A fast-setting type alkali-activated low calcium silico-aluminate composite cement without high-temperature curing and a preparation method thereof

Abstract

The application discloses a fast-setting type alkali-activated low calcium silico-aluminate composite cement without high-temperature maintenance and a preparation method thereof, and relates to the field of building materials.The composite cement comprises main components and function-regulating components, wherein the main components are measured according to the following mass percentage: (1) low calcium silico-aluminate raw material 60-75%, (2) alkali-activated raw material 25-40%, and the sum of the two is 100%. In addition, the function-regulating components are additionally added according to the mass of the low calcium silico-aluminate raw material in the main components being 100%, and the dosages of the components are as follows: (1) super dispersant 2-8%, (2) solubilizer 5-10%, and (3) coagulant 1-10%. The preparation steps comprise: ① raw material grinding and ② mixing. The application avoids the high-temperature maintenance process during preparation of the alkali-activated low calcium silico-aluminate composite cement, realizes the synergistic development of setting and hardening and mechanical properties at room temperature, and has a wide application prospect.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of building materials, and particularly relates to a preparation method of fast-setting alkali-activated low-calcium silico-aluminate composite cement without high-temperature curing. BACKGROUND

[0002] The alkali-activated silico-aluminate composite cement is prepared by using silico-aluminate materials as raw materials and through the depolymerization-polymerization reaction of minerals in the silico-aluminate materials under the action of alkali-activated raw materials, and has a three-dimensional network structure matrix. The material has excellent properties such as high strength, high-temperature resistance, acid and alkali corrosion resistance, and heavy metal solidification, and has wide application prospects in the fields of fire prevention and heat insulation, building, heavy metal solidification, and nuclear waste sealing.

[0003] At present, the common representative alkali-activated silico-aluminate composite cement mainly includes alkali-activated high-calcium silico-aluminate composite cement represented by alkali-activated slag and alkali-activated low-calcium silico-aluminate composite cement represented by alkali-activated fly ash. However, the setting and hardening of the alkali-activated low-calcium silico-aluminate composite cement under room temperature conditions is very slow, and high-temperature activation is often required, which leads to problems such as increased carbon emission, high preparation energy consumption, and high cost.

[0004] Therefore, effective regulation and control of the setting and hardening of the alkali-activated low-calcium silico-aluminate composite cement under room temperature conditions, and reduction of the preparation energy consumption and cost of the alkali-activated low-calcium silico-aluminate composite cement are of great significance for the popularization and application of the alkali-activated low-calcium silico-aluminate composite cement. SUMMARY

[0005] In view of the above problems, the application provides a preparation method of fast-setting alkali-activated low-calcium silico-aluminate composite cement without high-temperature curing. In the application, low-calcium silico-aluminate materials are used as raw materials, and through the mutual synergistic effect between the functional regulation components, the dispersion degree of the low-calcium silico-aluminate raw materials can be greatly improved, the dissolution rate and solubility thereof can be increased, the amount of the cementitious product can be increased, and the setting and hardening rate of the matrix can be accelerated, so as to solve the problem of slow development of the setting and hardening performance and mechanical properties of the alkali-activated low-calcium silico-aluminate composite cement under room temperature conditions. The specific content of the application is as follows:

[0006] The preparation method of the fast-setting alkali-activated low-calcium silico-aluminate composite cement without high-temperature curing comprises the following steps: mixing low-calcium silico-aluminate raw materials and alkali-activated raw materials to obtain a mixture; and adding functional regulation components to the mixture to obtain the fast-setting alkali-activated low-calcium silico-aluminate composite cement without high-temperature curing.

[0007] The low calcium silicate alumina raw material in the main component is one or two of fly ash, coal gangue, red mud, lithium residue, and the content of CaO in the chemical composition of the low calcium silicate alumina raw material is less than 8%, and the sum of the contents of SiO2 and Al2O3 is greater than 30%.

[0008] The alkaline excitation raw material in the main component is one or two of tetrabutylammonium hydroxide, methyltriethylammonium hydroxide, hexamethonium hydroxide, and benzyltrimethylammonium hydroxide.

[0009] The hyperdispersant in the functional regulation component is one or two of pyridine propane sulfonic acid and octadecylamine acetate.

[0010] The solubilizing agent in the functional regulation component is one or two of sodium secondary alkyl sulfonate, sodium octyl sulfonate, and polyoxyethylene sorbitan fatty acid ester.

