Ecological porous carbon capture and carbon sequestration-based carbon sequestration concrete and preparation method thereof

Abstract

The application discloses an ecological porous carbon sequestration concrete based on carbon capture and carbon sequestration and a preparation method thereof. The porous carbon sequestration concrete comprises 40-70 parts of Portland cement, 0-10 parts of silica fume, 0-10 parts of fly ash, 10-60 parts of calcium hydroxide, 1-5 parts of polyvinyl alcohol, 0.1-0.5 parts of polyacrylamide, 0.5-2 parts of nano-enhanced foaming agent and 20-50 parts of water. The preparation method comprises the following steps: preparing the nano-enhanced foaming agent, obtaining nano-stable foam, preparing a foam carbon sequestration cementitious material slurry, pouring into a mold, carbonizing and curing after demolding and standard curing. The porous carbon sequestration concrete has good mechanical properties and carbon sequestration performance, and can be used in the fields of building, water conservancy and traffic, and helps to reduce the implicit carbon emission of buildings and infrastructures.

Description

TECHNICAL FIELD

[0001] The present application relates to an ecological porous carbon sequestration concrete, in particular to an ecological porous carbon sequestration concrete based on carbon capture and carbon storage, and also relates to a preparation method of the above-mentioned carbon sequestration concrete. BACKGROUND

[0002] The problems of global warming and climate deterioration caused by industrial development and human activities are becoming more and more serious, the concentration of carbon dioxide in the atmosphere is rising year by year, and the ecological environment is facing great challenges. In order to solve the problem of rising carbon dioxide concentration in the atmosphere, carbon capture, storage and utilization (CCUS) technology has attracted high attention. At the same time, the building material field is also under high pressure of carbon emission reduction, and carbon sequestration concrete has received high attention and rapid development. The most common application of carbon capture and carbon storage in building materials is to accelerate the carbonation reaction of CO2 and concrete specimens through early carbonation curing, to generate stable carbonate to fill the initial pores, so that the concrete structure is dense, the mechanical properties are improved, and the durability is also improved.

[0003] Ordinary concrete has low porosity, and the diffusion of CO2 from outside to inside is limited by the matrix during carbonation, resulting in low carbon sequestration efficiency. Foam concrete is a lightweight, heat-insulating, heat-insulating and fire-resistant concrete material, which has high porosity and is beneficial to the diffusion of CO2 gas. However, due to the low content of carbon sequestration components in traditional foam porous concrete, the overall carbon sequestration amount is low. In addition, the foam stability of foam porous concrete is poor, which is prone to shrinkage and deformation, resulting in uneven distribution of air holes in the foam concrete, and stress concentration when a load is applied, which can accelerate the destruction of foam concrete. Currently, calcium hydroxide produced by low-energy production is increasingly valued as a carbon sequestration component of carbon sequestration concrete, but as a raw material introduced into concrete, it can cause a decrease in concrete strength, which is more obvious in porous concrete, limiting its application in porous concrete systems. Carbon sequestration concrete faces the problems of low carbon sequestration efficiency and reduced mechanical properties after the introduction of carbon sequestration components. SUMMARY

[0004] The present application aims to provide an ecological porous carbon sequestration concrete based on carbon capture and carbon storage with carbon capture and carbon storage functions, and strong mechanical properties and high carbon sequestration amount, and also provides a preparation method of the above-mentioned carbon sequestration concrete.

[0005] Technical solution: The ecological porous carbon sequestration concrete based on carbon capture and carbon storage of the present application comprises cement 40-70 parts, silica fume 0-10 parts, fly ash 0-10 parts, calcium hydroxide 10-60 parts, polyvinyl alcohol 1-5 parts, polyacrylamide 0.1-0.5 parts, nano-modified foaming agent 0.5-2 parts, and water 20-50 parts.

[0006] The nano-modified foaming agent comprises 4-6 parts of nano-silicon dioxide, 1-3 parts of nano-titanium dioxide, 5-8 parts of a surfactant, 5-8 parts of a dispersant, 1-2 parts of a stabilizer, and 80-90 parts of water.

