual acidic substances, preventing corrosion of the surrounding environment and materials, further improving the performance and stability of the grouting material.

[0021] The calcium stearate and calcium gluconate used in this invention are both organic calcium salt retarder with a certain degree of surface activity. In grouting materials, they mainly have the following two effects: first, they adsorb onto the surface of silicate particles to achieve a retarding effect; second, they form a water film layer by combining with hydrogen bonds in water molecules through hydrophilic groups, encapsulating the surface of cement particles and hindering cement hydration, thus achieving a retarding effect. Calcium stearate adsorbs onto the surface of reactants or products through its hydrophobic long-chain fatty acid groups, forming an isolation film that hinders contact between reactants and improves the dispersion of reactant particles, preventing them from agglomerating too quickly. Calcium gluconate, on the other hand, generates stable complexes through coordination reactions between gluconate ions and silicate ions, reducing activity. Furthermore, its hydrolysis produces acidic substances, lowering the pH of the system and inhibiting the reaction between alkaline and acidic substances. Together, they control the crosslinking reaction rate between sodium silicate and component B in coal mine grouting materials.

[0022] The nano-silica powder and nano-aluminum hydroxide used in this invention can shorten the setting time of cement-based curing agents, reduce the time interval between initial and final setting, significantly improve the mechanical properties of filler materials such as compressive strength, and ensure stable strength growth in the later stages, while also exhibiting good flame retardant properties. Furthermore, the silica powder and nano-aluminum hydroxide have different particle sizes; utilizing this particle size difference facilitates the penetration of the grouting material into micro-cracks, resulting in a denser grout structure. The average particle size of the nano-silica powder in this invention is 50-150 nm, and the average particle size of the modified aluminum hydroxide is 200-500 nm. More preferably, the average particle size of the nano-silica powder is 50-100 nm, and the average particle size of the modified aluminum hydroxide is 300-400 nm.

[0023] Preferably, the polycarboxylate superplasticizer used in this invention has higher initial dispersibility for grouting materials compared to other types, such as naphthalene-based superplasticizers, which can improve the fluidity of grouting materials and prevent moisture loss and secondary pollution. In addition, the polycarboxylate superplasticizer can also improve surface tension, making the surface tension lower and the penetration ability stronger, thereby improving the durability of grouting materials, and has almost no inhibitory effect on its gel curing.

[0024] This invention also provides a method for preparing a novel low-carbon room-temperature grouting material for mining, specifically including the following steps:

[0025] S1: Weigh the raw materials in material A according to stoichiometry, mix the raw materials evenly, and stir at a water-cement ratio of 0.3 to 0.5:1 to obtain material A slurry;

[0026] S2: Weigh the raw materials in material B according to stoichiometry, mix the raw materials evenly, and stir at a water-cement ratio of 0.3 to 0.5:1 to obtain material B slurry.

[0027] The present invention also provides an application of a novel low-carbon room-temperature grouting material for mining in coal mines, comprising the following steps: using a grouting pump to draw grout A and grout B into a mixing pipe, and then injecting them into pre-drilled grouting holes.

[0028] The advantages or beneficial effects of the novel low-carbon room-temperature grouting material for mining of the present invention include at least the following:

[0029] The grouting material of this invention possesses excellent permeability, capable of penetrating deep into micropores and cracks in coal mine rocks—a feat difficult to achieve with conventional suspension-type grouting materials. This grouting material not only exhibits good permeability but also possesses high compressive strength and other mechanical strengths, excellent flame retardant properties, and a low volume shrinkage rate, effectively reducing the risk of gas leakage. Therefore, it provides a safe and controllable engineering solution for reinforcing underground coal mine roadways and treating fissures in goaf areas. Detailed Implementation

[0030] To more clearly illustrate the purpose, technical solution, and advantages of this invention, the technical solution of this invention will be described in detail below through specific embodiments. It should be noted that these embodiments are only for illustrating this invention and not for limiting its scope of protection; the actual scope of protection of this invention should be determined by the claims.

[0031] Unless otherwise specified, the materials and reagents used in the following examples and comparative examples are commercially available. Unless otherwise specified, the amount of each component in the following examples is 1 g per part by weight.

[0032] I. Preparation of modified aluminum hydroxide.

