Low-carbon premixed concrete based on industrial solid waste synergistic activation and preparation method thereof

Abstract

The invention provides low-carbon premixed concrete based on industrial solid waste synergistic activation and a preparation method of the low-carbon premixed concrete. The low-carbon premixed concrete is prepared from the following components: a nano silicon-based anti-corrosion early strength agent, a cementing material, recycled aggregate, electric furnace tailings, waste carbon fibers, a polycarboxylate superplasticizer and water, the preparation method comprises the following steps: S1, preparing a nano silicon-based anti-corrosion early strength agent through silane hydrolysis and modification reaction of nano silicon dioxide; s2, preparing a cementing material: mixing fly ash, steel slag, mineral slag and Portland cement, calcining, grinding, spraying a composite alkali activator, and aging; s3, mixing and forming: wet-mixing the cementing material, the recycled aggregate, the iron tailing sand, the waste fibrilia, the nano silicon-based anti-corrosion early strength agent, the polycarboxylate superplasticizer and water, and pre-injecting and forming; and S4, carbonization curing. According to the invention, efficient utilization of industrial solid waste is realized, and the low-carbon environmental protection performance and mechanical property of the concrete are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete, and particularly relates to a low-carbon premixed concrete based on the synergistic activation of industrial solid wastes and a preparation method thereof. Background Art

[0002] Cement is the core gelling material of traditional concrete. Its production accounts for about 8% of the global carbon dioxide emissions. For every 1 ton of cement produced, about 0.6 - 0.8 tons of carbon dioxide are emitted. Moreover, the clinker calcination process (accounting for 60% of cement carbon emissions) relies on high-temperature fossil fuels, and it is difficult to reduce carbon emissions through conventional processes. With global climate change and increasingly scarce resources, the construction industry, as a high-energy-consuming and high-emission field, is facing unprecedented environmental protection pressures. As the cornerstone of the construction industry, the production process of concrete not only consumes a large amount of natural resources but also generates a large amount of waste, causing serious impacts on the environment. Therefore, the development of a low-carbon premixed concrete based on the synergistic activation of industrial solid wastes and a preparation method thereof is not only an important measure to respond to the national call for energy conservation and emission reduction but also a key way to achieve the green and sustainable development of the construction industry.

[0003] Industrial solid wastes, such as steel slag, fly ash, desulfurized gypsum, etc., are wastes generated during industrial production processes. If these wastes are not properly treated, they will not only occupy land resources but may also pollute the surrounding environment. However, these solid wastes often contain certain potential values. For example, through scientific and reasonable treatment, they can be transformed into building materials to achieve the reuse of resources. In recent years, with the progress of technology and the improvement of environmental protection awareness, the comprehensive utilization of industrial solid wastes has become a research hotspot.

[0004] A preparation technology for low-carbon premixed concrete based on the synergistic activation of industrial solid wastes has emerged under this background. This technology pre-treats and activates industrial solid wastes to make them have higher reaction activities and better physical and mechanical properties, so that they can be used as the main raw materials or admixtures of concrete. This kind of concrete not only has low costs but also has excellent environmental protection performance, can effectively reduce carbon emissions, and reduce environmental pollution.

[0005] During the preparation process, it is first necessary to pre-treat industrial solid wastes, including steps such as crushing, screening, and impurity removal, to improve their utilization rate and reaction activity. Subsequently, by adding specific activators, such as chemical activators, physical activators, etc., the potential active components in the solid wastes are further stimulated to chemically react with other components in the concrete to form a more compact structure.

[0006] In addition to the co-activation of industrial solid wastes, the preparation of low-carbon ready-mixed concrete also needs to consider other factors, such as the selection of raw materials, the design of mix proportion, the control of the production process, etc. In the selection of raw materials, environmentally friendly and renewable materials should be preferred, such as recycled aggregates, green high-performance admixtures, etc. In the design of mix proportion, reasonable collocation needs to be carried out according to engineering requirements and material properties to ensure that the strength and durability of the concrete meet the requirements. During the production process, management and monitoring need to be strengthened to ensure energy conservation, emission reduction and product quality in the production process.