[0007] The preparation method of the carbon sequestration concrete comprises the following steps:

[0008] (1) The nano-silicon dioxide and the nano-titanium dioxide are added into water for stirring and ultrasonic dispersion treatment, and then the dispersant is added for continuous stirring. After the agglomerates in the suspension are completely dispersed, the surfactant and the stabilizer are added for continuous stirring to prepare the nano-modified foaming agent;

[0009] (2) The nano-modified foaming agent is taken out, diluted, and compressed and foamed to obtain a nano-stable foam;

[0010] (3) The cement, silica fume, fly ash, calcium hydroxide, polyvinyl alcohol, polyacrylamide, and water are added into a stirrer for mixing and stirring to obtain a cementitious material slurry;

[0011] (4) The nano-stable foam is added into the cementitious material slurry for stirring to obtain a foam carbon sequestration cementitious material slurry, which is poured, solidified, demolded, carbonized and cured, and then standard cured to obtain an ecological porous carbon sequestration concrete based on carbon capture and carbon sequestration.

[0012] In step (1), the ultrasonic dispersion time is 20-30 minutes, the stirring time is 20-40 minutes, and the stirring temperature is 50-55℃.

[0013] In step (1), the nano-silicon dioxide is hydrophobic, the surfactant is cocamidopropyl betaine or lauramidopropyl betaine, the stabilizer is hydroxypropyl methyl cellulose, and the dispersant is polyethylene glycol 2000.

[0014] In step (2), the nano-modified foaming agent is diluted by 15-20 times with water.

[0015] In step (2), the air compressor foaming pressure is 0.35-0.45 Mpa.

[0016] In step (3), the cement is P.II 42.5R grade Portland cement, the fly ash is I-grade fly ash or II-grade fly ash, the calcium hydroxide has a fineness of 100-300 meshes, the polyvinyl alcohol has a polymerization degree of 1700, and the polyacrylamide has a molecular weight of 20-25 million.

[0017] In step (4), the carbonization and curing are performed at a temperature of 15-25℃, a humidity of 95%-99%, and a carbon dioxide concentration of 50%-80% for 12-24 hours.

[0018] In step (4), the standard curing is performed for 15-30 days at 15-25 DEG C and 50-99% humidity.

[0019] Invention principle: The porous carbon sequestration concrete of the present application has good mechanical properties and carbon sequestration performance. The nano-stable foam prepared by nano-modified foaming agent realizes the porosity of the concrete. The porous structure formed by the super-stable foam is uniformly distributed, which is conducive to the diffusion of CO2 and rapid reaction with the carbon sequestration component, thereby improving the carbon sequestration efficiency. At the same time, based on the high-performance additive technology, the strength of the composite polymer film and the carbon dioxide adsorption site are improved by the synergistic effect of polyvinyl alcohol and polyacrylamide. The porous carbon sequestration concrete can maintain good mechanical properties while improving the carbon sequestration performance. It is applied to the fields of building, water conservancy and transportation, and helps to reduce the implicit carbon emissions of buildings and infrastructure.

[0020] Advantages: Compared with the prior art, the present application has the following advantages: (1) The super-stable foam realizes the porosity of the concrete. The porous structure formed by the super-stable foam is uniformly distributed, which is conducive to the diffusion of CO2 and rapid reaction with the carbon sequestration component, thereby improving the carbon sequestration efficiency. The carbon sequestration amount is obviously improved within 12 hours. (2) Based on the high-performance additive technology, the strength of the composite polymer film and the carbon dioxide adsorption site are improved by the synergistic effect of polyvinyl alcohol and polyacrylamide. The porous carbon sequestration concrete can maintain good mechanical properties while improving the carbon sequestration performance. DETAILED DESCRIPTION

[0021] The raw materials of the present application are commercially available. The technical solutions of the present application are further described below in conjunction with specific examples.

[0022] Example 1

[0023] An ecological porous carbon sequestration concrete based on carbon capture and carbon sequestration includes the following mass components: 50 parts of Portland cement, 5 parts of silica fume, 5 parts of fly ash, 40 parts of calcium hydroxide, 2 parts of polyvinyl alcohol, 0.2 parts of polyacrylamide, 0.6 parts of nano-modified foaming agent, and 50 parts of water.

[0024] The nano-modified foaming agent includes the following mass components: 4 parts of nano-silicon dioxide, 2 parts of nano-titanium dioxide, 6 parts of surfactant, 6 parts of dispersant, 1 part of stabilizer, and 85 parts of water.

