Super-early-strength all-solid waste cementing material and preparation method thereof

Abstract

The invention relates to the technical field of building material preparation, and particularly discloses a super-early-strength all-solid waste cementing material and a preparation method thereof. The gelling material comprises the following components in parts by weight: 10-15 parts of an AFt heterogeneous nucleation admixture, 0.03-0.1 part of an ion diffusion agent, 0.5-1.2 parts of an exciting agent, 0.3-1 part of a nitrate and / or nitrite type AFt stabilizer, 70-80 parts of a solid waste based gelling component, 10-15 parts of waste gypsum and a certain amount of mixing water. Wherein the ion diffusion agent contains functional groups-NH and-OH. The AFt heterogeneous nucleation admixture is prepared by the following method: curing and curing neat paste formed by a sulphoaluminate cement binding material, and then crushing and grinding the obtained solid to obtain the AFt heterogeneous nucleation admixture. Through cooperation of the AFt heterogeneous nucleation admixture and other components, the all-solid waste cementing material has good early strength and later strength.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of building material preparation, and particularly relates to a super-early-strength full-solid-waste cementitious material and a preparation method thereof. BACKGROUND

[0002] The information disclosed in this Background section is only for the purpose of increasing an understanding of the general background of the application and does not necessarily constitute an admission by the patent applicant or the patent owner that this information constitutes prior art.

[0003] The production of full-solid-waste cementitious material has become an ideal substitute for ordinary Portland cement due to its low energy consumption, low carbon emissions, and high resource utilization rate. However, most solid waste cementitious materials have slow early hydration, long setting time, and low early strength, which makes it difficult to meet the needs of engineering. This is because under low pH conditions, the hydration reaction of the cementitious component is slow, and the hydration product AFt is less, which makes it difficult to support high early strength.

[0004] Currently, the early strength of full-solid-waste cementitious material is usually improved by adding Portland cement clinker, lime, and other alkaline substances such as carbide slag, but the alkalinity is too high, which affects the development of later strength. This is because in the environment of too high pH, the AFt produced by the hydration reaction of the cementitious component deposits on the surface of the cementitious component, inhibiting its further hydration, and the uneven stress produced by the expansion of the surface AFt will cause microcracks in the interior of the cementitious system. These microcracks are not only weak points in strength, but also provide a channel for the invasion of harmful ions and water, leading to the deterioration of the later strength of the cementitious material. In summary, the traditional way of improving alkalinity leads to the problem that the early and later strength of full-solid-waste cementitious material is difficult to balance, which limits the large-scale application of full-solid-waste cementitious material. SUMMARY

[0005] In view of the above problems, the present application provides a super-early-strength full-solid-waste cementitious material and a preparation method thereof, which makes the cementitious material have good early and later strength through the cooperation between AFt heterogeneous nucleation admixture and other components. Specifically, the technical solution of the present application is as follows.

[0006] Firstly, the application discloses an ultra-early-strength full-solid-waste cementing material, which comprises the following components: 10-15 parts by weight of AFt heterogeneous nucleation admixture, 0.03-0.1 part by weight of an ion diffusion agent, 0.5-1.2 parts by weight of an activator, 0.3-1 part by weight of an AFt stabilizer in the form of a nitrate and / or nitrite, 70-80 parts by weight of a solid-waste-based cementing component, 10-15 parts by weight of waste gypsum, and a certain amount of mixing water.

[0007] Further, the ion diffusion agent comprises at least one of diethanol mono-isopropanolamine (DEIPA), tri-isopropanolamine (TIPA), triethanolamine (TEA) and the like.

[0008] Further, the activator comprises a mixture of calcium formate and an alkaline component. Alternatively, the mass ratio of the calcium formate to the alkaline component is 1:2-2.5, and the alkaline component has a pH value of 12-13. The HCOO - can promote the formation of a hydration product C-(A)-S-H gel, and is adsorbed on the surface of the C-(A)-S-H gel and the solid-waste-based cementing component, so as to avoid the accumulation of the hydration product on the surface of the particles, thereby promoting the hydration of the solid-waste-based cementing component. Meanwhile, the inert glass structure in the solid-waste-based cementing component is accelerated to dissolve and release Ca 2+ , Al 3+ under the excitation of the alkaline component, so as to promote the combination of the ion diffusion agent with Ca 2+ , Al 3+ , accelerate the formation of ettringite along with the rapid diffusion of the ion diffusion agent in the cementing material, and thus improve the early strength of the full-solid-waste cementing material.

