A kind of all-solid waste carbon-fixing prestressed concrete hollow slab and preparation method thereof

Abstract

The invention discloses a method for all-solid waste carbon fixation prestressed green concrete, the method comprising: separately dry-grinding 50-65 parts of copper slag, 20-30 parts of wollastonite tailings powder and 15-20 parts of carbide slag by weight, and then sieving to obtain a mixed powder with a particle size of 20-40 μm; mixing the mixed powder and water in a weight ratio of 1:2 and wet-grinding with 2-5 parts of polycarboxylic acid water reducer, 1-4 parts of magnesium chloride, 0.3-0.8 parts of cyanoacetic acid, and 170-230 parts of copper slag fine aggregate under the condition of passing CO2 gas to obtain mortar; mixing the mortar with 255-345 parts of crushed stone with a particle size of 6-25 mm, and then vibrating, forming and curing to obtain a prestressed concrete hollow slab. The invention uses copper slag, wollastonite tailings and carbide slag as cementitious materials and copper slag as fine aggregate, achieving the effect of all-solid waste replacement, and has energy saving, emission reduction, low carbon and environmental protection effects.

Description

Technical Field

[0001] The present invention relates to the technical field of building materials, and in particular to a method for preparing all-solid waste carbon-fixing prestressed concrete. Background Art

[0002] The main harm of carbon dioxide to the environment lies in the greenhouse effect. Carbon dioxide is the main gas that causes the greenhouse effect. The greenhouse effect causes global temperatures to rise, which will lead to melting glaciers, rising sea levels, flooding some coastal cities, and causing land desertification and reduced agricultural production. Therefore, reducing carbon emissions is urgent.

[0003] The natural types of wollastonite ore are usually skarn-type ore and wollastonite-quartz-calcite ore. There are a lot of wollastonite tailings in the wollastonite mining area, and the value of the tailings is not fully utilized. On the other hand, there is no suitable treatment method for these tailings waste, so they can only be piled up at will, which not only occupies land, but also pollutes water sources and the environment. It is a typical bulk solid waste.

[0004] The Chinese invention patent application with publication number CN 113443878 A. discloses an ultra-high performance concrete hollow slab and a preparation method thereof, which uses silicate cement, silica fume and fly ash to prepare cementitious materials. The invention realizes the recycling of solid waste resources to a certain extent, but the use of silicate cement increases carbon dioxide emissions and does not achieve the effect of carbon fixation, which is not conducive to promotion in future production.

[0005] Therefore, it is necessary to develop a method for efficiently utilizing waste slag resources and fixing carbon to prepare concrete hollow slabs. Summary of the invention

[0006] The purpose of the present invention is to provide a full solid waste solid carbon prestressed concrete hollow slab and a preparation method thereof, using copper slag, wollastonite tailings, and carbide slag as cementitious materials, and copper slag as fine aggregate, thereby achieving the effect of full solid waste replacement, and having energy saving, emission reduction, and low-carbon and environmental protection effects.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] In a first aspect of the present invention, a method for preparing all-solid waste carbon-fixing concrete is provided, the method comprising:

[0009] 50-65 parts of copper slag, 20-30 parts of wollastonite tailings powder and 15-20 parts of carbide slag are dry-ground separately by weight, and then sieved and mixed to obtain powder with a particle size of 20-40 μm;

[0010] The untreated copper slag is screened to obtain copper slag fine aggregate with a particle size of 0.5 to 4.75 mm;

[0011] The powder and water are mixed in a weight ratio of 1:2 and mixed with 2-5 parts by weight of polycarboxylic acid water reducer, 1-4 parts by weight of magnesium chloride, 0.3-0.8 parts by weight of cyanoacetic acid, and 170-230 parts by weight of the copper slag fine aggregate under a CO 2 Wet grinding under gas conditions to obtain mortar;

[0012] The mortar is mixed with 255-345 parts by weight of crushed stone with a particle size of 6-25 mm, and then vibrated, formed and cured to obtain concrete.

[0013] Furthermore, the wet grinding conditions are: at 35-45° C., carbon dioxide is introduced, and the rotation speed of the wet grinding is 350-400 r / min.