[0007] Shenzhen is divided into four regions: the coastal area, the urban area, the suburban area and the mountainous area. The environmental characteristics of each region are different, and the requirements for concrete are also different. For example, the high salinity and humidity in the coastal area, chemical corrosion and mechanical loads in the urban area, freeze-thaw damage in the suburban area, heavy rain and geological disasters in the mountainous area, etc. The high chloride ions and salt mist in the coastal area will accelerate the corrosion of steel bars, especially for projects such as cross-sea bridges, where higher durability requirements for concrete are needed.

[0008] In summary, a low-carbon ready-mixed concrete based on the co-activation of industrial solid wastes and its preparation method is a green building material technology with broad application prospects. The market is in urgent need of a low-carbon ready-mixed concrete based on the co-activation of industrial solid wastes and its preparation method, which can not only realize the resource utilization of industrial solid wastes, reduce environmental pollution and carbon emissions, but also improve the performance of concrete and reduce costs, providing strong support for the sustainable development of the construction industry, and is particularly suitable for application in the coastal area with high salinity and humidity. Summary of the Invention

[0009] The present invention provides a low-carbon ready-mixed concrete based on the co-activation of industrial solid wastes and its preparation method to solve the problems raised in the above-mentioned background technology.

[0010] To solve the above technical problems, the present invention discloses a low-carbon ready-mixed concrete based on the co-activation of industrial solid wastes, comprising the following components: nano-silicon-based anti-corrosion early-strength agent, cementitious material, recycled aggregate, electric furnace tailings, carbon fiber waste filaments, polycarboxylate water reducer and water.

[0011] Further, by weight, it comprises the following components: 0.8-1.2 parts of nano-silicon-based anti-corrosion early-strength agent, 95-110 parts of cementitious material, 780-850 parts of recycled aggregate, 185-210 parts of electric furnace tailings, 0.1-0.3 parts of carbon fiber waste filaments, 1.43-1.65 parts of polycarboxylate water reducer and 30-36 parts of water.

[0012] Further, the nano-silicon-based anti-corrosion early strength agent, by weight, comprises the following components: 30 parts of deionized water, 8 parts of calcium nitrate, 12 parts of MCI-2020, 0.5 part of PEG-6000, 1 part of sodium gluconate, 4 parts of modified nano-silica powder, 0.5 part of sulphoaluminate cement clinker and 1.2 parts of air-entraining agent.

[0013] Further, the modified nano-silica powder, by weight, comprises the following components: 5 parts of KH-550, 30 parts of deionized water and 35 parts of nano-silica.

[0014] Further, the preparation method of the modified nano-silica powder comprises: mixing 5 parts of KH-550 with 30 parts of deionized water, adjusting the pH to 5.0 with acetic acid, heating to 50 °C, stirring at 500 rpm for 1 hour to fully hydrolyze the silane to form silanol, adding 35 parts of nano-silica, heating to 70 °C, shearing at 8000 rpm for 8000 rpm and holding for reaction for 4 hours, and spray drying to obtain the modified nano-silica powder.

[0015] Further, the preparation method of the nano-silicon-based anti-corrosion early strength agent comprises: adding 8 parts of calcium nitrate, 12 parts of MCI-2020, 0.5 part of PEG-6000 and 1 part of sodium gluconate to 30 parts of deionized water, stirring at 400 rpm for 2 hours, adding 4 parts of modified nano-silica powder, 0.5 part of sulphoaluminate cement clinker and 1.2 parts of air-entraining agent, stirring at 150 rpm for 1 hour, passing through a high-pressure homogenizer at a pressure of 60 MPa, circulating 3 times to refine the particles, and passing through a 200-mesh sieve to obtain the nano-silicon-based anti-corrosion early strength agent.

[0016] Further, the preparation method of low-carbon ready-mixed concrete based on the synergistic activation of industrial solid waste comprises:

[0017] S1. Preparing the nano-silicon-based anti-corrosion early strength agent;

[0018] S2. Preparing the cementitious material;

[0019] S3. Mixing the nano-silicon-based anti-corrosion early strength agent prepared in step S1, the cementitious material prepared in step S2, recycled aggregate, electric furnace tailings, carbon fiber waste filaments, polycarboxylate water reducer and water, and then forming;

[0020] S4. Performing carbonization curing on the formed concrete.