[0009] Further, the alkaline component comprises at least one of a sodium hydroxide solution, a potassium hydroxide solution and the like.

[0010] Further, the AFt stabilizer comprises at least one of sodium nitrite, calcium nitrite and calcium nitrate.

[0011] Further, the solid-waste-based cementing component comprises at least one of granulated blast furnace slag powder and the like. Preferably, the content of aluminum oxide in the solid-waste-based cementing component is 13-18 wt.%, so as to ensure the good hydration reactivity of the solid-waste-based cementing component.

[0012] Further, the waste gypsum comprises at least one of fluorite gypsum, phosphorite gypsum, titanium gypsum, etc. Such gypsum has a slow dissolution rate and a relatively larger solubility, thereby continuously providing sulfate, helping to provide conditions for the hydration reaction of the solid waste-based cementitious component, and promoting the hydration degree thereof.

[0013] Further, the mass ratio of the mixing water to the solid waste-based cementitious component is 0.4-0.5:1.

[0014] Further, the net paste is formed by mixing the sulphoaluminate cementitious material and water at a water-cement ratio of 0.4-0.5.

[0015] Further, the sulphoaluminate cementitious material is formed by sulphoaluminate cement clinker and gypsum. Optionally, the ratio of the sulphoaluminate cement clinker to the gypsum is 70-75 parts by weight: 25-30 parts by weight.

[0016] Further, the relative humidity of the curing is 95±5%, the temperature is 20±2℃, and the curing time is 60-75 hours.

[0017] Secondly, the application discloses a preparation method of the super-early-strength full-solid-waste cementitious material, comprising the following steps: (1) After mixing the AFt heterogeneous nucleation admixture, the solid waste-based cementitious component, and the waste gypsum, grinding treatment is performed to obtain activated powder, which is ready for use.

[0018] (2) The ion diffusion agent is added into the mixing water and stirred until fully dissolved, then the AFt stabilizer is added and stirred until fully dissolved, and finally the activator is added and stirred until fully dissolved, to obtain a mixed solution ready for use.

[0019] (3) After mixing the mixed solution and the activated powder, uniform stirring is performed, and the super-early-strength full-solid-waste cementitious material is obtained.

[0020] Compared with the prior art, the technical scheme of the application has at least the following beneficial effects: 1. The cementitious material of the application is mixed with the AFt heterogeneous nucleation admixture, on the one hand, the ettringite crystal seeds in the AFt heterogeneous nucleation admixture induce Ca 2+ , Al 3+ and SO4 2-The rapid formation of a large amount of ettringite in the pore solution between the cementitious material particles effectively overcomes the problem of hindering further dissolution and hydration of the solid waste-based cementitious component, solves the problem of easy precipitation of the ettringite on the surface of the solid waste-based cementitious component in an alkaline environment, and enables the cementitious material of the present application to obtain good early strength. On the other hand, the AFt heterogeneous nucleation admixture contains calcium hydroxide formed during curing and dicalcium silicate that has not been hydrated in time due to slow hydration, so that the calcium hydroxide can be used to provide alkalinity to the system to ensure the hydration of the solid waste-based cementitious component in the early stage, and the dicalcium silicate can be used to continuously release calcium hydroxide to maintain the stability and persistence of alkalinity in the system in the middle and late stages, ensuring that the solid waste-based cementitious component can be fully hydrated to obtain good early, middle and late strength.

[0021] 2、The cementitious material of the present application uses the amine group (-NH2) and hydroxyl group (-OH) contained in the ion diffusion agent to complex and stimulate the dissolution of Ca 2+ , Al 3+ in the solid waste-based cementitious component to form a soluble complex, reduce the diffusion resistance of Ca 2+ , Al 3+ , accelerate its diffusion rate, and rapidly react with SO4 2- released from the waste gypsum under the induction of ettringite seeds in the AFt heterogeneous nucleation admixture to quickly generate a large amount of ettringite in the pore solution, achieving super-early strength performance.