[0014] Furthermore, the copper slag is waste slag produced in the copper smelting process; the chemical composition of the copper slag includes, by mass fraction: 30%≤SiO 2 ≤40%, 5%≤CaO≤10%, 1%≤MgO≤5%, 2%≤Al 2 O 3 ≤4%, iron 27%~35% and zinc 2%~3%.

[0015] Furthermore, the polycarboxylate water reducer is selected from JGT 223-2017 polycarboxylate high performance water reducer.

[0016] In a second aspect of the present invention, an all-solid waste carbon-fixing concrete prepared by the method is provided.

[0017] In the third aspect of the present invention, a full-solid waste carbon fixation prestressed concrete hollow slab is provided. The hollow slab is a fully enclosed structure, the outer wall of the hollow slab is formed by the full-solid waste carbon fixation concrete, and the interior is a foam board.

[0018] One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:

[0019] 1. The present invention uses copper slag, wollastonite tailings and carbide slag as cementitious materials and copper slag as fine aggregate, thus achieving the effect of full solid waste replacement, and has the effects of energy saving, emission reduction, low carbon and environmental protection.

[0020] 2. In the process of co-carbonization, the surface of the copper slag aggregate is carbonized and forms a silicon-rich layer. In the subsequent process of preparing the hollow board, the surface layer can react with the carbide slag to generate hydrated calcium silicate, which can be tightly combined with the matrix. This solves the problem of weak transition zone between the matrix and the aggregate interface and low mechanical properties in the existing system.

[0021] 3. For copper slag powder and wollastonite tailings powder, the present invention wet-grinds and carbonizes them. At the same time, under the action of cyanoacetic acid, the carbonization efficiency is greatly improved, and a large amount of silicon dioxide is released, which can react with carbide slag. No cement is required, and a higher strength can be achieved in the case of all solid waste. Magnesium chloride promotes the conversion of calcium carbonate into aragonite whiskers, which serves the purpose of increasing flexural toughness. No additional fiber is required for all-solid waste carbon-fixed prestressed concrete hollow slabs, and the purpose of low-cost toughening can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0023] Figure 1 The present invention is a flow chart of the preparation method. DETAILED DESCRIPTION

[0024] The present invention will be described in detail below in conjunction with specific implementations and examples, and the advantages and various effects of the present invention will be more clearly presented. It should be understood by those skilled in the art that these specific implementations and examples are used to illustrate the present invention, rather than to limit the present invention.

[0025] Throughout the specification, unless otherwise specifically stated, the terms used herein should be understood as meanings commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art to which the present invention belongs. In the event of a conflict, the present specification takes precedence.

[0026] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or obtained by existing methods.

[0027] Therefore, according to a typical implementation of an embodiment of the present invention, a method for preparing all-solid waste carbon-fixing prestressed concrete is provided, the method comprising:

[0028] Step S1, 50-65 parts of copper slag, 20-30 parts of wollastonite tailings powder and 15-20 parts of carbide slag by weight are dry-ground separately, and then sieved and mixed to obtain a mixed powder with a particle size of 20-40 μm;

[0029] In the step S1,

[0030] Since the hardness of copper slag, wollastonite tailing powder and carbide slag is different, the three are dry-ground separately, and sieved to obtain copper slag powder, wollastonite tailing powder and carbide slag powder with a particle size of 20 to 40 μm, and the three powders are mixed to obtain a mixed powder;

[0031] The copper slag is waste slag produced in the copper smelting process; the main chemical composition of the copper slag obtained is: 30%≤SiO 2 ≤40%, 5%≤CaO≤10%, 1%≤MgO≤5%, 2≤Al 2 O 3 ≤4%, in addition, there is a large amount of iron 27% ~ 35% and a small amount of zinc 2% ~ 3%. The main ore is fayalite (containing 90% FeSiO 4 ), black in color, with a specific surface area of ​​400-500m 2 / kg.

[0032] The wollastonite tailings powder is white with a slight gray or red color, and is in the form of flakes, radials or fibers. Main chemical components: 43.35%≤CaO≤48.25%, 51.75%≤SiO 2 ≤56.65%.

[0033] Step S2, screening the untreated copper slag to obtain copper slag fine aggregate with a particle size of 0.5 to 4.75 mm;

[0034] Copper slag fine aggregate with a particle size of 0.5 to 4.75 mm can act as a grinding medium in the subsequent wet grinding process.

