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

Abstract

The invention discloses an all-solid waste mining functional cementing material, and a preparation method and application thereof, the cementing material realizes high performance by using an organic mineralization enhancement admixture to realize an alkali activation-sulfate activation-mineralization enhancement triple cooperation mechanism, and at the same time, the energy consumption is reduced, and the cost is low.

Description

Technical Field

[0001] The present invention relates to the technical field of solid waste resource utilization, and in particular to a functional cementing material for all-solid waste mining, a preparation method and an application thereof. Background Art

[0002] Coal mining produces a large amount of fly ash (FA), desulfurized gypsum (FGD) and carbide slag (CCR), the storage of which occupies land and pollutes the environment. Using these solid wastes to prepare mining cementitious materials is a key way to achieve 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 1.0MPa, which is difficult to meet the requirements of rapid underground support; 2. Poor volume stability: The solid waste components are complex and prone to shrinkage and cracking, affecting the density and contact rate of the filling body; 3. Weak erosion resistance: Under long-term erosion by mine water (especially sulfate-containing), the strength is easily degraded; 4. Low mineralization efficiency: The active calcium components in the solid waste (such as Ca(OH)2) react slowly with CO2, and the natural mineralization effect is limited.

[0003] Existing improvement methods mostly focus on mechanical activation or the addition of Portland cement clinker, but the former is energy-intensive, while the latter deviates from the "all-solid-waste" concept. Therefore, how to reduce energy consumption and save costs while maintaining the performance of the cementitious material has become a pressing technical challenge for those skilled in the art. Summary of the Invention

[0004] The embodiments of the present application provide a functional cementitious material for all-solid waste mining, a preparation method and an application thereof. The cementitious material achieves high performance by using an organic mineralization enhancing admixture to realize a triple synergistic mechanism of "alkali excitation-sulfate excitation-mineralization enhancement", while reducing energy consumption and having low cost.

[0005] In a first aspect, the present invention provides a functional cementitious material for all-solid waste mining, the cementitious material comprising the following components: an all-solid waste substrate and an organic mineralization enhancing admixture; wherein the all-solid waste substrate comprises fly ash, desulfurized gypsum and carbide slag; the organic mineralization enhancing admixture comprises the following components: a mineralization promoter and a toughening stabilizer; the mineralization promoter comprises the following components: sodium acryloyldimethyltaurate, phytic acid-chitosan polymer and tridecafluorooctyltriethoxysilane; the toughening stabilizer comprises the following components: cyclodextrin modified lignin sulfonate, cellulose aerogel microspheres and triethanolamine borate.

[0006] In some embodiments, the components of the cementitious material include, by mass, 100 parts of all-solid waste substrate and 3-6 parts of organic mineralization enhancing admixture; among them, 1.5-3 parts of mineralization promoter and 1.5-3 parts of toughening stabilizer.

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

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

[0009] Pre-treating the solid waste substrate to obtain a pre-treated solid waste substrate, wherein the pre-treated solid waste substrate includes ground fly ash, ground desulfurized gypsum, and ground and aged carbide slag;

[0010] Preparation of mineralization accelerators and toughening stabilizers;

[0011] Mixing a mineralization accelerator and a toughening stabilizer to form an organic mineralization reinforcing admixture;

[0012] The ground fly ash, the ground desulfurization gypsum and the ground and aged carbide slag are mixed to obtain a mixed base material, and the organic mineralization enhancement admixture is added to the mixed base material in multiple times for mixing; each addition of the organic mineralization enhancement admixture is separated by 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 comprises:

[0014] Dissolving sodium acryloyldimethyltaurate in deionized water to prepare a first solution with a mass fraction of 20%;

[0015] adding phytic acid-chitosan polymer to the first solution which is continuously stirred to form a first mixture;

[0016] adding tridecafluorooctyltriethoxysilane dropwise to the first mixture, and reacting at 60° C. for 2 hours to obtain a reaction solution;

[0017] The reaction solution is spray-dried to obtain a mineralization promoter.

[0018] In some embodiments, the step of preparing the toughening stabilizer comprises:

[0019] Dissolving lignin calcium sulfate in deionized water to prepare a second solution with a mass fraction of 25%;

[0020] adding cellulose aerogel microspheres to the second solution and performing ultrasonic dispersion to obtain a second mixture;

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

[0022] The third mixture is dried and crushed to obtain a toughening stabilizer.