[0022] 3、The cementitious material of the present application uses the AFt stabilizer containing NO2 - or NO3 - to overcome the problem of instability of a large amount of ettringite generated in the system. This is because the NO2 - , NO3 - can react with active alumina in the solid waste-based cementitious component to form stable AFm of nitrite or nitrate type, which alleviates the problem of active alumina competing for SO4²⁻ in the ettringite to cause its decomposition and affect the strength of the cementitious material when gypsum is insufficient due to the large consumption of gypsum in the early stage of hydration. BRIEF DESCRIPTION OF DRAWINGS

[0023] The drawings accompanying the specification of the present application serve to provide a further understanding of the present application, and the illustrative embodiments of the present application and their descriptions serve to explain the present application and do not constitute an improper limitation on the present application.

[0024] Figure 1 Sample chart of the AFt heterogeneous nucleation admixture prepared for the following Example 1.

[0025] Figure 2 XRD test pattern of AFt heterogeneous nucleation blend prepared for Example 1 below.

[0026] Figure 3 SEM test pattern of AFt heterogeneous nucleation blend prepared for Example 1 below.

[0027] Figure 4 28d compressive strength test pattern for Example 1 below.

[0028] Figure 5 Sample pattern of AFt heterogeneous nucleation blend prepared for Example 2 below.

[0029] Figure 6 28d compressive strength test pattern for Example 2 below.

[0030] Figure 7 Sample pattern of AFt heterogeneous nucleation blend prepared for Example 3 below.

[0031] Figure 8 28d compressive strength test pattern for Example 3 below.

[0032] Figure 9 28d compressive strength test pattern for Example 4 below.

[0033] Figure 10 28d compressive strength test pattern for Example 5 below.

[0034] Figure 11 28d compressive strength test pattern for Example 6 below.

[0035] Figure 12 28d compressive strength test pattern for Example 7 below.

[0036] Figure 13 28d compressive strength test pattern for Example 8 below. DETAILED DESCRIPTION

[0037] The application will be further described with reference to the following examples. It should be appreciated that these examples are intended for illustration only and are not intended to limit the scope of the present application. Unless otherwise indicated, the experimental procedures in the following examples were carried out in accordance with conventional procedures or as otherwise described herein.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The materials used to practice the application were obtained from commercial sources unless otherwise indicated. Unless otherwise specified, the materials used to practice the application were used as received or as otherwise described herein.

[0039] Furthermore, any method and material similar or equivalent to those described can be used in the present method. The technical solutions of the present application are further described in conjunction with the accompanying drawings and specific embodiments.

[0040] Example 1: A method for preparing a super-early-strength full-solid-waste cementitious material, comprising the following steps: (1) uniformly mixing sulphoaluminate cement clinker and gypsum powder in a proportion of 75 parts by weight: 25 parts by weight to form a sulphoaluminate cementitious material, then mixing the sulphoaluminate cementitious material with water in a water-cement ratio of 0.43, and stirring uniformly, and curing the obtained neat paste in a curing box (relative humidity controlled at 95±5%, temperature controlled at 20±2℃) for 72 hours. After completion, the obtained solid is crushed, ground, and then passed through a 200-mesh sieve to obtain an AFt heterogeneous nucleation admixture as shown in Figure 1 , and the XRD and SEM detection results thereof are shown in Figure 2 and Figure 3 , respectively.

[0041] (2) taking the following proportions of components: 12 parts by weight of the AFt heterogeneous nucleation admixture of the present embodiment, 0.06 parts by weight of an ion diffusion agent (diethanol mono-isopropanolamine (DEIPA)), 0.9 parts by weight of an activator (formed by calcium formate and a sodium hydroxide solution with pH=12 in a mass ratio of 1:2), 0.55 parts by weight of an AFt stabilizer (sodium nitrite), 76 parts by weight of a solid-waste-based cementitious component (granulated blast furnace slag powder with an alumina content of 15.33wt.% and a specific surface area of 367.4m 2 / kg), 13 parts by weight of waste gypsum (fluorogypsum), and 34.2 parts by weight of mixing water.

[0042] (3) mixing the AFt heterogeneous nucleation admixture, the solid-waste-based cementitious component, and the waste gypsum, and grinding for 30 minutes to obtain activated powder, for standby use.

[0043] (4) adding the ion diffusion agent to the mixing water, and continuously stirring at a speed of 300 rpm for 10 minutes, then adding the AFt stabilizer and continuing to stir for 5 minutes. The activator is loaded into a constant-pressure dropping funnel, and gradually added to the mixture obtained in the foregoing step at a rate of 4 drops per second, while continuously stirring at a speed of 600 rpm, and after the addition is completed, continuing to stir for 10 minutes to obtain a mixture for standby use.

