High-fluidity, fast-setting, and early-strength cementitious material, as well as its preparation method and application

Abstract

The present invention relates to the technical field of building materials, and in particular to a high-fluidity, fast-setting, and early-strength cementitious material, as well as a preparation method and application thereof. The present invention adopts mineral powder and red mud to prepare modified waste residue powder as the main cementitious material, adds a strengthening component, a retarding cementing component, and a water-reducing component to regulate the setting time, fluidity, and early mechanical properties of the cementitious material, and prepares a cementitious material with high early fluidity, controllable setting time, high early and late strength, good mud resistance, and no dispersion in water. The cementitious material can be used for on-site plugging and rescue of dangerous situations such as dam leakage.

Description

Technical Field

[0001] The present invention relates to the technical field of building materials, in particular to a high-fluidity, fast-setting, and early-strength gelling material, and a preparation method and application thereof. Background Art

[0002] With the continuous development of water conservancy projects, the number of large-scale dams, levees, ditches and other hydraulic structures continues to increase, playing a vital role in resisting natural disasters and flood prevention. When a dam leaks or is foreseeable, facing the challenges of rapid water flow and easily expanded channels in the seepage zone, conventional slurries are easily diluted and dispersed, making them unable to meet the emergency needs of timely plugging. Therefore, for the rapid on-site disposal of dam leakage hazards, emergency repair materials are required to meet the requirements of high fluidity, adjustable setting time, high early strength, strong adaptability, and environmental protection.

[0003] The prior art CN108395126A proposes to use cement clinker, acrylate, phosphogypsum and other raw materials to make leak repair materials, but the use process requires heating, the process is cumbersome, and the slurry solidification time is too long, which is not suitable for on-site rescue. Traditional cementitious materials, especially highly fluid concrete materials, can meet the needs of modern buildings for rapid construction and high early strength, but cement, lime and the like are often accompanied by large amounts of carbon emissions during production and use, which not only aggravates the greenhouse effect, but also has a significant impact on the ecological environment. Therefore, exploring and developing new low-carbon cementitious materials and realizing the green transformation of building materials are extremely important for the development of engineering building materials.

[0004] Alkali-activated materials use a large amount of industrial solid waste and can replace cement as a cementitious material. The existing technology uses slag and alkali activators to make grouting and soil-rock consolidation materials, which set too quickly, and there is a contradiction between high fluidity and rapid setting. The reason is that when the slurry has a high fluidity, the dosage of admixtures such as alkali activators is low, and rapid setting cannot be achieved; when the slurry achieves rapid setting, the dosage of materials such as activators is high, and the slag reacts with materials such as activators very quickly, and high fluidity cannot be guaranteed. Summary of the Invention

[0005] In order to solve the problems existing in the prior art, the present invention provides a high-fluidity, fast-setting and early-strength cementitious material. Specifically, the present invention adopts mineral powder and red mud to prepare modified waste slag powder as the main cementitious material, and realizes the stimulation and carbonization closure of the high-activity sites of the mineral powder through red mud and carbonization process, and adds strengthening components, retarding cementing components and water-reducing components to regulate the setting time, fluidity and early mechanical properties of the cementitious material. The water-reducing agent component and the retarding cementing component realize the large fluidity control of the slurry, the retarding cementing component realizes the setting time control, and improves the supersaturation of ions in the liquid environment. The strengthening components and water glass take effect after the mineral powder gradually dissolves to form a supersaturated ion liquid phase, thereby improving the early strength, and preparing a cementitious material with high early fluidity, controllable setting time, high early and late strength, good mud resistance, and no dispersion in water, which can be used for on-site plugging and rescue of dangerous situations such as dam leakage.

[0006] Specifically, the high-fluidity, fast-setting, and early-strength cementitious material of the present invention is composed of the following raw materials in parts by weight: 80-95 parts of modified waste residue powder, 5-25 parts of a strength-promoting component, 2-15 parts of a retarding cementation component, and 0.05-1 part of a water-reducing component.

[0007] Preferably, the preparation process of the modified waste slag powder is: mixing mineral powder, red mud and water in a mass ratio of 100:(2-5):(30-50) to form a waste slag slurry, uniformly mixing the waste slag slurry with a carbonization accelerator in a mass ratio of 100:(2-25), heating and stirring, adding 2-4% tributyl phosphate by mass of the waste slag slurry, and passing carbon dioxide-containing gas into it for carbonization, filtering, drying, and grinding to obtain the product.