[0035] Step S3, the mixed powder and water are mixed in a weight ratio of 1:2, and the mixed powder is mixed with 2-5 parts of polycarboxylic acid water reducer, 1-4 parts of magnesium chloride, 0.3-0.8 parts of cyanoacetic acid, and 170-230 parts of the copper slag fine aggregate, and then CO is introduced into the mixture. 2 Wet grinding under gas conditions to obtain mortar;

[0036] In the step S3,

[0037] The wet grinding conditions are: introducing carbon dioxide at 35-45°C. If the temperature is too low, the hydration will be slowed down, which is not conducive to the formation of hydration products. If the temperature is too high, the water in the mill will evaporate, which is not conducive to wet grinding and thus reduces the dissolution of ions.

[0038] The speed of wet grinding is 350-400r / min. If the speed is less than 350r / min, the balls in the ball mill are lifted to a small height, and the balls slide down from the top of the ball load due to their own gravity, in a falling state. At this time, the impact force of the balls is very small, but the grinding effect is very strong. The ore is mainly ground and crushed, and the grinding effect is not high; if it is greater than 400r / min, the steel balls rotate with the cylinder without falling, and are in a centrifugal operation state. At this time, the steel balls have no impact effect, the grinding effect is also very small, and the mill consumes a lot of energy and has a small output.

[0039] The polycarboxylate water reducer is selected from JGT 223-2017 polycarboxylate high performance water reducer. The polycarboxylate water reducer, magnesium chloride and cyanoacetic acid have good dispersion function during wet grinding and double acceleration effect on carbonization.

[0040] Copper slag powder, wollastonite tailings and copper slag aggregate are wet carbonized together in a stirred mill. No additional grinding media is needed because the copper slag aggregate can act as a grinding medium.

[0041] The role of cyanoacetic acid is to make the liquid phase environment weakly acidic, which is conducive to the dissolution of iron phase in fayalite and calcium in wollastonite. It can achieve a large dissolution of silicon and provide sufficient silicon phase for subsequent reactions. In addition, cyano has a strong complexing effect on divalent iron ions (iron in fayalite), so it has a double acceleration effect on the carbonization of fayalite.

[0042] Step S4, mixing the mortar and 255-345 parts by weight of crushed stone with a particle size of 6-25 mm, and then vibrating, molding, and curing to obtain a prestressed concrete hollow slab.

[0043] The above steps S1 to S4 are all in parts by weight.

[0044] According to another typical implementation of the embodiments of the present invention, there is provided an all-solid waste carbon-fixing prestressed concrete obtained by the method.

[0045] According to another typical implementation of an embodiment of the present invention, a full-solid waste carbon-fixing prestressed concrete hollow slab is provided, wherein the hollow slab is a fully enclosed structure, the outer wall of the hollow slab is formed by the full-solid waste carbon-fixing prestressed concrete, and the interior is a foam board.

[0046] The thickness of the outer wall is 2 to 3 cm, and the thickness of the foam board is 10 to 20 cm.

[0047] Before pouring the prestressed concrete hollow slab, the ballast bed surface must be polished and hardened; the steel strands must be laid on the ballast bed; the steel strands must be anchored and tensioned, a protective layer must be placed under the steel strands, embedded parts must be placed, and the steel strands must be placed in the buckles of the embedded parts, and water must be sprayed on the ballast bed surface. After that, the prestressed concrete hollow slab is obtained through pouring, vibrating, molding, and curing.

[0048] The preparation method of all-solid waste carbon-fixing prestressed concrete of the present application will be described in detail below with reference to embodiments, comparative examples and experimental data.

[0049] Example 1: A full solid waste carbon fixation prestressed concrete hollow slab and its preparation method

[0050] This embodiment provides a full solid waste carbon fixation prestressed concrete hollow slab, and the method includes:

[0051] 65 parts of copper slag, 20 parts of wollastonite tailings powder and 15 parts of carbide slag are dry-ground separately by weight, and then sieved and mixed to obtain a mixed powder with a particle size of 20 to 40 μm;

[0052] The untreated copper slag is screened to obtain copper slag fine aggregate with a particle size of 0.5 to 4.75 mm;

[0053] The mixed powder and water were mixed in a weight ratio of 1:2 and mixed with 5 parts of polycarboxylic acid water reducer, 4 parts of magnesium chloride, 0.8 parts of cyanoacetic acid and 200 parts of copper slag fine aggregate under a CO 2 Wet grinding under gas conditions to obtain mortar;

[0054] The mortar is mixed with 300 parts of crushed stones with a particle size of 6 to 25 mm, and then vibrated, formed and cured to obtain concrete.