[0044] (5) mixing the mixture with the activated powder and stirring for 2 minutes to obtain a cementitious material.

[0045] Performance test: the cementitious material prepared in this example was cast into a mold, demolded after hardening, and then cured to an age of 3d, 7d, and 28d, respectively, and the compressive strength of the obtained test piece was tested (the test was based on "Cement Mortar Strength Test Method (ISO Method)" (GBT 17671-2021)), and the results are shown in the following table, Figure 4 The 28d compressive strength test diagram of this example is as follows: .

[0046] Example 2: A preparation method of a super-early-strength full-solid-waste cementitious material, comprising the following steps: (1) uniformly mix sulphoaluminate cement clinker and gypsum powder in a proportion of 70 parts by weight: 30 parts by weight to form a sulphoaluminate cementitious material, then mix it with water in a water-cement ratio of 0.4 and stir uniformly, and then place the obtained neat paste in a curing box (relative humidity is controlled at 95±5%, and temperature is controlled at 20±2℃) for 60 hours. After completion, the obtained solid is crushed, ground, and then passed through a 300-mesh sieve in sequence to obtain an AFt heterogeneous nucleation admixture (as shown in Figure 5 ), which is ready for use.

[0047] (2) take the following proportions of components: 10 parts by weight of the AFt heterogeneous nucleation admixture of this example, 0.03 parts by weight of an ion diffusion agent (triisopropanolamine (TIPA)), 0.5 parts by weight of an activator (formed by calcium formate and a sodium hydroxide solution with pH=12.5 in a mass ratio of 1:2.3), 0.3 parts by weight of an AFt stabilizer (calcium nitrate), 70 parts by weight of a solid-waste-based cementitious component (granulated blast furnace slag powder with an alumina content of 13.06wt.% and a specific surface area of 391.7m 2 / kg), 10 parts by weight of waste gypsum (phosphogypsum), and 28 parts by weight of mixing water.

[0048] (3) mix the AFt heterogeneous nucleation admixture, the solid-waste-based cementitious component, and the waste gypsum, and then grind for 30min to obtain an activated powder, which is ready for use.

[0049] (4) add the ion diffusion agent to the mixing water and continuously stir at a speed of 350rpm for 8min, then add the AFt stabilizer and continue to stir for 5min. The activator is loaded into a constant-pressure dropping funnel and gradually added to the mixture obtained in the preceding step at a rate of 5 drops per second, while continuously stirring at a speed of 700rpm, and after the addition is completed, continue to stir for 10min to obtain a mixture, which is ready for use.

[0050] (5) mix the mixture with the activated powder and stir for 2min to obtain a cementitious material.

[0051] Performance testing: The compressive strength (e.g., ) of the cementitious material prepared in this embodiment at different ages was tested using the same method as in Example 1 above. Figure 6 The image shown is a diagram of the 28-day compressive strength test. The results are shown in the table below: .

[0052] Example 3: A method for preparing an ultra-early-strength all-solid waste cementitious material, comprising the following steps: (1) Sulfoaluminate cement clinker and gypsum powder are mixed evenly at a ratio of 72 parts by weight: 28 parts by weight to form sulfoaluminate cement cementitious material. Then, it is mixed with clean water at a water-cement ratio of 0.5 and stirred evenly. The resulting neat slurry is cured in a curing chamber (relative humidity controlled between 95±5% and temperature controlled between 20±2℃) for 75 hours. After completion, the obtained solid material is crushed and ground in sequence, and then passed through a 250-mesh sieve to obtain AFt heterogeneous nucleating admixture (such as...). Figure 7 (As shown), for later use.

[0053] (2) The following components are taken in the following proportions: 15 parts by weight of AFt heterogeneous nucleating admixture in this embodiment, 0.1 parts by weight of ion diffusing agent (triethanolamine (TEA)), 1.2 parts by weight of activator (formed by calcium formate and potassium hydroxide solution at pH=13 in a mass ratio of 1:2.5), 1.0 parts by weight of AFt stabilizer (calcium nitrite), and solid waste-based cementing component (granulated blast furnace slag powder with an alumina content of 17.97 wt.% and a specific surface area of ​​326.9 m²). 2 80 parts by weight of waste gypsum (phosphogypsum) and 40 parts by weight of mixing water.

