Early-strength and high-strength alkali-free liquid accelerator material based on solid waste and preparation method of early-strength and high-strength alkali-free liquid accelerator material

Abstract

The invention relates to the technical field of building materials, in particular to an early-strength and high-strength alkali-free liquid accelerator material based on solid waste and a preparation method thereof.The early-strength and high-strength alkali-free liquid accelerator material based on solid waste is prepared from, by mass, 10%-20% of industrial solid waste, 30%-50% of inorganic mineral salt, 20%-40% of composite hectorite and 5%-10% of alcohol amine compounds. The invention aims to improve the stability and the coagulation performance of the liquid alkali-free accelerator and greatly increase the mortar strength of the liquid alkali-free accelerator in 6h and 1d by adopting industrial solid wastes, treating the solid wastes and optimizing the formula of the accelerator, thereby solving the problem that the compressive strength of the early high-strength sprayed concrete in 8h is difficult to be greater than or equal to 10MPa. And recycling of industrial solid waste is realized.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, and in particular to an early high-strength alkali-free liquid quick-setting agent material based on solid waste and its preparation method. Background Technology

[0002] Early-strength shotcrete exhibits significantly higher early-stage compressive strength than ordinary shotcrete, reaching over 10 MPa in 8 hours and over 15 MPa in 1 day. This contributes to improved rock mass stability, enabling rapid rock support and enhancing construction efficiency and safety. With advancements in tunnel construction technology, early-strength shotcrete is increasingly required in railway tunnel construction. Accelerators, which rapidly hydrate cement, are crucial materials in shotcrete application. According to relevant national and industry standards, liquid alkali-free accelerators are required for railway construction.

[0003] Currently, liquid alkali-free quick-setting agents on the market are mainly divided into two types: one is a fluorine-containing solution-type alkali-free quick-setting agent, which has good setting performance and low consistency, but low 1-day compressive strength and is not human-friendly, and cannot achieve the early strength requirements of early high-strength shotcrete; the other is a fluorine-free suspension-type alkali-free quick-setting agent, which has high 1-day compressive strength and is human-friendly, but poor setting performance and high consistency, and must be formulated with special admixtures to achieve the early strength requirements of early high-strength shotcrete.

[0004] Blast furnace slag is a solid waste generated during the blast furnace ironmaking process. It is mainly composed of oxides such as CaO, SiO2, Al2O3 and MgO, as well as a small amount of sulfides. Its annual emissions are large and its utilization rate is poor. How to develop the application of blast furnace slag in liquid alkali-free liquid quick-setting agent materials is a research direction for researchers in this field, so as to better realize the reuse of solid waste. Summary of the Invention

[0005] In view of this, the purpose of this invention is to provide an early high-strength alkali-free liquid accelerator material based on solid waste and its preparation method. By using industrial solid waste and treating the solid waste, and by optimizing the formulation of the accelerator, the stability and setting performance of the liquid alkali-free accelerator can be improved, and the 6-hour and 1-day mortar strength of the liquid alkali-free accelerator can be significantly increased. This solves the problem that the 8-hour compressive strength of early high-strength shotcrete is difficult to meet ≥10MPa, and realizes the reuse of industrial solid waste.

[0006] The present invention solves the above-mentioned technical problems through the following technical means:

[0007] A high-strength, alkali-free liquid accelerator material based on solid waste, comprising the following raw materials by mass percentage:

[0008] The composition includes 10-20% industrial solid waste, 30-50% inorganic mineral salts, 20-40% composite lithium saponite, and 5-10% alkanolamine compounds.

[0009] Based on the aforementioned technical methods, by optimizing the formulation of the accelerator using industrial solid waste, inorganic mineral salts, and composite lithium saponite as the main materials, the stability and setting performance of the liquid alkali-free accelerator can be improved. This significantly increases the 6-hour and 1-day mortar strength of the liquid alkali-free accelerator, thereby solving the problem that the 8-hour compressive strength of early high-strength shotcrete is difficult to meet ≥10MPa, and enabling the reuse of industrial solid waste. Furthermore, the use of alkanolamine compounds as auxiliary agents not only improves the suspension performance of the material but also enhances its early strength performance.