[0055] A fully solid waste carbon-fixing prestressed concrete hollow slab, the hollow slab is a fully enclosed structure, the outer wall of the hollow slab is formed by the fully solid waste carbon-fixing concrete, and the interior is a foam board. Before pouring the prestressed concrete hollow slab, the ballast bed surface is ground, polished and hardened; the steel strands are laid on the ballast bed; the steel strands are anchored, the steel strands are tensioned, a protective layer is placed under the steel strands, embedded parts are placed, the steel strands are placed in the buckles of the embedded parts, and water is sprayed on the ballast bed surface at the same time. After pouring, vibrating, molding and curing, the prestressed concrete hollow slab is obtained.

[0056] Example 2: A full solid waste carbon fixation prestressed concrete hollow slab and its preparation method

[0057] This embodiment provides a full solid waste carbon fixation prestressed concrete hollow slab, and the method includes:

[0058] 60 parts of copper slag, 20 parts of wollastonite tailings powder and 20 parts of carbide slag are dry-ground separately by weight, and then sieved and mixed to obtain a mixed powder with a particle size of 20 to 40 μm;

[0059] The untreated copper slag is screened to obtain copper slag fine aggregate with a particle size of 0.5 to 4.75 mm;

[0060] The mixed powder and water were mixed in a weight ratio of 1:2 and mixed with 4 parts of polycarboxylic acid water reducer, 4 parts of magnesium chloride, 0.6 parts of cyanoacetic acid and 200 parts of copper slag fine aggregate under a CO 2 Wet grinding under gas conditions to obtain mortar;

[0061] The mortar was mixed with 300 parts of crushed stone with a particle size of 6 to 25 mm, and then vibrated, formed and cured to obtain concrete. The method of Example 1 was used to obtain a full-solid waste solid carbon prestressed concrete hollow slab.

[0062] Example 3: A full solid waste carbon fixation prestressed concrete hollow slab and its preparation method

[0063] This embodiment provides a full solid waste carbon fixation prestressed concrete hollow slab, and the method includes:

[0064] 60 parts of copper slag, 25 parts of wollastonite tailings powder and 15 parts of carbide slag are dry-ground separately by weight, and then sieved and mixed to obtain a mixed powder with a particle size of 20 to 40 μm;

[0065] The untreated copper slag is screened to obtain copper slag fine aggregate with a particle size of 0.5 to 4.75 mm;

[0066] The mixed powder and water were mixed in a weight ratio of 1:2 and mixed with 4 parts of polycarboxylic acid water reducer, 3 parts of magnesium chloride, 0.6 parts of cyanoacetic acid and 200 parts of copper slag fine aggregate under a CO 2 Wet grinding under gas conditions to obtain mortar;

[0067] The mortar was mixed with 300 parts of crushed stone with a particle size of 6 to 25 mm, and then vibrated, formed and cured to obtain concrete. The method of Example 1 was used to obtain a full-solid waste solid carbon prestressed concrete hollow slab.

[0068] Example 4: A full solid waste carbon fixation prestressed concrete hollow slab and its preparation method

[0069] This embodiment provides a full solid waste carbon fixation prestressed concrete hollow slab, and the method includes:

[0070] 55 parts of copper slag, 25 parts of wollastonite tailings powder and 20 parts of carbide slag are dry-ground separately by weight, and then sieved and mixed to obtain a mixed powder with a particle size of 20 to 40 μm;

[0071] The untreated copper slag is screened to obtain copper slag fine aggregate with a particle size of 0.5 to 4.75 mm;

[0072] The mixed powder and water were mixed in a weight ratio of 1:2 and mixed with 3 parts of polycarboxylic acid water reducer, 3 parts of magnesium chloride, 0.4 parts of cyanoacetic acid and 200 parts of copper slag fine aggregate under a CO 2 Wet grinding under gas conditions to obtain mortar;

[0073] The mortar was mixed with 300 parts of crushed stone with a particle size of 6 to 25 mm, and then vibrated, formed and cured to obtain concrete. The method of Example 1 was used to obtain a full-solid waste solid carbon prestressed concrete hollow slab.

