Mining-induced fracture coal-based solid waste grouting filling material preparation and CO2 storage method

Abstract

The invention discloses a mining-induced fracture coal-based solid waste grouting filling material preparation and CO2 storage method, and belongs to the technical field of green mining and carbon storage. The mining-induced fracture coal-based solid waste grouting carbon sequestration filling material is prepared from the following raw materials in parts by mass: 10 to 15 parts of mixed powder, 0.2 to 2 parts of additive and 6 to 8 parts of water, wherein the mixed powder comprises the following raw materials in parts by mass: 10-20 parts of coal gangue, 5-12 parts of fly ash, 20-40 parts of coal gasification ash and 5-15 parts of furnace slag; the additive comprises styrene-acrylic emulsion and a silane coupling agent. According to the method, the styrene-acrylic emulsion and the silane coupling agent are added into the coal-based solid waste grouting carbon sequestration filling material, so that a large amount of CO2 can be stored, the coal-based solid waste grouting carbon sequestration filling material is filled into mining-induced fractures, the purpose of controlling surface movement and deformation can be achieved, and the method is a novel method capable of simultaneously achieving solid waste utilization, green filling and CO2 storage.

Description

Technical Field

[0001] This invention relates to the field of green mining and carbon sequestration technology, and in particular to a method for preparing grouting filling material for coal-based solid waste in mining fractures and for CO2 sequestration. Background Technology

[0002] The processing and utilization of coal generates large amounts of coal-based solid waste, such as coal gangue, fly ash, and coal gasification ash. When released onto the surface, this causes soil pollution and has long-term negative impacts on soil ecosystems. Simultaneously, coal development and utilization also emit large amounts of CO2, which contributes to global warming and triggers a series of environmental problems, such as glacial melting, sea-level rise, and increased extreme weather events. Therefore, facing the pressure on the ecological environment, how to safely, efficiently, and environmentally manage bulk solid waste and mineralize and store CO2 is one of the most pressing challenges that needs to be addressed.

[0003] Currently, utilizing alkali metal ions such as Ca and Mg in coal-based solid waste backfill materials to capture CO2 and prepare coal-based solid waste carbon sequestration grouting backfill materials for injection into mining-induced fracture areas can not only achieve large-scale disposal and resource utilization of coal-based solid waste, but also control surface movement and deformation. This is one of the important directions for the development of CO2 capture, storage and utilization (CCUS) technology in the coal industry. However, its application is currently limited by problems such as low efficiency and small mineralization amount in CO2 capture and storage of coal-based solid waste. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing grouting and filling materials for coal-based solid waste in mining fractures and for CO2 sequestration, so as to solve the problems existing in the prior art.

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

[0006] One of the technical solutions of the present invention is a grouting and carbon-fixing filling material for coal-based solid waste in mining fractures, comprising the following raw materials in parts by weight: 10-15 parts of mixed powder, 0.2-2 parts of additives, and 6-8 parts of water;

[0007] The mixed powder comprises the following raw materials in parts by weight: 10-20 parts coal gangue, 5-12 parts fly ash, 20-40 parts coal gasification ash, and 5-15 parts slag.

[0008] The additives include styrene-acrylic emulsions and silane coupling agents.

[0009] Furthermore, the mass ratio of the styrene-acrylic emulsion to the silane coupling agent is (10~15):(20~35).

[0010] The second technical solution of the present invention: a method for preparing the above-mentioned coal-based solid waste grouting carbon sequestration filling material, comprising the following steps:

[0011] After mixing coal gangue, fly ash, coal gasification ash and slag, the mixture is allowed to stand, then additives and water are added, mixed evenly, and carbon is fixed after vacuuming to obtain the coal-based solid waste grouting carbon-fixing filling material.

[0012] Furthermore, the mixing time is 2-5 minutes;

[0013] The settling time is 60-120 minutes.

[0014] Furthermore, the particle size of the coal gangue is 5-10 mm; the particle size of the fly ash, coal gasification ash and slag is 0-2 mm, excluding 0 mm.

[0015] Furthermore, the carbon fixation method includes introducing CO2 gas; the volume concentration of the CO2 gas is 70-100%.