[0021] Further, the preparation method of the cementitious material includes: mixing fly ash, steel slag, slag and portland cement, calcining at low temperature and grinding, spraying a composite alkali activator, adding Feitong granular silicon and aging to obtain the cementitious material; in the preparation of the cementitious material, the addition amounts of fly ash, steel slag, slag and portland cement are 25 parts, 15 parts, 10 parts and 20 parts respectively; the low-temperature calcination temperature is 550°C, and it is ground to a specific surface area of 550 m 2 / kg; the composite alkali activator is composed of 40% sodium silicate, 30% sodium sulfate and 30% citric acid.

[0022] Further, in the mixing and forming step, the addition amounts of the cementitious material, recycled aggregate, electric furnace tailings, carbon fiber waste filaments, nano-silicon-based anti-corrosion early strength agent, polycarboxylate water reducer and water are 100 parts, 800 parts, 200 parts, 0.2 part, 1 part, 1.5 parts and 30 parts respectively by weight; wet mix until the slump is 175 - 183 mm, and use high-pressure extrusion to pre-form at 15 MPa with 10% concentration CO2.

[0023] Further, in the carbonization curing step, pass 20% concentration CO2 at 0.1 MPa for 6 hours, the carbonization depth is 8 mm, and cure under standard conditions for 25 - 30 days.

[0024] Compared with the prior art, the present invention provides a low-carbon ready-mixed concrete based on the synergistic activation of industrial solid wastes and its preparation method, having the following beneficial effects:

[0025] 1. Through the synergistic activation technology, the present invention effectively utilizes industrial solid wastes (such as fly ash, slag, furnace slag, etc.). These solid wastes were originally regarded as waste, but now they are transformed into part of the concrete material, which not only reduces the accumulation of solid wastes and environmental pollution, but also realizes the recycling of resources. This technology helps to reduce the exploitation of natural resources and the damage to the environment, meeting the concept of sustainable development;

[0026] 2. Nano-silica reacts quickly with the cementitious material to generate C-S-H gel, and the strength is increased by 30% in 3 days. Nano-silicon-based particles fill the pores and form a dense protective layer, reducing the chloride ion permeability. Nano-SiO2 and microalgal calcium carbonate in the bio-cement jointly optimize the pore structure;

[0027] 3. Due to the extensive use of industrial solid wastes as raw materials, the demand for high-carbon emission materials such as traditional cement is reduced, thus significantly reducing the carbon emissions during the concrete production process. The synergistic activation technology also reduces the carbon footprint during the use of concrete (such as carbon emissions during the hardening process) by optimizing the concrete mix ratio and performance, achieving low-carbon environmental protection throughout the life cycle;

[0028] 4. After certain components in industrial solid waste are synergistically activated, the physical and mechanical properties of concrete can be significantly improved, such as enhancing strength, durability, crack resistance, etc. By precisely controlling the activation process and ratio, concrete that meets specific engineering requirements can be customized, such as high-strength, self-compacting, lightweight and other high-performance concretes. Detailed implementation manners

[0029] The following describes the preferred embodiments of the present invention. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0030] In addition, in the present invention, descriptions such as "first" and "second" are only for descriptive purposes, and do not particularly refer to the meaning of order or sequence, nor are they used to limit the present invention. They are only used to distinguish components or operations described with the same technical terms, and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions and technical features between various embodiments can be combined with each other, but it must be based on the fact that those skilled in the art can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0031] Unless otherwise specified, the examples and comparative examples are parallel tests with the same components, component contents, preparation steps, and preparation parameters. The experimental methods in the following examples are all conventional methods unless otherwise specified; the test materials used in the following examples are all analytical reagents (A.R.) and are purchased from commercial channels.