[0025] The preparation method of the above-mentioned ecological porous carbon sequestration concrete is as follows:

[0026] (1)Nano-silicon dioxide and nano-titanium dioxide are added into water for stirring and ultrasonic dispersion treatment, the ultrasonic dispersion time is 20 minutes, the stirring time is 25 minutes, the stirring temperature is 50 DEG C, then a dispersant is added for continuous stirring, after the complete dispersion of the agglomerates in the suspension, a surfactant and a stabilizer are added for continuous stirring, thus a nano-modified foaming agent is prepared, the nano-silicon dioxide is hydrophobic, the surfactant is cocamidopropyl betaine, the stabilizer is hydroxypropyl methyl cellulose, and the dispersant is polyethylene glycol 2000;

[0027] (2)The nano-modified foaming agent is diluted 15 times with water, and compressed foaming is carried out by using an air compressor, the foaming pressure of the air compressor is 0.35 Mpa, thus a nano-stable foam is obtained;

[0028] (3)Cement, silica fume, fly ash, calcium hydroxide, polyvinyl alcohol, polyacrylamide and water are added into a stirrer for mixing and stirring, thus a cementitious material slurry is obtained, the cement is P.II 42.5R grade Portland cement, the fly ash is I grade fly ash or II grade fly ash, the fineness of the calcium hydroxide is 200 meshes, the polyvinyl alcohol has a polymerization degree of 1700, and the polyacrylamide has a molecular weight of 20 million;

[0029] (4)The nano-stable foam is added into the cementitious material slurry for stirring, thus a foam carbon sequestration cementitious material slurry is obtained, which is poured into a mold for solidification, and cured at room temperature for 1 day; after demolding, carbonization curing is carried out at a temperature of 20 DEG C, a humidity of 95% and a carbon dioxide concentration of 60%; then standard curing is carried out at a temperature of 15 DEG C, a humidity of 50% and for a time period of 26 days, thus an ecological porous carbon sequestration concrete based on carbon capture and carbon storage is obtained.

[0030] Example 2

[0031] An ecological porous carbon sequestration concrete based on carbon capture and carbon storage comprises the following components in mass: Portland cement 60 parts; silica fume 8 parts; fly ash 6 parts; calcium hydroxide 55 parts; polyvinyl alcohol 3 parts; polyacrylamide 0.3 parts; nano-enhanced foaming agent 1 part; and water 45 parts.

[0032] The nano-modified foaming agent comprises the following components in mass: nano-silicon dioxide 4 parts, nano-titanium dioxide 2 parts, surfactant 6 parts, dispersant 6 parts, stabilizer 1 part, and water 85 parts.

[0033] The preparation method of the ecological porous carbon sequestration concrete is as follows:

[0034] (1) Nanometer silica and nanometer titanium dioxide are added into water for stirring and ultrasonic dispersion treatment, the ultrasonic dispersion time is 25 minutes, the stirring time is 20 minutes, the stirring temperature is 55℃, then a dispersant is added for continuous stirring, after the complete dispersion of the agglomerates in the suspension, a surfactant and a stabilizer are added for continuous stirring, to obtain a nanometer modified foaming agent, the nanometer silica is hydrophobic, the surfactant is lauryl amidopropyl betaine, the stabilizer is hydroxypropyl methyl cellulose, and the dispersant is polyethylene glycol 2000;

[0035] (2) The nanometer modified foaming agent is diluted 20 times with water, and compressed foaming is performed by using an air compressor, the foaming pressure of the air compressor is 0.45Mpa, to obtain a nanometer stable foam;

[0036] (3) Cement, silica fume, fly ash, calcium hydroxide, polyvinyl alcohol, polyacrylamide and water are added into a stirrer for mixing and stirring, to obtain a cementitious material slurry, the cement is P.II 42.5R grade Portland cement, the fly ash is II grade fly ash, the calcium hydroxide has a fineness of 300 meshes, the polyvinyl alcohol has a polymerization degree of 1700, and the polyacrylamide has a molecular weight of 25 million;

[0037] (4) The nanometer stable foam is added into the cementitious material slurry for stirring to obtain a foam carbon sequestration cementitious material slurry, which is poured into a mold for solidification, and cured at room temperature for 1 day; after demolding, carbonization curing is performed at a temperature of 25℃, a humidity of 99% and a carbon dioxide concentration of 80%; then standard curing is performed at a temperature of 20℃ and a humidity of 90% for 20 days, to obtain an ecological porous carbon sequestration concrete based on carbon capture and carbon storage.

