Construction method and carbon dioxide emission reduction method

Abstract

To provide a construction method capable of reducing carbon dioxide emissions, and a carbon dioxide emission reduction method.SOLUTION: A construction method comprises mixing soil constituting ground, a carbon dioxide immobilizing material capable of immobilizing carbon dioxide, and one or more ground solidifying materials selected from cement and cement-based solidifying materials, so as to solidify the ground. The carbon dioxide immobilizing material is preferably biochar.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a construction method and a method for reducing carbon dioxide emissions. [Background technology]

[0002] BACKGROUND ART As a ground improvement method (construction method) for solidifying the soil that constitutes the ground, a method using cement or a cement-based solidification material (hereinafter also referred to as "ground solidification material") is known. For example, a construction method for ground improvement (construction method) has been proposed in Patent Document 1. Patent Document 1 describes a construction method in which a ground solidification material is added to a primary mixture of soil and molten slag that constitutes the ground, and the mixture is mixed to solidify the ground. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent application No. 2022-181842 Summary of the Invention [Problem to be solved by the invention]

[0004] Currently, reducing carbon dioxide emissions is a global goal, and therefore soil solidification methods are also required to reduce carbon dioxide emissions. The present invention has been made in consideration of the above circumstances, and aims to provide a construction method and a method for reducing carbon dioxide emissions that can reduce carbon dioxide emissions. [Means for solving the problem]

[0005] In order to solve the above problems, the present invention has the following aspects. [1] The soil that makes up the ground, a carbon dioxide immobilization material capable of immobilizing carbon dioxide; A construction method in which the ground is solidified by mixing it with one or more ground solidification materials selected from cement and cement-based solidification materials.

[0006] [2] The construction method according to [1], wherein the carbon dioxide immobilization material is biochar. [3] 1m 3 The construction method according to [2], wherein the amount of the carbon dioxide immobilization material used relative to the soil is 5 kg to 150 kg. [4] The construction method according to [2], wherein the amount of the carbon dioxide immobilized material used per 100 kg of the ground solidification material is 18 kg to 100 kg. [5] The construction method according to [1], wherein the carbon dioxide immobilization material and the ground solidification material are mixed to form a mixture, and the mixture is mixed with the soil.

[0007] [6] The soil that makes up the ground; a carbon dioxide immobilization material capable of immobilizing carbon dioxide; A method for reducing carbon dioxide emissions in a construction method in which one or more ground solidification materials selected from cement and cement-based solidification materials are mixed to solidify the ground, The carbon dioxide emissions resulting from construction can be offset by the carbon dioxide emissions fixed by the carbon dioxide immobilization material. [Effects of the Invention]

[0008] According to the construction method and the method for reducing carbon dioxide emissions of the present invention, it is possible to reduce the amount of carbon dioxide emissions caused by construction. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a graph showing the relationship between the amount of cement-based solidification material added and the unconfined compressive strength of the test specimens of Examples 1 to 3 and Comparative Examples 1 to 3. [Figure 2] FIG. 2 is a graph showing the relationship between the amount of cement-based solidification material added and the unconfined compressive strength of the test specimens of Examples 4 to 7 and Comparative Examples 4 to 7. DETAILED DESCRIPTION OF THE INVENTION

[0010] ≪Construction method≫ The construction method of the present invention is a method of solidifying the ground by mixing soil constituting the ground, a carbon dioxide immobilizing material capable of immobilizing carbon dioxide, and a ground solidification material. In the construction method of the present invention, the ground is solidified by mixing soil, a carbon dioxide immobilization material, and a ground solidification material, so the amount of carbon dioxide immobilized (stored) in the ground by the carbon dioxide immobilization material can offset the amount of carbon dioxide emitted attributable to construction. As a result, the amount of carbon dioxide emitted attributable to construction can be reduced. The construction method of the present invention is preferably a method of solidifying the ground by mixing only soil, a carbon dioxide immobilization material, and a ground solidification material.

