Solid waste-based cementing material prepared from carbonized solid waste material and preparation method of solid waste-based cementing material

Abstract

The invention discloses a solid waste-based cementing material prepared from a carbonized solid waste material and a preparation method of the solid waste-based cementing material, and the solid waste-based cementing material prepared from the carbonized solid waste material comprises a solid waste material subjected to carbon dioxide carbonization treatment and sulphoaluminate cement. The solid waste material is carbonized with carbon dioxide and then compounded with sulphoaluminate cement to obtain the solid waste-based cementing material, so that carbon dioxide can be effectively sealed and stored, the solid waste material can be consumed, the composition of a sulphoaluminate cement hydrated product can be optimized after compounding, the activity of the solid waste material is fully exerted, and the solid waste-based cementing material is prepared. The reaction efficiency of the mixed material is greatly improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cementitious materials, and particularly relates to a solid waste-based cementitious material prepared by carbonizing solid waste materials and a preparation method thereof. BACKGROUND

[0002] Industrial waste slag is produced in large quantities and has low utilization rate, resulting in a large amount of waste slag accumulation. The accumulated waste slag causes various problems such as environmental destruction, land occupation, and economic loss, and therefore needs to be efficiently utilized. Many industrial waste slags rich in calcium, magnesium silicates have potential carbonation activity and have become the main raw materials for carbonation cementitious materials, which is a model for emission reduction and waste utilization.

[0003] Among them, steel slag is a waste material produced during steelmaking, and 1-1.5 tons of steel slag is produced for every 10 tons of crude steel. In China, nearly 100 million tons of steel slag is produced every year, accounting for about 50% of the global output. More than 70% of the steel slag is not utilized, resulting in environmental pollution and resource waste. Harmless disposal and utilization of steel slag has become a major problem in the field of environment and resources in China. Steel slag usually has the characteristics of high alkalinity, difficult grinding, and low activity, and its main components are various calcium silicates and RO phases. However, due to differences in process, additives, raw materials, instruments, etc. during steelmaking, the properties and components of steel slag often show differences. In the construction industry, the research direction of steel slag is to replace clinker or aggregate and to prepare concrete as an admixture. However, due to the large amount of RO phase and the small amount of C3S, the hydration activity is low, and the presence of f-CaO and f-MgO also affects the volume stability of concrete. In the hydration process, steel slag may pollute the environment due to the release of alkali and metal ions. Phosphorus slag is a waste slag with calcium silicate as the main component obtained during the production of yellow phosphorus by using phosphorus ore by thermal method, and is granulated by quenching, that is, granulated electric furnace phosphorus slag, simply referred to as phosphorus slag. China is one of the world's largest producers of yellow phosphorus. Generally, 8-10 tons of phosphorus slag is discharged for every ton of yellow phosphorus produced, and the total utilization rate of phosphorus slag is only 50%.

[0004] Carbon dioxide capture, utilization and storage (CCUS) technology is considered to be one of the most effective methods for controlling human carbon emissions and mitigating climate change in the building materials industry. The CO2 storage technology is mainly to permanently isolate CO2 from the atmosphere. Mineral carbonation CO2 storage technology is considered to be a feasible CO2 capture scheme in addition to amine method and geological storage, because of its advantages such as abundant mineral resources, stable and non-polluting carbonate products, and simple operation. Natural mineral storage of CO2 will consume large-scale mineral resources, while industrial solid waste (fly ash, steel slag, calcium carbide slag, etc.) usually contains a large amount of calcium and magnesium elements, which can be used as a source of calcium ions and magnesium ions required for carbonation to replace natural minerals to capture and store CO2.

[0005] How to combine CCUS technology with solid waste treatment to protect the environment while more efficiently utilizing solid waste materials is a hot issue in the current field. SUMMARY

[0006] To solve the above problems, one of the purposes of the present application is to provide a solid waste-based cementitious material prepared by carbonizing solid waste material, which solves the problem of low solid waste material processing rate and realizes large-scale sequestration of carbon dioxide.

