Low-carbon super sulfate cement and preparation method thereof

Abstract

The invention relates to the technical field of cementing materials, and discloses low-carbon super-sulfate cement and a preparation method thereof.The low-carbon super-sulfate cement is prepared from, by weight, 80%-85% of blast furnace slag, 1%-5% of carbide slag and 10%-15% of desulfurized gypsum, the carbide slag serves as an alkali activator to destroy the slag structure and promote decomposition of a slag glass network body, and the desulfurized gypsum serves as an alkali activator to destroy the slag glass network body; the low-carbon super-sulfate cement prepared by the method has good early strength and later strength, and the carbon emission of the super-sulfate cement is reduced as the ettringite, the C-(A)-S-H gel and other hydration products are generated. And secondly, resource utilization of the industrial solid waste is combined with preparation of the cementing material, so that the risks of stockpiling and pollution of the industrial solid waste are effectively reduced, and comprehensive utilization of the industrial solid waste is promoted.

Description

Technical Field

[0001] The invention belongs to the technical field of cementitious materials, and in particular relates to a low-carbon supersulfate cement and a preparation method thereof. Background Art

[0002] Supersulphated cement is a hydraulic cementitious material, mainly composed of 75%~85% granulated blast furnace slag, 10%~20% sulfates (industrial byproduct gypsum, etc.) and 1%~5% alkaline activator (such as cement clinker, calcium hydroxide or lime, etc.). The optimal amount of activator depends on its specific type. At present, the commonly used alkaline activators for supersulphated cement are silicate cement, lime and strong alkali. However, under the condition of using cement or lime as activator and the optimal amount, it is difficult to effectively activate the pozzolanic activity of slag due to the low pH value of the system, resulting in low early strength of supersulphated cement. Although the use of strong alkali can significantly increase the pH value, thereby enhancing the early reaction activity of slag, the pH range of strong alkali is usually between 12 and 14, which has high corrosiveness and safety risks. In addition, the production process of strong alkali has high energy consumption, which violates the original design intention of supersulphated cement to be low-carbon and environmentally friendly.

[0003] CN118930097A discloses a red mud desulfurization slag-based supersulfate cement and a preparation method thereof. The raw materials used in the supersulfate cement include: red mud desulfurization slag, modified red mud desulfurization slag, red mud, and clinker. Although the solution of this patent improves the early strength of supersulfate cement, the use of clinker in the raw materials increases carbon emissions.

[0004] CN114735955A discloses a desulfurized gypsum-based supersulfate cement and a preparation method thereof, wherein the desulfurized gypsum-based supersulfate cement comprises the following components in mass ratio: 10% to 40% desulfurized gypsum, 1% to 10% general cement, 30% to 60% slag powder, 5% to 30% steel slag, 5% to 30% fly ash, and 1% to 10% composite activator. The patent introduces desulfurized gypsum into supersulfate cement, which solves the problem of low early strength and slow strength improvement of supersulfate cement. However, the patent uses strong alkali as an activator, which not only greatly increases costs and carbon emissions, but also brings greater safety risks. Summary of the invention

[0005] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a low-carbon super-sulfate cement and a preparation method thereof, which can utilize industrial alkaline solid waste carbide slag and sulfate solid waste desulfurization gypsum, reduce the production cost of super-sulfate cement and the pollution of industrial waste to the environment, and at the same time improve the mechanical properties of super-sulfate cement.

[0006] To achieve the above object, the present invention is implemented by the following technical solutions: In a first aspect, the present invention provides a low-carbon supersulfate cement, comprising raw materials in the following weight percentages: blast furnace slag 80% - 85%, carbide slag 1% - 5%, and desulfurized gypsum 10% - 15%.

[0007] A further improvement of the present invention lies in that the basicity coefficient of the blast furnace slag is less than 1 and the activity coefficient is greater than 0.25.

[0008] A further improvement of the present invention lies in that, by mass percentage, the blast furnace slag mainly contains 30 - 40 wt% CaO, 14 - 17 wt% Al2O3, and 30 - 40 wt% SiO2, and the balance is other components.

[0009] A further improvement of the present invention lies in that the particle size of the blast furnace slag is not less than 600 mesh.

