All-solid-waste mine functional cementing material, preparation method and application

Abstract

The application discloses a kind of full solid waste mine functional cementing material, preparation method and application, the cementing material is realized by using organic mineralization reinforcing admixture " alkali excitation-sulfate excitation-mineralization reinforcement " triple synergistic mechanism realizes high performance, simultaneously reduces energy consumption, and cost is lower.

Description

Technical Field

[0001] This invention relates to the field of solid waste resource utilization technology, and in particular to a functional cementing material for solid waste mining, its preparation method, and its application. Background Technology

[0002] Coal mining generates large amounts of fly ash (FA), desulfurized gypsum (FGD), and carbide slag (CCR), whose stockpiling occupies land and pollutes the environment. Utilizing these solid wastes to prepare mining cementitious materials is a key approach to achieving green mines. However, existing solid waste-based cementitious materials have the following problems: 1. Low early strength: The 3-day strength of traditional solid waste cementitious materials is usually less than 1.0 MPa, which is difficult to meet the requirements of rapid underground support; 2. Poor volume stability: The complex composition of solid waste makes it prone to shrinkage cracking, affecting the compactness of the filling body and the roof contact rate; 3. Weak erosion resistance: Under long-term erosion by mine water (especially containing sulfates), the strength is prone to decline; 4. Low mineralization efficiency: The active calcium components (such as Ca(OH)2) in solid waste react slowly with CO2, resulting in limited natural mineralization effects.

[0003] Existing improvement methods mostly focus on mechanical activation or the addition of silicate cement clinker, but the former is energy-intensive, and the latter deviates from the "all-solid-waste" concept. Therefore, how to reduce energy consumption and save costs while ensuring the performance of cementitious materials has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0004] This application provides a functional cementing material for solid waste mining, its preparation method, and its application. This cementing material achieves high performance by using an organic mineralization-enhancing additive to realize a triple synergistic mechanism of "alkali activation-sulfate activation-mineralization enhancement," while reducing energy consumption and lowering costs.

[0005] In a first aspect, the present invention provides a functional cementing material for all-solid waste mining, the cementing material comprising the following components: an all-solid waste substrate and an organic mineralization reinforcing additive; wherein the all-solid waste substrate comprises fly ash, desulfurized gypsum, and carbide slag; the organic mineralization reinforcing additive comprises the following components: a mineralization accelerator and a toughening and stabilizing agent; the mineralization accelerator comprises the following components: sodium acryloyl dimethyl taurate, phytic acid-chitosan polymer, and tridecafluorooctyltriethoxysilane; the toughening and stabilizing agent comprises the following components: cyclodextrin-modified lignin sulfonate, cellulose aerogel microspheres, and triethanolamine borate.

[0006] In some embodiments, the components of the cementing material include 100 parts by weight of all-solid waste substrate and 3-6 parts by weight of organic mineralization reinforcing additive; wherein, 1.5-3 parts are mineralization accelerator and 1.5-3 parts are toughening and stabilizing agent.

[0007] In some embodiments, the all-solid-waste substrate further includes steel slag powder or slag powder.

[0008] Secondly, the present invention provides a method for preparing a functional cementing material for all-solid waste mining, comprising:

[0009] The solid waste substrate is pretreated to obtain the pretreated solid waste substrate, which includes pulverized fly ash, pulverized desulfurized gypsum and pulverized and aged carbide slag.

[0010] Preparation of mineralization accelerators and toughening and stabilizing agents;

[0011] Mineralization accelerators and toughening stabilizers are mixed to form an organic mineralization reinforcing admixture;

[0012] The ground fly ash, ground desulfurized gypsum, and ground and aged carbide slag are mixed to obtain a mixed substrate. The organic mineralization reinforcing additive is added to the mixed substrate in multiple batches for mixing. The interval between each addition of the organic mineralization reinforcing additive is a first preset time, and the total mixing time is greater than or equal to a second preset time.

[0013] In some embodiments, the step of preparing the mineralization promoter includes:

[0014] Sodium acryloyl dimethyl taurate was dissolved in deionized water to prepare a first solution with a mass fraction of 20%.