[0054] (3) The AFt heterogeneous nucleating admixture, solid waste-based cementitious component and waste gypsum are mixed and ground for 35 minutes to obtain activated powder for later use.

[0055] (4) Add the ion diffuser to the mixing water and stir continuously at a rate of 350 rpm for 8 min, then add the AFt stabilizer and continue stirring for 5 min. Put the activator into a constant pressure dropping funnel and gradually add it to the mixture obtained in the previous step at a rate of 5 drops / second, while stirring continuously at a rate of 700 rpm. After the addition is complete, continue stirring for 10 min to obtain a mixture for later use.

[0056] (5) Mix the mixture with the activated powder and stir for 2 minutes to obtain the gelling material.

[0057] Performance testing: The compressive strength (e.g., ) of the cementitious material prepared in this embodiment at different ages was tested using the same method as in Example 1 above. Figure 8 The image shown is a diagram of the 28-day compressive strength test. The results are shown in the table below: .

[0058] Example 4: A method for preparing a super-early-strength full-solid-waste cementitious material, comprising the following steps: (1) Take the following proportions of components: an ionic diffusion agent (diethanol mono-isopropanolamine (DEIPA)) 0.06 parts by weight, an activator (formed from calcium formate and a sodium hydroxide solution with pH = 12 at a mass ratio of 1:2) 0.9 parts by weight, an AFt stabilizer (sodium nitrite) 0.55 parts by weight, a solid-waste-based cementitious component (granulated blast furnace slag powder with an alumina content of 15.33 wt.% and a specific surface area of 367.4 m 2 / kg) 76 parts by weight, waste gypsum (fluorogypsum) 13 parts by weight, and mixing water 34.2 parts by weight.

[0059] (2) Mix the solid-waste-based cementitious component and the waste gypsum, and then grind for 30 min to obtain an activated powder, which is ready for use.

[0060] (3) Add the ionic diffusion agent to the mixing water, and continuously stir at a speed of 300 rpm for 10 min, then add the AFt stabilizer and continue stirring for 5 min. Put the activator into a constant-pressure dropping funnel, and gradually add it to the mixture obtained in the preceding step at a rate of 4 drops per second while continuously stirring at a speed of 600 rpm. After the addition is complete, continue stirring for 10 min to obtain a mixture, which is ready for use.

[0061] (4) Mix the mixture obtained in the preceding step with the activated powder, and stir for 2 min to obtain a cementitious material.

[0062] Performance test: The compressive strength of the cementitious material prepared in this example at different ages was tested using the same method as in Example 1 above (the 28d compressive strength test is shown in FIG. 1), and the results are shown in the following table: Figure 9 .

[0063] Example 5: A method for preparing a super-early-strength full-solid-waste cementitious material, comprising the following steps: (1) Take the following proportions of components: the AFt heterogeneous nucleation admixture prepared in Example 2 above 10 parts by weight, an activator (formed from calcium formate and a sodium hydroxide solution with pH = 12.5 at a mass ratio of 1:2.3) 0.5 parts by weight, an AFt stabilizer (calcium nitrate) 0.3 parts by weight, a solid-waste-based cementitious component (granulated blast furnace slag powder with an alumina content of 13.06 wt.% and a specific surface area of 391.7 m 2 / kg) 70 parts by weight, waste gypsum (phosphogypsum) 10 parts by weight, and mixing water 28 parts by weight.

[0064] ​(2) The AFt heterogeneous nucleation admixture, solid waste-based cementitious component, and waste gypsum are mixed and ground for 30 minutes to obtain an activated powder, which is ready for use.

[0065] (3) The AFt stabilizer is added to the mixing water and stirred at a speed of 350 rpm for 5 minutes. The activator is loaded into a constant pressure dropping funnel and gradually added to the mixture obtained in the previous step at a rate of 5 drops per second while continuously stirring at a speed of 700 rpm. After the addition is complete, the stirring is continued for 10 minutes to obtain a mixture, which is ready for use.

[0066] (4) The mixture is mixed with the activated powder and stirred for 2 minutes to obtain a cementitious material.

[0067] Performance test: The compressive strength of the cementitious material prepared in this example at different ages is tested by the same method as in Example 1 (e.g., as shown in the 28-day compressive strength test graph), and the results are shown in the following table: Figure 10 .