[0010] Preferably, the industrial solid waste is one or more of the following: blast furnace slag, carbide slag, coal slag, fly ash, red mud, and gypsum.

[0011] Further preferred industrial solid waste is blast furnace slag.

[0012] Further preferred, the blast furnace slag is expanded slag, and the main chemical composition of expanded slag is CaO, SiO2, Al2O3, MgO, MnO and Fe2O3.

[0013] Based on the above technical means, by selecting expanded blast furnace slag and limiting the main chemical composition of the expanded blast furnace slag, its use in concrete can improve the strength and setting performance of concrete.

[0014] More preferably, the mass percentage of CaO is 32%–38%; the mass percentage of SiO2 is 30%–40%; the mass percentage of Al2O3 is 10%–20%; the mass percentage of MgO is 5%–10%; the mass percentage of MnO is 0.1%–1%; and the mass percentage of Fe2O3 is 0.1%–2%.

[0015] Based on the above-mentioned technical means, by limiting the mass percentage of chemical composition in expanded slag, it is helpful to fill voids and enhance the compactness of concrete, thereby further improving the compressive strength and durability of concrete.

[0016] Preferably, the inorganic mineral salt is one or more of talc, kaolin, wollastonite, mica, and perlite powder.

[0017] Further preferred inorganic mineral salt is talc, with a purity of 90% or higher.

[0018] Based on the above technical means, by using talc powder as a quick-setting agent, it can not only adsorb, disperse, and suspend blast furnace slag powder, but also contain elements such as silicon and magnesium, which can promote cement hydration, thereby improving the stability, setting performance and early strength of the quick-setting agent.

[0019] Preferably, the composite lithium saponite comprises lithium saponite and nano-silica, and the composite lithium saponite is prepared by intercalating lithium saponite and then combining it with nano-silica.

[0020] According to the above-mentioned technical means, by combining nano-silica with lithium saponite, the dispersion performance of lithium saponite in alkali-free quick-setting agents can be improved, agglomeration can be avoided, and the stability and coagulation performance of liquid alkali-free quick-setting agents can be enhanced.

[0021] Preferably, the preparation of the composite lithium saponite includes the following steps: S1. Dispersing lithium saponite in a solvent, ultrasonically treating, centrifuging, washing, and drying to obtain pretreated lithium saponite; S2. Adding nano-silica to a silane coupling agent solution, ultrasonically treating, to obtain a mixed solution; S3. Dispersing the pretreated lithium saponite in water to form a suspension, then adding the mixed solution, stirring continuously at 50-80℃ for 2-5 hours, filtering, washing, and drying to obtain an intermediate.

[0022] S4. Disperse the intermediate in water, add nano-silica, sonicate, centrifuge and dry to obtain composite lithium saponite.

[0023] Based on the aforementioned technical methods, solvent and ultrasonic treatment of lithium saponite can expand the interlayer spacing, which is beneficial for its composite with nano-silica. Then, surface modification of the nano-silica using a silane coupling agent makes the silica surface hydrophobic, facilitating the intercalation of pretreated lithium saponite by the nano-silica. Further intercalation of the surface-modified nano-silica at a higher temperature yields lithium saponite intercalated with nano-silica. This improves the dispersion stability and adsorption performance of lithium saponite in solvents, thereby enhancing its dispersion stability in alkali-free quick-setting agents and forming a stable colloidal system. In particular, it avoids the agglomeration of lithium saponite caused by the acidity of the quick-setting agent due to the formation of aluminum sulfate anions in the alkali-free quick-setting agent. Furthermore, the solution-based intercalation method is simple, low-cost, and suitable for large-scale production.

[0024] Finally, the intermediate formed by intercalating lithium saponite with nano-silica is used to adsorb nano-silica to form composite lithium saponite. This not only further improves the dispersion performance in alkali-free quick-setting agents, but also promotes cement hydration and increases the early strength of concrete after the quick-setting agent is added to concrete due to the introduction of nano-silica. It can also form a stable three-dimensional network structure, thereby enhancing the physical and mechanical properties and durability of early-strength concrete.

[0025] More preferably, in step S1, the solvent is one or more combinations of KH550, KH570, KH792, and KH602.

[0026] A further preferred solvent is KH550.