[0008] The present invention first mixes mineral powder, red mud and water to form a waste slurry. The red mud is rich in alkaline components and can significantly increase the pH value of the slurry, thereby stimulating the local dissolution of the reactive area of the high active sites enriched with Ca and Al in the slag powder, completing the pre-stimulation of the high active sites of the mineral powder, thereby facilitating the subsequent carbonization reaction. In the carbonization arrangement, the waste slurry is reacted by introducing a carbon dioxide atmosphere to form carbonate deposition. Since a large amount of active ions are dissolved in the active site area after the mineral powder is stimulated by the red mud, the carbon dioxide preferentially reacts with these ions to generate carbonates, thereby achieving carbonization sealing of the high active sites of the mineral powder. In the carbonization process of the present invention, tributyl phosphate is added as a nucleating agent. The tributyl phosphate absorbs Ca and Al to form carbonates. 2 + , forming high-concentration ion clusters locally and providing a polar environment, which is conducive to promoting Ca 2+ With CO3 2－ Ion binding reduces the free energy required for nucleation, thereby accelerating the nucleation and precipitation process of CaCO3; the mineral components of red mud itself are more stable than mineral powder and have lower reactivity with carbon dioxide. Therefore, the silicon and aluminum substances in red mud basically do not undergo significant carbonization reaction during the carbonization process.

[0009] Preferably, the carbonization accelerator is an organic amine, and more preferably, the carbonization accelerator is at least one of 2-amino-2-methyl-1-propanol, piperazine, 1,3-bis(diethylamino)-2-propanol, triethylenetetramine, and tetraethylenepentamine. Organic amines can increase carbon dioxide absorption and carbonization efficiency, and are known in the art.

[0010] Preferably, the heating and stirring is heating to 40-70° C. and stirring at 60-150 r / min for 1.5-3 h.

[0011] Preferably, the strengthening component is a mixture of sulphoaluminate cement clinker, gypsum and sodium sulfate in a mass ratio of 2:(2-9):(0.5-4).

[0012] Preferably, the gypsum is at least one of desulfurized gypsum, anhydrite, and hemihydrate gypsum.

[0013] Preferably, the slow-gelling component is a mixture of triethanolamine, water glass and sodium hydroxide in a mass ratio of (0.1-0.5):(1-3.5):(0.4-2.5).

[0014] In the present invention, triethanolamine, water glass and sodium hydroxide are added as retarding setting components. Although triethanolamine and water glass are often used as activators in cement-based materials, in the system of the present invention, their combination exhibits an overall retarding effect under a specific mechanism of action. Specifically, the alcoholamine can react with the Ca dissolved in the slurry to form a retarding effect. 2+ Ions undergo complex adsorption, reducing free Ca in the liquid phase 2+ The concentration of water glass can inhibit the supersaturated accumulation rate of hydration products, thereby delaying the initial hydration reaction. Although water glass can provide silicate ions, its effect of stimulating hydration reaction depends largely on the free Ca in the system. 2+ When the alcohol amine complexes Ca 2+ , reduce free Ca 2+ When the concentration is high, the excitation effect of water glass is suppressed, and then a certain retarding effect is synergistically manifested. As the reaction proceeds, the mineral powder continues to dissolve Ca 2+ When the complexing capacity of alcohol amine is close to saturation, free Ca 2+ The concentration begins to rise rapidly, and the abundant silicate ions in the water glass are able to react with Ca 2+ reaction, quickly generating hydration products such as CSH gel, thereby achieving the transition of the system from initial slow setting to rapid early strength. Therefore, in the system of the present invention, the alcoholamine and water glass are controlled by free Ca 2+ The concentration and the rate of hydration product formation work together to achieve the performance control goals of high fluidity in the initial stage, slightly slow setting, and rapid setting and early strength in the later stage.

[0015] Preferably, the water glass modulus is 0.8-1.6.

[0016] Preferably, the water-reducing component is at least one of a polycarboxylate water-reducing agent, calcium lignin sulfonate, and a naphthalene-based water-reducing agent.

[0017] Preferably, the particle size of the modified waste residue powder is ≤45 μm.

[0018] The present invention also relates to a method for preparing the above-mentioned high-fluidity, fast-setting, and early-strength gelling material, which specifically comprises the following steps:

[0019] 1) Weigh each raw material by weight,

[0020] 2) Mix all the raw materials evenly.

[0021] The present invention also relates to the application of the high-fluidity, fast-setting, and early-strength gelling material in emergency repair projects.

[0022] The present invention has the following technical advantages:

[0023] 1. The cementitious material of the present invention has high fluidity and can fill complex or irregular pores without vibration, and has good construction and filling properties.

[0024] 2. The setting time of the cementitious material of the present invention is adjustable, and the early strength is high, which meets the requirements of rapid construction and high early strength.