[0015] Phytic acid-chitosan polymer is added to the first solution under constant stirring to form a first mixture;

[0016] After adding tridecafluorooctyltriethoxysilane dropwise to the first mixture, the reaction was carried out at 60°C for 2 hours to obtain the reaction solution;

[0017] The reaction solution was spray-dried to obtain a mineralization accelerator.

[0018] In some embodiments, the step of preparing the toughening and stabilizing agent includes:

[0019] Calcium lignin sulfate was dissolved in deionized water to prepare a second solution with a mass fraction of 25%.

[0020] Cellulose aerogel microspheres were added to the second solution and ultrasonically dispersed to obtain a second mixture;

[0021] After adding triethanolamine borate to the second mixture, the mixture was reacted at 80°C for 1.5 hours to obtain the third mixture;

[0022] The third mixture is dried and pulverized to obtain a toughening and stabilizing agent.

[0023] In some embodiments, the step of pretreating the solid waste substrate to obtain the pretreated solid waste substrate includes:

[0024] The calcium carbide slag should be naturally aged for at least seven days to fully dissolve the residual calcium carbide; the aged calcium carbide slag should be ground until the specific surface area is greater than or equal to 350 m². 2 / kg;

[0025] Fly ash and desulfurized gypsum were ground separately until the residue on an 80μm sieve was ≤10%, thus obtaining ground fly ash and ground desulfurized gypsum respectively.

[0026] In some embodiments, the first preset time is 3 minutes, and the second preset time is greater than or equal to 15 minutes.

[0027] Thirdly, the present invention provides an application of a functional cementing material for all-solid waste mining, characterized in that it is used for filling goaf areas, roadway support, and foundation reinforcement in coal mines.

[0028] In some embodiments, the method of the application includes:

[0029] The cementitious material and water are mixed and stirred to obtain a slurry;

[0030] Carbon dioxide is introduced into the slurry, and the introduction of carbon dioxide is stopped when the pH value of the slurry reaches 12; the slurry after the introduction of carbon dioxide is injected into the target area.

[0031] This invention provides a functional cementing material for solid waste mining, its preparation method, and its application. This cementing material achieves high performance by using an organic mineralization-enhancing additive to realize a triple synergistic mechanism of "alkali activation-sulfate activation-mineralization enhancement," while reducing energy consumption and lowering costs. Attached Figure Description

[0032] Figure 1 A flowchart illustrating an exemplary method for preparing a functional cementitious material for all-solid waste mining, according to some embodiments, is shown. Detailed Implementation

[0033] To better understand the above technical solutions, the technical solutions of this application will be described in detail below through specific implementation methods.

[0034] Coal mining generates large amounts of fly ash, desulfurization gypsum, and carbide slag, which occupy land and pollute the environment when stockpiled. Utilizing these solid wastes to prepare mining cementitious materials is a key approach to achieving green mines. However, existing solid waste-based cementitious materials have the following problems: 1. Low early strength: The 3-day strength of traditional solid waste cementitious materials is usually less than 1.0 MPa, which is difficult to meet the requirements of rapid underground support; 2. Poor volume stability: The complex composition of solid waste makes it prone to shrinkage cracking, affecting the compactness of the filling body and the roof contact rate; 3. Weak erosion resistance: Under long-term erosion by mine water (especially containing sulfates), the strength is prone to decline; 4. Low mineralization efficiency: The active calcium components (such as Ca(OH)2) in solid waste react slowly with CO2, resulting in limited natural mineralization effect.

[0035] Existing improvement methods mostly focus on mechanical activation or the addition of silicate cement clinker, but the former is energy-intensive, and the latter deviates from the "all-solid-waste" concept. Therefore, how to reduce energy consumption and save costs while ensuring the performance of cementitious materials has become a technical problem that urgently needs to be solved by those skilled in the art.

[0036] To address the aforementioned technical issues, this application provides a functional cementing material for solid waste mining, its preparation method, and its application. This cementing material achieves high performance by using an organic mineralization-enhancing additive to realize a triple synergistic mechanism of "alkali activation-sulfate activation-mineralization enhancement," while simultaneously reducing energy consumption and lowering costs.