[0027] Based on the above technical means, the use of silane coupling agent KH550 to perform layer expansion treatment on lithium saponite is simple and will not affect subsequent operations.

[0028] More preferably, in steps S2 and S4, the particle size of the nano-silica is 1-2 nm.

[0029] Based on the above technical means, by selecting 1-2nm silica, it is easier for it to intercalate with lithium saponite, and during adsorption and binding, it can adsorb more and has a stronger binding ability.

[0030] More preferably, in step S3, when the mixed solution is added, the weight ratio of the suspension to the mixed solution is 100:15-48.

[0031] More preferably, the weight ratio of the suspension to the mixed solution is 100:23-30.

[0032] Based on the above technical means, by controlling the addition ratio, sufficient intercalation reaction can be carried out while avoiding excessive waste of nano-silica.

[0033] Preferably, the alkanolamine compound is one or a combination of ethanolamine, diethanolamine, triethanolamine, and diethanol monoisopropanolamine.

[0034] Based on the above-mentioned technical means, by using environmentally friendly alkanolamine compounds, on the one hand, they can play an early strength role in concrete and improve the early strength of the accelerator; on the other hand, they can also reduce the environmental problems caused by the production process.

[0035] This application also discloses a method for preparing an early high-strength alkali-free liquid rapid-setting agent material based on solid waste, including the following steps:

[0036] S10. Add blast furnace slag, talc powder, composite lithium saponite, and alkanolamine to a ball mill and grind for 36-72 hours to obtain powder;

[0037] S20. The ground powder is sieved and cooled to room temperature to obtain an early high-strength alkali-free quick-setting agent material.

[0038] Based on the above technical means, blast furnace slag, talc, lithium saponite, and alkanolamine are ball-milled to obtain nano-sized powder, thereby increasing the specific surface area of ​​the powder and enhancing its physicochemical activity. This is beneficial for the suspension and dispersion of crystals and promotes cement hydration, improving the stability, setting performance, and early strength of the accelerator. At the same time, alkanolamine, as a grinding aid, can improve grinding efficiency and play an early strength role in concrete, which can improve the early strength of the accelerator.

[0039] Preferably, in step S20, the powder is sieved through a 1000-1500 mesh sieve.

[0040] Further preferred, the powder is sieved through a 1200-mesh sieve.

[0041] Using the above-mentioned technical means, particles that do not meet the required size are removed by sieving, thereby improving the quality of the product.

[0042] This application also discloses an alkali-free liquid quick-setting agent, including the aforementioned early high-strength alkali-free liquid quick-setting agent material based on solid waste, and further including aluminum sulfate, diethanolamine and water.

[0043] Based on the above technical means, a liquid alkali-free quick-setting agent is formed by industrial solid waste, inorganic mineral salts, composite lithium saponite, alkanolamine compounds, aluminum sulfate and water. This can improve the stability and setting performance of the liquid alkali-free quick-setting agent, and significantly increase the mortar strength of the liquid alkali-free quick-setting agent at 6 hours and 1 day, thereby solving the problem that the compressive strength of early high-strength shotcrete is difficult to meet ≥10MPa at 8 hours.

[0044] The present application, employing the above-described scheme, has the following beneficial effects:

[0045] 1. In this application, by optimizing the formulation of the accelerator using industrial solid waste, inorganic mineral salts, and composite lithium saponite as the main materials, the stability and setting performance of the liquid alkali-free accelerator can be improved, significantly increasing the 6-hour and 1-day mortar strength of the liquid alkali-free accelerator. This solves the problem that the 8-hour compressive strength of early high-strength shotcrete is difficult to meet ≥10MPa, and also realizes the reuse of industrial solid waste. Furthermore, the use of alkanolamine compounds as auxiliary agents not only improves the suspension properties of the material but also enhances its early strength performance.

[0046] 2. The high-strength, alkali-free accelerator nanomaterials in this application utilize the principle that blast furnace slag, rich in elements such as silicon, lithium, magnesium, aluminum, and iron, can promote cement hydration. Through adsorption, dispersion, and suspension, the accelerator's setting performance and early strength are improved, realizing the utilization of blast furnace slag solid waste. Furthermore, by using composite lithium saponite, the dispersion performance of lithium saponite in the alkali-free accelerator can be improved, avoiding agglomeration and enhancing the stability and setting performance of the liquid alkali-free accelerator. At the same time, the dispersion performance in the alkali-free accelerator can be further improved. Moreover, due to the introduction of nano-silica, the accelerator, when added to concrete, can promote cement hydration, increase the early strength of concrete, and form a stable three-dimensional network structure, thereby enhancing the physical and mechanical properties and durability of early-strength concrete.