[0011] <Sat> In this specification, "soil" refers to soil, and includes clayey soil, sandy soil, and gravelly soil. Clayey soil is a general term for soil with small particle size. In this specification, "clay soil" refers to soil that contains 50% by mass or more of soil particles (fine particles) with a particle size of 75 μm or less. "Sandy soil" refers to soil that contains 50% or more by mass of particles with a particle size of more than 75 μm (coarse particles) and has a particle size of 2.0 mm or less. "Gravitational soil" refers to soil with a particle size of more than 2.0 mm. Gravelly soil generally has a particle size of 75 mm or less. Clayey soil has a relatively low ground strength, and it is often necessary to increase the ground strength. For this reason, clayey soil is preferred as the soil.

[0012] <Carbon dioxide fixed product> The carbon dioxide immobilization material is capable of immobilizing carbon dioxide. The carbon dioxide immobilization material is not particularly limited as long as it is a material that can immobilize carbon dioxide, and examples thereof include biochar and calcium carbonate, with biochar being preferred. By using biochar as the carbon dioxide immobilization material, carbon dioxide emissions resulting from construction can be effectively offset.

[0013] As used herein, biochar refers to a solid material produced by heating biomass at temperatures above 350°C under controlled oxygen concentrations that do not cause combustion. Examples of biochar include white charcoal, black charcoal, powdered charcoal, and sawdust charcoal.

[0014] <Ground solidification material> Ground solidification materials are mixed into the soil that makes up the ground to solidify the soil and improve the strength of the ground. As the ground solidification material, one or more materials selected from cement and cement-based solidification materials are used.

[0015] Examples of cement include portland cement, blended cement, ecocement, and special cement. Examples of Portland cement include various types of Portland cement such as normal, early strength, extra early strength, medium heat, low heat, and sulfate resistant.

[0016] Ordinary Portland cement is the most commonly used cement for construction and manufacturing purposes. High-early-strength Portland cement is a cement that provides high strength early on and continues to increase in strength over the long term. Ultra-high-early-strength Portland cement is a cement that contains even more alite (C3S) and has a finer particle size than high-early-strength Portland cement. Ultra-high-early-strength Portland cement develops the three-day strength of high-early-strength Portland cement in just one day. Moderate-heat Portland cement has less C3S and aluminate (C3A) and more belite (C2S) to reduce the heat of hydration, resulting in a cement with low initial strength but high long-term strength. Low-heat Portland cement has an even higher C2S content than moderate-heat Portland cement, with a C2S content of 40% by mass or more, in order to reduce the heat of hydration.Low-heat Portland cement has the characteristics of good strength development in the high-strength range and easily achieving high fluidity in concrete with a low water-powder ratio. Sulfate-resistant Portland cement is cement that has a low C3A content, making it less reactive with sulfates. Sulfate-resistant Portland cement is suitable for construction in soil areas that contain sulfates, and also has excellent resistance to seawater.

[0017] Examples of blended cement include blast furnace cement, silica cement, and fly ash cement. Blast furnace cement is cement mixed with blast furnace slag. Blast furnace slag is made by combining non-iron components such as silica contained in iron ore and ash from coke with limestone, an auxiliary material. Blast furnace slag has latent hydraulic properties and gradually hardens when stimulated by Portland cement. Blast furnace cement has low initial strength but high long-term strength. Blast furnace cement is classified into Type A, Type B, and Type C blast furnace cement depending on the amount of blast furnace slag mixed in (JIS R5211:2009). Blast-furnace cement type A: Blast-furnace slag content 5-30% by mass Blast-furnace cement type B: Blast-furnace slag content 10-60% by mass Blast furnace cement type C: blast furnace slag content 60-70% by mass

[0018] Silica cement is a cement mixed with powder of high-purity silica, etc. Silica cement is used for products that require autoclave curing. Fly ash cement is cement mixed with fly ash, which is produced when pulverized coal is burned. Fly ash cement has great long-term strength and can be used to create durable structures.

[0019] Ecocement is made from waste materials such as municipal waste incineration ash and sewage sludge, with a dry weight of 500 kg or more per ton of product. Ecocement is classified into regular ecocement and rapid hardening ecocement depending on the amount of chloride ions in the cement. Ordinary ecocement is dechlorinated during the manufacturing process and has a chloride ion content of 0.1% or less. Ordinary ecocement has similar properties to ordinary Portland cement in terms of setting time and mortar compressive strength. Rapid-hardening ecocement is an ecocement with a chloride ion content of 0.5% to 1.5%. Rapid-hardening ecocement is a cement that has rapid hardening properties and takes advantage of its ability to develop strength early.