[0068] Example 6: A method for preparing an ultra-early-strength fully solid waste cementitious material, comprising the following steps: (1) Take the following proportions of components: 15 parts by weight of the AFt heterogeneous nucleation admixture prepared in Example 3 above, 0.1 parts by weight of an ion diffusion agent (triethanolamine (TEA)), 1.2 parts by weight of an activator (formed from calcium formate and a potassium hydroxide solution with a pH of 13 at a mass ratio of 1:2.5), 80 parts by weight of a solid waste-based cementitious component (granulated blast furnace slag powder with an alumina content of 17.97 wt.% and a specific surface area of 326.9 m 2 / kg), 15 parts by weight of waste gypsum (phosphogypsum), and 40 parts by weight of mixing water.

[0069] (2) The AFt heterogeneous nucleation admixture, solid waste-based cementitious component, and waste gypsum are mixed and ground for 35 minutes to obtain an activated powder, which is ready for use.

[0070] (3) The ion diffusion agent is added to the mixing water and stirred at a speed of 350 rpm for 8 minutes. Then the activator is loaded into a constant pressure dropping funnel and gradually added to the mixture obtained in the previous step at a rate of 5 drops per second while continuously stirring at a speed of 700 rpm. After the addition is complete, the stirring is continued for 10 minutes to obtain a mixture, which is ready for use.

[0071] (4) The mixture is mixed with the activated powder and stirred for 2 minutes to obtain a cementitious material.

[0072] Performance test: The compressive strength of the cementitious material prepared in this example at different ages is tested by the same method as in Example 1 (e.g., as shown in the 28-day compressive strength test graph), and the results are shown in the following table:​Figure 11 The results are shown in the following table: .

[0073] Example 7: A preparation method of a super-early-strength full-solid-waste cementitious material, comprising the following steps: (1) uniformly mixing sulphoaluminate cement clinker and gypsum powder in a proportion of 70 parts by weight: 30 parts by weight to form sulphoaluminate cementitious material, for standby.

[0074] (2) taking components in the following proportions: 10 parts by weight of sulphoaluminate cementitious material prepared in this embodiment, 0.03 parts by weight of ion diffusion agent (triisopropanolamine (TIPA)), 0.5 parts by weight of activator (formed by calcium formate and sodium hydroxide solution with pH = 12.5 in a mass ratio of 1:2.3), 0.3 parts by weight of AFt stabilizer (calcium nitrate), 70 parts by weight of solid-waste-based cementitious component (granulated blast furnace slag powder with an alumina content of 13.06wt.% and a specific surface area of 391.7m 2 / kg), 10 parts by weight of waste gypsum (phosphogypsum), and 28 parts by weight of mixing water.

[0075] (3) mixing the sulphoaluminate cementitious material, solid-waste-based cementitious component, and waste gypsum, and then grinding for 30 min to obtain activated powder, for standby.

[0076] (4) adding the ion diffusion agent to the mixing water, continuously stirring at a speed of 350 rpm for 8 min, and then adding the AFt stabilizer and continuously stirring for 5 min. The activator is loaded into a constant-pressure dropping funnel and gradually added to the mixture obtained in the foregoing step at a rate of 5 drops per second, while continuously stirring at a speed of 700 rpm, and after the addition is completed, continuously stirring for 10 min to obtain a mixture, for standby.

[0077] (5) mixing the mixture with the activated powder and stirring for 2 min to obtain the cementitious material.

[0078] Performance test: The compressive strength of the cementitious material prepared in this embodiment at different ages is tested by the same method as in Example 1 above (as shown in the 28d compressive strength test chart), and the results are shown in the following table: Figure 12 .

[0079] Example 8: A preparation method of a super-early-strength full-solid-waste cementitious material, comprising the following steps: ​(1) Take the following proportions of components: 12 parts by weight of the AFt heterogeneous nucleation admixture prepared in Example 1 above, 0.06 parts by weight of an ion diffusion agent (diethanol mono-isopropanolamine (DEIPA)), 0.9 parts by weight of an activator (sodium hydroxide solution with pH = 12), 0.55 parts by weight of an AFt stabilizer (sodium nitrite), 76 parts by weight of a solid waste-based cementitious component (granulated blast furnace slag powder with an alumina content of 15.33 wt.% and a specific surface area of 367.4 m 2 / kg), 13 parts by weight of waste gypsum (fluorogypsum), and 34.2 parts by weight of mixing water.

[0080] (2) After mixing the AFt heterogeneous nucleation admixture, the solid waste-based cementitious component, and the waste gypsum, grind and treat for 30 min to obtain an activated powder, which is ready for use.