[0011] The coagulant in the functional regulation component is one or two of calcium citrate, calcium threonate, and calcium polyphosphate.

[0012] The fast-setting alkali-activated low calcium silicate alumina composite cement without high-temperature curing has the following preparation steps:

[0013] ① Raw material grinding: the low calcium silicate alumina raw material in the main component is placed in a ball mill according to the mass percentage, and the surface area of the obtained powder is controlled at 300m 2 / kg-500m 2 / kg.

[0014] ② Mixing: the powder obtained in step ① is placed in a mixer, and the alkaline excitation raw material is added first and mixed and stirred for 30 min according to the mass percentage; then the functional regulation component is additionally added, and the addition sequence is: first add the hyperdispersant and stir for 15 min, then add the solubilizing agent and stir for 15 min, and finally add the coagulant and continue to stir for 30 min, to obtain the fast-setting alkali-activated low calcium silicate alumina composite cement without high-temperature curing.

[0015] The technical features of the present application are that: compared with the alkaline excitation raw material used in the existing alkali-activated silico-aluminate composite cement, the present application innovatively uses organic alkali to replace inorganic alkali as the alkaline excitation raw material. At the same time, in view of the problem that the setting and hardening performance and mechanical properties of the alkali-activated low-calcium silico-aluminate composite cement under room temperature conditions develop slowly, on the basis of the action of the alkaline excitation raw material, the present application uses the synergistic effect of the functional regulation components to realize the synergistic rapid development of the setting and hardening and mechanical properties of the alkali-activated low-calcium silico-aluminate composite cement under room temperature conditions. The alkali-activated low-calcium silico-aluminate composite cement prepared by the present application does not need high-temperature curing, and its final setting time can be regulated to about 1.5 hours under room temperature conditions, the 3-day compressive strength can reach 30.5 MPa, and the 28-day compressive strength can reach 74.6 MPa. Specifically, the synergistic regulation mechanism of the functional regulation components on the performance of the alkali-activated low-calcium silico-aluminate composite cement is as follows: the super dispersant can form multi-point anchoring on the surface of the low-calcium silico-aluminate raw material, greatly improve the dispersion degree of particles in the slurry after contacting with water, increase the contact area of the alkaline excitation raw material and the low-calcium silico-aluminate raw material, and improve the dissolution rate of the low-calcium silico-aluminate raw material. Further, the used solubilizer can form micellar groups composed of small colloidal ions in the slurry. Due to the difference in dielectric constant between the inside and the surrounding of the alkali-activated low-calcium silico-aluminate composite cement slurry, the low-solubility minerals in the low-calcium silico-aluminate raw material interact with the micellar groups in different ways according to their own chemical properties, so that the low-solubility minerals are dispersed in the micellar groups, thereby increasing the dissolution amount of the low-calcium silico-aluminate raw material, releasing more effective components participating in the reaction to interact with the alkaline excitation raw material, improving the reaction rate and the generation amount of the reaction product. On this basis, based on the common ion effect and salt effect of the setting accelerator, it can chemically react with the reaction product of the alkali-activated low-calcium silico-aluminate composite cement to form a complex salt, a complex or a difficultly soluble compound with a smaller solubility product, thereby increasing the precipitation rate of the reaction product, accelerating the hydration process of the slurry, and promoting the setting and hardening of the matrix. In summary, through the excitation action of the alkaline excitation raw material and the synergistic promotion effect among the super dispersant, the solubilizer and the setting accelerator, the synergistic development of the setting and hardening performance and the mechanical properties of the alkali-activated low-calcium silico-aluminate composite cement under room temperature conditions is realized.

[0016] The application has the beneficial effects that: the application provides a preparation method of a fast-setting alkali-activated low calcium silico-aluminate composite cement without high-temperature curing, avoids the high-temperature activation link in the preparation process of the existing alkali-activated low calcium silico-aluminate composite cement, and realizes the low-energy-consumption and low-cost preparation of the alkali-activated low calcium silico-aluminate composite cement. Meanwhile, the realization of the synergistic development target of the setting and hardening performance and the mechanical performance of the alkali-activated low calcium silico-aluminate composite cement under room temperature conditions enriches the application scenarios of the alkali-activated low calcium silico-aluminate composite cement and promotes the change from the preparation technology research to the application technology research. In addition, the popularization and application of the application technology are of great significance to improving the utilization rate of low calcium silico-aluminate industrial and mining solid waste and promoting the pollution reduction and carbon reduction synergistic effect measures. DETAILED DESCRIPTION

[0017] In order to make the technical means, innovative features, purposes and effects realized by the application easy to understand, the application is further described below.