[0025] 3. The cementitious material of the present invention has excellent mud resistance and can still ensure excellent mechanical properties even when the sand and gravel contain a large amount of mud. It uses a large amount of industrial waste and reduces carbon emissions. DETAILED DESCRIPTION

[0026] In order to characterize the technical effect of the present invention, a cementitious material was prepared and its performance was tested. During the test, 42 parts of cementitious material, 3 parts of soil, 135 parts of standard sand, and a water-cement ratio of 0.35 were used. The carbonization accelerator was piperazine, the water glass modulus was 1.0, and the water-reducing component was a polycarboxylic acid water reducer.

[0027] Example 1

[0028] The cementitious material is composed of the following raw materials in parts by weight: 89 parts of modified waste residue powder, 22 parts of strengthening component, 13 parts of slow-setting component, and 1 part of water-reducing component.

[0029] The preparation process of modified waste slag powder is as follows: mineral powder, red mud and water are mixed in a mass ratio of 100:3:45 to form waste slag slurry, the waste slag slurry is evenly mixed with a carbonization accelerator in a mass ratio of 100:5, the temperature is raised to 65°C, and stirred at 100r / min for 2h, 4% tributyl phosphate by mass of the waste slag slurry is added, and carbon dioxide gas is introduced for carbonization for 1.5h, filtered, dried, and ground to a particle size of ≤45μm to obtain,

[0030] The strengthening component is a mixture of sulphoaluminate cement clinker, anhydrite and sodium sulfate in a mass ratio of 2:9:1.

[0031] The retarding gelling component is a mixture of triethanolamine, water glass and sodium hydroxide in a mass ratio of 0.4:2.5:2.

[0032] After testing, the initial fluidity of the slurry is 310mm, the 5-minute fluidity is 295mm, the initial setting time is 9min, the final setting time is 17min, the 24h compressive strength is 7.5MPa, and the 28d compressive strength is 40.3MPa.

[0033] Example 2

[0034] The cementitious material is composed of the following raw materials in parts by weight: 92 parts of modified waste residue powder, 20 parts of strengthening component, 15 parts of slow-setting component, and 1 part of water-reducing component.

[0035] The preparation process of modified waste slag powder is as follows: mineral powder, red mud and water are mixed in a mass ratio of 100:4:50 to form waste slag slurry, the waste slag slurry is evenly mixed with a carbonization accelerator in a mass ratio of 100:5, the temperature is raised to 60°C, and stirred at 120r / min for 2h, 3% tributyl phosphate by mass of the waste slag slurry is added, and carbon dioxide gas is introduced for carbonization for 2h, filtered, dried, and ground to a particle size of ≤45μm to obtain the modified waste slag powder.

[0036] The strengthening component is a mixture of sulphoaluminate cement clinker, hemihydrate gypsum and sodium sulfate in a mass ratio of 2:7:2.

[0037] The slow-gelling component is a mixture of triethanolamine, water glass and sodium hydroxide in a mass ratio of 0.3:3:1.5.

[0038] After testing, the initial fluidity of the slurry is 300mm, the 5-minute fluidity is 290mm, the initial setting time is 10min, the final setting time is 19min, the 24h compressive strength is 8.9MPa, and the 28d compressive strength is 41.7MPa.

[0039] Comparative Example 1

[0040] The cementitious material is composed of the following raw materials in parts by weight: 89 parts of modified waste residue powder, 22 parts of strengthening component, 13 parts of slow-setting component, and 1 part of water-reducing component.

[0041] The preparation process of modified waste slag powder is as follows: mix mineral powder and red mud in a mass ratio of 100:3, grind to a particle size of ≤45μm, and obtain

[0042] The strengthening component is a mixture of sulphoaluminate cement clinker, anhydrite and sodium sulfate in a mass ratio of 2:9:1.

[0043] The slow-gelling component is a mixture of triethanolamine, water glass and sodium hydroxide in a mass ratio of 0.4:2.5:2.

[0044] After testing, the initial fluidity of the slurry is 280mm, the 5-minute fluidity is 255mm, the initial setting time is 6 minutes, the final setting time is 10 minutes, the 24-hour compressive strength is 5.8MPa, and the 28-day compressive strength is 31.7MPa.

[0045] Comparative Example 2

[0046] The cementitious material is composed of the following raw materials in parts by weight: 89 parts of modified waste residue powder, 22 parts of strengthening component, 13 parts of slow-setting component, and 1 part of water-reducing component.