[0033] 1. Modified aluminum hydroxide 1#, the preparation method includes: mixing aluminum hydroxide powder with an average particle size of 200nm with KH570 at a mass ratio of 100:5 for 30min; then adding 3wt% mercapto polyethylene glycol of aluminum hydroxide powder, and continuing to mix for 30min under ultraviolet light intensity of 30mW / cm², and drying at 80℃ for 50min to obtain modified aluminum hydroxide 1#.

[0034] 2. Modified aluminum hydroxide 2#, the preparation method includes: mixing aluminum hydroxide powder with an average particle size of 300nm with KH570 at a mass ratio of 100:8 for 40min; then adding 5wt% mercapto polyethylene glycol of aluminum hydroxide powder, and continuing to mix for 30min under ultraviolet light intensity of 20mW / cm², and drying at 90℃ for 40min to obtain modified aluminum hydroxide 2#.

[0035] 3. Modified aluminum hydroxide 3#, the preparation method is the same as that of modified aluminum hydroxide 2#, the difference is that the average particle size of the aluminum hydroxide powder is 400nm.

[0036] 4. Modified aluminum hydroxide 4#, the preparation method is the same as that of modified aluminum hydroxide 2#, the difference is that the average particle size of the aluminum hydroxide powder is 500nm.

[0037] 5. Modified aluminum hydroxide 5#, the preparation method includes: mixing aluminum hydroxide powder with an average particle size of 300nm with KH570 at a mass ratio of 100:8 for 40min, continuing to mix under ultraviolet light intensity of 20mW / cm² for 30min, and drying at 90℃ for 40min to obtain modified aluminum hydroxide 5#.

[0038] 6. Modified aluminum hydroxide 6#, the preparation method includes: mixing aluminum hydroxide powder with an average particle size of 300nm with mercapto polyethylene glycol at a mass ratio of 100:5 for 40min, continuing to mix under ultraviolet light intensity of 20mW / cm² for 30min, and drying at 90℃ for 40min to obtain modified aluminum hydroxide 6#.

[0039] II. Preparation of novel low-carbon room-temperature grouting materials for mining.

[0040] This invention relates to a method for preparing a novel low-carbon room-temperature grouting material for mining, comprising material A and material B in a mass ratio of 4:1, specifically including the following steps:

[0041] S1: Preparation method of material A: According to the composition and content of material A in Table 1, use a high-speed mixer to mix at 800 r / min for 5 min, and stir at a water-cement ratio of 0.4:1 to obtain material A slurry.

[0042] S2: Preparation method of material B: According to the composition and content of material B in Table 1, use a high-speed mixer to mix at 800 r / min for 5 min, and stir at a water-cement ratio of 0.4:1 to obtain material B slurry.

[0043] Table 1: The mass fractions (g) of each component in Examples 1-7 are as follows.

[0044]

[0045] Table 2: The mass fractions (g) of each component in Comparative Examples 1-7 are as follows.

[0046]

[0047] Comparative Example 8: The difference from Example 2 is that the nano-aluminum hydroxide was not modified, while the other conditions were the same as in Example 2.

[0048] III. Performance Evaluation:

[0049] The application of the grouting materials prepared in the examples and comparative examples in coal mines includes the following steps: mixing material A and material B at a water-to-material ratio of 0.4 to form grout A and grout B respectively, and injecting grout A and grout B into pre-drilled grouting holes using a grouting pump.

[0050] 1. Stability and Liquidity Analysis

[0051] Take 50g each of the A slurry obtained from the examples and comparative examples, mix with 150g of water, and use a graduated cylinder settling method to determine the stability of the slurry, observing whether there is precipitation or other phenomena, thus characterizing the stability of the mixed slurry. The test results show that after standing for 5 minutes, there is almost no precipitation in Examples 1-7 and Comparative Examples 1-5, slight precipitation occurs in the mixed slurries of Comparative Examples 6-7, and obvious precipitation occurs in the mixed slurry of Comparative Example 8.

[0052] The fluidity of the grout was determined using standard GB / T 8077-2000. The fluidity of the A and B mixed grouts in the example and comparative examples showed no significant loss within 30 minutes, indicating excellent and stable fluidity. From a construction feasibility perspective, good fluidity helps the grout flow smoothly, fill, and penetrate into every corner and tiny gap of the construction site during grouting, improving grouting efficiency and quality, and ensuring smooth construction.