[0037] This application provides a functional cementing material for all-solid waste mining, comprising the following components: an all-solid waste substrate and an organic mineralization reinforcing additive; wherein the all-solid waste substrate includes fly ash, desulfurized gypsum, and carbide slag; the organic mineralization reinforcing additive includes the following components: a mineralization accelerator and a toughening and stabilizing agent; the mineralization accelerator includes the following components: sodium acryloyl dimethyl taurate, phytic acid-chitosan polymer, and tridecafluorooctyltriethoxysilane; the toughening and stabilizing agent includes the following components: cyclodextrin-modified lignin sulfonate, cellulose aerogel microspheres, and triethanolamine borate.

[0038] The cementing material in this embodiment achieves high performance through a triple synergistic mechanism of "alkali activation-sulfate activation-mineralization enhancement":

[0039] 1. Alkali activation: Ca(OH)2 in carbide slag provides a strongly alkaline environment (pH>12.5), which dissolves the Si-O and Al-O bonds in the fly ash glass, releasing active SiO2 and Al2O3.

[0040] 2. Sulfate activation: Desulfurized gypsum provides SO4. 2- Ca 2+ It reacts with Al2O3 dissolved in fly ash under alkaline conditions to form ettringite (AFt), which contributes to early strength.

[0041] 3. Enhanced mineralization: The sulfonic acid groups of sodium acryloyldimethyl taurate chelate with active Al2O3 in fly ash, promoting the dissolution of carbide slag (Ca(OH)2) and releasing Ca. 2+ Simultaneously, the phytic acid-chitosan polymer guides the directional crystallization of mineralized nano-calcium carbonate through phosphate groups, while the hydrophobic effect of tridecafluorooctylsilane reduces water evaporation channels. These three components synergistically form a dense hydration product network, enhancing early strength. Cyclodextrin-modified lignin sulfonate adsorbs SO4 from desulfurized gypsum through β-cyclic cavities. 2- It delays coagulation, while the B(OH)4 produced by the hydrolysis of triethanolamine borate esters... - With Ca 2+ Dynamic [BO-Ca] crosslinking bonds are formed, and cellulose aerogel microspheres serve as a nano-reinforcing framework, together constructing a dual effect of "retardation-reinforcement" to improve the 28-day strength.

[0042] 4. Synergistic effect: The alkaline environment provided by carbide slag activates the silica-alumina phase in fly ash, and the SO3 in desulfurized gypsum synergistically generates ettringite (AFt) and aluminosilicate phosphate (CAPH) with the phosphorus groups of phytic acid-chitosan. Aerogel microspheres form a high-strength organic-inorganic hybrid structure through interlayer ion exchange, which significantly improves compressive strength.

[0043] In some embodiments, the components of the cementing material include 100 parts by weight of all-solid waste substrate and 3-6 parts by weight of organic mineralization reinforcing additive; wherein, 1.5-3 parts are mineralization accelerator and 1.5-3 parts are toughening and stabilizing agent.

[0044] In some embodiments, the all-solid-waste substrate comprises, by weight, 40-60 parts fly ash, 15-25 parts desulfurized gypsum, and 25-35 parts carbide slag. In some embodiments, the fly ash is selected as Grade II fly ash, wherein SiO2+Al2O3+Fe2O3≥70% and loss on ignition≤8%. The desulfurized gypsum contains ≥85% CaSO4·2H2O. The carbide slag contains ≥65% Ca(OH)2 and requires aging for ≥7 days.

[0045] In some embodiments, the all-solid-waste substrate further includes steel slag powder or slag powder.

[0046] In this embodiment, the activity of steel slag powder and slag powder is higher than that of fly ash, and adding some steel slag powder or slag powder can improve the early strength.

[0047] In some embodiments, the components of the all-solid waste substrate, by weight, include 40-60 parts fly ash, 15-25 parts desulfurized gypsum, and 25-35 parts carbide slag, and further include 0-5 parts steel slag powder or 0-5 parts blast furnace slag powder. In some embodiments, the specific surface area of ​​the steel slag powder is ≥400 m². 2 / kg. In some embodiments, the D50 of the slag powder is ≤30μm.