[0007] To achieve the above purposes, the technical solution adopted by the present application is: a solid waste-based cementitious material prepared by carbonizing solid waste material, comprising solid waste material treated by carbonation of carbon dioxide and sulphoaluminate cement.

[0008] The solid waste-based cementitious material is obtained by compounding the solid waste material treated by carbonation of carbon dioxide and sulphoaluminate cement, which not only effectively sequesters carbon dioxide and utilizes solid waste material, but also optimizes the composition of sulphoaluminate cement hydration products, greatly improving the reaction efficiency of the mixed material.

[0009] Further, the ratio of the above-mentioned solid waste material treated by carbonation of carbon dioxide and sulphoaluminate cement satisfies the following formula: (1) 1 / 3×(n SS,SO3 + n CSA,SO3 ) + 1 / 2η×n SS,CaO ≤n SS,Al2O3 + n CSA,Al2O3 ≤η×n SS,CaO +n SS,SO3 + n CSA,SO3 (2) n SS,SiO2 + n CSA,SiO2 + 2η×n SS,CaO + 2×(n SS,SO3 + n CSA,SO3 )≤n SS,CaO + n CSA,CaO ≤ 2×(n SS,SiO2 + n CSA,SiO2 ) + 4η×n SS,CaO + 4×(n SS,SO3 + n CSA,SO3 ) Wherein, n SS,SO3 , n SS,CaO , n SS,Al2O3 , n SS,SiO2 are the molar mass of sulphate, calcium oxide, aluminum oxide and silicon oxide in the solid waste material treated by carbonation of carbon dioxide; n CSA,SO3 , n CSA,CaO , n CSA,Al2O3 , n CSA,SiO2Molar mass of sulfate, calcium oxide, aluminum oxide, and silicon oxide in the sulphoaluminate cement, respectively; η is the carbonation reaction degree of the solid waste, i.e., the ratio of calcium elements that have undergone carbonation reaction to calcium elements that have undergone carbonation reaction at reaction equilibrium.

[0010] According to the above formula, the ratio between the solid waste material and the sulphoaluminate cement after carbonation treatment by carbon dioxide is designed, so that the calcium carbonate, siliceous components, and aluminum components formed after carbonation of the uncarbonated calcium silicate in the solid waste material and the sulphoaluminate cement undergo specific chemical reactions to generate target products such as C-S-H gel, monosulfate type hydrated calcium aluminum (iron) aluminate, monosulfate type hydrated calcium aluminum (iron) aluminate, and trisulfate type hydrated calcium aluminum (iron) aluminate, reduce the components such as free calcium oxide in the solid waste material that are not conducive to the performance of products (such as concrete, building material products, etc.), and fully utilize the carbonated solid waste material. The generated products improve the strength of the material, making up for the strength loss caused by directly adding solid waste to cement-based materials.

[0011] Further, the content of calcium oxide in the above-mentioned solid waste material is not less than 10%.

[0012] Further, the above-mentioned solid waste material is one or more of steel slag, carbide slag, fly ash, municipal solid waste incineration ash, magnesium slag, phosphorus slag, and red mud.

[0013] Further, the above-mentioned solid waste material is steel slag.

[0014] Further, the above-mentioned steel slag is one or more of converter steel slag, electric furnace steel slag, open hearth steel slag, and refined steel slag. The above-mentioned carbide slag is one or both of dry carbide slag and wet carbide slag. The above-mentioned fly ash is one or both of high-calcium fly ash and low-calcium fly ash. The above-mentioned magnesium slag is metallurgical slag generated in the production process of metal magnesium and magnesium products. The above-mentioned phosphorus slag is molten waste slag with calcium silicate as the main component obtained in the process of producing yellow phosphorus by using phosphorus ore by hot method. The above-mentioned red mud is one or more of Bayer process red mud, sintering process red mud, and combined process red mud.