[0018] The embodiments described herein are specific concrete embodiments of the application, used to illustrate the concept of the application, and are explanatory and exemplary, and should not be interpreted as limiting the embodiments of the application and the scope of the application. In addition to the embodiments described herein, those skilled in the art can also adopt other technical solutions that are obvious based on the content disclosed in the claims and the description of the application, which include technical solutions that make any obvious substitutions and modifications to the embodiments described herein.

[0019] The application provides a fast-setting alkali-activated low calcium silico-aluminate composite cement without high-temperature curing, which comprises main components and function regulating components. The main components are measured as follows in terms of mass percentage: low calcium silico-aluminate raw material 60%-75%, alkali-activated raw material 25%-40%, and the sum of the two is 100%. The low calcium silico-aluminate raw material is one or two of fly ash, coal gangue, red mud and lithium slag, with the content of CaO less than 8% and the sum of the contents of SiO2 and Al2O3 more than 30%; the alkali-activated raw material is one or two of tetrabutylammonium hydroxide, methyltriethylammonium hydroxide, hexamethonium hydroxide and benzyltrimethylammonium hydroxide. In addition, the function regulating components are additionally added, with the mass of the low calcium silico-aluminate raw material in the main components being 100%, and the dosages of the function regulating components being dispersant 2%-8%, solubilizer 5%-10% and coagulant 1%-10% respectively.

[0020] The hyperdispersant in the function regulating components is one or two of propane sulfonic acid pyridine and octadecylamine acetate, the solubilizer in the function regulating components is one or two of sodium secondary alkyl sulfonate, sodium octyl sulfonate and polyoxyethylene sorbitan fatty acid ester, and the coagulant in the function regulating components is one or two of calcium citrate, calcium threonate and calcium polyphosphate.

[0021] The preparation method of the fast-setting alkali-activated low calcium silico-aluminate composite cement without high-temperature curing comprises the following steps.

[0022] Raw material grinding: the low calcium silico-aluminate raw material in the main component is placed in a ball mill for grinding, so that the surface area of the obtained powder is controlled at 300 m 2 / kg-500 m 2 / kg.

[0023] Mixing: the powder obtained by grinding is placed in a mixer, and the alkaline-activated raw material is added first and mixed and stirred for 30 minutes. Then, according to the specified mass percentage, the functional control components are additionally added, and the addition sequence is: first, the hyperdispersant is added and stirred for 15 minutes, then the solubilizer is added and stirred for 15 minutes, and finally the coagulant is added and continuously stirred for 30 minutes, to obtain the fast-setting alkali-activated low calcium silico-aluminate composite cement without high-temperature curing.

[0024] To further embody the effects brought by the present application, the present application is further described in detail below in combination with specific cases. The low calcium silico-aluminate raw material and the alkaline-activated raw material in the main components of the listed cases are represented by lithium slag and hexamethonium hydroxide respectively, and the sum of the two is 100%. The main chemical components of the lithium slag used in the present application are as follows: CaO content 4%-7%, SiO2 content 52%-56%, Al2O3 content 16%-19%, MgO content 0.8%-1.5%, Fe2O3 content 1%-3%, SO3 content 3%-7%, K2O content 0.1%-0.5%, Na2O content 0.1%-0.5%, and other unavoidable impurities content 0.1%-0.8%. According to the mass of the lithium slag being 100%, the functional control components are represented by pyridinium propane sulfonate, sodium octyl sulfonate and calcium threonate. The specific details of each case and the technical effects are described as follows.

[0025] Example 1

[0026] According to the mass percentage, the raw materials in the main components are weighed, wherein the functional control components are additionally added according to the mass of the low calcium silico-aluminate raw material component in the main components being 100%, and the specific details are as follows:

[0027] Main component: lithium slag 60%, hexamethonium hydroxide 40%, and the sum of the two is 100%. The CaO content of the lithium slag used in this example is 4.3%, the SiO2 content is 52.6%, the Al2O3 content is 16.8%, and the sum of the SiO2 and Al2O3 contents is 69.4%.

[0028] Functional control components (added additionally according to the mass of the low calcium silico-aluminate raw material component in the main components being 100%): pyridinium propane sulfonate 2%, sodium octyl sulfonate 5%, and calcium threonate 1%.