[0023] In some embodiments, the step of pre-treating the solid waste substrate to obtain a pre-treated solid waste substrate comprises:

[0024] The carbide slag is naturally aged for at least seven days to allow the residual carbide to be fully digested; the aged carbide slag is ground to a specific surface area greater than or equal to 350m 2 / kg;

[0025] The fly ash and desulfurized gypsum are ground respectively to an 80 μm sieve residue of ≤10%, thereby obtaining ground fly ash and ground desulfurized gypsum.

[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] In a third aspect, the present invention provides an application of a functional cementing material for all-solid waste mining, which is characterized in that it is used for filling goaf areas, supporting tunnels and reinforcing foundations in underground coal mines.

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

[0029] Mixing and stirring the cementitious material and water 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] The present invention provides a functional cementing material for all-solid waste mining, a preparation method and an application thereof. The cementing material achieves high performance by using an organic mineralization enhancing admixture to realize a triple synergistic mechanism of "alkali excitation-sulfate excitation-mineralization enhancement", while reducing energy consumption and having low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A flow chart of a method for preparing a functional cementitious material for all-solid waste mining according to some embodiments is exemplified. DETAILED DESCRIPTION

[0033] In order to better understand the above technical solution, the technical solution of this application is described in detail below through specific implementation methods.

[0034] Coal mining produces a large amount of fly ash, desulfurization gypsum and calcium carbide slag, the storage of which occupies land and pollutes the environment. Using these solid wastes to prepare mining cementitious materials is a key way to achieve 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 1.0MPa, which is difficult to meet the requirements of rapid underground support; 2. Poor volume stability: The solid waste components are complex and prone to shrinkage and cracking, affecting the density and connection rate of the filling body; 3. Weak erosion resistance: Under long-term erosion by mine water (especially sulfate-containing), the strength is easily degraded; 4. Low mineralization efficiency: The active calcium components in the solid waste (such as Ca(OH)2) react slowly with CO2, and the natural mineralization effect is limited.

[0035] Existing improvement methods mostly focus on mechanical activation or the addition of Portland cement clinker, but the former is energy-intensive, while the latter deviates from the "all-solid-waste" concept. Therefore, how to reduce energy consumption and save costs while maintaining the performance of the cementitious material has become a pressing technical challenge for those skilled in the art.

[0036] In order to solve the above technical problems, the embodiments of the present application provide a functional cementing material for all-solid waste mining, a preparation method and an application. The cementing material achieves high performance by using an organic mineralization enhancing admixture to realize the triple synergistic mechanism of "alkali excitation-sulfate excitation-mineralization enhancement", while reducing energy consumption and having low cost.

[0037] In an embodiment of the present application, a functional cementitious material for all-solid waste mining is provided, and the cementitious material includes the following components: an all-solid waste substrate and an organic mineralization enhancing admixture; wherein the all-solid waste substrate includes fly ash, desulfurized gypsum and carbide slag; the organic mineralization enhancing admixture includes the following components: a mineralization promoter and a toughening stabilizer; the mineralization promoter includes the following components: sodium acryloyldimethyltaurate, phytic acid-chitosan polymer and tridecafluorooctyltriethoxysilane; the toughening stabilizer includes the following components: cyclodextrin modified lignin sulfonate, cellulose aerogel microspheres and triethanolamine borate.

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

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

[0040] 2. Sulfate excitation: Desulfurization 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. Mineralization enhancement: The sulfonic acid group of sodium acryloyldimethyltaurate chelates with the active Al2O3 in fly ash, promoting the dissolution of carbide slag (Ca(OH)2) and releasing Ca 2+ At the same time, the phytic acid-chitosan polymer guides the directional crystallization of nano-calcium carbonate generated by mineralization through the phosphate group, and the hydrophobic effect of tridecafluorooctylsilane reduces the water evaporation channel. The three work together to form a dense hydration product network, which improves the early strength. Cyclodextrin modified lignin sulfonate absorbs SO4 in desulfurized gypsum through the β-ring cavity 2- Delaying coagulation, and the B(OH)4 produced by the hydrolysis of triethanolamine borate - With Ca 2+ Dynamic [BO-Ca] cross-linking bonds are formed, and cellulose aerogel microspheres serve as nano-reinforced skeletons, jointly constructing a "slow-setting-reinforcement" dual effect, thereby improving the 28-day strength.

[0042] 4. Synergistic effect: The alkaline environment provided by carbide slag activates the silicon-aluminum phase in fly ash, and the SO3 of desulfurized gypsum and the phosphorus groups of phytic acid-chitosan synergistically generate ettringite (AFt) and aluminophosphate (CAPH). The aerogel microspheres form an organic-inorganic hybrid high-strength structure through interlayer ion exchange, which significantly improves the compressive strength.