[0015] Further, the above-mentioned carbonation treatment method is selected from one of dry direct carbonation, wet direct carbonation, and carbonation during grinding.

[0016] Further, the dry direct carbonization is a reaction between the carbon dioxide and the solid waste material under a set environmental humidity, a set pressure, and a set temperature; the wet direct carbonization is a reaction between the carbon dioxide and the solid waste material after the carbon dioxide is dissolved in water under a set environmental humidity, a set pressure, and a set temperature; and the carbonization in the grinding process is a carbonization reaction between the solid waste material and the carbon dioxide during the grinding of the solid waste material.

[0017] Further, the environmental humidity of the dry direct carbonization is below 5%, and the environmental humidity of the wet direct carbonization is above 5%.

[0018] For example, the environmental humidity of the dry direct carbonization is 1%, 2%, 3%, 4%, 5%, or a range formed by any two of them; and the environmental humidity of the wet direct carbonization is 5%, 10%, 15%, 20%, 30%, 40%, 50%, 80%, or a range formed by any two of them.

[0019] Further, the carbon dioxide-carbonized solid waste material and the sulphoaluminate cement are in powder form and meet the requirement that the sieve residue of the 45 μm square hole sieve is not more than 50%.

[0020] Further, the sulphoaluminate cement is one or more of fast-hardening sulphoaluminate cement, low-alkalinity sulphoaluminate cement, self-stress sulphoaluminate cement, and sulphoaluminate cement clinker.

[0021] The second object of the present application is to provide a preparation method of a solid waste-based cementitious material prepared by carbonizing solid waste material, comprising the following steps: (1) carbonizing the solid waste material by using a carbon dioxide-containing gas to obtain a carbon dioxide-carbonized solid waste material; (2) uniformly mixing the carbon dioxide-carbonized solid waste material and the sulphoaluminate cement in a certain proportion to obtain a solid waste-based cementitious material.

[0022] Further, the carbon dioxide-carbonized solid waste material and the sulphoaluminate cement are stored after being mixed in advance; or the carbon dioxide-carbonized solid waste material and the sulphoaluminate cement are stored separately and mixed when used.

[0023] Further, the mixing method is one of manual stirring mixing, mixer stirring mixing, and ball mill mixing.

[0024] The present application has the following advantages: 1) The present application carbonizes the solid waste material by using carbon dioxide and then mixes the carbon dioxide-carbonized solid waste material with sulphoaluminate cement to obtain a solid waste-based cementitious material, which not only effectively stores carbon dioxide and absorbs solid waste material, but also optimizes the hydration product composition of the sulphoaluminate cement, fully utilizes the activity of the solid waste material, and greatly improves the reaction efficiency of the mixed material.

[0025] 2) The application proposes a proportioning formula of carbonated solid waste material and sulphoaluminate cement, and the two are proportioned according to the proportioning formula, so that the carbonated solid waste material can be used more scientifically, and specific chemical reactions occur between the uncarbonated calcium silicate, calcium carbonate formed after carbonation and aluminum components in the solid waste material and the sulphoaluminate cement, to generate target products such as C-S-H gel, single-carbon hydrated calcium aluminum (iron) carbonate, single-sulfur hydrated sulphoaluminate (iron) calcium, and three-sulfur hydrated sulphoaluminate (iron) calcium, so as to reduce the components such as free calcium oxide in the solid waste material which are not conducive to the performance of products (such as concrete, building material products, etc.), and fully utilize the carbonated solid waste material, and the generated products improve the strength of the material, making up for the strength loss caused by directly adding solid waste to cement-based materials.

[0026] (3) The application is not limited to the carbonation method of solid waste material, and dry direct carbonation, wet direct carbonation and carbonation during grinding are all applicable, and the applicability is wide, without the need for specific equipment modification. DETAILED DESCRIPTION

[0027] In order to make the above-mentioned purposes, features and advantages of the application more obvious and easy to understand, the specific embodiments of the application are described in detail below. In the following description, a large number of specific details are set forth in order to fully understand the application. However, the application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the concept of the application, so the application is not limited by the specific examples disclosed below.