[0029] ① Raw material grinding: accurately take 5 kg of low calcium silicate alumina raw material lithium slag and place it in a ball mill for grinding, to obtain lithium slag powder with a specific surface area of 300 m 2 / kg-350 m 2 / kg.

[0030] ② Mixing: according to the mass percentage, the lithium slag powder obtained in step ① is placed in a mixer, first add the alkaline activator raw material hexamethonium hydroxide and mix for 30 min; then according to the mass of the low calcium silicate alumina raw material lithium slag in the main component being 100%, additional functional control components are added, the order of addition is: first add pyridinium propanesulfonate and stir for 15 min, then add sodium octyl sulfonate and stir for 15 min, finally add calcium threonate and continue to stir for 30 min, to obtain the fast-setting type alkali-activated low calcium silicate alumina composite cement without high temperature curing.

[0031] Example 2

[0032] According to the mass percentage, the main components are weighed, among which the functional control components are additionally added according to the mass of the low calcium silicate alumina component in the main component being 100%, as follows:

[0033] Main component: lithium slag 66%, hexamethonium hydroxide 34%, the sum of which is 100%. The CaO content of the lithium slag used in this example is 4.8%, the SiO2 content is 53.5%, the Al2O3 content is 17.4%, and the sum of the SiO2 and Al2O3 contents is 70.9%.

[0034] Functional control components (added additionally according to the mass of the low calcium silicate alumina component in the main component being 100%): pyridinium propanesulfonate 4%, sodium octyl sulfonate 7%, calcium threonate 4%.

[0035] ① Raw material grinding: accurately take 5 kg of low calcium silicate alumina raw material lithium slag and place it in a ball mill for grinding, to obtain lithium slag powder with a specific surface area of 350 m 2 / kg-400 m 2 / kg.

[0036] ② Mixing: according to the mass percentage, the lithium slag powder obtained in step ① is placed in a mixer, first add the alkaline activator raw material hexamethonium hydroxide and mix for 30 min; then according to the mass of the low calcium silicate alumina raw material lithium slag in the main component being 100%, additional functional control components are added, the order of addition is: first add pyridinium propanesulfonate and stir for 15 min, then add sodium octyl sulfonate and stir for 15 min, finally add calcium threonate and continue to stir for 30 min, to obtain the fast-setting type alkali-activated low calcium silicate alumina composite cement without high temperature curing.

[0037] Example 3

[0038] The raw materials in the main component are weighed by mass percentage, wherein the functional regulation component is additionally added based on the mass of the low calcium silicate and alumina raw material component in the main component being 100%, and the specific contents are as follows:

[0039] Main component: lithium slag 70%, hexamethonium hydroxide 30%, and the sum of the two is 100%. The CaO content of the lithium slag used in this example is 5.5%, the SiO2 content is 54.3%, the Al2O3 content is 18.8%, and the sum of the SiO2 and Al2O3 contents is 73.1%.

[0040] Functional regulation component (added additionally based on the mass of the low calcium silicate and alumina raw material component in the main component being 100%): pyridinium propane sulfonate 7%, sodium octyl sulfonate 9%, calcium threonate 7%.

[0041] ① Raw material grinding: 5 kg of low calcium silicate and alumina raw material lithium slag is accurately weighed and placed in a ball mill for grinding to obtain lithium slag powder with a specific surface area of 400 m 2 / kg-450 m 2 / kg.

[0042] ② Mixing: the lithium slag powder obtained in step ① is placed in a mixer according to mass percentage, and the alkaline activation raw material hexamethonium hydroxide is first added and mixed and stirred for 30 min; then the functional regulation component is added additionally based on the mass of the low calcium silicate and alumina raw material lithium slag in the main component being 100%, and the addition sequence is: pyridinium propane sulfonate is first added and stirred for 15 min, then sodium octyl sulfonate is added and stirred for 15 min, and finally calcium threonate is added and stirred for 30 min, to obtain the fast-setting type alkaline-activated low calcium silicate and alumina composite cement which does not require high-temperature curing.

[0043] Example 4

[0044] The raw materials in the main component are weighed by mass percentage, wherein the functional regulation component is additionally added based on the mass of the low calcium silicate and alumina raw material component in the main component being 100%, and the specific contents are as follows:

[0045] Main component: lithium slag 75%, hexamethonium hydroxide 25%, and the sum of the two is 100%. The CaO content of the lithium slag used in this example is 6.2%, the SiO2 content is 55.2%, the Al2O3 content is 18.2%, and the sum of the SiO2 and Al2O3 contents is 73.4%.