[0016] The third technical solution of the present invention: a method for filling mining-induced fractures, comprising the following steps:

[0017] The above-mentioned coal-based solid waste grouting carbon sequestration filling material was used to fill the mining-induced fracture area.

[0018] Furthermore, the filling pressure is 8~15MPa.

[0019] The fourth technical solution of the present invention: a CO2 sequestration method, using the above-mentioned coal-based solid waste grouting carbon sequestration backfill material, comprising the following steps:

[0020] After mixing coal gangue, fly ash, coal gasification ash and slag, the mixture is allowed to stand. Then, additives and water are added, mixed evenly, and after vacuuming, CO2 gas is introduced for CO2 sealing.

[0021] The coal-based solid waste grouting carbon sequestration filling material of this invention has multiple functions, including solid waste filling and CO2 sequestration. By adding styrene-acrylic emulsion and silane coupling agent to the coal-based solid waste grouting carbon sequestration filling material, this invention can achieve large-scale CO2 sequestration. Filling the coal-based solid waste grouting carbon sequestration filling material into mining-induced fractures can also control surface movement and deformation. It is a novel method that can simultaneously achieve solid waste utilization, green filling, and CO2 sequestration.

[0022] The present invention discloses the following technical effects:

[0023] (1) The coal-based solid waste grouting carbon fixation filling material of the present invention does not contain cement and can realize the resource utilization and large-scale disposal of solid waste. It has the advantages of low cost, economy, green and environmental protection.

[0024] (2) The coal-based solid waste grouting carbon fixation filling material of the present invention contains styrene-acrylic emulsion and silane coupling agent, which can generate a large number of stable bubbles and increase the CO2 sequestration capacity of the coal-based solid waste grouting carbon fixation filling material. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. 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 diagram of the preparation of grouting and filling material for coal-based solid waste in mining-induced fractures and the CO2 sealing method in the embodiment. In this diagram, 1 is the raw material silo, 2 is the CO2 storage tank, 3 is the stirring and carbon fixation reaction chamber, 4 is the filling pump, 5 is the grouting and filling pipeline, 6 is the mining-induced fracture, and 7 is the coal-based solid waste grouting and carbon fixation filling material. Detailed Implementation

[0027] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0028] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0029] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0030] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0031] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0032] It should be noted that any aspects not described in detail in this invention are conventional practices in the field and are not the focus of this invention.

[0033] In a first aspect, the present invention provides a coal-based solid waste grouting and carbon sequestration filling material for mining fractures, comprising the following raw materials in parts by weight: 10-15 parts of mixed powder, 0.2-2 parts of additives, and 6-8 parts of water;

[0034] The mixed powder comprises the following raw materials in parts by weight: 10-20 parts coal gangue, 5-12 parts fly ash, 20-40 parts coal gasification ash, and 5-15 parts slag.

[0035] The additives include styrene-acrylic emulsions and silane coupling agents.

[0036] Preferably, the mass ratio of styrene-acrylic emulsion to silane coupling agent is (10~15):(20~35).

[0037] Styrene-acrylic emulsions can introduce CO2 into bubbles (bubbles generated by acrylic emulsions and silane coupling agents), increasing the amount of CO2 trapped. Silane coupling agents can effectively increase the stability of bubbles, and using this ratio can produce a large number of uniform and stable microbubbles.

[0038] Preferably, the solid content of the styrene-acrylic emulsion is 45%; the silane coupling agent is an epoxy silane coupling agent.

[0039] In a second aspect, the present invention provides a method for preparing the above-mentioned coal-based solid waste grouting carbon sequestration filling material, comprising the following steps:

[0040] (1) Put coal gangue, fly ash, coal gasification ash and slag into a mixer and mix for 2-5 minutes, then let stand for 60-120 minutes to obtain mixed powder;

[0041] (2) The mixed powder is conveyed to the stirring carbon fixation reactor (the stirring rate in the stirring carbon fixation reactor is 500 r / min) by a belt conveyor. Additives and water are added, and after mixing and stirring, the stirring carbon fixation reactor is evacuated by a vacuum pump (the negative pressure is reduced to -0.1 MPa), CO2 gas is introduced, and the mixture is stirred. After carbon fixation is completed, the CO2 gas injection is stopped, and the pressure is released to normal pressure to obtain coal-based solid waste grouting carbon fixation filling material.