[0028] Except as shown in the working examples or otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, reaction, and so forth used in the specification and claims are to be understood as being modified in all instances by the term "about." Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by those skilled in the art utilizing the teachings of the present disclosure. At the very least, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Numerical ranges include all numerical values and ranges between the numbers "from" and "to" provided. For example, a range from 1 to 5 includes 1, 1.1, 1.2, 1.3, 1.4, 1.5, 2, 2.75, 3, 3.80, 4, and 5, etc.

[0029] An embodiment of the application provides a solid waste-based cementitious material prepared by using carbonated solid waste material, and the preparation raw materials include, by weight: carbonated solid waste material In some embodiments, the content of calcium oxide in the solid waste material before carbonation treatment is not less than 10%.

[0030] In some embodiments, the solid waste material is one or more of steel slag, carbide slag, fly ash, municipal solid waste incineration ash, magnesium slag, phosphorous slag, red mud.

[0031] In some embodiments, the steel slag is one or more of converter steel slag, electric furnace steel slag, open hearth steel slag, refining steel slag.

[0032] In some embodiments, the carbide slag is one or both of dry carbide slag and wet carbide slag.

[0033] In some embodiments, the fly ash is one or both of high calcium fly ash and low calcium fly ash.

[0034] In some embodiments, the magnesium slag is metallurgical slag generated in the production process of magnesium metal and magnesium products.

[0035] In some embodiments, the phosphorous slag is molten waste slag with calcium silicate as the main component obtained in the process of producing yellow phosphorus by using phosphorus ore thermal method.

[0036] In some embodiments, the red mud is one or more of Bayer process red mud, sintering process red mud, and combined process red mud.

[0037] In some embodiments, the carbonization treatment method is selected from one of dry direct carbonization, wet direct carbonization, and carbonization in the grinding process.

[0038] In some embodiments, the dry direct carbonization is a direct reaction of carbon dioxide with the solid waste material under a set environmental humidity, a set pressure, and a set temperature.

[0039] In some embodiments, the dry direct carbonization is to place the dry powder raw material directly in a high-temperature and high-pressure reaction kettle without mixing with water, and then use a vacuum pump to pump the gas pressure in the reaction kettle to below 0.01 bar, and then heat the reaction kettle at a rate of 10°C / min, and then introduce a CO2-containing gas without water when the temperature is above 600°C, so that the final temperature in the reaction kettle is >600°C, the gas pressure is >100 bar, and the environmental humidity is <5% RH.

[0040] In some embodiments, the wet direct carbonization is a reaction of carbon dioxide dissolved in water with the solid waste material under a set environmental humidity, a set pressure, and a set temperature.

[0041] In some embodiments, the wet direct carbonization is to mix the dry powder with water to ensure that the water-solid ratio is >0.1, and then place the wet powder in an atmospheric pressure reaction container, and then introduce a CO2-containing gas at a rate of >10 mL / min, and the environmental humidity can be controlled by introducing water vapor or placing a potassium sulfate solution in the reaction container during the reaction process, so that the final temperature in the reaction container is >0°C, the gas pressure is 1 bar, and the environmental humidity is >5% RH.

[0042] In some embodiments, the carbonation during grinding is a carbonation reaction of the solid waste material with carbon dioxide during grinding of the solid waste material.

[0043] In some embodiments, the carbonation during grinding is that the raw material is ground to a particle size of <0.1 mm by a ball mill, a vertical powder mill, a Raymond mill, etc., and a CO2-containing gas is introduced at a rate of >10 mL / min during the grinding process. Water can be added during the reaction process to control the environmental humidity, so that the final reaction environment temperature is >0℃, the gas pressure is 1 bar, and the humidity is >5% RH.