[0074] Example 5: A full solid waste carbon fixation prestressed concrete hollow slab and its preparation method

[0075] This embodiment provides a full solid waste carbon fixation prestressed concrete hollow slab, and the method includes:

[0076] 55 parts of copper slag, 30 parts of wollastonite tailings powder and 15 parts of carbide slag by weight are dry-ground separately, and then sieved and mixed to obtain a mixed powder with a particle size of 20 to 40 μm;

[0077] The untreated copper slag is screened to obtain copper slag fine aggregate with a particle size of 0.5 to 4.75 mm;

[0078] The mixed powder and water were mixed in a weight ratio of 1:2 and mixed with 3 parts of polycarboxylic acid water reducer, 2 parts of magnesium chloride, 0.4 parts of cyanoacetic acid, and 170 parts of the copper slag fine aggregate under a CO 2 Wet grinding under gas conditions to obtain mortar;

[0079] The mortar was mixed with 255 parts of crushed stone with a particle size of 6 to 25 mm, and then vibrated, formed and cured to obtain concrete. The method of Example 1 was used to obtain a full-solid waste solid carbon prestressed concrete hollow slab.

[0080] Example 6: A full solid waste carbon fixation prestressed concrete hollow slab and its preparation method

[0081] This embodiment provides a full solid waste carbon fixation prestressed concrete hollow slab, and the method includes:

[0082] 50 parts of copper slag, 30 parts of wollastonite tailings powder and 20 parts of carbide slag are dry-ground separately by weight, and then sieved and mixed to obtain a mixed powder with a particle size of 20 to 40 μm;

[0083] The untreated copper slag is screened to obtain copper slag fine aggregate with a particle size of 0.5 to 4.75 mm;

[0084] The mixed powder and water were mixed in a weight ratio of 1:2 and mixed with 2 parts of polycarboxylic acid water reducer, 1 part of magnesium chloride, 0.3 parts of cyanoacetic acid, and 230 parts of copper slag fine aggregate under a CO 2 Wet grinding under gas conditions to obtain mortar;

[0085] The mortar was mixed with 345 parts of crushed stone with a particle size of 6 to 25 mm, and then vibrated, formed and cured to obtain concrete. The method of Example 1 was used to obtain a full-solid waste solid carbon prestressed concrete hollow slab.

[0086] Comparative Example 1

[0087] In this comparative example, magnesium chloride is not added, and the specific preparation method is as follows:

[0088] 65 parts of copper slag, 20 parts of wollastonite tailings powder and 15 parts of carbide slag are dry-ground separately by weight, and then sieved and mixed to obtain a mixed powder with a particle size of 20 to 40 μm;

[0089] The untreated copper slag is screened to obtain copper slag fine aggregate with a particle size of 0.5 to 4.75 mm;

[0090] The mixed powder and water were mixed in a weight ratio of 1:2 and mixed with 5 parts of polycarboxylic acid water reducer, 0.8 parts of cyanoacetic acid and 200 parts of copper slag fine aggregate under a CO 2 Wet grinding under gas conditions to obtain mortar;

[0091] The mortar was mixed with 300 parts of crushed stone with a particle size of 6 to 25 mm, and then vibrated, formed and cured to obtain concrete. The method of Example 1 was used to obtain a full-solid waste solid carbon prestressed concrete hollow slab.

[0092] Comparative Example 2

[0093] There is no cyanoacetic acid in this comparative example, and the specific preparation method is as follows:

[0094] This embodiment provides a full solid waste carbon fixation prestressed concrete hollow slab, and the method includes:

[0095] 65 parts of copper slag, 20 parts of wollastonite tailings powder and 15 parts of carbide slag are dry-ground separately by weight, and then sieved and mixed to obtain a mixed powder with a particle size of 20 to 40 μm;

[0096] The untreated copper slag is screened to obtain copper slag fine aggregate with a particle size of 0.5 to 4.75 mm;

[0097] The mixed powder and water were mixed in a weight ratio of 1:2 and mixed with 5 parts of polycarboxylate water reducer, 4 parts of magnesium chloride and 200 parts of copper slag fine aggregate under a CO 2 Wet grinding under gas conditions to obtain mortar;

[0098] The mortar was mixed with 300 parts of crushed stone with a particle size of 6 to 25 mm, and then vibrated, formed and cured to obtain concrete. The method of Example 1 was used to obtain a full-solid waste solid carbon prestressed concrete hollow slab.