[0046] Functional regulation component (added additionally based on the mass of the low calcium silicate and alumina raw material component in the main component being 100%): pyridinium propane sulfonate 8%, sodium octyl sulfonate 10%, calcium threonate 10%.

[0047] 2 / kg-500m 2 / kg of lithium slag powder.

[0048] ②Mixing: according to the mass percentage, the lithium slag powder obtained in step ① is placed in a mixer, first add the alkaline activated raw material hexamethonium hydroxide and mix and stir for 30 min; then according to the mass of the main component low calcium siliceous and aluminous raw material lithium slag is 100%, additional functional control components are added, the order of addition is: first add propane sulfonic acid pyridine and stir for 15 min, then add sodium octyl sulfonate and stir for 15 min, finally add calcium threonate and continue to stir for 30 min, to obtain the fast-setting type alkali-activated low calcium siliceous and aluminous composite cement without high temperature curing.

[0049] Comparative Example 1

[0050] In this comparative example, no super dispersant propane sulfonic acid pyridine is added, and the rest is the same as example 1.

[0051] Comparative Example 2

[0052] In this comparative example, no solubilizing agent sodium octyl sulfonate is added, and the rest is the same as example 2.

[0053] Comparative Example 3

[0054] In this comparative example, no coagulant calcium threonate is added, and the rest is the same as example 3.

[0055] Comparative Example 4

[0056] In this comparative example, no super dispersant propane sulfonic acid pyridine and solubilizing agent sodium octyl sulfonate are added, and the rest is the same as example 4.

[0057] Comparative Example 5

[0058] In this comparative example, no functional control component is added, and the rest is the same as example 1.

[0059] Comparative Example 6

[0060] In this comparative example, the alkaline activated raw material hexamethonium hydroxide is replaced by a mixture of 40% inorganic alkaline activated raw material [NaOH+Na2SiO3], the modulus of the mixture is 1.4, the alkali content is 8%, and the rest is the same as example 1.

[0061] Comparative Example 7

[0062] ​In the present comparative example, the basic activating raw material hexamethonium hydroxide is replaced by a mixture of 40% inorganic basic activating raw material [NaOH+Na2SiO3], the mixture has a water glass modulus of 1.4 and an alkali content of 8%, and no functional regulating component is added, and the rest is the same as example 1.

[0063] The setting time of each example and comparative example is tested according to GB / T 1346-2019 "Cement Standard Consistency, Setting Time and Stability Test Method"; the fluidity of each example and comparative example is tested according to GB / T 8077-2012 "Concrete Admixture Homogeneity Test Method"; and the compressive strength of each example and comparative example at 3 days, 7 days and 28 days is tested according to GB / T 17671-2021 "Cement Mortar Strength Test Method (ISO Method)". The test results of each example and comparative example are shown in Table 1.

[0064] Table 1 Performance indicators of fast-setting alkali-activated low calcium silico-aluminate composite cement without high-temperature curing

[0065]

[0066] Note: "-" indicates that the sample has no strength

[0067] As can be seen from the results in Table 1, comparative example 7 is an existing alkali-activated low calcium silico-aluminate composite cement prepared by using inorganic basic activating raw material, which has very slow setting and hardening, and the final setting time is as long as 76.5 hours, and the compressive strength of the obtained cement is low. In comparison, in the present application, the organic basic activating raw material is used, and under the synergistic action of the functional regulating component, the setting time of the alkali-activated low calcium silico-aluminate composite cement in examples 1-4 is significantly shortened, and the fluidity of the fresh paste and the compressive strength of the hardened paste are both obviously improved and increased. The synergistic development of the setting and hardening performance and the mechanical properties of the alkali-activated low calcium silico-aluminate composite cement under room temperature conditions is achieved.

[0068] Compared with example 1, in comparative example 1, due to the absence of the super dispersant in the functional regulating component, the dispersibility of the solid particles in the paste is poor during the reaction, which reduces the effective contact area between the particles and the basic activating raw material, resulting in a decrease in the reaction rate of the paste, an extension of the setting and hardening time, and a significant decrease in the fluidity of the fresh paste and the compressive strength of the hardened paste at each age.

[0069] Compared with example 2, in comparative example 2, due to the absence of the solubilizer in the functional regulating component, the concentration of the insoluble particles in the liquid phase of the paste is high, which inhibits the dissolution of the effective components and reduces the dissolution degree of the solid particles, resulting in a slow reaction rate of the paste, an extension of the setting time, and a significant decrease in the compressive strength of the hardened paste at each age, but the absence of this component has little effect on the fluidity of the fresh paste.