[0042] The timing for the end of CO2 injection can be determined by the CO2 injection pressure and flow rate. When the CO2 flow rate remains constant and the CO2 injection pressure increases sharply, it indicates that carbon fixation is complete, and CO2 gas injection can be stopped at this point.

[0043] Use a vacuum pump to reduce the pressure inside the stirred carbon fixation reactor to -0.1 MPa. At this point, the air inside the stirred carbon fixation reactor can be extracted, allowing the reactor to be filled with CO2 gas.

[0044] Preferably, the particle size of coal gangue is 5~10mm; the particle size of fly ash, coal gasification ash and slag is 0~2mm, excluding 0mm.

[0045] Preferably, the volume concentration of CO2 gas is 70-100%.

[0046] A third aspect of the present invention provides a method for filling mining-induced fractures, comprising the following steps:

[0047] The coal-based solid waste grouting carbon-fixing filling material is transported to the mining-induced fracture area through a filling pipeline using a filling pump. After grouting is completed, the filling of the mining-induced fracture area is finished.

[0048] Preferably, the delivery pressure of the filling pump is 8~15MPa.

[0049] In a fourth aspect, the present invention provides a CO2 sequestration method, using the aforementioned coal-based solid waste grouting carbon sequestration filling material, comprising the following steps:

[0050] (1) Put coal gangue, fly ash, coal gasification ash and slag into a mixer and mix for 2-5 minutes, then let stand for 60-120 minutes to obtain mixed powder;

[0051] (2) The mixed powder is conveyed to the stirring carbon fixation reactor (the stirring rate in the stirring carbon fixation reactor is 500 r / min) by a belt conveyor. Additives and water are added, and after mixing and stirring, the stirring carbon fixation reactor is evacuated by a vacuum pump (the negative pressure is reduced to -0.1 MPa), CO2 gas is introduced, and the mixture is stirred. After carbon fixation is completed, the CO2 gas injection is stopped, and the pressure is released to normal pressure to obtain coal-based solid waste grouting carbon fixation filling material.

[0052] (3) The above-mentioned coal-based solid waste grouting carbon sequestration filling material is transported to the mining fracture area through the filling pipeline by the filling pump to complete CO2 sequestration.

[0053] The timing for the end of CO2 injection can be determined by the CO2 injection pressure and flow rate. When the CO2 flow rate remains constant and the CO2 injection pressure increases sharply, it indicates that carbon fixation is complete, and CO2 gas injection can be stopped at this point.

[0054] Preferably, the delivery pressure of the filling pump is 8~15MPa.

[0055] The CO2 sequestration method of the present invention mainly consists of two parts: a coal-based solid waste grouting carbon sequestration filling material preparation system and a filling and conveying system. It has the advantages of safety, high efficiency and low cost. It can not only realize the large-scale disposal of coal-based solid waste, but also achieve the purpose of efficient CO2 mineralization and sequestration.

[0056] The chemical composition and content of coal gangue, fly ash, coal gasification ash and slag are shown in Table 1.

[0057] Table 1. Main chemical components and contents of solid waste

[0058] chemical composition SiO2 Al2O3 CaO MgO <![CDATA[Fe2O3]]> <![CDATA[K2O]]> <![CDATA[TiO2]]> <![CDATA[SO3]]> other Coal gangue / wt% 52.21 22.27 0.56 0.56 2.71 2.28 0.93 0.98 17.50 fly ash / wt% 35.11 22.66 15.08 0.94 5.53 1.32 1.07 4.73 13.56 Slag / wt% 49.27 28.82 8.32 0.58 6.67 1.62 2.38 0.94 1.40 Coal gasification ash / wt% 43.96 31.95 2.06 0.43 8.05 1.46 0.69 1.24 10.16

[0059] Example 1

[0060] A method for preparing grouting filling material for coal-based solid waste in mining fractures and for CO2 sequestration (i.e., a method for fluidized bed filling and co-storage of coal-based solid waste in mines):

[0061] (1) 15 parts of coal gangue, 7 parts of fly ash, 30 parts of coal gasification ash and 7 parts of slag in raw material bin 1 are transported to a mixer and mixed for 3 minutes. After standing for 80 minutes, the mixed powder is obtained.