[0038] Comparative Example 1

[0039] A carbon sequestration concrete, compared with Example 1, removes the polyacrylamide, and comprises the following mass components: Portland cement 50 parts; silica fume 5 parts; fly ash 5 parts; calcium hydroxide 40 parts; polyvinyl alcohol 2 parts; nanometer modified foaming agent 0.6 parts, and water 50 parts.

[0040] The nanometer modified foaming agent comprises the following mass components: nanometer silica 4 parts, nanometer titanium dioxide 2 parts, surfactant 6 parts, dispersant 6 parts, stabilizer 1 part, and water 85 parts.

[0041] The preparation method of the above carbon sequestration concrete is as follows:

[0042] (1) The nano-silicon dioxide and nano-titanium dioxide are added into water for stirring and ultrasonic dispersion treatment, the ultrasonic dispersion time is 20 minutes, the stirring time is 25 minutes, the stirring temperature is 50 DEG C, then the dispersant is added for continuous stirring, after the agglomerates in the suspension are completely dispersed, the surfactant and the stabilizer are added for continuous stirring, thus the nano-modified foaming agent is prepared, the nano-silicon dioxide is hydrophobic, the surfactant is cocamidopropyl betaine, the stabilizer is hydroxypropyl methyl cellulose, and the dispersant is polyethylene glycol 2000;

[0043] (2) The nano-modified foaming agent is diluted 15 times with water, and is compressed and foamed by using an air compressor, the foaming pressure of the air compressor is 0.35 Mpa, thus the nano-stable foam is obtained;

[0044] (3) The cement, silica fume, fly ash, calcium hydroxide, polyvinyl alcohol and water are added into a stirrer for mixing and stirring, thus the cementitious material slurry is obtained, the cement is P.II 42.5R grade Portland cement, the fly ash is I grade fly ash or II grade fly ash, the fineness of the calcium hydroxide is 200 meshes, and the polymerization degree of the polyvinyl alcohol is 1700;

[0045] (4) The nano-stable foam is added into the cementitious material slurry for stirring, thus the foam carbon sequestration cementitious material slurry is obtained, the foam carbon sequestration cementitious material slurry is poured into a mold for solidification, and is cured at normal temperature for 1 day; after demolding, carbonization curing is carried out, the carbonization curing temperature is 20 DEG C, the humidity is 95%, and the carbon dioxide concentration is 60%; then standard curing is carried out, the temperature is 15 DEG C, the humidity is 50%, and the curing time is 26 days, thus the carbon sequestration concrete is obtained.

[0046] Comparative Example 2

[0047] A carbon sequestration concrete, compared with Example 1, removes the polyvinyl alcohol, and comprises the following mass components: Portland cement 50 parts; silica fume 5 parts; fly ash 5 parts; calcium hydroxide 40 parts; polyacrylamide 0.2 parts; nano-modified foaming agent 0.6 parts; and water 50 parts.

[0048] The nano-modified foaming agent comprises the following mass components: nano-silicon dioxide 4 parts, nano-titanium dioxide 2 parts, surfactant 6 parts, dispersant 6 parts, stabilizer 1 part, and water 85 parts.

[0049] The preparation method of the above carbon sequestration concrete is as follows:

[0050] (1) The nano-silicon dioxide and nano-titanium dioxide are added into water for stirring and ultrasonic dispersion treatment, the ultrasonic dispersion time is 20 minutes, the stirring time is 25 minutes, the stirring temperature is 50 DEG C, then the dispersant is added for continuous stirring, after the agglomerates in the suspension are completely dispersed, the surfactant and the stabilizer are added for continuous stirring, thus the nano-modified foaming agent is prepared, the nano-silicon dioxide is hydrophobic, the surfactant is cocamidopropyl betaine, the stabilizer is hydroxypropyl methyl cellulose, and the dispersant is polyethylene glycol 2000;

[0051] (2) The nano-modified foaming agent is diluted 15 times with water, and is foamed by using an air compressor, and the foaming pressure of the air compressor is 0.35 MPa, to obtain nano-stable foam;

[0052] (3) Cement, silica fume, fly ash, calcium hydroxide, polyacrylamide and water are added into a stirrer to be mixed and stirred to obtain a cementitious material slurry, wherein the cement is P.II 42.5R grade Portland cement; the fly ash is I grade fly ash or II grade fly ash; the calcium hydroxide has a fineness of 200 meshes; and the polyacrylamide has a molecular weight of 20 million;

[0053] (4) The nano-stable foam is added into the cementitious material slurry to be stirred to obtain a foam carbon sequestration cementitious material slurry, which is poured into a mold to be cured, and is cured at room temperature for 1 day; after demolding, carbonization curing is performed at a temperature of 20℃, a humidity of 95% and a carbon dioxide concentration of 60%; and then standard curing is performed at a temperature of 15℃, a humidity of 50% and for a curing time of 26 days, to obtain carbon sequestration concrete.