[0047] 3. When the high-strength, alkali-free quick-setting agent nanomaterial prepared in this application is used in the production of liquid alkali-free quick-setting agent, it is only necessary to stir the nanomaterial, aluminum sulfate, diethanolamine and water at 35℃~40℃, and after sufficient suspension and dispersion, a fluorine-free alkali-free quick-setting agent that meets national standards can be obtained. The production equipment and process are simple and the production temperature is relatively low.

[0048] 4. When the early high-strength alkali-free quick-setting agent nanomaterial prepared in this application is used in the production of liquid alkali-free quick-setting agent, the dosage is 1% to 3%, which can significantly improve the stability, setting performance and early strength of liquid alkali-free quick-setting agent. After 28 days in a 100mL stoppered graduated cylinder, the supernatant height of the liquid alkali-free quick-setting agent is less than or equal to 2mL, the qualified dosage of the mortar setting time is ≤7%, the compressive strength of mortar at 6h is ≥1.5MPa, the compressive strength of mortar at 1d is ≥15.0MPa, the compressive strength of shotcrete at 8h is ≥10.0MPa, and the compressive strength of shotcrete at 1d is ≥20.0MPa. Attached Figure Description

[0049] This application can be further illustrated by the non-limiting embodiments given in the accompanying drawings;

[0050] Figure 1 This is a schematic diagram of the early high-strength alkali-free liquid quick-setting agent material based on solid waste in the embodiments of this application;

[0051] Figure 2 This is a diagram of the alkali-free liquid quick-setting agent using lithium saponite in the embodiments of this application;

[0052] Figure 3 This is a diagram of an alkali-free liquid quick-setting agent using composite lithium saponite in the embodiments of this application. Detailed Implementation

[0053] The technical solutions of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0054] The following raw materials are used in the embodiments of this application:

[0055] The blast furnace slag, specifically expanded slag, has the following main chemical composition: CaO (32%–38%), SiO2 (30%–40%), Al2O3 (10%–20%), MgO (5%–10%), MnO (0.1%–1%), and Fe2O3 (0.1%–2%).

[0056] Talc powder, whose main chemical component is MgSiO3•H2O, has a purity of 90% or higher;

[0057] Lithium saponite, whose main chemical component is Li2Mg2O9Si3, has a purity of 99% or higher;

[0058] Nano-silica, whose main chemical component is SiO2, has a purity of 99% or higher and a particle size of 1-2 nm;

[0059] Diethanolamine, industrial grade, with a purity of 99% or higher;

[0060] Triethanolamine, industrial grade, with a purity of 99% or higher;

[0061] Examples 1-9: Screening of Early High-Strength Alkali-Free Liquid Accelerator Material Formulations

[0062] In this embodiment, the high-strength, alkali-free, rapid-setting nanomaterial based on the utilization of blast furnace slag solid waste is prepared using the following method:

[0063] S10. Add blast furnace slag, talc powder, lithium saponite, and alkanolamine to a ball mill and grind for 48 hours;

[0064] S20. Pass the ground powder through a 1200-mesh square-hole sieve and cool it to room temperature to obtain high-strength, alkali-free, quick-setting nanomaterials.

[0065] Get as Figure 1 The image shows an early-setting, high-strength, alkali-free, quick-setting liquid nanomaterial. The properties of different compositions of this nanomaterial were compared. The nanomaterial was prepared at 2% concentration, aluminum sulfate at 60%, diethanolamine at 8%, and water at 30% at 40°C. The homogeneity of the quick-setting liquid was observed in 100mL graduated stoppered test tubes at 20°C. Figure 2 As shown, an early high-strength alkali-free quick-setting agent was added at 7% of the cement dosage to determine the initial setting time difference of the cement paste and the mortar strength.