[0062] Among them, the particle size of coal gangue is 5~10mm; the particle size of fly ash, coal gasification ash and slag is 0~2mm, excluding 0mm.

[0063] (2) 12 parts of the mixed powder were conveyed to the stirring carbon fixation reaction chamber 3 (the stirring rate in the stirring carbon fixation reaction chamber 3 was 500 r / min) by a belt conveyor. 0.5 parts of the additive (the additive consisted of styrene-acrylic emulsion and silane coupling agent with a mass ratio of 12:24) and 7 parts of water were added. After mixing and stirring for 30 min, the stirring carbon fixation reaction chamber 3 was evacuated by a vacuum pump (the negative pressure was reduced to -0.1 MPa). CO2 gas was introduced into the stirring carbon fixation reaction chamber 3 through the CO2 storage tank 2. The mixture was stirred and stirred. After carbon fixation was completed, the injection of CO2 gas was stopped and the pressure was released to normal pressure to obtain the coal-based solid waste grouting carbon fixation filling material 7.

[0064] The solid content of the styrene-acrylic emulsion is 45%; the silane coupling agent is an epoxy silane coupling agent.

[0065] The volume concentration of CO2 gas is 99%. The timing of CO2 injection is determined by the CO2 injection pressure and flow rate. When the CO2 flow rate remains unchanged and the CO2 injection pressure increases sharply, it indicates that carbon fixation is complete, and CO2 gas injection can be stopped at this time.

[0066] The calculation method for CO2 sequestration volume is as follows:

[0067] The mass of the material before CO2 gas was introduced (before carbonization) was measured using an analytical balance with a weighing accuracy of 0.0001 g. The average value of three measurements was recorded as m0. After CO2 sealing (after carbonization), the mass was measured again using the balance and recorded as m1. The formula for calculating the CO2 sealing amount is as follows:

[0068] ;

[0069] In the formula, CO 2 uptake m0 represents the amount of CO2 stored; m0 represents the mass of the material before carbonization; m1 represents the mass of the material after carbonization.

[0070] (3) The coal-based solid waste grouting carbon-fixing filling material 7 is transported to the mining-induced fracture area 6 through the grouting filling pipeline 5 using the filling pump 4 (the conveying pressure of the filling pump 4 is 10MPa). After the grouting is completed, the CO2 in the mining-induced fracture is sealed.

[0071] A schematic diagram of the preparation of grouting filling material for coal-based solid waste in mining-induced fractures and the method for CO2 sequestration is shown below. Figure 1 .

[0072] Example 2

[0073] A method for preparing grouting filling material for coal-based solid waste in mining fractures and for CO2 sequestration (i.e., a method for fluidized bed filling and co-storage of coal-based solid waste in mines):

[0074] (1) 10 parts of coal gangue, 5 parts of fly ash, 20 parts of coal gasification ash and 5 parts of slag in raw material bin 1 are transported to a mixer and mixed for 3 minutes. After standing for 80 minutes, the mixed powder is obtained.

[0075] Among them, the particle size of coal gangue is 5~10mm; the particle size of fly ash, coal gasification ash and slag is 0~2mm, excluding 0mm.

[0076] (2) 10 parts of the mixed powder are conveyed to the stirring carbon fixation reaction chamber 3 (the stirring rate in the stirring carbon fixation reaction chamber 3 is 500 r / min) by a belt conveyor, 0.2 parts of admixture (the admixture is a styrene-acrylic emulsion and a silane coupling agent with a mass ratio of 10:20) and 6 parts of water are added. After mixing and stirring for 30 min, the stirring carbon fixation reaction chamber 3 is evacuated by a vacuum pump (the negative pressure is reduced to -0.1 MPa). CO2 gas is introduced into the stirring carbon fixation reaction chamber 3 through the CO2 storage tank 2. The mixture is stirred and stirred. After the carbon fixation is completed, the CO2 gas injection is stopped and the pressure is released to normal pressure to obtain the coal-based solid waste grouting carbon fixation filling material 7.