[0020] Special cements are manufactured as non-JIS standard products, and include white Portland cement, alumina cement, ultra-fast hardening cement, colloidal cement, oil well cement, low heat cement, and high belite cement. High belite cement is a low-heat cement that has been adjusted to minimize the amount of aluminate (C3A) phase, which generates a large amount of heat, and to have belite (C2S), which has a low heat of hydration, as the main component. Because high belite cement can suppress the heat of hydration, it is easy to create concrete with good fluidity. High belite cement is suitable for use in large structures.

[0021] Portland cement generates carbon dioxide from the thermal decomposition of limestone during firing (CaCO3 → CaO + CO2↑) and from the fuel required for firing. On the other hand, ground granulated blast furnace slag, which is an admixture for blast furnace cement, does not require firing, so the amount of carbon dioxide emitted during cement production can be reduced in proportion to the amount mixed. For this reason, the cement of this embodiment is preferably blast furnace cement, and more preferably blast furnace cement type B or blast furnace cement type C, which contain a large amount of blast furnace slag. The cement may be used alone or in combination of two or more kinds. Furthermore, instead of using a blended cement, for example, blast furnace cement, a cement other than blast furnace cement may be mixed with blast furnace slag during construction.

[0022] Cement-based solidification materials are solidification materials that use cement as a base and add various active ingredients in order to effectively improve the ground. The active ingredient may be, for example, an inorganic compound containing a sulfate. The cement-based solidification material may be a commercially available product, and examples of commercially available cement-based solidification materials include the Geoset (registered trademark) series from Taiheiyo Cement Corporation.

[0023] As a ground solidification material, a cement-based solidification material is preferred because it can further increase the strength of the ground, and a cement-based solidification material based on blast furnace cement is more preferred because it can further reduce CO2 emissions, and a cement-based solidification material based on blast furnace cement type B or blast furnace cement type C is even more preferred, and a cement-based solidification material based on blast furnace cement type C is particularly preferred.

[0024] In the construction method of the present embodiment, it is preferable to mix the carbon dioxide immobilization material and the ground solidification material to form a mixture, and then mix the mixture with soil. The reason for this is as follows. Typically, the amounts of carbon dioxide immobilization material and ground solidification material used are very small compared to the mass of the soil with which they are mixed. Furthermore, when mixing the soil that makes up the ground with materials to be mixed with the soil, such as ground solidification material, a large mixing machine must be used. For these reasons, mixing a carbon dioxide immobilization material and a ground solidification material is easier than mixing soil with a carbon dioxide immobilization material or mixing soil with a ground solidification material, and because less energy is required for mixing and stirring, carbon dioxide emissions are also smaller.

[0025] In the above construction method, a carbon dioxide immobilization material and a ground solidification material are mixed to form a mixture, and then the mixture is mixed with soil. This allows the soil and the materials to be mixed with the soil to be mixed only once. Therefore, compared to a case where, for example, a first mixing step of mixing soil with a carbon dioxide immobilization material and a second mixing step of adding a ground solidification material to the mixture of soil and carbon dioxide immobilization material are performed, the number of times the soil and the materials to be mixed with the soil can be reduced, thereby further reducing carbon dioxide emissions. Furthermore, by premixing the carbon dioxide immobilization material and the ground solidification material to form a mixture, the amounts (mass) of the carbon dioxide immobilization material and the ground solidification material used relative to the volume of soil can be easily and accurately adjusted, compared to a case where the carbon dioxide immobilization material and the ground solidification material are separately measured and added, thereby improving the quality of construction.

[0026] The method for mixing the carbon dioxide immobilization material and the ground solidification material to prepare a mixture can be any known method, and is not particularly limited. For example, the carbon dioxide immobilization material and the ground solidification material may be mixed in a predetermined ratio using a known mixer / stirrer. As a method for mixing the soil and the mixture, for example, the soil that forms the ground may be excavated in situ, and then the mixture may be added to the excavated soil and mixed and stirred, or the mixture may be spread on the surface of the soil, and then the soil and the mixture may be mixed and stirred while the soil that forms the ground is being excavated. Examples of mixing machines that mix soil and the mixture include backhoes, self-propelled soil improvement machines, wheeled stabilizers, crawler stabilizers, mud vehicles, and soil improvers.