[0010] A further improvement of the present invention lies in that, by mass percentage, the carbide slag mainly contains 85 - 95 wt% CaO and 1 - 10 wt% SiO2, and the balance is other components.

[0011] A further improvement of the present invention lies in that the particle size of the carbide slag is not less than 100 mesh.

[0012] A further improvement of the present invention lies in that the desulfurized gypsum mainly contains 40 - 50 wt% CaO and 45 - 55 wt% SO3, and the balance is other components.

[0013] A further improvement of the present invention lies in that the particle size of the desulfurized gypsum is not less than 100 mesh.

[0014] In a second aspect, the present invention also provides a preparation method of a low-carbon supersulfate cement, comprising: Mixing blast furnace slag, carbide slag, and desulfurized gypsum according to the formula amounts, and obtaining low-carbon supersulfate cement after mixing evenly.

[0015] A further improvement of the present invention lies in that the blast furnace slag, carbide slag, and desulfurized gypsum are each ground first before mixing to meet the particle size requirements.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a low-carbon supersulphate cement, which uses blast furnace slag, carbide slag and desulphurization gypsum as raw materials. Among them, the carbide slag acts as an alkali activator to destroy the slag structure, promote the disintegration of the slag glass network, and generate hydration products such as ettringite and C-(A)-S-H gel, so that the prepared low-carbon supersulphate cement has good early strength and late strength, and also reduces the carbon emissions of the supersulphate cement. Secondly, the present invention combines the resource utilization of industrial solid waste with the preparation of cementitious materials, effectively reducing the risk of industrial solid waste stacking and pollution, and promoting the comprehensive utilization of industrial solid waste.

[0017] The present invention also provides a preparation method of the low-carbon supersulphate cement. By mixing the formulated amounts of blast furnace slag, carbide slag and desulphurization gypsum, the low-carbon supersulphate cement can be obtained. The preparation method is simple and efficient. Detailed implementation manners

[0018] To enable those skilled in the art to understand the features and effects of the present invention, the following is a general description and definition of the terms and expressions mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meanings understood by those skilled in the art for the present invention. In case of conflict, the definitions in this specification shall prevail.

[0019] The theories or mechanisms described and disclosed herein, whether correct or incorrect, shall not limit the scope of the present invention in any way, that is, the content of the present invention can be implemented without being limited by any specific theory or mechanism.

[0020] In this article, all features defined in the form of numerical ranges or percentage ranges, such as numerical values, quantities, contents and concentrations, are only for the sake of brevity and convenience. Accordingly, the description of a numerical range or percentage range should be regarded as having covered and specifically disclosed all possible sub-ranges and individual numerical values within the range (including integers and fractions).

[0021] In this article, unless otherwise specified, the terms "comprise", "include", "contain", "have" or similar expressions cover the meanings of "consist of" and "consist essentially of". For example, "A comprises a" covers the meanings of "A comprises a and others" and "A only comprises a".

[0022] In this article, for the sake of brevity of description, all possible combinations of all technical features in each embodiment or example are not described. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each embodiment or example can be combined arbitrarily, and all possible combinations should be considered as the scope described in this specification.

[0023] The present invention provides a low-carbon supersulphate cement, which comprises raw materials in the following weight percentages: 80% - 85% of blast furnace slag, 1% - 5% of carbide slag, and 10% - 15% of desulphurization gypsum.

[0024] Among them, the basicity coefficient of the blast furnace slag adopted in the present invention is less than 1, the activity coefficient is greater than 0.25, and the particle size of the blast furnace slag is not less than 600 mesh; by mass percentage, the blast furnace slag mainly contains 30 - 40wt% CaO, 14 - 17wt% Al2O3, and 30 - 40wt% SiO2, and the balance is other components. As shown in Table 1, the other components are oxides such as SO3, Fe2O3, Na2O, MgO, TiO2, etc. that will not affect the activity of the blast furnace slag.

[0025] Carbide slag is a by-product of acetylene production, and the pH of the slag liquid exceeds 13. Its function in the present invention is to act as an alkali activator to destroy the slag structure, promote the disintegration of the slag glass network body, and generate hydration products such as ettringite and C-(A)-S-H gel.