[0044] In some embodiments, the environmental humidity of the dry direct carbonation is below 5%.

[0045] In some embodiments, the environmental humidity of the wet direct carbonation is above 5%.

[0046] In some embodiments, the solid waste material carbonated by carbon dioxide has a 45 μm square hole screen residue of not more than 50%.

[0047] Sulphoaluminate cement In some embodiments, the sulphoaluminate cement has a 45 μm square hole screen residue of not more than 50%.

[0048] In some embodiments, it is one or more of fast-hardening sulphoaluminate cement, low-alkalinity sulphoaluminate cement, self-stressing sulphoaluminate cement, and sulphoaluminate cement clinker.

[0049] In some embodiments, the method for preparing a solid waste-based cementitious material using carbonated solid waste material comprises the following steps: (1) carbonating the solid waste material using a carbon dioxide-containing gas to obtain a solid waste material carbonated by carbon dioxide; (2) mixing the solid waste material carbonated by carbon dioxide and sulphoaluminate cement in a proportion to obtain a solid waste-based cementitious material.

[0050] Embodiments The following examples more specifically describe the disclosure, which are merely illustrative and are not intended to limit the scope of the disclosure, as various modifications and variations can be apparent to those skilled in the art. Unless otherwise stated, all parts, percentages, and ratios reported in the following examples are by weight, and all reagents used in the examples are commercially available or synthesized according to conventional methods and used as received without further purification, and the instruments used in the examples are commercially available.

[0051] According to the test analysis by an X-ray fluorescence spectrometer, the carbonated steel slag and cement clinker ingredient contents used in the following examples are shown in Table 1: Table 1 Chemical composition of carbonized steel slag, cement clinker (mol%) The carbonization method used in the examples is wet direct carbonization, and the preparation method of the carbonized steel slag (solid waste material treated by carbonization of carbon dioxide) is as follows: S1, vacuum drying and grinding the converter slag to 45 μm square hole sieve residue not more than 50%; S2, the ground converter slag is mixed with water in a ratio of 1:10 and stirred uniformly, carbonization reaction is carried out by introducing carbon dioxide containing gas with a flow rate of 100 mL / min in the solution, the reaction temperature is room temperature, and the reaction time is 2 h; S3, after the carbonization reaction is completed, the carbonized steel slag is filtered and dried to obtain the carbonized steel slag.

[0052] In the above step S2, the volume content of CO2 in the carbon dioxide containing gas is more than 99.99%. In actual production, the carbon dioxide containing gas used can be commercially available high-purity carbon dioxide gas, or industrial flue gas can be directly used, and the volume content of carbon dioxide in the carbon dioxide containing gas is more than 30%.

[0053] Determination of the carbonization reaction degree η of solid waste: The amount of calcium carbonate generated after carbonization for 3 hours, 6 hours, 12 hours, 24 hours, 36 hours and 48 hours is measured by thermal gravimetric analysis, and it is found that the amount of calcium carbonate generated after carbonization for 48 hours no longer increases, at which time the carbonization is considered complete and the carbonization reaction is stable. When the carbonation of calcium carbonate is stopped at half of the stable time, the carbonization degree η is 0.5 (measured by thermal gravimetric analysis, the carbonization time is 2 h, and the carbonation of calcium carbonate is stopped at half of the stable time).

[0054] When the X-ray fluorescence spectrometer test analysis result tests the chemical composition of more than 92% of the material, the test result can be directly used for the following calculation.