[0070] Compared with Example 3, the absence of the coagulant in the functional regulation component of Comparative Example 3 reduces the effective site when the reaction product nucleates, reduces the precipitation rate of the product, and results in the extension of the setting time of the slurry. The absence of the coagulant has a certain improvement on the fluidity of the freshly mixed slurry, but the compressive strength of the hardened slurry at each age is reduced.

[0071] Compared with Example 4, the absence of the hyperdispersant and the solubilizer in the functional regulation component of Comparative Example 4 reduces the dispersion degree and the solubility of the particles in the slurry, reduces the reaction rate and the generation amount of the reaction product of the system. Even under the action of the coagulant, the setting time of the slurry is significantly extended, and the fluidity of the freshly mixed slurry and the compressive strength of the hardened slurry at each age are significantly reduced.

[0072] Compared with Example 1, the absence of the functional regulation component in Comparative Example 5 reduces the dispersion degree, the solubility of the particles in the slurry, and the precipitation rate of the reaction product, which further results in the significant extension of the setting time of the slurry, and the significant reduction of the fluidity of the freshly mixed slurry and the compressive strength of the hardened slurry at each age.

[0073] Compared with Example 1, the replacement of the organic alkaline activator with the mixture of the inorganic alkaline activator [NaOH+Na2SiO3] in Comparative Example 6 reduces the dispersion degree of the hyperdispersant in the functional regulation component to the particles in the slurry, reduces the contact area of the particles and the alkaline activator, reduces the solubility of the particles and the generation amount of the reaction product in the slurry, which further results in the extension of the setting time of the slurry, and the reduction of the fluidity of the freshly mixed slurry and the compressive strength of the hardened slurry at each age. The results also show that the functional regulation component is also applicable to the regulation of the setting and hardening properties when the inorganic alkaline activator is used to prepare the alkali-activated low-calcium silico-aluminate composite cement.

[0074] The above examples are only used to explain the present application and do not constitute a limitation on the scope of the claims. Other alternative means that can be thought of by those skilled in the art based on the content of the present application should be within the protection scope of the claims of the present application.

Claims

1. A fast-setting, alkali-activated, low-calcium silicate-alumina composite cement that does not require high-temperature curing, characterized in that... It includes main components and functional control components; the main components are measured by mass percentage as follows: (1) low-calcium silicate alumina raw material 60%-75%, (2) alkaline activating raw material 25%-40%, the sum of the two is 100%; in addition, based on the mass of low-calcium silicate alumina raw material in the main components being 100%, additional functional control components are added, and the dosage of each functional control component is as follows: (1) superdispersant 2%-8%, (2) solubilizer 5%-10%, (3) coagulant 1%-10%; The low-calcium silicate alumina raw material is one or two of fly ash, coal gangue, red mud, and lithium slag. The chemical composition of the low-calcium silicate alumina raw material contains less than 8% CaO by mass and more than 30% SiO2 and Al2O3 by mass. The alkaline activating raw material is one or two of tetrabutylammonium hydroxide, methyltriethylammonium hydroxide, hexamethyldiammonium hydroxide, and benzyltrimethylammonium hydroxide. The superdispersant in the functional regulating component is one or two of pyridinium propane sulfonate and octadecylamine acetate; the solubilizer in the functional regulating component is one or two of sodium secondary alkyl sulfonate, sodium octyl sulfonate, and polyoxyethylene sorbitan fatty acid ester; the coagulant in the functional regulating component is one or two of calcium citrate, calcium threonate, and calcium polyphosphate.

2. A method for preparing a fast-setting, alkali-activated, low-calcium silicate-alumina composite cement that does not require high-temperature curing as described in claim 1, characterized in that... The steps are as follows: 1) Raw material grinding: According to the mass percentage, the low-calcium silicate alumina raw material of the main components is placed in a ball mill for grinding, so that the surface area of ​​the obtained powder is controlled at 300m². 2 / kg-500m 2 / kg; 2) Mixing: Place the powder obtained in step 1) into a mixer, add the alkaline activating raw material according to the mass percentage and mix for 30 minutes; then add the functional regulating component in the following order: first add the super dispersant and mix for 15 minutes, then add the solubilizer and mix for 15 minutes, and finally add the accelerator and continue mixing for 30 minutes to obtain the fast-setting alkali-activated low-calcium silicate alumina composite cement that does not require high-temperature curing.

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