[0026] The particle size of the carbide slag is not less than 100 mesh; by mass percentage, the carbide slag mainly contains 85 - 95wt% CaO and 0 - 10wt% SiO2, and the balance is other components. As shown in Table 1, the other components are oxides such as Al2O3, SO3, Fe2O3, Na2O, MgO, TiO2, etc. that will not affect the activity of the carbide slag.

[0027] Desulphurization gypsum is used as a sulphate activator, and its main phase is CaSO4·0.5H2O. The desulphurization gypsum used in the present invention has been dehydrated, and the main oxides are SO3 and CaO, which exist in the desulphurization gypsum in the form of CaSO4·0.5H2O crystal phase.

[0028] The particle size of the desulphurization gypsum is not less than 100 mesh; by mass percentage, the desulphurization gypsum mainly contains 40 - 50wt% CaO and 45 - 55wt% SO3, and the balance is other components. As shown in Table 1, the other components are oxides such as SiO2, Al2O3, Fe2O3, Na2O, MgO, TiO2, etc. that will not affect the activity of the desulphurization gypsum.

[0029] Table 1 Main components of raw materials

[0030] The present invention also provides a preparation method of the low-carbon supersulphate cement, which includes: Mixing the blast furnace slag, carbide slag, and desulphurization gypsum according to the formula amount, and obtaining the low-carbon supersulphate cement after mixing evenly.

[0031] Among them, blast furnace slag, carbide slag, and desulfurized gypsum are each ground before mixing to meet the particle size requirements. Specifically, the particle size of blast furnace slag is not less than 600 mesh; the particle size of carbide slag is not less than 100 mesh; the particle size of desulfurized gypsum is not less than 100 mesh.

[0032] The following will further elaborate on the present invention in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of this application.

[0033] Conventional instrument and equipment in the art are used in the following embodiments. For the experimental methods without specific conditions noted in the following embodiments, they are usually carried out under conventional conditions or according to the conditions recommended by the manufacturer. Various raw materials are used in the following embodiments. Unless otherwise stated, commercially available products are used, and their specifications are the conventional specifications in the art. In the specification of the present invention and the following embodiments, unless otherwise specified, "%" represents weight percentage, "parts" represents weight parts, and the ratio represents weight ratio.

[0034] Example 1: As shown in Table 2, in this example, low-carbon supersulfate cement is prepared using 84% blast furnace slag, 1% carbide slag, and 15% desulfurized gypsum. First, the above-mentioned blast furnace slag, carbide slag, and desulfurized gypsum are respectively ground to meet the particle size requirements, and then mixed in a mixer according to the formula amount. After mixing evenly, low-carbon supersulfate cement is obtained.

[0035] The low-carbon supersulfate cement obtained in this example is used to prepare 40mm×40mm×40mm triple mold specimens according to the national standard "Test Method for Strength of Cement Mortar (GB / T 17671-2021)". After standard curing (curing temperature is 20±1°C, relative humidity 95%) for 24h, the mold is removed, and it is continuously cured under the same conditions until 3d, 7d, and 28d to test the compressive strength. The test results are shown in Table 3.

[0036] As can be seen from Table 3, the compressive strength of the low-carbon supersulfate cement prepared in this example is 7.8 MPa at 3 days, 40.2 MPa at 7 days, and 49.4 MPa at 28 days.

[0037] According to the GB / T 1346-2011 standard, the standard consistency water requirement and setting time of the sample of the low-carbon supersulfate cement obtained in this example are tested using a Vicat apparatus. The setting time is detected every minute, and the test result is the average value of three test results. The test results are shown in Table 4.

[0038] As can be seen from Table 4, the initial setting time of the low-carbon supersulfate cement prepared in this example is 8 min, the final setting time is 13 min, and the water requirement for normal consistency is 46%.

[0039] Example 2: As shown in Table 2, in this example, 83% blast furnace slag, 2% carbide slag, and 15% desulfurized gypsum are used to prepare low-carbon supersulfate cement. First, the above blast furnace slag, carbide slag, and desulfurized gypsum are respectively ground to meet the particle size requirements, and then mixed in a mixer according to the formula amount. After mixing evenly, low-carbon supersulfate cement is obtained.