[0066] The test results are shown in Table 1:

[0067] Table 1. Orthogonal experiments and results of liquid accelerators in Examples 1-9

[0068]

[0069] Analysis of the above test results reveals the following:

[0070] Triethanolamine can increase the final setting time, but it has a greater impact on the 6-hour mortar strength; while diethanolamine will prolong the final setting time, but its impact on the 6-hour mortar strength is smaller than that of triethanolamine. Therefore, the combined use of diethanolamine and triethanolamine is more effective in improving the final setting time.

[0071] Blast furnace slag can improve setting time and early strength but affects stability. Talc helps improve stability, but experiments have shown that increasing its dosage thickens the accelerator, making it difficult to use. Therefore, the combined use of blast furnace slag and talc, with controlled dosage, can achieve a synergistic effect, jointly improving setting time, early strength, and stability. Lithium saponite can also improve setting time and early strength. When combined with blast furnace slag and talc, it can further improve these properties. However, increasing the dosage of blast furnace slag, talc, and lithium saponite will increase the viscosity of the accelerator.

[0072] Examples 10-18, Screening of Early High-Strength Alkali-Free Liquid Accelerator Material Formulations (Part Two)

[0073] In this embodiment, the high-strength, alkali-free, rapid-setting nanomaterial based on the utilization of blast furnace slag solid waste is prepared using the following method:

[0074] The preparation of composite lithium saponite includes the following steps:

[0075] S1. Disperse lithium saponite in KH550, sonicate at 350 W for 25 min, centrifuge, wash with deionized water 2-3 times, and dry at 100±2℃ to obtain pretreated lithium saponite; S2. Add 10 parts by weight of nano silica to 13 parts by weight of silane coupling agent and 17 parts by weight of deionized water, sonicate at 350 W for 25 min to obtain a mixed solution; S3. Disperse 35 parts by weight of pretreated lithium saponite in 65 parts by weight of deionized water to form a suspension, add 25 parts by weight of the mixed solution, stir continuously at 50℃ for 3 h, filter, wash with deionized water 3 times, and dry at 100±2℃ to obtain a nano silica-intercalated lithium saponite intermediate;

[0076] S4. Disperse 50 parts by weight of the intermediate in 100 parts by weight of deionized water, add 35 parts by weight of nano-silica, sonicate at 350 W for 25 min, centrifuge, and dry at 100±2℃ to obtain composite lithium soapstone.

[0077] S10. Add blast furnace slag, talc powder, composite lithium saponite, and alkanolamine to a ball mill and grind for 48 hours;

[0078] S20. Pass the ground powder through a 1200-mesh square-hole sieve and cool it to room temperature to obtain high-strength, alkali-free, quick-setting nanomaterials.

[0079] The properties of early-setting, high-strength, alkali-free liquid accelerator nanomaterials with different compositions were compared. The early-setting, high-strength, alkali-free liquid accelerator nanomaterials were prepared with 2% aluminum sulfate, 60% diethanolamine, 8% water, and 30% nanomaterials at 40℃. The homogeneity of the early-setting, high-strength, alkali-free liquid accelerator was observed using 100mL graduated stoppered test tubes at 20℃. Figure 3 As shown, an early high-strength alkali-free quick-setting agent was added at 7% of the cement dosage to determine the initial setting time difference of the cement paste and the mortar strength.

[0080] Based on Examples 1-9, the dosages of blast furnace slag, talc, diethanolamine, and triethanolamine were selected, and tests were conducted using benchmark cement. The results are shown in Table 2.

[0081] Table 2. Orthogonal Experiments and Results of Liquid Accelerators in Examples 10-18

[0082]

[0083] Analysis of the above test results reveals the following:

[0084] 1. By using diethanolamine and triethanolamine in combination, the final setting time can be significantly improved compared to using diethanolamine or triethanolamine alone.