[0043] In some embodiments, the components of the cementitious material include, by mass, 100 parts of all-solid waste substrate and 3-6 parts of organic mineralization enhancing admixture; among them, 1.5-3 parts of mineralization promoter and 1.5-3 parts of toughening stabilizer.

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

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

[0046] In the embodiments of the present application, the activity of steel slag powder and slag powder is higher than that of fly ash, and the addition of some steel slag powder or slag powder plays a role in improving the early strength.

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

[0048] The present application also provides a method for preparing a functional cementing material for all-solid waste mining. Figure 1 A flowchart of a method for preparing a functional cementitious material for all-solid waste mining according to some embodiments is shown. The method includes steps S100 to S500.

[0049] S100: pre-treating the solid waste substrate to obtain a pre-treated solid waste substrate.

[0050] In some embodiments, the step of pre-treating the solid waste substrate to obtain a pre-treated solid waste substrate comprises:

[0051] The carbide slag is naturally aged for at least seven days to allow the residual carbide to be fully digested; the aged carbide slag is ground to a specific surface area greater than or equal to 350m 2 / kg;

[0052] The fly ash and desulfurized gypsum are ground respectively to an 80 μm sieve residue of ≤10%, thereby obtaining ground fly ash and ground desulfurized gypsum.

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

[0054] S200: preparing a mineralization accelerator.

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

[0056] Dissolving sodium acryloyldimethyltaurate in deionized water to prepare a first solution with a mass fraction of 20%;

[0057] A phytic acid-chitosan polymer is added to the continuously stirred first solution to form a first mixture; wherein the phytic acid-chitosan polymer is self-assembled from bio-based phytic acid and chitosan in a mass ratio of 2:1. In one example, the first solution is continuously stirred at a speed of 1000 revolutions per minute.

[0058] adding tridecafluorooctyltriethoxysilane dropwise to the first mixture, and reacting at 60° C. for 2 hours to obtain a reaction solution;

[0059] The reaction solution is spray-dried to obtain a mineralization promoter.

[0060] In one example, 100g of sodium acryloyldimethyltaurate (Mw ≈ 3000) was dissolved in 500ml of deionized water to prepare a 20% first solution. To this stirred first solution, 15g of phytic acid-chitosan polymer was added dropwise, followed by 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 the embodiment of the present application, the sulfonic acid group of sodium acryloyldimethyltaurate chelates with the active Al2O3 in fly ash, promoting the dissolution of carbide slag (Ca(OH)2) and releasing Ca 2+ The phosphate groups in the phytic acid-chitosan polymer guide the directional crystallization of the mineralized nano-calcium carbonate. The hydrophobic effect of tridecafluorooctylsilane reduces water evaporation channels. The three synergistically form a dense network of hydration products, improving 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-carbonized layer at high temperatures, which has a flame retardant effect.

[0062] S300, prepare toughening stabilizer.

[0063] In some embodiments, the step of preparing the toughening stabilizer comprises:

[0064] Dissolving lignin calcium sulfate in deionized water to prepare a second solution with a mass fraction of 25%;

[0065] adding cellulose aerogel microspheres to the second solution and performing ultrasonic dispersion to obtain a second mixture;

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

[0067] The third mixture is dried and crushed to obtain a toughening stabilizer.

[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 was added, and ultrasonic dispersion was performed 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 stabilizer.

[0069] In the embodiment of the present application, cyclodextrin modified lignin sulfonate absorbs SO4 in desulfurized gypsum through the β-ring cavity. 2- Delaying coagulation, and the B(OH)4 produced by the hydrolysis of triethanolamine borate - With Ca 2+Dynamic [BO-Ca] cross-linking bonds are formed, and cellulose aerogel microspheres serve as nano-reinforced skeletons, jointly constructing a "slow-setting-reinforcement" dual effect, thereby improving the 28-day strength.

[0070] In some embodiments, a method for preparing cellulose aerogel microspheres includes the following: 1. Solution Preparation: 1.1 Coagulation Bath Preparation: Prepare a 5% CaCl2 aqueous solution (or anhydrous ethanol) as a coagulation bath and allow to stand for later use. 1.2 Cellulose Solution Preparation: Dissolve 7g of NaOH and 12g of urea in 81g of deionized water precooled to -15°C and stir to dissolve. Add 4g of microcrystalline cellulose (MCC) and continue stirring for 30 minutes until a transparent, viscous solution forms. 2. Hydrogel Sphere Formation: 2.1 Titration: Aspirate the cellulose solution into a syringe. From a height of 5–10cm, drip it into the coagulation bath at a constant rate (1–2 drops / second) to form gel microspheres with a diameter of 1–3mm. 2.2 Gel Curing: Allow the microspheres to stand in the coagulation bath for ≥30 minutes to complete curing. 2.3 Solvent Replacement: Rinse the gel spheres three times with deionized water and then soak them in anhydrous ethanol for 12 hours. 3. Freeze drying and post-processing: 3.1 Freeze drying: Dry in a freeze dryer (-50℃, ≤10Pa) for 24–48 hours to obtain white porous cellulose aerogel microspheres.