[0027] The amount of carbon dioxide immobilization material to be mixed with the ground solidification material can be determined appropriately depending on the types of soil, ground solidification material, and carbon dioxide immobilization material. For example, when the carbon dioxide immobilization material is biochar, the amount of biochar used per 100 kg of ground solidification material is preferably 18 kg or more, more preferably 20 kg or more, and even more preferably 25 kg or more. When the amount of biochar used per 100 kg of ground solidification material is equal to or greater than the above-mentioned lower limit, carbon dioxide emissions resulting from construction can be further reduced. There are no particular limitations on the upper limit of the amount of carbon dioxide immobilization material used, and it is, for example, 100 kg or less per 100 kg of ground solidification material.

[0028] Also, 1m 3 The amount of carbon dioxide immobilization material used relative to the soil can be determined appropriately depending on the type of soil, ground solidification material, and carbon dioxide immobilization material. For example, when the carbon dioxide immobilization material is biochar, 3 The amount of carbon dioxide immobilization material used per 1 m of soil is preferably 5 kg or more, more preferably 10 kg or more, and even more preferably 20 kg or more. 3 When the amount of biochar used relative to the soil is equal to or greater than the above lower limit, carbon dioxide emissions due to construction can be further reduced. 3 The amount of carbon dioxide immobilization material used relative to the soil is not particularly limited, and is, for example, 150 kg or less.

[0029] Also, 1m 3 The amount of soil solidification material to be added to the soil is determined appropriately depending on the type of soil and soil solidification material, the desired strength of the solidified ground, etc. 3 The amount of soil solidification material added to the soil is preferably 200 kg or less, more preferably 180 kg or less, and even more preferably 150 kg or less. 3 When the amount of the ground solidification material added to the soil is equal to or less than the above upper limit, the amount of carbon dioxide emitted from the manufacture of the ground solidification material can be reduced, and the amount of carbon dioxide emitted from construction can be further reduced. 3The amount of the ground solidification material added to the soil is preferably 20 kg or more, more preferably 30 kg or more, and even more preferably 50 kg or more.

[0030] In addition, in the construction method of this embodiment, when the carbon dioxide immobilization material is biochar, the amount of biochar used per 100 kg of ground solidification material is 18 kg to 100 kg, and 3 The amount of the ground solidification material added to the soil is preferably 5 kg to 150 kg, because this allows the solidified ground to have the same strength as when no carbon dioxide immobilization material is used.

[0031] In the construction method of this embodiment, soil, a carbon dioxide immobilization material, and a ground solidification material are mixed, so the amount of carbon dioxide immobilized (stored) in the ground by the carbon dioxide immobilization material can offset the carbon dioxide emissions resulting from construction. Therefore, by using the construction method of this embodiment, it is possible to reduce the amount of carbon dioxide emissions resulting from construction, thereby contributing to reducing the burden on the global environment.

[0032] <<How to reduce carbon dioxide emissions>> The method for reducing carbon dioxide emissions of the present invention is a method for reducing carbon dioxide emissions in a construction method in which soil constituting the ground, a carbon dioxide immobilization material capable of immobilizing carbon dioxide, and one or more ground solidification materials selected from cement and cement-based solidification materials are mixed to solidify the ground. The method for reducing carbon dioxide emissions of the present invention is a method in which the carbon dioxide emissions resulting from construction can be offset by the carbon dioxide emissions fixed by the carbon dioxide immobilizing material.

[0033] The soil, carbon dioxide immobilization material, and ground solidification material used in the method for reducing carbon dioxide emissions of the present invention can be the same as the soil, carbon dioxide immobilization material, and ground solidification material used in the above-mentioned construction method, and can be used in the same amounts.

[0034] In the method for reducing carbon dioxide emissions of this embodiment, the amount of carbon dioxide emissions resulting from construction is the total amount of carbon dioxide emissions that can be immobilized in the carbon dioxide immobilization material, the process of manufacturing the ground solidification material, and the above-mentioned construction method (hereinafter also referred to as the ground improvement process). The carbon dioxide immobilization material can immobilize carbon dioxide. In this embodiment, the amount of carbon dioxide that can be immobilized by the carbon dioxide immobilization material is defined as the offset amount that can offset the carbon dioxide emissions resulting from construction. This offset amount is defined as - (minus) X (kg). Biochar, which is a carbon dioxide immobilization material, can immobilize approximately 2.3 kg of carbon dioxide per 1 kg.