[0085] 2. By employing nano-silica composite lithium saponite, with the same dosage of blast furnace slag and talc, the setting time and early strength can be further improved. The viscosity of the accelerator is reduced, resulting in higher stability. Furthermore, the 6-hour and 1-day mortar strengths are both improved, and the final setting time is significantly increased. This indicates that using composite lithium saponite is more effective than using lithium saponite alone, and the dosage of composite lithium saponite is relatively lower. As the dosage of composite lithium saponite increases, the 6-hour and 1-day mortar strengths also improve, as does the final setting time. Therefore, the following specific implementation method is obtained:

[0086] Example 19, Preparation of Early High-Strength Alkali-Free Accelerating Agent Material

[0087] A high-strength, alkali-free, accelerator material based on the utilization of blast furnace slag solid waste comprises the following components by mass percentage:

[0088] Blast furnace slag 15%, talc powder 40%, composite lithium saponite 37%, diethanolamine 6%, triethanolamine 2%.

[0089] S10. Add blast furnace slag, talc powder, composite lithium saponite, and alkanolamine to a ball mill and grind for 48 hours;

[0090] S20. Pass the ground powder through a 1200-mesh square-hole sieve and cool it to room temperature to obtain high-strength, alkali-free, quick-setting nanomaterials.

[0091] Example 20: Preparation of Early High-Strength Alkali-Free Accelerating Agent Material (Part Two)

[0092] A high-strength, alkali-free, accelerator material based on the utilization of blast furnace slag solid waste comprises the following components by mass percentage:

[0093] Blast furnace slag 15%, talc powder 38%, composite lithium saponite 37%, diethanolamine 8%, triethanolamine 2%.

[0094] S10. Add blast furnace slag, talc powder, composite lithium saponite, and alkanolamine to a ball mill and grind for 48 hours;

[0095] S20. Pass the ground powder through a 1200-mesh square-hole sieve and cool it to room temperature to obtain high-strength, alkali-free, quick-setting nanomaterials.

[0096] Example 21, Preparation of Early High-Strength Alkali-Free Liquid Accelerator Material (Part 3)

[0097] A high-strength, alkali-free, accelerator material based on the utilization of blast furnace slag solid waste comprises the following components by mass percentage:

[0098] Blast furnace slag 18%, talc powder 38%, composite lithium saponite 34%, diethanolamine 8%, triethanolamine 2%.

[0099] S10. Add blast furnace slag, talc powder, composite lithium saponite, and alkanolamine to a ball mill and grind for 48 hours;

[0100] S20. Pass the ground powder through a 1200-mesh square-hole sieve and cool it to room temperature to obtain high-strength, alkali-free, quick-setting nanomaterials.

[0101] Example 22, Preparation of Early High-Strength Alkali-Free Accelerating Agent Material (Part Four)

[0102] A high-strength, alkali-free, accelerator material based on the utilization of blast furnace slag solid waste comprises the following components by mass percentage:

[0103] Blast furnace slag 18%, talc powder 38%, composite lithium saponite 38%, diethanolamine 6%.

[0104] S10. Add blast furnace slag, talc powder, composite lithium saponite, and alkanolamine to a ball mill and grind for 48 hours;

[0105] S20. Pass the ground powder through a 1200-mesh square-hole sieve and cool it to room temperature to obtain high-strength, alkali-free, quick-setting nanomaterials.

[0106] The early high-strength alkali-free accelerator nanomaterials prepared in Examples 19-22 were applied to liquid early high-strength alkali-free accelerators at dosages of 1.5% and 2.5%, respectively. The dosages were: aluminum sulfate 60%, diethanolamine 8%, and water 30%. The early high-strength alkali-free accelerators were prepared at 40°C. Ordinary alkali-free accelerators were used as blank samples. Consistency tests were conducted using a Forte-4 leak cup test. Setting performance and strength tests used ordinary Portland cement (Linzhi Gaozheng brand) for the Sichuan-Tibet Railway project and ordinary Portland cement (low alkali) (Neijiang Xingchuancheng brand) for the Chengdu-Chongqing Central Line Railway. The accelerator dosage was 7% of the cementitious material. The test methods followed the enterprise standard QC-R 807-2020 "Liquid Alkali-Free Accelerator for Tunnel Shotcrete" of China State Railway Group Co., Ltd. The concrete mix proportions are shown in Table 3, and the test results are shown in Table 4.