[0055] The molar mass of the carbonized steel slag is: (41.5x56+5.3x56+15.0x60+4.1x102+6.2x40+22.5x160+0.1x80) / 94.7=82 The molar mass of the cement clinker is: (56.76x56+23.21x60+9.03x102+4.86x80) / 93.86=63 The carbonized steel slag with a carbonization degree η of 0.5 is used in the following examples for testing, and according to the solid waste based cementitious material proportioning design method proposed by the present application, the mass percentage of steel slag in the solid waste based cementitious material is W 钢渣 W 钢渣and the raw material chemical composition data, η value, molar mass of the steel slag and cement shown in Table 1 are substituted into the formula: (1) 1 / 3 x (W 钢渣 x 0.001 / 82 + (1-W 钢渣 ) x 0.0486 / 63) + 1 / 2 x 0.5 x W 钢渣 x (0.415 + 0.053) / 82 ≤ W 钢渣 x 0.041 / 82 + (1-W 钢渣 ) x 0.0903 / 63 ≤ 0.5 x W 钢渣 x (0.415 + 0.053) / 82 + W 钢渣 x 0.001 / 82 + (1-W 钢渣 ) x 0.0486 / 63 (2) W 钢渣 x 0.150 / 82 + (1-W 钢渣 ) x 0.2321 / 63 + 2 x 0.5 x W 钢渣 x (0.415 + 0.053) / 82 + 2 x W 钢渣 x 0.001 / 82 + 2 x (1-W 钢渣 ) x 0.0486 / 63 ≤ W 钢渣 x (0.415 + 0.053) / 82 + (1-W 钢渣 ) x 0.5676 / 63 ≤ 2 x W 钢渣 x 0.150 / 82 + 2 x (1-W 钢渣 ) x 0.2321 / 63 + 4 x 0.5 x W 钢渣 x (0.415 + 0.053) / 82 + 4 x W 钢渣 x 0.001 / 82 + 4 x (1-W 钢渣 ) x 0.0486 / 63 After calculation: (1) 22% ≤ W 钢渣 ≤ 56% (2) -18% ≤ W 钢渣 ≤ 67% Combining formula (1) and formula (2), 22% ≤ W 钢渣 ≤ 56% is obtained.

[0056] Example 1 The present example provides a solid waste-based cementitious material prepared by using carbonized solid waste material, and the raw material composition is: 25 kg of carbonized steel slag and 75 kg of sulphoaluminate cement clinker.

[0057] The above carbonized steel slag and sulphoaluminate cement clinker are mixed uniformly to obtain a solid waste-based cementitious material.

[0058] Example 2 The present embodiment provides a solid waste-based cementitious material prepared by using carbonized solid waste material, and the raw material composition is: 30 kg of carbonized steel slag and 70 kg of sulphoaluminate cement clinker.

[0059] The above carbonized steel slag and sulphoaluminate cement clinker are mixed uniformly to obtain a solid waste-based cementitious material.

[0060] Example 3 The present embodiment provides a solid waste-based cementitious material prepared by using carbonized solid waste material, and the raw material composition is: 40 kg of carbonized steel slag and 60 kg of sulphoaluminate cement clinker.

[0061] The above carbonized steel slag and sulphoaluminate cement clinker are mixed uniformly to obtain a solid waste-based cementitious material.

[0062] Example 4 The present embodiment provides a solid waste-based cementitious material prepared by using carbonized solid waste material, and the raw material composition is: 50 kg of carbonized steel slag and 50 kg of sulphoaluminate cement clinker.

[0063] The above carbonized steel slag and sulphoaluminate cement clinker are mixed uniformly to obtain a solid waste-based cementitious material.

[0064] Comparative Example 1 The present comparative example provides a solid waste-based cementitious material prepared by using carbonized solid waste material, and the raw material composition is: 10 kg of carbonized steel slag and 90 kg of sulphoaluminate cement clinker.

[0065] The above carbonized steel slag and sulphoaluminate cement clinker are mixed uniformly to obtain a solid waste-based cementitious material.

[0066] Comparative Example 2 The present comparative example provides a solid waste-based cementitious material prepared by using carbonized solid waste material, and the raw material composition is: 60 kg of carbonized steel slag and 40 kg of sulphoaluminate cement clinker.

[0067] The above carbonized steel slag and sulphoaluminate cement clinker are mixed uniformly to obtain a solid waste-based cementitious material.