[0099] Experimental Example 1

[0100] For the convenience of comparison, the preparation parameters of Examples 1 to 6 and Comparative Examples 1 to 2 are listed as follows:

[0101] Table 1

[0102]

[0103]

[0104] After each group was cured and formed, the slump, compressive strength and carbon fixation rate of the slurry were tested according to GB / T14040-2007 "Standard Specification for Prestressed Concrete". The specific results are shown in Table 2 below.

[0105] Table 2

[0106]

[0107] From Table 2, we can see that:

[0108] Compared with Comparative Example 1-Comparative Example 2, the prestressed concrete hollow slabs prepared by Example 1-Example have better compressive strength, slump, and slurry carbon fixation rate. At the same time, since magnesium chloride promotes the conversion of calcium carbonate into aragonite whiskers, it has the purpose of increasing flexural resistance and toughness, and no additional fiber needs to be added. It can be applied to the production of building floor boards, floor panels, wall panels, sound insulation boards, and cover boards.

[0109] Finally, it should be noted that the terms "comprises," "includes," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements that are inherent to such process, method, article, or apparatus.

[0110] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0111] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for all-solid waste carbon fixation concrete, characterized in that: The method comprises: 50-65 parts of copper slag, 20-30 parts of wollastonite tailings powder and 15-20 parts of carbide slag are dry-ground separately by weight, and then sieved and mixed to obtain a mixed powder with a particle size of 20-40 μm; The untreated copper slag is screened to obtain copper slag fine aggregate with a particle size of 0.5 to 4.75 mm; The mixed powder and water are mixed in a weight ratio of 1:2, and wet-grinded with 2 to 5 parts by weight of a polycarboxylate water-reducing agent, 1 to 4 parts by weight of magnesium chloride, 0.3 to 0.8 parts by weight of cyanoacetic acid, and 170 to 230 parts by weight of the copper slag fine aggregate under the condition of passing CO2 gas to obtain mortar; The mortar is mixed with 255-345 parts by weight of crushed stone with a particle size of 6-25 mm, and then vibrated, formed and cured to obtain all-solid waste carbon-fixing concrete.

2. The method according to claim 1, characterized in that The wet grinding conditions are: introducing carbon dioxide at 35-45° C. and the rotating speed of the wet grinding is 350-400 r / min.

3. The method according to claim 1, characterized in that The copper slag is waste slag produced in the copper smelting process; the chemical composition of the copper slag includes, by mass percentage: 30%≤SiO2≤40%, 5%≤CaO≤10%, 1%≤MgO≤5%, 2%≤Al2O3≤4%, 27%-35% iron and 2%-3% zinc.

4. The method according to claim 1, characterized in that: The polycarboxylate water reducer is selected from JGT 223-2017 polycarboxylate high performance water reducer.

5. An all-solid waste carbon fixation concrete prepared by the method described in any one of claims 1 to 4.

6. A full solid waste carbon fixation prestressed concrete hollow slab, characterized in that: The hollow slab is a fully enclosed structure. The outer wall of the hollow slab is formed by the all-solid waste carbon fixation concrete described in claim 5, and the interior is a foam board. Before pouring the prestressed concrete hollow slab, the ballast bed surface is ground, polished and hardened; the steel strands are pulled and laid on the ballast bed; the steel strands are anchored, tensioned, a protective layer is placed under the steel strands, embedded parts are placed, the steel strands are placed in the buckles of the embedded parts, and the ballast bed surface is sprayed with water. After pouring, vibrating, molding and curing, the all-solid waste carbon fixation prestressed concrete hollow slab is obtained.

7. The all-solid waste carbon fixation prestressed concrete hollow slab according to claim 6, characterized in that: The thickness of the outer wall is 2 to 3 cm, and the thickness of the foam board is 10 to 20 cm.

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