[0032] Nano-silica, Hubei Huifu Nano Materials Co., Ltd., HL200; Feitong granular silicon was purchased from Aigelu International Agricultural Science and Technology Co., Ltd. It is processed by fermenting silicate bacteria and Bacillus amyloliquefaciens selected over the years, with natural clinoptilolite as the carrier. Silicon ≥ 60%, potassium ≥ 2.9%, calcium ≥ 3.4%, magnesium ≥ 0.7%, iron ≥ 1%, peptide ≥ 0.2%; The effective strain is Bacillus amyloliquefaciens, and the effective viable count ≥ 200 million / g; Recycled bone was purchased from Beijing Jingyu Lu Construction Engineering Co., Ltd., 100 mesh; Electric furnace tailings were purchased from Yunnan Huachen Environmental Protection Technology Co., Ltd. The electric furnace tailings No. 7 quartz sand is 80 mesh, with a porosity of 43.04% and a wear rate of 0.035; Carbon fiber waste filaments were purchased from Jusheng Carbon Fiber (Guangdong) Co., Ltd., T700, with a compressive strength of 3530 MPA, produced in Japan; Polycarboxylate superplasticizer was purchased from Jiangsu Sobute New Materials Co., Ltd.; Air-entraining agent was purchased from Shandong Kunxiang Chemical Technology Co., Ltd.; MCI-2020 was purchased from Shenzhen Feng'an Technology Co., Ltd.; Polyethylene glycol PEG-6000 is a Dow brand, with a hydroxyl value of 170 - 208 KOH / g.

[0033] Example 1

[0034] S1. Preparation of nano-silicon-based anti-corrosion early-strength agent: Mix 5 parts of KH-550 with 30 parts of deionized water, adjust the pH to 5.0 with acetic acid, heat up to 50 °C, stir at 500 rpm for 1 hour to fully hydrolyze the silane to form silanol, add 35 parts of nano-silica, heat up to 70 °C, shear at 8000 rpm for 8000 rpm and keep the reaction for 4 hours, and spray dry to obtain modified nano-silica powder. Add 8 parts of calcium nitrate, 12 parts of MCI-2020, 0.5 part of PEG-6000 and 1 part of sodium gluconate to 30 parts of deionized water, stir at 400 rpm for 2 hours, add 4 parts of modified nano-silica powder, 0.5 part of sulfoaluminate cement clinker and 1.2 parts of air-entraining agent, stir at 150 rpm for 1 hour, pass through a high-pressure homogenizer at a pressure of 60 MPa, circulate 3 times to refine the particles, and pass through a 200-mesh sieve to obtain nano-silicon-based anti-corrosion early-strength agent (NS-CRA).

[0035] S2. Preparation of cementitious material: Mix 25 parts of fly ash, 15 parts of steel slag, 10 parts of slag and 20 parts of P·O42.5 portland cement, calcine at 550 °C at low temperature and grind to a specific surface area of 550 m 2 / kg; Spray 5 parts of composite alkali activator (40% sodium silicate, 30% sodium sulfate and 30% citric acid), add 0.5 part of Feitong granular silicon and age at 35 °C and 75% humidity for 24 hours to obtain the cementitious material.

[0036] S3, Mixing and Molding: 100 parts of cementitious materials, 800 parts of recycled aggregates, and 200 parts of electric furnace tailings are put into a twin-shaft mixer. Add 0.2 parts of carbon fiber waste filaments, 1 part of nano-silicon-based anti-corrosion and early-strength agent, 1.5 parts of polycarboxylate water reducer, and 30 parts of water. Wet mix until the slump reaches 180 mm, and use high-pressure extrusion to pre-mold with 10% concentration CO2 at 15 MPa to generate calcium carbonate to enhance the interfacial bonding.

[0037] S4, Carbonation Curing: After molding, pass 20% concentration CO2 at 0.1 MPa for 6 hours of curing, with a carbonation depth of 8 mm, and standard curing for 28 days to obtain a low-carbon ready-mixed concrete based on the synergistic activation of industrial solid wastes.

[0038] Example 2

[0039] S3, Mixing and Molding: 95 parts of cementitious materials, 780 parts of recycled aggregates, and 185 parts of electric furnace tailings are put into a twin-shaft mixer. Add 0.1 parts of carbon fiber waste filaments, 0.8 parts of nano-silicon-based anti-corrosion and early-strength agent, 1.43 parts of polycarboxylate water reducer, and 31 parts of water. Wet mix until the slump reaches 175 mm, and use high-pressure extrusion to pre-mold with 10% concentration CO2 at 15 MPa to generate calcium carbonate to enhance the interfacial bonding.