[0077] The solid content of the styrene-acrylic emulsion is 45%; the silane coupling agent is an epoxy silane coupling agent.

[0078] The volume concentration of CO2 gas is 99%. The timing of CO2 injection is determined by the CO2 injection pressure and flow rate. When the CO2 flow rate remains unchanged and the CO2 injection pressure increases sharply, it indicates that carbon fixation is complete, and CO2 gas injection can be stopped at this time.

[0079] (3) The coal-based solid waste grouting carbon-fixing filling material 7 is transported to the mining-induced fracture area 6 through the grouting filling pipeline 5 using the filling pump 4 (the conveying pressure of the filling pump 4 is 10MPa). After the grouting is completed, the CO2 in the mining-induced fracture is sealed.

[0080] Example 3

[0081] A method for preparing grouting filling material for coal-based solid waste in mining fractures and for CO2 sequestration (i.e., a method for fluidized bed filling and co-storage of coal-based solid waste in mines):

[0082] (1) 20 parts of coal gangue, 12 parts of fly ash, 40 parts of coal gasification ash and 15 parts of slag in raw material bin 1 are transported to a mixer and mixed for 3 minutes. After standing for 80 minutes, the mixed powder is obtained.

[0083] Among them, the particle size of coal gangue is 5~10mm; the particle size of fly ash, coal gasification ash and slag is 0~2mm, excluding 0mm.

[0084] (2) 15 parts of the mixed powder were conveyed to the stirring carbon fixation reaction chamber 3 (the stirring rate in the stirring carbon fixation reaction chamber 3 was 500 r / min) by a belt conveyor. 2 parts of the additive (the additive consisted of styrene-acrylic emulsion and silane coupling agent with a mass ratio of 15:35) and 8 parts of water were added. After mixing and stirring for 30 min, the stirring carbon fixation reaction chamber 3 was evacuated by a vacuum pump (the negative pressure was reduced to -0.1 MPa). CO2 gas was introduced into the stirring carbon fixation reaction chamber 3 through the CO2 storage tank 2. The mixture was stirred and stirred. After carbon fixation was completed, the injection of CO2 gas was stopped and the pressure was released to normal pressure to obtain the coal-based solid waste grouting carbon fixation filling material 7.

[0085] The solid content of the styrene-acrylic emulsion is 45%; the silane coupling agent is an epoxy silane coupling agent.

[0086] The volume concentration of CO2 gas is 99%. The timing of CO2 injection is determined by the CO2 injection pressure and flow rate. When the CO2 flow rate remains unchanged and the CO2 injection pressure increases sharply, it indicates that carbon fixation is complete, and CO2 gas injection can be stopped at this time.

[0087] (3) The coal-based solid waste grouting carbon-fixing filling material 7 is transported to the mining-induced fracture area 6 through the grouting filling pipeline 5 using the filling pump 4 (the conveying pressure of the filling pump 4 is 10MPa). After the grouting is completed, the CO2 in the mining-induced fracture is sealed.

[0088] Comparative Example 1

[0089] A method for preparing grouting filling material for coal-based solid waste in mining fractures and for CO2 sequestration (i.e., a method for fluidized bed filling and co-storage of coal-based solid waste in mines):

[0090] (1) 15 parts of coal gangue, 7 parts of fly ash, 30 parts of coal gasification ash and 7 parts of slag in raw material bin 1 are transported to a mixer and mixed for 3 minutes. After standing for 80 minutes, the mixed powder is obtained.

[0091] Among them, the particle size of coal gangue is 5~10mm; the particle size of fly ash, coal gasification ash and slag is 0~2mm, excluding 0mm.

[0092] (2) 12 parts of mixed powder are conveyed to the stirring carbonization reaction chamber 3 (the stirring rate in the stirring carbonization reaction chamber 3 is 500r / min) by a belt conveyor, 7 parts of water are added, and after mixing and stirring for 30 minutes, the stirring carbonization reaction chamber 3 is evacuated by a vacuum pump (the negative pressure is reduced to -0.1MPa), and CO2 gas is introduced into the stirring carbonization reaction chamber 3 through the CO2 storage tank 2. After mixing and stirring, after carbonization is completed, the injection of CO2 gas is stopped, and the pressure is released to normal pressure to obtain the coal-based solid waste grouting carbonization filling material 7.