[0048] This application also provides a method for preparing a functional cementing material for all-solid waste mining. Figure 1 A flowchart illustrating an exemplary method for preparing a functional cementitious material for solid waste mining, according to some embodiments, is provided. The method includes steps S100-S500.

[0049] S100. Pre-treat the solid waste substrate to obtain the pre-treated solid waste substrate.

[0050] In some embodiments, the step of pretreating the solid waste substrate to obtain the pretreated solid waste substrate includes:

[0051] The calcium carbide slag should be naturally aged for at least seven days to fully dissolve the residual calcium carbide; the aged calcium carbide slag should be ground until the specific surface area is greater than or equal to 350 m². 2 / kg;

[0052] Fly ash and desulfurized gypsum were ground separately until the residue on an 80μm sieve was ≤10%, thus obtaining ground fly ash and ground desulfurized gypsum respectively.

[0053] In some embodiments, if the solid waste substrate also includes steel slag powder or slag powder, the steel slag powder or slag powder is also ground to a residue of ≤10% on an 80μm sieve. The ground steel slag powder and slag powder are then mixed with ground fly ash, ground desulfurized gypsum, and ground and aged carbide slag to obtain the pretreated solid waste substrate.

[0054] S200, preparation of mineralization accelerator.

[0055] In some embodiments, the step of preparing the mineralization promoter includes:

[0056] Sodium acryloyl dimethyl taurate was dissolved in deionized water to prepare a first solution with a mass fraction of 20%.

[0057] A phytic acid-chitosan polymer is added to the first solution under continuous stirring to form a first mixture; wherein the phytic acid-chitosan polymer is formed by the self-assembly of bio-based phytic acid and chitosan at a mass ratio of 2:1. In one example, the rotation speed corresponding to the continuous stirring of the first solution is 1000 rpm.

[0058] After adding tridecafluorooctyltriethoxysilane dropwise to the first mixture, the reaction was carried out at 60°C for 2 hours to obtain the reaction solution;

[0059] The reaction solution was spray-dried to obtain a mineralization accelerator.

[0060] In one example, 100g of sodium acryloyldimethyl taurate (Mw≈3000) was dissolved in 500ml of deionized water to prepare a 20% first solution. 15g of phytic acid-chitosan polymer was added to the first solution with continuous stirring, followed by the dropwise addition of 5ml of tridecafluorooctyltriethoxysilane. The mixture was reacted at 60°C for 2 hours to obtain a reaction solution. The reaction solution was spray-dried to obtain a white powdery mineralization accelerator.

[0061] In this embodiment, the sulfonic acid group of sodium acryloyldimethyl taurate chelates with active Al2O3 in fly ash, promoting the dissolution of carbide slag (Ca(OH)2) and releasing Ca. 2+ Simultaneously, the phytic acid-chitosan polymer guides the directional crystallization of mineralized nano-calcium carbonate through phosphate groups, while the hydrophobic effect of tridecafluorooctylsilane reduces moisture evaporation channels. These three components synergistically form a dense network of hydration products, enhancing early strength. Phytic acid (a bio-based phosphorus source) and chitosan (a nitrogen source) form an intumescent flame-retardant system, generating a dense phosphoric acid-char layer at high temperatures, exhibiting flame-retardant properties.

[0062] S300, Preparation of toughening and stabilizing agent.

[0063] In some embodiments, the step of preparing the toughening and stabilizing agent includes:

[0064] Calcium lignin sulfate was dissolved in deionized water to prepare a second solution with a mass fraction of 25%.

[0065] Cellulose aerogel microspheres were added to the second solution and ultrasonically dispersed to obtain a second mixture;

[0066] After adding triethanolamine borate to the second mixture, the mixture was reacted at 80°C for 1.5 hours to obtain the third mixture;

[0067] The third mixture is dried and pulverized to obtain a toughening and stabilizing agent.

[0068] In one example, 100g of cyclodextrin-modified lignin sulfonate was dissolved in 400ml of deionized water to prepare a second solution with a mass fraction of 25%. 10g of cellulose aerogel microspheres were added and ultrasonically dispersed for 30 minutes to obtain a second mixture. 10g of triethanolamine borate was added to the second mixture, and the mixture was reacted at 80°C for 1.5 hours to obtain a third mixture. The third mixture was dried and pulverized to obtain a brown powdery toughening and stabilizing agent.