[0040] Example 3

[0041] S3, Mixing and Molding: 110 parts of cementitious materials, 850 parts of recycled aggregates, and 210 parts of electric furnace tailings are put into a twin-shaft mixer. Add 0.3 parts of carbon fiber waste filaments, 1.2 parts of nano-silicon-based anti-corrosion and early-strength agent, 1.65 parts of polycarboxylate water reducer, and 36 parts of water. Wet mix until the slump reaches 183 mm, and use high-pressure extrusion to pre-mold with 10% concentration CO2 at 15 MPa to generate calcium carbonate to enhance the interfacial bonding.

[0042] Comparative Example 1

[0043] The difference from Example 1 is the lack of an equal weight portion of nano-silicon-based anti-corrosion and early-strength agent, and the others are the same.

[0044] Comparative Example 2

[0045] The difference from Example 1 is the lack of an equal weight portion of Feitong granular silicon, and the others are the same.

[0046] Comparative Example 3

[0047] The difference from Example 1 is the lack of an equal weight portion of sulphoaluminate cement clinker, and the others are the same.

[0048] Comparative Example 4

[0049] The difference from Example 1 is that an equal weight portion of modified nano-silica is replaced with ordinary nano-silica, and the others are the same.

[0050] Comparative Example 5

[0051] It is different from Example 1 in that it lacks an air-entraining agent in equal weight parts, and the others are the same.

[0052] Comparative Example 6

[0053] It is different from Example 1 in that it uses Bacillus amyloliquefaciens of a single strain in equal weight parts to replace Feitong granular silicon, and the others are the same.

[0054] Comparative Example 7

[0055] It is different from Example 1 in that it lacks carbon fiber waste filaments in equal weight parts, and the others are the same.

[0056] Comparative Example 8

[0057] It is different from Example 1 in that it lacks electric furnace tailings in equal weight parts, and the others are the same.

[0058] Performance Test

[0059] The concrete prepared in the examples and comparative examples was subjected to compressive strength, chloride ion diffusion and salt spray tests. The compressive strength was measured according to the ISO 679 standard, and the chloride ion diffusion was measured by the RCM method. The results are shown in Table 1.

[0060] Table 1

[0061]

[0062]

[0063] As can be seen from Table 1, the nano-silica-based early strength agent, Feitong granular silicon, electric furnace tailings and carbon fiber waste filaments have a synergistic effect. The effect of Example 1 is the best. In Comparative Example 2, due to the lack of Feitong granular silicon, the 3-day compressive strength decreased, the 28-day compressive strength decreased, the chloride ion diffusion coefficient increased, and the steel bar corrosion rate increased. This comparison verifies the irreplaceability of Feitong granular silicon in the synergistic activation of industrial solid waste systems. It significantly optimizes the microstructure and durability through reactive silica and the micro-aggregate effect; carbon fiber waste filaments form a conductive network to passivate the surface of steel bars, improving the corrosion resistance; its bridging effect reduces the concrete shrinkage stress and reduces microcracks. Bacillus amyloliquefaciens and silicate bacteria, as composite strains, can metabolize and secrete organic acids, dissolve solid waste minerals, release active components, and improve the activity of cementitious materials. KH-550-modified nano-SiO2 generates silanols through silane hydrolysis, enhances the bonding with cement hydration products, fills pores, and improves the compactness. The air-entraining agent introduces tiny closed air bubbles, alleviates the concentration of harmful pores, and improves the frost resistance and impermeability.

[0064] Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. If these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims

1. A low-carbon ready-mixed concrete based on the co-activation of industrial solid waste, characterized in that, It includes the following components: nano-silicon-based anti-corrosion early strength agent, cementitious material, recycled aggregate, electric furnace tailings, carbon fiber waste silk, polycarboxylate water reducer and water.

2. The low-carbon premixed concrete based on the collaborative activation of industrial solid waste according to claim 1, wherein By weight, it includes the following components: 0.8 - 1.2 parts of nano-silicon-based anti-corrosion early strength agent, 95 - 110 parts of cementitious material, 780 - 850 parts of recycled aggregate, 185 - 210 parts of electric furnace tailings, 0.1 - 0.3 parts of carbon fiber waste silk, 1.43 - 1.65 parts of polycarboxylate water reducer and 30 - 36 parts of water.