[0071] S400, mixing the mineralization accelerator and the toughening stabilizer to form an organic mineralization reinforcing admixture.

[0072] S500, mixing the ground fly ash, the ground desulfurization gypsum and the ground and aged carbide slag to obtain a mixed base material, adding the organic mineralization enhancing admixture into the mixed base material in multiple times for mixing; wherein each addition of the organic mineralization enhancing admixture is separated by a first preset time, and the total mixing time is greater than or equal to a second preset time.

[0073] In the embodiments of the present application, the total mixing time includes the time for mixing to obtain the mixed base material and the sum of the mixing time after adding the organic mineralization enhancing admixture.

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

[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 sealed and packaged after passing the inspection.

[0077] The embodiment of the present application also provides an application of a functional cementing material for all-solid waste mining, which is used for filling goaf areas, supporting tunnels and reinforcing foundations in coal mines.

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

[0079] Mixing and stirring the cementitious material and water 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 an embodiment of the present application, the binder material and water are mixed and stirred to obtain a slurry, and then the pH of the slurry is controlled to 12 by using carbon dioxide or flue gas carbon dioxide with a concentration greater than 0 and less than or equal to 100%, and the introduction of carbon dioxide is stopped. The slurry introduced with carbon dioxide is then injected into the target area.

[0082] Example 1:

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

[0084] The organic mineralization reinforcing admixture includes 2.0 parts of a mineralization accelerator and 2.0 parts of a toughening stabilizer.

[0085] Pre-treating the solid waste substrate to obtain a pre-treated solid waste substrate, wherein the pre-treated solid waste substrate includes ground fly ash, ground desulfurized gypsum, and ground and aged carbide slag; mixing a mineralization accelerator and a toughening stabilizer to form an organic mineralization enhancing admixture;

[0086] After dry-mixing ground fly ash, ground desulfurized gypsum, and ground, aged carbide slag for 12 minutes, an organic mineralization enhancement admixture was added in three batches, with a three-minute interval between each addition, for a total mixing time of 18 minutes. The cementitious materials were mixed with water at a water-cement ratio of 0.45 to create a slurry. CO₂ was introduced into the slurry to control its pH to 12, after which the CO₂ addition was stopped. The slurry, which had been injected with CO₂, was then injected into the target area with a mortar-sand ratio of 1:4 (standard sand).

[0087] Example 2:

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

[0089] The organic mineralization reinforcing admixture includes 2.5 parts of mineralization accelerator and 1.5 parts of toughening stabilizer.

[0090] Example 3:

[0091] The difference from Example 1 is that the all-solid waste substrate includes 55 parts of fly ash, 25 parts of desulfurization gypsum and 20 parts of carbide slag.

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

[0093] Example 4:

[0094] The difference from Example 1 is that the all-solid waste substrate includes 40 parts of fly ash, 20 parts of desulfurization gypsum, 35 parts of carbide slag and 5 parts of slag powder.

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

[0096] Example 5:

[0097] The difference from Example 1 is that the all-solid waste substrate includes 60 parts of fly ash, 15 parts of desulfurization gypsum and 25 parts of carbide slag.

[0098] The organic mineralization reinforcing admixture includes 1.5 parts of a mineralization accelerator and 1.5 parts of a toughening stabilizer.

[0099] Comparative Example 1:

[0100] The difference from Example 1 is that 100 parts of pure cement base is used to replace 100 parts of the solid waste base material, and the cement base is P·O42.5 cement.

[0101] Comparative Example 2:

[0102] The difference from Example 1 is that no organic mineralization enhancing admixture is used.

[0103] Comparative Example 3:

[0104] The difference from Example 1 is that only a mineralization accelerator is used without a toughening stabilizer, wherein the fraction of the mineralization accelerator is 4 parts.

[0105]

[0106] In the examples of this application, a fully solid waste mining cementing material with fly ash, desulfurized gypsum, and carbide slag as the core was developed. A breakthrough in material performance was achieved through innovative mineralization accelerators and toughening stabilizers:

[0107] 1. Core innovation: For the first time, a simple synthetic organic-inorganic composite admixture mineralization promoter and toughening stabilizer was introduced into the fly ash, desulfurization gypsum, and carbide slag system, significantly improving the CO2 mineralization efficiency and overall material performance.