[0069] In this embodiment, cyclodextrin-modified lignin sulfonate adsorbs SO4 from desulfurized gypsum through β-cyclic cavities. 2- It delays coagulation, while the B(OH)4 produced by the hydrolysis of triethanolamine borate esters... - With Ca 2+Dynamic [BO-Ca] crosslinking bonds are formed, and cellulose aerogel microspheres serve as a nano-reinforcing framework, together constructing a dual effect of "retardation-reinforcement" to improve the 28-day strength.

[0070] In some embodiments, the preparation method of cellulose aerogel microspheres includes: 1. Solution preparation: 1.1 Coagulation bath preparation: Prepare a 5% CaCl2 aqueous solution (or anhydrous ethanol) as a coagulation bath and let it stand for later use. 1.2 Preparation of cellulose solution: Dissolve 7g NaOH and 12g urea in 81g of deionized water pre-cooled to -15℃ and stir to dissolve. Add 4g microcrystalline cellulose (MCC) and stir continuously for 30 minutes until a transparent viscous solution is formed. 2. Hydrogel sphere molding: 2.1 Titration operation: Draw the cellulose solution into a syringe. Drop it uniformly into the coagulation bath from a height of 5–10cm (1–2 drops / second) to form gel microspheres with a diameter of 1–3mm. 2.2 Gel curing: Let the microspheres stand in the coagulation bath for ≥30 minutes to complete curing. 2.3 Solvent replacement: Wash the gel spheres 3 times with deionized water, and then soak them in anhydrous ethanol for 12 hours. 3. Freeze-drying and post-treatment: 3.1 Freeze-drying: Dry in a freeze dryer (-50℃, ≤10Pa) for 24–48 hours to obtain white porous cellulose aerogel microspheres.

[0071] S400: Mineralization accelerator and toughening stabilizer are mixed to form an organic mineralization reinforcing admixture.

[0072] S500. After mixing the ground fly ash, ground desulfurized gypsum and ground and aged carbide slag, a mixed substrate is obtained. The organic mineralization reinforcing additive is added to the mixed substrate in multiple batches for mixing. The interval between each addition of the organic mineralization reinforcing additive is a first preset time, and the total mixing time is greater than or equal to a second preset time.

[0073] In this embodiment, the total mixing time includes the time for mixing to obtain the mixed substrate, and the sum of the mixing time after adding the organic mineralization reinforcing additive.

[0074] For example, the ground fly ash, ground desulfurized gypsum and ground and aged carbide slag are dry-mixed in a forced mixer for 10-15 minutes until uniform to obtain a mixed substrate.

[0075] In some embodiments, the first preset time is 3 minutes, and the second preset time is greater than or equal to 15 minutes.

[0076] In some embodiments, the adhesive material is inspected, and after passing the inspection, it is sealed and packaged.

[0077] This application also provides an application of a functional cementing material for all-solid waste mining, used for filling goaf areas, roadway support, and foundation reinforcement in coal mines.

[0078] In some embodiments, the method of the application includes:

[0079] The cementitious material and water are mixed and stirred to obtain a slurry;

[0080] Carbon dioxide is introduced into the slurry, and the introduction of carbon dioxide is stopped when the pH value of the slurry reaches 12; the slurry after the introduction of carbon dioxide is injected into the target area.

[0081] In this embodiment, the cementing material and water are mixed and stirred to obtain a slurry. Then, the pH of the slurry is controlled to reach 12 by carbon dioxide or flue gas carbon dioxide with a concentration greater than 0 and less than or equal to 100%, and the carbon dioxide is stopped. Then, the slurry with carbon dioxide is injected into the target area.

[0082] Example 1:

[0083] The solid waste substrate consists of 50 parts fly ash, 20 parts desulfurized gypsum, and 30 parts carbide slag.

[0084] The organic mineralization enhancing admixture includes 2.0 parts of mineralization accelerator and 2.0 parts of toughening and stabilizing agent.