[0068] Comparative Example 3 The raw material composition of the present comparative example is: 100 kg of sulphoaluminate cement clinker.

[0069] Product Example The solid waste-based cementitious materials prepared in Examples 1-4 and Comparative Examples 1-3 are respectively used to prepare concrete, and the concrete mix proportion is: 380 kg / m 3 of solid waste-based cementitious material, 1070 kg / m 3 of stone, 660 kg / m 3 of sand, and 1 kg / m of water reducing agent.3 water 190 kg / m 3 .

[0070] The water-reducing agent is a polycarboxylate-type water-reducing agent with a water-reducing rate of 30%; the yellow sand meets the relevant provisions in GB / T 14684-2011 “Sand for Construction” and has a particle size gradation belonging to a two-zone gradation distribution; and the stone meets the relevant provisions in GB / T 14685-2022 “Ovule and Rubble for Construction” and has a continuous particle size distribution of 5-25 mm.

[0071] Test examples The 7-day and 28-day compressive strengths of the concrete prepared by using the solid waste-based cementitious materials in Examples 1-4 and Comparative Examples 1-3 were tested, and the test results are shown in Table 1. Among them: According to GB / T 50081-2002 “Standard for Testing Methods of Mechanical Properties of Ordinary Concrete”, the 7-day and 28-day compressive strengths of the concrete were tested: the mixed concrete was formed in a 10 cm cubic mold, demolded after 24 hours, and cured under standard conditions to the corresponding age, and the compressive strength of the concrete was tested using a pressure testing machine.

[0072] Table 2 Test results of the compressive strength of the concrete As can be seen from Table 1, the solid waste-based cementitious materials prepared by using the carbonated solid waste material and the sulphoaluminate cement according to the present application (Examples 1-4) have significantly higher long-term strength performance than the comparative examples 1-3 which do not meet the preferred ratio. This shows that under the preferred ratio, the carbonated solid waste and the sulphoaluminate cement in the material can indeed produce good chemical reactions and stimulate the potential activity of the solid waste. Since the solid waste is widely available and low in price, the sulphoaluminate composite cement prepared by using the carbonated solid waste material according to the present application has good performance and low cost, and has a broad market prospect.

[0073] The present application is described by the above examples to illustrate the detailed process equipment and process flow of the present application, but the present application is not limited to the above detailed process equipment and process flow, i.e. it does not mean that the present application must rely on the above detailed process equipment and process flow to be implemented. Those skilled in the art should understand that any improvement of the present application, equivalent replacement of each raw material of the product of the present application, variation of the structure form, addition of auxiliary ingredients, selection of specific modes, etc. fall within the scope of protection and disclosure of the present application.

[0074] The preferred embodiments of the present application are described in detail above, but the present application is not limited to the specific details described above. Various simple modifications can be made to the technical solutions of the present application within the scope of the technical concept of the present application, and all of these simple modifications belong to the protection scope of the present application.

[0075] In addition, it should be noted that each specific technical feature described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, various possible combinations are not described again by the present application.

[0076] In addition, various different embodiments of the present application can also be combined in any manner as long as they do not contradict the idea of the present application, and they should also be considered as disclosed by the present application.

[0077] The above embodiments are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and implement it, and it cannot limit the protection scope of the present application. Any equivalent changes or modifications made according to the spirit and essence of the present application should be covered within the protection scope of the present application.

Claims

1. A solid waste-based cementitious material prepared using carbonized solid waste materials, characterized in that, This includes solid waste materials treated with carbon dioxide and sulfoaluminate cement.