[0040] The low-carbon supersulfate cement obtained in this example is used to prepare 40 mm×40 mm×40 mm triple mold specimens according to the national standard "Test Method for Strength of Cement Mortar (GB / T 17671-2021)". After standard curing (curing temperature is 20±1°C, relative humidity is 95%) for 24 h, the mold is removed, and the specimens are continuously cured under the same conditions until 3 d, 7 d, and 28 d to test the compressive strength. The test results are shown in Table 3.

[0041] As can be seen from Table 3, the compressive strength of the low-carbon supersulfate cement prepared in this example is 16.2 MPa at 3 days, 35.9 MPa at 7 days, and 37.2 MPa at 28 days.

[0042] The low-carbon supersulfate cement obtained in this example is used to test the water requirement for normal consistency and setting time of the sample according to the GB / T 1346-2011 standard using a Vicat apparatus. The setting time is detected every minute, and the test result is the average value of three test results. The test results are shown in Table 4.

[0043] As can be seen from Table 4, the initial setting time of the low-carbon supersulfate cement prepared in this example is 8 min, the final setting time is 11 min, and the water requirement for normal consistency is 46%.

[0044] Example 3: As shown in Table 2, in this example, 82% blast furnace slag, 3% carbide slag, and 15% desulfurized gypsum are used to prepare low-carbon supersulfate cement. First, the above blast furnace slag, carbide slag, and desulfurized gypsum are respectively ground to meet the particle size requirements, and then mixed in a mixer according to the formula amount. After mixing evenly, low-carbon supersulfate cement is obtained.

[0045] The low-carbon supersulfate cement obtained in this example is used to prepare 40 mm×40 mm×40 mm triple mold specimens according to the national standard "Test Method for Strength of Cement Mortar (GB / T 17671-2021)". After standard curing (curing temperature is 20±1°C, relative humidity is 95%) for 24 h, the mold is removed, and the specimens are continuously cured under the same conditions until 3 d, 7 d, and 28 d to test the compressive strength. The test results are shown in Table 3.

[0046] As can be seen from Table 3, the compressive strength of the low-carbon supersulphate cement prepared in this example was 20.1 MPa at 3 days, 35.0 MPa at 7 days, and 43.7 MPa at 28 days.

[0047] According to the GB / T 1346-2011 standard, the water requirement for normal consistency and setting time of the samples of the low-carbon supersulphate cement obtained in this example were tested using a Vicat apparatus. The setting time was detected every minute, and the test results were the average of three test results. The test results are shown in Table 4.

[0048] As can be seen from Table 4, the initial setting time of the low-carbon supersulphate cement prepared in this example was 6 min, the final setting time was 11 min, and the water requirement for normal consistency was 47%.

[0049] Example 4: As shown in Table 2, in this example, 81% blast furnace slag, 4% carbide slag, and 15% desulphurization gypsum were used to prepare low-carbon supersulphate cement. First, the above blast furnace slag, carbide slag, and desulphurization gypsum were respectively ground to meet the particle size requirements, and then mixed in a mixer according to the formula amount. After mixing evenly, low-carbon supersulphate cement was obtained.

[0050] The low-carbon supersulphate cement obtained in this example was used to prepare 40 mm×40 mm×40 mm triple mold specimens according to the national standard "Test Method for Strength of Cement Mortar (GB / T 17671-2021)". After standard curing (curing temperature 20±1 °C, relative humidity 95%) for 24 h, the molds were removed, and the specimens were continuously cured under the same conditions until the compressive strength was tested at 3 d, 7 d, and 28 d. The test results are shown in Table 3.

[0051] As can be seen from Table 3, the compressive strength of the low-carbon supersulphate cement prepared in this example was 18.4 MPa at 3 days, 24.3 MPa at 7 days, and 29.7 MPa at 28 days.

[0052] According to the GB / T 1346-2011 standard, the water requirement for normal consistency and setting time of the samples of the low-carbon supersulphate cement obtained in this example were tested using a Vicat apparatus. The setting time was detected every minute, and the test results were the average of three test results. The test results are shown in Table 4.

[0053] As can be seen from Table 4, the initial setting time of the low-carbon supersulphate cement prepared in this example was 5 min, the final setting time was 10 min, and the water requirement for normal consistency was 47%.