[0085] The solid waste substrate is pretreated to obtain the pretreated solid waste substrate, which includes pulverized fly ash, pulverized desulfurized gypsum and pulverized aged carbide slag; mineralization accelerator and toughening stabilizer are mixed to form an organic mineralization reinforcing additive.

[0086] The ground fly ash, ground desulfurized gypsum, and ground and aged carbide slag were dry-mixed for 12 minutes. Then, an organic mineralization reinforcing admixture was added in three batches, with a 3-minute interval between each addition, for a total mixing time of 18 minutes. The cementing material and water were mixed at a water-cement ratio of 0.45 to obtain a slurry. CO2 was introduced into the slurry to control the pH at 12, and then the CO2 introduction was stopped. The slurry with CO2 introduced was then injected into the target area with a cement-sand ratio of 1:4 (standard sand).

[0087] Example 2:

[0088] Unlike Example 1, the all-solid waste substrate includes 45 parts fly ash, 18 parts desulfurized gypsum, 32 parts carbide slag, and 5 parts steel slag powder.

[0089] The organic mineralization enhancing admixture includes 2.5 parts of mineralization accelerator and 1.5 parts of toughening and stabilizing agent.

[0090] Example 3:

[0091] Unlike Example 1, the all-solid waste substrate includes 55 parts fly ash, 25 parts desulfurized gypsum, and 20 parts carbide slag.

[0092] The organic mineralization enhancing admixture includes 1.8 parts of mineralization accelerator and 2.2 parts of toughening and stabilizing agent.

[0093] Example 4:

[0094] Unlike Example 1, the all-solid waste substrate includes 40 parts fly ash, 20 parts desulfurized gypsum, 35 parts carbide slag, and 5 parts slag powder.

[0095] The binder and water were mixed and stirred at a water-to-binder ratio of 0.42 to obtain a slurry.

[0096] Example 5:

[0097] Unlike Example 1, the all-solid-waste substrate includes 60 parts fly ash, 15 parts desulfurized gypsum, and 25 parts carbide slag.

[0098] The organic mineralization enhancing admixture includes 1.5 parts of mineralization accelerator and 1.5 parts of toughening and stabilizing agent.

[0099] Comparative Example 1:

[0100] Unlike Example 1, 100 parts of pure cement-based material were used to replace 100 parts of all-solid-waste base material. The cement-based material was P·O42.5 cement.

[0101] Comparative Example 2:

[0102] Unlike Example 1, no organic mineralization enhancement additives were used.

[0103] Comparative Example 3:

[0104] Unlike Example 1, only a mineralization accelerator was used, without a toughening and stabilizing agent, wherein the mineralization accelerator was in a fraction of 4 parts.

[0105]

[0106] This application presents a solid waste mining cementitious material based on fly ash, desulfurized gypsum, and carbide slag. Breakthroughs in material performance are achieved through innovative mineralization accelerators and toughening stabilizers.

[0107] 1. Core Innovation: For the first time, a simple-to-synthesize organic-inorganic composite admixture, mineralization accelerator and toughening stabilizer, was introduced into the fly ash, desulfurized gypsum and carbide slag system, which significantly improved CO2 mineralization efficiency and overall material performance.

[0108] 2. Performance advantages: The material has a 3-day strength ≥ 2.0 MPa, a 28-day strength ≥ 8.0 MPa, excellent volume stability (dry shrinkage ≤ 0.08%), and good impermeability and flame retardancy.

[0109] 3. Economic and environmental benefits: Solid waste utilization rate >95%, cost reduction of 40-50% compared to cement, and CO2 mineralization and storage of 60-90 kg per ton of material, providing coal mines with an integrated solution of "solid waste disposal - carbon emission reduction - safe backfilling".

[0110] The cementing material in the embodiments of this application significantly improves the early strength, volume stability and erosion resistance of the filling body, and is particularly suitable for filling goaf areas, roadway support and foundation reinforcement in coal mines.

[0111] In summary, the present invention provides a functional cementing material for solid waste mining, its preparation method, and its application. This cementing material achieves high performance by using an organic mineralization-enhancing additive to realize a triple synergistic mechanism of "alkali activation-sulfate activation-mineralization enhancement," while reducing energy consumption and lowering costs.