3. The low-carbon premixed concrete based on the co-activation of industrial solid waste according to claim 1, wherein The nano-silicon-based anti-corrosion early strength agent, by weight, includes the following components: 30 parts of deionized water, 8 parts of calcium nitrate, 12 parts of MCI-2020, 0.5 part of PEG-6000, 1 part of sodium gluconate, 4 parts of modified nano-silica powder, 0.5 part of sulphoaluminate cement clinker and 1.2 parts of air-entraining agent.

4. The low-carbon ready-mixed concrete based on the collaborative activation of industrial solid waste according to claim 3, characterized in that, The modified nano-silica powder, by weight, includes the following components: 5 parts of KH-550, 30 parts of deionized water and 35 parts of nano-silica.

5. The low-carbon ready-mixed concrete based on the collaborative activation of industrial solid waste according to claim 3, wherein The preparation method of the modified nano-silica powder includes: mixing 5 parts of KH-550 with 30 parts of deionized water, adjusting the pH to 5.0 with acetic acid, heating to 50°C, stirring at 500 rpm for 1 hour to fully hydrolyze the silane to form silanol, adding 35 parts of nano-silica, heating to 70°C, shearing at 8000 rpm for 8000 rpm and holding for reaction for 4 hours, and spray drying to obtain the modified nano-silica powder.

6. The low-carbon ready-mixed concrete based on collaborative activation of industrial solid waste according to claim 3, wherein, The preparation method of the nano-silicon-based anti-corrosion early strength agent includes: adding 8 parts of calcium nitrate, 12 parts of MCI-2020, 0.5 part of PEG-6000 and 1 part of sodium gluconate to 30 parts of deionized water, stirring at 400 rpm for 2 hours, adding 4 parts of modified nano-silica powder, 0.5 part of sulphoaluminate cement clinker and 1.2 parts of air-entraining agent, stirring at 150 rpm for 1 hour, passing through a high-pressure homogenizer at a pressure of 60 MPa and circulating 3 times to refine the particles, and passing through a 200-mesh sieve to obtain the nano-silicon-based anti-corrosion early strength agent.

7. The low-carbon ready-mixed concrete based on the collaborative activation of industrial solid waste according to claim 1, wherein The preparation method of low-carbon ready-mixed concrete based on the synergistic activation of industrial solid waste includes: S1. Prepare the nano-silicon-based anti-corrosion early strength agent; S2. Prepare the cementitious material; S3. Mix and form the nano-silicon-based anti-corrosion early strength agent prepared in step S1, the cementitious material prepared in step S2, recycled aggregate, electric furnace tailings, carbon fiber waste silk, polycarboxylate water reducer and water; S4. Carry out carbonation curing on the formed concrete.

8. The low-carbon ready-mixed concrete based on the collaborative activation of industrial solid waste according to claim 1, wherein, The preparation method of the cementitious material includes: mixing fly ash, steel slag, slag and portland cement, calcining at low temperature and grinding, spraying a composite alkali activator, adding Feitong granular silicon and aging to obtain the cementitious material; in the preparation of the cementitious material, the addition amounts of fly ash, steel slag, slag and portland cement are 25 parts, 15 parts, 10 parts and 20 parts respectively; the low-temperature calcination temperature is 550 °C, and it is ground to a specific surface area of 550 m 2 / kg; the composite alkali activator is composed of 40% sodium silicate, 30% sodium sulfate and 30% citric acid.

9. The low-carbon ready-mixed concrete based on the co-activation of industrial solid waste according to claim 7, wherein, In the mixing and forming steps, by weight, the addition amounts of the cementitious material, recycled aggregate, electric furnace tailings, carbon fiber waste silk, nano-silicon-based anti-corrosion early strength agent, polycarboxylate water reducer and water are 100 parts, 800 parts, 200 parts, 0.2 part, 1 part, 1.5 parts and 30 parts respectively; wet mix until the slump is 175 - 183 mm, and use high-pressure extrusion to pre-inject and form at 15 MPa with 10% concentration CO2.

10. The low-carbon ready-mixed concrete based on the collaborative activation of industrial solid waste according to claim 7, wherein, In the carbonation curing step, pass 20% concentration CO2 at 0.1 MPa for curing for 6 hours, the carbonation depth is 8 mm, and carry out standard curing for 25 - 30 days.

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