[0035] In the process of manufacturing ground solidification material, a large amount of carbon dioxide is emitted when cement is burned. This amount of carbon dioxide is designated as Y (kg). The mass of carbon dioxide emitted when manufacturing 1 kg of ground solidification material is 470 g. In the ground improvement process, carbon dioxide is emitted when the soil, carbon dioxide immobilization material, and ground solidification material are mixed. The amount of carbon dioxide emitted is designated as Z (kg).

[0036] In this embodiment, if the total amount of carbon dioxide emissions is S (kg), it is expressed as S=(Y+ZX). Therefore, by mixing carbon dioxide immobilization material into the soil to be solidified, reducing the amount of ground solidification material used, and further reducing emissions during the ground improvement process, the total amount of carbon dioxide emissions can be reduced.

[0037] The method for reducing carbon dioxide emissions of this embodiment uses a carbon dioxide immobilization material, and therefore can reduce the amount of carbon dioxide emissions caused by construction compared to when no carbon dioxide immobilization material is used. More specifically, the carbon dioxide emissions caused by construction can be offset by the carbon dioxide immobilization material mixed with the soil that makes up the ground and fixed in the solidified ground. Therefore, by using the method for reducing carbon dioxide emissions of this embodiment, it is possible to reduce the amount of carbon dioxide emissions caused by construction and contribute to reducing the burden on the global environment. [Example]

[0038] The present invention will be described in more detail below using examples, but the present invention is not limited to these examples. The materials used are as follows.

[0039] [Examples 1 to 3] [Materials used] <Sat> Clayey soil (uniaxial compressive strength 121kN / m 2 ) <Carbon dioxide fixed product> Biochar: Plus-1, manufactured by Nara Tanka Kogyo Co., Ltd. <Ground solidification material> Cement-based solidification material: Geoset (registered trademark) 200, manufactured by Taiheiyo Cement Corporation

[0040] The biochar and the cement-based solidification material shown in Table 1 were mixed in the amounts shown in Table 1 to produce mixtures 1 to 3. 3 Mixtures 1 to 3 were mixed with the above soil and stirred and mixed uniformly in a mixer (a Hobart-type soil mixer with a capacity of 4.7 L, rotational speed of 120 to 300 rpm, revolution speed of 30 to 125 rpm) in a room at room temperature of 20°C, to obtain improved soils of Examples 1 to 3.

[0041] [Table 1]

[0042] The improved soil obtained was placed in a mold fitted with a cylindrical collar measuring 5 cm in diameter and 10 cm in height, and compacted using a 1.5 kg rammer to produce specimens for Examples 1 to 3. The compaction method involved free-falling a 1.5 kg hammer from a height of 20 cm, compacting the soil in three layers. Each layer was compacted 12 times. The amount of improved soil added to the mold was adjusted so that the amount of improved soil compacted per layer would be about one-third of the height of the specimen after compaction. The end surface of each layer was notched with a spatula or similar tool to ensure close contact with the layer above. After compacting three layers, the collar was removed and the excess soil on top of the mold was carefully scraped away with a straight edge. Holes on the surface caused by sand particles, etc. were filled with fine-grained improved soil and the surface was smoothed to the same height as the top surface of the mold.

[0043] The specimens of Examples 1 to 3 thus prepared were covered with polyethylene film, tied tightly with rubber bands to prevent the surface from drying, and left to cure until the next day. After one day of ageing, the specimens were removed from the mold and sealed and cured in a constant temperature and humidity chamber at a temperature of 20±3°C and a relative humidity of 95% or higher to prevent moisture evaporation.

[0044] [Comparative Examples 1 to 3] 1m of the above clayey soil 3 Test specimens for Comparative Examples 1 to 3 were prepared in the same manner as in Example 1, except that the above cement-based solidification materials were mixed in the amounts shown in Table 1, and the steps up to sealing curing were carried out in the same manner as in Example 1.