[0081] (3) Add the ion diffusion agent to the mixing water and continuously stir at a speed of 300 rpm for 10 min, then add the AFt stabilizer and continue stirring for 5 min. Load the activator into a constant-pressure dropping funnel and gradually add it to the mixture obtained in the previous step at a rate of 4 drops per second while continuously stirring at a speed of 600 rpm. After the addition is complete, continue stirring for 10 min to obtain a mixture, which is ready for use.

[0082] (4) After mixing the mixture with the activated powder, stir for 2 min to obtain a cementitious material.

[0083] Performance test: The compressive strength of the cementitious material prepared in this example at different ages was tested using the same method as in Example 1 above (as shown in Figure 28d compressive strength test chart), and the results are shown in the following table: Figure 13 .

[0084] The above only describes preferred embodiments of the present application and is not intended to limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent replacements to some technical features. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.​

Claims

1. An ultra-early-strength all-solid waste cementitious material, characterized in that, The mixture comprises the following components: 10-15 parts by weight of AFt heterogeneous nucleating admixture, 0.03-0.1 parts by weight of ion diffusing agent, 0.5-1.2 parts by weight of activator, 0.3-1 parts by weight of nitrate and / or nitrite type AFt stabilizer, 70-80 parts by weight of solid waste-based cementitious component, 10-15 parts by weight of waste gypsum, and a certain amount of mixing water; wherein: the ion diffusing agent contains functional groups -NH2 and -OH; the AFt heterogeneous nucleating admixture is prepared by the following method: the slurry formed by sulfoaluminate cementitious material is cured and solidified, and the resulting solid is crushed and ground to obtain the final product.

2. The ultra-early-strength all-solid waste cementitious material according to claim 1, characterized in that, The ion diffuser includes at least one of diethanol monoisopropanolamine, triisopropanolamine, and triethanolamine.

3. The ultra-early-strength all-solid waste cementitious material according to claim 1, characterized in that, The activator comprises a mixture of calcium formate and an alkaline component; Alternatively, the mass ratio of calcium formate to alkaline component is 1:2 to 2.5, and the pH of alkaline component is 12 to 13.

4. The ultra-early-strength all-solid waste cementitious material according to claim 3, characterized in that, The alkaline component includes at least one of sodium hydroxide solution and potassium hydroxide solution.

5. The ultra-early-strength all-solid waste cementitious material according to claim 1, characterized in that, The AFt stabilizer includes at least one of sodium nitrite, calcium nitrate, and calcium nitrite.

6. The ultra-early-strength all-solid waste cementitious material according to claim 1, characterized in that, The solid waste-based cementitious component includes granulated blast furnace slag powder; Alternatively, the alumina content in the solid waste-based cementitious component is 13-18 wt.%; Alternatively, the waste gypsum may include at least one of fluorogypsum, phosphogypsum, and titanium gypsum.

7. The ultra-early-strength all-solid waste cementitious material according to claim 1, characterized in that, The mass ratio of the mixing water to the solid waste-based cementitious component is 0.4~0.5:

1.

8. The ultra-early-strength all-solid waste cementitious material according to any one of claims 1-7, characterized in that, The mortar is made by mixing sulfoaluminate cementitious material with water at a water-cement ratio of 0.4 to 0.

5.

9. The ultra-early-strength all-solid waste cementitious material according to any one of claims 1-7, characterized in that, The sulfoaluminate cementitious material is formed from sulfoaluminate cement clinker and gypsum. Alternatively, the ratio of the sulfoaluminate cement clinker to gypsum is 70-75 parts by weight: 25-30 parts by weight; Alternatively, the relative humidity for curing is 95±5%, the temperature is 20±2℃, and the curing time is 60~75 hours.

10. The preparation method of the ultra-early strength all-solid waste cementitious material according to any one of claims 1-9, characterized in that, Includes the following steps: (1) The AFt heterogeneous nucleating admixture, solid waste-based cementitious component and waste gypsum are mixed and then ground to obtain activated powder for later use; (2) Add the ion diffuser to the mixing water and stir until fully dissolved, then add the AFt stabilizer and stir until fully dissolved, and finally add the activator and stir until fully dissolved to obtain a mixture for later use; (3) Mix the mixture with the activated powder and stir evenly to obtain the ultra-early strength all-solid waste cementitious material.

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