[0054] According to the test of JC / T2357-2016, the compressive strength, the flexural strength and the carbon sequestration performance of the examples and the comparative examples are tested, and the results show that the ecological porous carbon sequestration concrete prepared in Example 1 has a compressive strength of 7.2 MPa, a flexural strength of 2.1 MPa and a 12h carbon sequestration rate of 17%; the ecological porous carbon sequestration concrete prepared in Example 2 has a compressive strength of 8.3 MPa, a flexural strength of 2.4 MPa and a 12h carbon sequestration rate of 20%; the carbon sequestration concrete prepared in Comparative Example 1 has a compressive strength of 3.5 MPa, a flexural strength of 1.1 MPa and a 12h carbon sequestration rate of 9%; and the carbon sequestration concrete prepared in Comparative Example 2 has a compressive strength of 2.7 MPa, a flexural strength of 0.8 MPa and a 12h carbon sequestration rate of 11%.

Claims

1. An ecological porous carbon sequestration concrete based on carbon capture and carbon sequestration, characterized in that, The carbon sequestration concrete comprises cement 40-70 parts, silica fume 0-10 parts, fly ash 0-10 parts, calcium hydroxide 10-60 parts, polyvinyl alcohol 1-5 parts, polyacrylamide 0.1-0.5 parts, nano-modified foaming agent 0.5-2 parts, and water 20-50 parts; the nano-modified foaming agent comprises nano-silicon dioxide 4-6 parts, nano-titanium dioxide 1-3 parts, surfactant 5-8 parts, dispersant 5-8 parts, stabilizer 1-2 parts, and water 80-90 parts.

2. A method of producing the carbon sequestering concrete of claim 1, wherein, The method comprises the following steps: (1) nano-silicon dioxide and nano-titanium dioxide are added into water for stirring and ultrasonic dispersion treatment, then a dispersant is added for continuous stirring, after the agglomerates in the suspension are completely dispersed, a surfactant and a stabilizer are added for continuous stirring to prepare a nano-modified foaming agent; (2) the nano-modified foaming agent is taken, diluted, and compressed to foam to obtain nano-stable foam; (3) cement, silica fume, fly ash, calcium hydroxide, polyvinyl alcohol, polyacrylamide, and water are added into a stirrer for mixing and stirring to obtain a cementitious material slurry; (4) the nano-stable foam is added into the cementitious material slurry for stirring to obtain a foam carbon sequestration cementitious material slurry, which is poured, solidified, demolded, carbonized, and cured to obtain ecological porous carbon sequestration concrete based on carbon capture and carbon sequestration.

3. The production method according to claim 2, characterized by, In step (1), the ultrasonic dispersion time is 20-30 minutes, the stirring time is 20-40 minutes, and the stirring temperature is 50-55 DEG C.

4. The preparation method according to claim 2, characterized in that, In step (1), the nano-silicon dioxide is hydrophobic, the surfactant is cocamidopropyl betaine or lauramidopropyl betaine, the stabilizer is hydroxypropyl methyl cellulose, and the dispersant is polyethylene glycol 2000.

5. The preparation method according to claim 2, characterized in that, In step (2), the nano-modified foaming agent is diluted by 15-20 times with water.

6. The preparation method according to claim 2, characterized in that, In step (2), the foaming pressure of the air compressor is 0.35-0.45 MPa.

7. The preparation method according to claim 2, characterized in that, In step (3), the cement is P.II 42.5R grade Portland cement, the fly ash is I or II grade fly ash, the calcium hydroxide has a fineness of 100-300 meshes, the polyvinyl alcohol has a polymerization degree of 1700, and the polyacrylamide has a molecular weight of 20-25 million.

8. The preparation method according to claim 2, characterized in that, In step (4), the carbonization curing is performed at a temperature of 15-25 DEG C, a humidity of 95-99%, and a carbon dioxide concentration of 50-80% for 12-24 hours.

9. The preparation method according to claim 2, characterized in that, In step (4), the standard curing is performed at a temperature of 15-25 DEG C and a humidity of 50-99% for 15-30 days.