[0093] The solid content of the styrene-acrylic emulsion is 45%; the silane coupling agent is an epoxy silane coupling agent.

[0094] The volume concentration of CO2 gas is 99%. The timing of CO2 injection is determined by the CO2 injection pressure and flow rate. When the CO2 flow rate remains unchanged and the CO2 injection pressure increases sharply, it indicates that carbon fixation is complete, and CO2 gas injection can be stopped at this time.

[0095] (3) The coal-based solid waste grouting carbon-fixing filling material 7 is transported to the mining-induced fracture area 6 through the grouting filling pipeline 5 using the filling pump 4 (the conveying pressure of the filling pump 4 is 10MPa). After the grouting is completed, the CO2 in the mining-induced fracture is sealed.

[0096] Example 1

[0097] The CO2 sequestration amounts for the examples and comparative examples are shown in Table 1.

[0098] Table 1 CO2 storage capacity

[0099] Group Comparative Example 1 Example 1 Example 2 Example 3 <![CDATA[CO2 Sequestration Volume]]> 0.24% 2.45% 2.36% 2.87%

[0100] As can be seen from Table 1, compared with Comparative Example 1 which did not use styrene-acrylic emulsion and silane coupling agent, the CO2 sequestration of the grouting filling materials in Examples 1-3 after treatment with styrene-acrylic emulsion and silane coupling agent was significantly higher than that in Comparative Example 1. This indicates that the bubbles generated by styrene-acrylic emulsion and silane coupling agent can significantly increase the CO2 sequestration and improve the CO2 sequestration effect of the coal-based solid waste grouting carbon sequestration filling material in mining fractures.

[0101] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A mining fissure coal-based solid waste grouting carbon sequestration filling material, characterized in that, The raw materials include the following mass fractions: 10-15 parts of mixed powder, 0.2-2 parts of additive agent, and 6-8 parts of water; The mixed powder includes the following mass fractions of raw materials: 10-20 parts of coal gangue, 5-12 parts of fly ash, 20-40 parts of coal gasification ash, and 5-15 parts of slag; The additive agent includes a benzene propyl emulsion and a silane coupling agent.

2. The coal-based solid waste grouting carbon sequestration filling material according to claim 1, characterized in that, The mass ratio of the benzene propyl emulsion and the silane coupling agent is (10-15):(20-35).

3. A method for preparing the coal-based solid waste grouting carbon sequestration filling material according to any one of claims 1-2, characterized in that, The method includes the following steps: The coal gangue, fly ash, coal gasification ash, and slag are mixed and then left to stand, and then the additive agent and water are added, mixed uniformly, and carbonized after vacuumization to obtain the coal-based solid waste grouting carbonation filling material.

4. The production method according to claim 3, characterized by, The mixing time is 2-5 min. And / or, the standing time is 60-120 min.

5. The preparation method according to claim 3, characterized in that, The particle size of the coal gangue is 5-10 mm; the particle size of the fly ash, coal gasification ash, and slag is independently 0-2 mm, and 0 mm is not included.

6. The preparation method according to claim 3, characterized in that, The carbonization method includes the introduction of CO2 gas; the volume concentration of the CO2 gas is 70-100%.

7. A method of filling mining fissures, characterized by, The method includes the following steps: The coal-based solid waste grouting carbonation filling material according to any one of claims 1-2 is used to fill a mining fissure area.

8. The filling method of claim 7, wherein, The filling pressure is 8-15 MPa.

9. A CO2 sequestration method using the coal-based solid waste grouting carbon sequestration filling material according to any one of claims 1-2, characterized in that, The method includes the following steps: The coal gangue, fly ash, coal gasification ash, and slag are mixed and then left to stand, and then the additive agent and water are added, mixed uniformly, and CO2 is introduced to perform CO2 storage after vacuumization.

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