[0053] 2. Performance testing of grouting materials

[0054] The compressive strength, tensile strength, shear strength, and bond strength of the grouting material were tested according to the requirements of AQ / T 1089-2020 standard. The initial setting time and final setting time of the grouting material were tested according to the "Standard for Test Methods of Performance of Ordinary Concrete Mixtures" (GB / T50080-2016); the volume shrinkage rate was tested according to GB / T 13477.19-2019 "Test Methods for Building Sealing Materials". The test results are shown in Table 3.

[0055] Table 3. Performance of grouting materials in different embodiments and comparative examples.

[0056]

[0057] According to the data in Performance Test Table 3, the grouting material prepared by this invention exhibits high mechanical strength for coal mine filling, with compressive strength, tensile strength, shear strength, and bond strength exceeding 40 MPa, 5.5 MPa, 16 MPa, and 3.5 MPa, respectively, significantly improving the overall safety of soft and fractured coal and rock strata. Furthermore, its initial setting time is less than 50 min, and its final setting time is less than 80 min, with a short interval between initial and final setting, significantly shortening the construction cycle, enhancing the grouting effect, reducing grout loss, improving early strength, and reducing monitoring waiting time. The volume shrinkage rate of the grouting material of this invention is less than 4%, with minimal volume change during curing, indicating that the grouting material can more tightly fill the pores and fissures of the coal and rock mass, reducing porosity caused by material shrinkage, thereby reducing the risk of gas leakage and avoiding geological disasters and safety hazards. Simultaneously, the aluminum hydroxide contained in the grouting material possesses good flame retardancy, and all raw materials are inorganic, further enhancing the flame retardant performance of the grouting material.

[0058] A comparison of Examples 4-5 with Examples 2 and 6-7 shows that the preferred combination is a nano-silicon powder with an average particle size of 50-100 nm and a modified aluminum hydroxide with an average particle size of 300-400 nm. The silicon powder and nano-aluminum hydroxide have different particle sizes. Utilizing their particle size difference facilitates the entry of the grouting material into the micro-cracks, making the grout structure more compact, significantly improving the mechanical strength of the coal mine filling, and reducing the volume shrinkage rate and setting time.

[0059] Comparing the results of Example 2 with those of Comparative Examples 1-2, it can be seen that Comparative Example 1, by omitting boric acid, could not form a three-dimensional network of borosilicate gel. This resulted in a slower solidification rate, significantly reduced mechanical strength, and a markedly increased volume shrinkage rate of the grouting material. Furthermore, Comparative Example 2, by not using nano-silica powder, also showed a significant decrease in both mechanical strength and solidification time interval of the grouting material.

[0060] Comparing Example 2 with Comparative Examples 3-4, it was found that using only calcium stearate or calcium gluconate as a retarder, while having little effect on the mechanical strength and volume shrinkage rate of the coal mine grout, significantly prolonged the time interval between initial and final setting. This increased the monitoring waiting time, making it difficult to meet the construction requirements for rapid filling and curing. Therefore, the synergistic effect of calcium stearate and calcium gluconate is needed to effectively control the crosslinking reaction rate of sodium silicate and component B in the coal mine grouting material.

[0061] A comparison of Example 2 with Comparative Examples 5-8 reveals that nano-aluminum hydroxide, without modification or only modified with KH570 or mercapto-polyethylene glycol, exhibits decreased hydrophilicity and poor dispersibility in aqueous systems. This prevents the grouting material from tightly filling the pores and fissures of the coal and rock mass, resulting in reduced mechanical strength and increased volume shrinkage of the coal filling material, significantly impacting its performance.

[0062] 3. Industrial field test

[0063] To save on experimental costs and ensure a clear comparison, the grouting materials used in Examples 2, 4-5, and Comparative Examples 1-8 were selected for grouting and sealing in the coal mine field test. Representative test holes were chosen to ensure consistency in drilling parameters, including a grouting pressure of 1.5 MPa, a hole diameter of 100 mm, and a hole depth of 10 m. After one month of field observation, the changes in gas concentration in the test and control boreholes were recorded. Details are shown in Table 4 below.