[0047] The preparation process of modified waste slag powder is as follows: mineral powder, red mud and water are mixed in a mass ratio of 100:3:45 to form waste slag slurry, the waste slag slurry is evenly mixed with a carbonization accelerator in a mass ratio of 100:5, the temperature is raised to 65°C, stirred at 100r / min for 2h, and carbonized for 1.5h by introducing carbon dioxide gas, filtering, drying, and grinding to a particle size of ≤45μm.

[0048] The strengthening component is a mixture of sulphoaluminate cement clinker, anhydrite and sodium sulfate in a mass ratio of 2:9:1.

[0049] The slow-gelling component is a mixture of triethanolamine, water glass and sodium hydroxide in a mass ratio of 0.4:2.5:2.

[0050] After testing, the initial fluidity of the slurry is 290mm, the 5-minute fluidity is 280mm, the initial setting time is 8 minutes, the final setting time is 15 minutes, the 24-hour compressive strength is 6.5MPa, and the 28-day compressive strength is 35.3MPa.

[0051] Comparative Example 3

[0052] The cementitious material is composed of the following raw materials in parts by weight: 89 parts of modified waste residue powder, 22 parts of strengthening component, 13 parts of slow-setting component, and 1 part of water-reducing component.

[0053] The preparation process of modified waste slag powder is as follows: mineral powder, red mud and water are mixed in a mass ratio of 100:3:45 to form waste slag slurry, the waste slag slurry is evenly mixed with a carbonization accelerator in a mass ratio of 100:5, the temperature is raised to 65°C, and stirred at 100r / min for 2h, 4% tributyl phosphate by mass of the waste slag slurry is added, and carbon dioxide gas is introduced for carbonization for 1.5h, filtered, dried, and ground to a particle size of ≤45μm to obtain,

[0054] The strengthening component is a mixture of sulphoaluminate cement clinker, anhydrite and sodium sulfate in a mass ratio of 2:9:1.

[0055] The slow-gelling component is a mixture of sodium gluconate and borax in a mass ratio of 2:1.

[0056] After testing, the initial fluidity of the slurry is 270mm, the 5-minute fluidity is 255mm, the initial setting time is 20min, the final setting time is 34min, the 24h compressive strength is 4.9MPa, and the 28d compressive strength is 33.6MPa.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-fluidity, fast-setting, early-strength gelling material, characterized in that: It is composed of the following raw materials in parts by weight: 80-95 parts of modified waste residue powder, 5-25 parts of strengthening component, 2-15 parts of slow-setting component, 0.05-1 part of water-reducing component, The modified waste slag powder preparation process comprises: mixing mineral powder, red mud and water in a mass ratio of 100:(2-5):(30-50) to form a waste slag slurry, uniformly mixing the waste slag slurry with a carbonization accelerator in a mass ratio of 100:(2-25), heating and stirring, adding 2-4% tributyl phosphate by mass of the waste slag slurry, introducing carbon dioxide-containing gas for carbonization, filtering, drying and grinding to obtain the modified waste slag powder. The strengthening component is a mixture of sulphoaluminate cement clinker, gypsum and sodium sulfate in a mass ratio of 2:(2-9):(0.5-4), The slow-gelling component is a mixture of triethanolamine, water glass and sodium hydroxide in a mass ratio of (0.1-0.5):(1-3.5):(0.4-2.5).

2. The high-fluidity, fast-setting, early-strength cementitious material according to claim 1, characterized in that: The carbonization accelerator is at least one of 2-amino-2-methyl-1-propanol, piperazine, 1,3-di(diethylamino)-2-propanol, triethylenetetramine, and tetraethylenepentamine.

3. The high-fluidity, fast-setting, early-strength cementitious material according to claim 1, characterized in that: The heating and stirring is to heat the mixture to 40-70° C. and stir the mixture at 60-150 r / min for 1.5-3 hours.

4. The high-fluidity, fast-setting, early-strength cementitious material according to claim 3, characterized in that: The gypsum is at least one of desulfurized gypsum, anhydrite and hemihydrate gypsum.

5. The high-fluidity, fast-setting, early-strength cementitious material according to claim 1, characterized in that: The water-reducing component is at least one of a polycarboxylate water-reducing agent, calcium lignin sulfonate, and a naphthalene-based water-reducing agent.

6. The high-fluidity, fast-setting, early-strength cementitious material according to claim 1, characterized in that: The particle size of the modified waste residue powder is ≤45 μm.

7. The method for preparing a high-fluidity, fast-setting, and early-strength cementitious material according to any one of claims 1 to 6, characterized in that: The steps include: 1) Weigh each raw material by weight, 2) Mix all the raw materials evenly.

8. Use of the high-fluidity, fast-setting, and early-strength cementitious material according to any one of claims 1 to 6 in emergency repair projects.