2. The solid waste-based cementitious material prepared using carbonized solid waste materials according to claim 1, characterized in that, The ratio of the solid waste material treated with carbon dioxide carbonization to the sulfoaluminate cement satisfies the following formula: (1)1 / 3×(n SS,SO3 + n CSA,SO3 ) + 1 / 2η×n SS,CaO ≤ n SS,Al2O3 + n CSA,Al2O3 ≤η×n SS,CaO +n SS,SO3 + n CSA,SO3 (2)n SS,SiO2 + n CSA,SiO2 + 2η×n SS,CaO + 2×(n SS,SO3 + n CSA,SO3 )≤n SS,CaO + n CSA,CaO ≤ 2×(n SS,SiO2 + n CSA,SiO2 ) + 4η×n SS,CaO + 4×(n SS,SO3 + n CSA,SO3 ) Where, n SS,SO3 n SS,CaO n SS,Al2O3 n SS,SiO2 These are the molar masses of sulfate, calcium oxide, aluminum oxide, and silicon oxide in solid waste materials treated with carbon dioxide carbonization; n CSA,SO3 n CSA,CaO n CSA,Al2O3 n CSA,SiO2 η represents the molar mass of sulfate, calcium oxide, aluminum oxide, and silicon oxide in sulfoaluminate cement, respectively; η is the degree of carbonization reaction of solid waste.

3. The solid waste-based cementitious material prepared using carbonized solid waste materials according to claim 1, characterized in that, The calcium oxide content in the solid waste material is not less than 10%.

4. The solid waste-based cementitious material prepared using carbonized solid waste materials according to claim 1, characterized in that, The solid waste material is one or more of the following: steel slag, carbide slag, fly ash, municipal solid waste incineration ash, magnesium slag, phosphate rock slag, and red mud.

5. The solid waste-based cementitious material prepared using carbonized solid waste materials according to claim 4, characterized in that, The steel slag is one or more of the following: converter steel slag, electric furnace steel slag, open-hearth furnace steel slag, and refined steel slag; The carbide slag is one or both of dry carbide slag and wet carbide slag. The fly ash is one or both of high-calcium fly ash and low-calcium fly ash; The magnesium slag is a metallurgical waste slag generated during the production of metallic magnesium and magnesium products. The phosphate slag is the waste residue mainly composed of calcium silicate obtained during the thermal process of producing yellow phosphorus from phosphate rock. The red mud is one or more of the Bayer process red mud, sintering process red mud, and combined process red mud.

6. The solid waste-based cementitious material prepared using carbonized solid waste materials according to claim 1, characterized in that, The carbonization treatment method is selected from one of dry direct carbonization, wet direct carbonization, and carbonization during grinding. The dry direct carbonization involves reacting carbon dioxide directly with solid waste materials under set environmental humidity, pressure, and temperature; the wet direct carbonization involves dissolving carbon dioxide in water under set environmental humidity, pressure, and temperature, and then reacting it with solid waste materials; the carbonization during grinding involves causing carbon dioxide to react with solid waste materials during the grinding process.

7. The solid waste-based cementitious material prepared using carbonized solid waste materials according to claim 6, characterized in that, The ambient humidity for dry direct carbonization is below 5%; the ambient humidity for wet direct carbonization is above 5%.

8. The solid waste-based cementitious material prepared using carbonized solid waste materials according to claim 1, characterized in that, The solid waste material and sulfoaluminate cement treated with carbon dioxide are in powder form and meet the requirement that the residue on a 45μm square hole sieve does not exceed 50%.

9. The solid waste-based cementitious material prepared using carbonized solid waste materials according to claim 1, characterized in that, The sulfoaluminate cement is one or more of the following: rapid-hardening sulfoaluminate cement, low-alkalinity sulfoaluminate cement, self-stressing sulfoaluminate cement, and sulfoaluminate cement clinker.

10. A method for preparing a solid waste-based cementitious material using carbonized solid waste materials as described in any one of claims 1-9, characterized in that, Includes the following steps: (1) Carbonize solid waste materials with carbon dioxide-containing gas to obtain solid waste materials treated with carbon dioxide carbonization. (2) Mix solid waste materials treated with carbon dioxide carbonization and sulfoaluminate cement in proportion to obtain solid waste-based cementitious materials.

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