[0107] Table 3. Mix Proportions for Early High-Strength Shotcrete

[0108]

[0109] Table 4 Performance effects of the alkali-free quick-setting agents prepared using Examples 19-22

[0110]

[0111] As shown in Table 4, the early high-strength alkali-free accelerators prepared in Examples 19-22 have an alkali content of ≤1% as required by the standard. They exhibit good compatibility with low-alkali cement and function as suspension, dispersion, and early-strength accelerators, improving the stability and setting performance of liquid alkali-free accelerators. When added to different silicate cements, they significantly increase the 6-hour and 1-day mortar strength of the cement, achieving an 8-hour shotcrete compressive strength ≥10.0 MPa and a 1-day shotcrete compressive strength ≥20.0 MPa, meeting the requirements for tunnel concrete. This solves the problem of early high-strength shotcrete failing to achieve an 8-hour compressive strength ≥10 MPa and a 1-day compressive strength ≥15 MPa, while also enabling the utilization of blast furnace slag solid waste.

[0112] The foregoing has provided a detailed description of an early-setting, high-strength, alkali-free liquid accelerator material based on solid waste and its preparation method, as provided by the present invention. The specific embodiments are provided only to aid in understanding the method and core ideas of the present invention. It should be noted that those skilled in the art can make various improvements and modifications to the present invention without departing from its principles, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0113] It should be noted that: for experimental steps or conditions not specified in the examples, the procedures and conditions described in conventional experimental procedures in the literature of this art can be followed. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0114] The above examples are provided to better understand the present invention and are not limited to the preferred embodiments described. They do not constitute a limitation on the content and scope of protection of the present invention. Any product that is the same as or similar to the present invention, derived by anyone under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the scope of protection of the present invention.

Claims

1. A high-strength, alkali-free liquid quick-setting agent material based on solid waste, characterized in that, Including the following percentages of raw materials by weight: The composition includes 10-20% industrial solid waste, 30-50% inorganic mineral salts, 20-40% composite lithium saponite, and 5-10% alkanolamine compounds.

2. The alkali-free liquid quick-setting agent material according to claim 1, characterized in that, The industrial solid waste is one or more of the following: blast furnace slag, carbide slag, coal slag, fly ash, red mud, and gypsum.

3. The alkali-free liquid quick-setting agent material according to claim 1, characterized in that, The inorganic mineral salt is one or more of the following: talc, kaolin, wollastonite, mica, and perlite powder.

4. The alkali-free liquid quick-setting agent material according to claim 3, characterized in that, The industrial solid waste is blast furnace slag.

5. The alkali-free liquid quick-setting agent material according to claim 1, characterized in that, The inorganic mineral salt is one or more of the following: talc, kaolin, wollastonite, mica, and perlite powder.

6. The alkali-free liquid quick-setting agent material according to claim 1, 2, 3, or 5, characterized in that, The composite lithium saponite comprises lithium saponite and nano-silica. The composite lithium saponite is prepared by intercalating lithium saponite and then combining it with nano-silica.

7. The alkali-free liquid quick-setting agent material according to claim 6, characterized in that, The preparation of the composite lithium saponite includes the following steps: S1. Disperse lithium saponite in a solvent, sonicate, centrifuge, wash, and dry to obtain pretreated lithium saponite; S2. Add nano-silica to a silane coupling agent solution and sonicate to obtain a mixed solution; S3. Disperse the pretreated lithium saponite in water to form a suspension, then add the mixed solution, and stir continuously at 50-80℃ for 2-5 hours. Filter, wash, and dry to obtain the intermediate. S4. Disperse the intermediate in water, add nano-silica, sonicate, centrifuge and dry to obtain composite lithium saponite.

8. The alkali-free liquid quick-setting agent material according to claim 7, characterized in that, In step S1, the solvent is one or more combinations of KH550, KH570, KH792, and KH602.

9. The alkali-free liquid quick-setting agent material according to claim 1, characterized in that, The alkanolamine compound is one or a combination of ethanolamine, diethanolamine, triethanolamine, and diethanol monoisopropanolamine.

10. A method for preparing an early-setting, high-strength, alkali-free liquid accelerator material based on solid waste as described in any one of claims 1-9, characterized in that, Includes the following steps: S10. Add blast furnace slag, talc powder, composite lithium saponite, and alkanolamine to a ball mill and grind for 36-72 hours to obtain powder; S20. The ground powder is sieved and cooled to room temperature to obtain an early high-strength alkali-free quick-setting agent material.

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