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

[0109] 3. Economic and environmentally friendly: Solid waste utilization rate is >95%, and the cost is 40-50% lower than cement. Each ton of material can mineralize and store 60-90kg of CO2, providing coal mines with an integrated solution of "solid waste disposal - carbon emission reduction - safe filling".

[0110] The binder material in the embodiment of the present application significantly improves the early strength, volume stability and corrosion resistance of the filling body, and is particularly suitable for filling goaf areas, tunnel support and foundation reinforcement in coal mines.

[0111] In summary, the present invention provides a functional binder material for all-solid waste mining, a preparation method and an application. The binder material achieves high performance by using an organic mineralization enhancing admixture to realize a triple synergistic mechanism of "alkali excitation-sulfate excitation-mineralization enhancement", while reducing energy consumption and having low cost.

[0112] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed. The above is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application. The above is only a preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application. These improvements and variations should also be regarded as the scope of protection of the present application.

Claims

1. A functional cementing material for all-solid waste mining, characterized in that: The cementitious material comprises the following components: a full solid waste base material and an organic mineralization enhancing admixture; wherein the full solid waste base material comprises fly ash, desulfurized gypsum and carbide slag; the organic mineralization enhancing admixture comprises the following components: a mineralization accelerator and a toughening stabilizer; the mineralization accelerator comprises the following components: Sodium acryloyldimethyltaurate, phytic acid-chitosan polymer and tridecafluorooctyltriethoxysilane; the toughening stabilizer comprises the following components: cyclodextrin modified lignin sulfonate, cellulose aerogel microspheres and triethanolamine borate.

2. The bonding material according to claim 1, characterized in that The components of the cementitious material include, by mass, 100 parts of all-solid waste base material and 3-6 parts of organic mineralization enhancing admixture; among them, 1.5-3 parts of mineralization accelerator and 1.5-3 parts of toughening stabilizer.

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

4. The method for preparing the functional cementing material for all-solid waste mining according to any one of claims 1 to 3, characterized in that: include: Pre-treating the solid waste substrate to obtain a pre-treated solid waste substrate, wherein the pre-treated solid waste substrate includes ground fly ash, ground desulfurized gypsum, and ground and aged carbide slag; Preparation of mineralization accelerators and toughening stabilizers; Mixing a mineralization accelerator and a toughening stabilizer to form an organic mineralization reinforcing admixture; Mixing the ground fly ash, the ground desulfurized gypsum and the ground and aged carbide slag to obtain a mixed base material, and adding the organic mineralization enhancing admixture to the mixed base material in multiple batches for mixing; Each addition of the organic mineralization enhancement admixture is separated by a first preset time, and the total mixing time is greater than or equal to a second preset time.

5. The method according to claim 4, characterized in that The steps of preparing the mineralization accelerator include: Dissolving sodium acryloyldimethyltaurate in deionized water to prepare a first solution with a mass fraction of 20%; adding phytic acid-chitosan polymer to the first solution which is continuously stirred to form a first mixture; adding tridecafluorooctyltriethoxysilane dropwise to the first mixture, and reacting at 60° C. for 2 hours to obtain a reaction solution; The reaction solution is spray-dried to obtain a mineralization promoter.

6. The method according to claim 4, characterized in that The steps of preparing the toughening stabilizer include: Dissolving lignin calcium sulfate in deionized water to prepare a second solution with a mass fraction of 25%; adding cellulose aerogel microspheres to the second solution and performing ultrasonic dispersion to obtain a second mixture; After adding triethanolamine borate to the second mixture, reacting at 80° C. for 1.5 hours to obtain a third mixture; The third mixture is dried and crushed to obtain a toughening stabilizer.

7. The method according to claim 4, characterized in that The step of pre-treating the solid waste substrate to obtain the pre-treated solid waste substrate comprises: The carbide slag is naturally aged for at least seven days to allow the residual carbide to be fully digested; the aged carbide slag is ground to a specific surface area greater than or equal to 350m 2 / kg; The fly ash and desulfurized gypsum are ground respectively to an 80 μm sieve residue of ≤10%, thereby obtaining ground fly ash and ground desulfurized gypsum.

8. The method according to claim 4, characterized in that The first preset time is 3 minutes, and the second preset time is greater than or equal to 15 minutes.

9. The use of the functional cementing material for all-solid waste mining according to any one of claims 1 to 3, characterized in that: Used for filling goaf in coal mines, supporting tunnels and reinforcing foundations.

10. The use according to claim 9, characterized in that The method of application includes: Mixing and stirring the cementitious material and water 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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