[0064] Table 4 Results of Industrial Field Tests

[0065]

[0066] According to the data in Table 4, the gas extraction concentration of the boreholes sealed in Examples 2 and 4-5 was significantly higher than that in Comparative Examples 1-8, and this difference became more significant with increasing extraction time. Specifically, the average gas extraction concentration in Examples 2 and 4-5 was 6-13% higher than that in the comparative examples, and by day 30, the concentration was 20-30% higher. This indicates that the rate of decrease in gas extraction concentration in the examples was significantly reduced. This result confirms that the grouting material of the present invention performs excellently in sealing fractures and pores in coal and rock masses, effectively preventing gas leakage, reducing gas leakage inside and outside the borehole, and thus significantly extending the effective extraction cycle of the borehole.

[0067] The above embodiments are merely examples to illustrate the present invention and are not intended to limit the possible implementations of the invention. Based on the disclosure of this invention, those skilled in the art can make various modifications and adjustments. It is neither possible nor necessary to list all possible implementations. Any modifications, equivalent substitutions, or improvements made within the basic principles and scope of this invention should be considered to fall within the protection scope of this invention.

Claims

1. A low-carbon, room-temperature grouting material for mining, characterized in that, This includes material A and material B in a mass ratio of 4:1: Material A includes the following raw materials in parts by weight: 20-45 parts sodium silicate, 3-8 parts modified aluminum hydroxide, 3-10 parts nano silica powder, 1-3 parts calcium stearate, 1-5 parts calcium gluconate, 1-3 parts polycarboxylate superplasticizer, 1-10 parts additives, and water as the balance. Material B comprises the following raw materials in parts by weight: 5-15 parts boric acid, 1-3 parts citric acid, 0.5-1 part surfactant, and water as the balance; The preparation method of the modified aluminum hydroxide includes: mixing aluminum hydroxide powder with KH570 at a mass ratio of 100:5-10 for 30-60 minutes; Then, 3-5 wt% of mercapto polyethylene glycol was added to aluminum hydroxide, and the mixture was stirred and mixed for 30-60 minutes under ultraviolet light, and then dried to obtain modified aluminum hydroxide.

2. The low-carbon, room-temperature grouting material for mining as described in claim 1, characterized in that, The ultraviolet light intensity is 10-30 mW / cm², the stirring speed is 300-600 r / min, the drying temperature is 80-100℃, and the drying time is 40-80 min.

3. The low-carbon, room-temperature grouting material for mining as described in claim 1, characterized in that, The average particle size of the nano-silicon powder is 50-150 nm, and the average particle size of the modified aluminum hydroxide is 200-500 nm.

4. The low-carbon, room-temperature grouting material for mining as described in claim 3, characterized in that, The average particle size of the nano-silicon powder is 50-100 nm, and the average particle size of the modified aluminum hydroxide is 300-400 nm.

5. The low-carbon, room-temperature grouting material for mining as described in claim 1, characterized in that, The thiol polyethylene glycol is monothiol polyethylene glycol and / or dithiol polyethylene glycol, and the polyethylene glycol involved is PEG500-PEG5000.

6. The low-carbon, room-temperature grouting material for mining as described in claim 1, characterized in that, The surfactant in material B is at least one of sodium dodecylbenzenesulfonate, polysorbate-80, sodium dodecyl sulfate, and lignin sulfonate.

7. The low-carbon, room-temperature grouting material for mining as described in claim 1, characterized in that, The additives in material A include at least one of defoamer and coupling agent, wherein the defoamer is 0.5-5 parts and the coupling agent is 1-5 parts.

8. The low-carbon, room-temperature grouting material for mining as described in claim 7, characterized in that, The defoamer is at least one of polydimethylsiloxane and tributyl phosphate, and the coupling agent is at least one of silane coupling agent and aluminate coupling agent.

9. A method for preparing a low-carbon, room-temperature grouting material for mining as described in any one of claims 1-8, characterized in that, Specifically, the following steps are included: Weigh the raw materials in material A according to stoichiometry, and stir them at a water-cement ratio of 0.3 to 0.5:1 to obtain material A slurry; weigh the raw materials in material B according to stoichiometry, and stir them at a water-cement ratio of 0.3 to 0.5:1 to obtain material B slurry.

10. The application of a low-carbon, room-temperature grouting material for mining as described in any one of claims 1-8 or the low-carbon, room-temperature grouting material for mining prepared according to claim 9 in coal mines, characterized in that, Includes the following steps: Material A and material B are respectively sucked into the mixing pipe by the grouting pump and then injected into the pre-drilled grouting holes.

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