[0045] <Uniaxial compressive strength of the ground> The unconfined compressive strength of the ground was measured in accordance with the standard test method prescribed by the Japan Cement Association, "Test Method for Strength of Improved Soils with Cement-Based Solidification Materials L-01:2006." Specifically, unconfined compression tests were conducted on sealed and cured specimens of Examples 1 to 3 and Comparative Examples 1 to 3 after 7 days of age in accordance with the method described in JIS A1216:1998, "Unconfined Compression Test Method for Soil." The unconfined compressive strength was calculated as the arithmetic average of the measurement results for three specimens under the same conditions. The results are shown in Figure 1. 1 is a graph showing the relationship between the amount of cement-based solidification material added and the unconfined compressive strength of the test specimens of Examples 1 to 3 and Comparative Examples 1 to 3. The solid line in Fig. 1 shows the results of Examples 1 to 3, and the dotted line shows the results of Comparative Examples 1 to 3.

[0046] [Examples 4 to 7] [Materials used] <Sat> Clayey soil (uniaxial compressive strength 29kN / m 2 )

[0047] Mixtures 4 to 7 were produced by mixing the same biochar as in Example 1 with the same mass shown in Table 2 as in Example 1 and the same cement-based solidification material as in Example 1 with the same mass shown in Table 2. Then, the clayey soil was used to prepare mixtures 4 to 7. 3 Test specimens of Examples 4 to 7 were prepared in the same manner as in Example 1, except that Mixtures 4 to 7 were mixed in the same manner as in Example 1, and the steps up to sealing and curing were carried out in the same manner as in Example 1.

[0048] [Table 2]

[0049] [Comparative Examples 4 to 7] 1m of the above clayey soil 3 Test specimens for Comparative Examples 4 to 7 were prepared in the same manner as in Example 4, except that the above cement-based solidification materials were mixed in the amounts shown in Table 2, and the steps up to sealing curing were carried out in the same manner as in Example 4.

[0050] For the sealed cured specimens of Examples 4 to 7 and Comparative Examples 4 to 7 after 7 days of age, an unconfined compression test was carried out in the same manner as in Example 1, and the unconfined compressive strength was calculated in the same manner as in Example 1. The results are shown in Figure 2. 2 is a graph showing the relationship between the amount of cement-based solidification material added and the unconfined compressive strength of the test specimens of Examples 4 to 7 and Comparative Examples 4 to 7. The solid line in Fig. 2 shows the results of Examples 4 to 7, and the dotted line shows the results of Comparative Examples 4 to 7.

[0051] The specimens of Examples 1 to 7 had an unconfined compressive strength of 121 kN / m 2 or 29 kN / m 2 1m of clayey soil 3The specimens were 7-day-old samples, in which 30 kg to 150 kg of cement-based solidification material was mixed with 5.5 kg to 27 kg of biochar and solidified. Therefore, the specimens of Examples 1 to 7 can offset the carbon dioxide emissions caused by construction by the carbon dioxide emissions fixed in the specimens by the biochar. Moreover, as shown in Figures 1 and 2, it was confirmed that the specimens of Examples 1 to 7 had the same unconfined compressive strength as the 7-day-old specimens of Comparative Examples 1 to 7, in which no biochar was used.

Claims

1. The soil that makes up the ground, a carbon dioxide immobilization material capable of immobilizing carbon dioxide; A construction method in which the ground is solidified by mixing it with one or more ground solidification materials selected from cement and cement-based solidification materials.

2. The construction method according to claim 1 , wherein the carbon dioxide immobilization material is biochar.

3. 1 m ３ 3. The construction method according to claim 2, wherein the amount of the carbon dioxide immobilization material used relative to the soil is 5 kg to 150 kg.

4. 3. The construction method according to claim 2, wherein the amount of the carbon dioxide immobilized material used is 18 kg to 100 kg per 100 kg of the ground solidification material.

5. The construction method according to claim 1 , further comprising the steps of: mixing the carbon dioxide immobilization material and the ground solidification material to form a mixture; and then mixing the mixture with the soil.

6. The soil that makes up the ground, a carbon dioxide immobilization material capable of immobilizing carbon dioxide; A method for reducing carbon dioxide emissions in a construction method in which the ground is solidified by mixing one or more ground solidification materials selected from cement and cement-based solidification materials, The carbon dioxide emissions resulting from construction can be offset by the carbon dioxide emissions fixed by the carbon dioxide immobilization material.

Images