[0054] Example 5: As shown in Table 2, in this example, low-carbon supersulphate cement is prepared using 80% blast furnace slag, 5% carbide slag, and 15% desulphurization gypsum. First, the above-mentioned blast furnace slag, carbide slag, and desulphurization gypsum are respectively ground to meet the particle size requirements, and then mixed in a mixer according to the formula amount. After mixing evenly, low-carbon supersulphate cement is obtained.

[0055] The low-carbon supersulphate cement obtained in this example is used to prepare 40mm×40mm×40mm triple mold specimens according to the national standard "Test Method for Strength of Cement Mortar (GB / T 17671-2021)". After standard curing (curing temperature is 20±1°C, relative humidity is 95%) for 24h, the mold is removed, and the specimens are continuously cured under the same conditions until 3d, 7d, and 28d to test the compressive strength. The test results are shown in Table 3.

[0056] As can be seen from Table 3, the compressive strength of the low-carbon supersulphate cement prepared in this example is 18.8MPa at 3 days, 23.9MPa at 7 days, and 27.0MPa at 28 days.

[0057] According to the GB / T 1346-2011 standard, the standard consistency water requirement and setting time of the low-carbon supersulphate cement obtained in this example are tested using a Vicat apparatus. The setting time is detected every minute, and the test results are the average of three test results. The test results are shown in Table 4.

[0058] As can be seen from Table 4, the initial setting time of the low-carbon supersulphate cement prepared in this example is 6min, the final setting time is 9min, and the standard consistency water requirement is 47%.

[0059] Example 6: As shown in Table 2, in this example, low-carbon supersulphate cement is prepared using 85% blast furnace slag, 5% carbide slag, and 10% desulphurization gypsum. First, the above-mentioned blast furnace slag, carbide slag, and desulphurization gypsum are respectively ground to meet the particle size requirements, and then mixed in a mixer according to the formula amount. After mixing evenly, low-carbon supersulphate cement is obtained.

[0060] The low-carbon supersulphate cement obtained in this example is used to prepare 40mm×40mm×40mm triple mold specimens according to the national standard "Test Method for Strength of Cement Mortar (GB / T 17671-2021)". After standard curing (curing temperature is 20±1°C, relative humidity is 95%) for 24h, the mold is removed, and the specimens are continuously cured under the same conditions until 3d, 7d, and 28d to test the compressive strength. The test results are shown in Table 3.

[0061] As can be seen from Table 3, the compressive strength of the low-carbon supersulphate cement prepared in this example is 19.2MPa at 3 days, 24.5MPa at 7 days, and 27.8MPa at 28 days.

[0062] According to the GB / T 1346-2011 standard, the water requirement for normal consistency and setting time of the low-carbon supersulfate cement obtained in this example were tested using a Vicat apparatus. The setting time was detected every minute, and the test results were the average of three test results. The test results are shown in Table 4.

[0063] As can be seen from Table 4, the initial setting time of the low-carbon supersulfate cement prepared in this example was 6 min, the final setting time was 9 min, and the water requirement for normal consistency was 47%.

[0064] Comparative Example 1: As shown in Table 2, in this comparative example, low-carbon supersulfate cement was prepared using 85% blast furnace slag and 15% desulfurized gypsum. First, the above-mentioned blast furnace slag, carbide slag, and desulfurized gypsum were respectively ground to meet the particle size requirements, and then mixed in a mixer according to the formula amount. After mixing evenly, low-carbon supersulfate cement was obtained.

[0065] The low-carbon supersulfate cement obtained in Comparative Example 1 was used to prepare 40 mm×40 mm×40 mm triple mold specimens according to the national standard "Test Method for Strength of Cement Mortar (GB / T 17671-2021)". After standard curing (curing temperature 20±1°C, relative humidity 95%) for 24 h, the specimens were demolded and continuously cured under the same conditions until the compressive strength was tested at 3 d, 7 d, and 28 d. The test results are shown in Table 3.

[0066] As can be seen from Table 3, the compressive strength of the low-carbon supersulfate cement prepared in this comparative example was 0.3 MPa at 3 days, 1.6 MPa at 7 days, and 19.7 MPa at 28 days.

[0067] According to the GB / T 1346-2011 standard, the water requirement for normal consistency and setting time of the low-carbon supersulfate cement obtained in this example were tested using a Vicat apparatus. The setting time was detected every minute, and the test results were the average of three test results. The test results are shown in Table 4.