[0112] It will be readily understood by those skilled in the art that the above-described advantageous methods can be freely combined and superimposed without conflict. The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application. The above are merely preferred embodiments of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this application, and these improvements and modifications should also be considered within the protection scope of this application.

Claims

1. A functional cementitious material for solid waste mining, characterized in that, The cementing material comprises the following components: a solid waste substrate and an organic mineralization reinforcing additive; wherein the solid waste substrate includes fly ash, desulfurized gypsum, and carbide slag; the organic mineralization reinforcing additive comprises the following components: a mineralization accelerator and a toughening and stabilizing agent; the mineralization accelerator comprises the following components: Sodium acryloyl dimethyl taurate, phytic acid-chitosan polymer, and tridecafluorooctyltriethoxysilane; the toughening and stabilizing agent comprises the following components: cyclodextrin-modified lignin sulfonate, cellulose aerogel microspheres, and triethanolamine borate. The cementing material comprises, by weight, 100 parts of solid waste substrate and 3-6 parts of organic mineralization reinforcing additive; wherein, 1.5-3 parts are mineralization accelerator and 1.5-3 parts are toughening and stabilizing agent.

2. The bonding material according to claim 1, characterized in that, The solid waste substrate also includes steel slag powder or slag powder.

3. The preparation method of the functional cementitious material for solid waste mining according to any one of claims 1-2, characterized in that, include: The solid waste substrate is pretreated to obtain the pretreated solid waste substrate, which includes pulverized fly ash, pulverized desulfurized gypsum and pulverized and aged carbide slag. Preparation of mineralization accelerators and toughening and stabilizing agents; Mineralization accelerators and toughening stabilizers are mixed to form an organic mineralization reinforcing admixture; The ground fly ash, ground desulfurized gypsum and ground and aged carbide slag are mixed to obtain a mixed substrate. The organic mineralization reinforcing additive is added to the mixed substrate in multiple batches for mixing. The organic mineralization enhancement additive is added at intervals of a first preset time, and the total mixing time is greater than or equal to a second preset time.

4. The method according to claim 3, characterized in that, The steps for preparing the mineralization accelerator include: Sodium acryloyl dimethyl taurate was dissolved in deionized water to prepare a first solution with a mass fraction of 20%. Phytic acid-chitosan polymer is added to the first solution under constant stirring to form a first mixture; After adding tridecafluorooctyltriethoxysilane dropwise to the first mixture, the reaction was carried out at 60°C for 2 hours to obtain the reaction solution; The reaction solution was spray-dried to obtain a mineralization accelerator.

5. The method according to claim 3, characterized in that, The steps for preparing the toughening and stabilizing agent include: Calcium lignin sulfate was dissolved in deionized water to prepare a second solution with a mass fraction of 25%. Cellulose aerogel microspheres were added to the second solution and ultrasonically dispersed to obtain a second mixture; After adding triethanolamine borate to the second mixture, the mixture was reacted at 80°C for 1.5 hours to obtain the third mixture; The third mixture is dried and pulverized to obtain a toughening and stabilizing agent.

6. The method according to claim 3, characterized in that, The step of pretreating the solid waste substrate to obtain the pretreated solid waste substrate includes: The calcium carbide slag should be naturally aged for at least seven days to fully dissolve the residual calcium carbide; the aged calcium carbide slag should be ground until the specific surface area is greater than or equal to 350 m². 2 / kg; Fly ash and desulfurized gypsum were ground separately until the residue on an 80μm sieve was ≤10%, thus obtaining ground fly ash and ground desulfurized gypsum respectively.

7. The method according to claim 3, characterized in that, The first preset time is 3 minutes, and the second preset time is greater than or equal to 15 minutes.

8. The application of the functional cementitious material for solid waste mining as described in any one of claims 1-2, characterized in that, Used for filling goaf areas, roadway support, and foundation reinforcement in coal mines.

9. The application according to claim 8, characterized in that, The application method includes: The cementitious material and water are mixed and stirred to obtain a slurry; Carbon dioxide is introduced into the slurry, and the introduction of carbon dioxide is stopped when the pH value of the slurry reaches 12; the slurry after the introduction of carbon dioxide is injected into the target area.

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