[0068] As can be seen from Table 4, the initial setting time of the low-carbon supersulfate cement prepared in this example was 9 min, the final setting time was 12 min, and the water requirement for normal consistency was 45%.

[0069] Table 2 Mass percentages of each raw material component in different examples

[0070] Table 3 Compressive strengths of the low-carbon supersulfate cement obtained in the examples and comparative examples of the present invention

[0071] As can be seen from Table 3, the compressive strength of Comparative Example 1 was significantly lower at 3 days and 7 days. The main reason was that no alkaline activator was added, resulting in a slow reaction rate of slag. At 28 days, ettringite was formed in the system, and the compressive strength increased to 19.7 MPa. In contrast, Example 1 showed the highest compressive strength at 28 days. However, considering the strength performance at 3 days, 7 days, and 28 days comprehensively, the overall performance of Example 3 was the best. Its 3-day compressive strength had exceeded 20 MPa, and the 28-day strength was only 11.5% lower than that of Example 1. Analyzing the reasons, in the examples, the early compressive strength was mainly contributed by ettringite, and the later strength mainly came from the continuous formation of C-(A)-S-H gel. In the comparative examples, the compressive strength was almost entirely provided by ettringite, lacking the contribution of the later gel phase, thus resulting in a significant strength difference.

[0072] Table 4 Setting time and water requirement for normal consistency in the examples and comparative examples of the present invention

[0073] As can be seen from Table 4, the setting time of each example was less than 1 h. The sample of Comparative Example 1 required 45% water consumption because the blast furnace slag had a finer particle size, and its surface area could absorb more water. In Examples 1 to 6, as the dosage of carbide slag increased, the water requirement for normal consistency increased. In addition, the decrease in the final setting time exceeded the decrease in the initial setting time, gradually narrowing the gap between the two setting times. This was because the alkaline environment provided by carbide slag promoted the dissolution of blast furnace slag, reacted with the sulfate ions provided by desulfurized gypsum to form ettringite, and shortened the setting time.

[0074] The above content is only to illustrate the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. Any modification made on the basis of the technical solution according to the technical idea proposed by the present invention falls within the protection scope of the claims of the present invention.

Claims

1. A low-carbon supersulfate cement, characterized in that, It includes raw materials with the following weight percentages: 80% - 85% blast furnace slag, 1% - 5% carbide slag, and 10% - 15% desulfurized gypsum.

2. A low-carbon supersulphate cement according to claim 1, characterized in that, The basicity coefficient of the blast furnace slag is less than 1, and the activity coefficient is greater than 0.

25.

3. A low-carbon supersulfate cement according to claim 1, characterized in that, By mass percentage, the blast furnace slag mainly contains 30 - 40 wt% CaO, 14 - 17 wt% Al2O3, and 30 - 40 wt% SiO2, with the balance being other components.

4. A low-carbon supersulphate cement according to claim 1, characterized in that, The particle size of the blast furnace slag is not less than 600 mesh.

5. A low-carbon supersulphate cement according to claim 1, characterized in that, By mass percentage, the carbide slag mainly contains 85 - 95 wt% CaO and 1 - 10 wt% SiO2, with the balance being other components.

6. A low-carbon supersulfate cement according to claim 1, characterized in that, The particle size of the carbide slag is not less than 100 mesh.

7. A low-carbon supersulfate cement according to claim 1, characterized in that, By mass percentage, the desulfurized gypsum mainly contains 40 - 50 wt% CaO and 45 - 55 wt% SO3, with the balance being other components.

8. A low-carbon supersulfate cement according to claim 1, characterized in that, The particle size of the desulfurized gypsum is not less than 100 mesh.

9. A method for preparing the low-carbon supersulphate cement according to any one of claims 1-8, characterized in that, It includes: Mix the blast furnace slag, carbide slag, and desulfurized gypsum according to the formula amount, and obtain low-carbon supersulfate cement after mixing evenly.

10. The preparation method of a low-carbon supersulfate cement according to claim 9, characterized in that, Before mixing, the blast furnace slag, carbide slag, and desulfurized gypsum are each ground to meet the particle size requirements.

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