Carbonized steel slag-commercial mixing station solid waste-based autoclaved aerated concrete and preparation method thereof

Abstract

The invention discloses carbonized steel slag-commercial mixing station solid waste-based autoclaved aerated concrete which is prepared from the following raw materials in percentage by mass: 30%-40% of carbonized steel slag powder, 20%-30% of carbonized commercial mixing station solid waste micro powder, 20%-30% of cement, 4%-12% of lime and 2%-6% of building gypsum; the admixture comprises a water reducing agent and aluminum paste, the dosage of the water reducing agent is 0.1%-0.5% of the total mass of the cementing material, and the dosage of the aluminum paste is 0.08%-0.12% of the total mass of the cementing material. The characteristics of potential activity and high alkalinity of the steel slag and the commercial mixing station solid waste are utilized, carbonization modification is performed, so that the steel slag and the commercial mixing station solid waste replace calcium raw materials and siliceous raw materials to serve as main raw materials for preparing the autoclaved aerated concrete, the production cost of the autoclaved aerated concrete is remarkably reduced, and the production cost is reduced. And the problems of disposal and utilization of solid wastes such as steel slag and commercial mixing station solid wastes are solved.

Description

Technical Field

[0001] The invention belongs to the field of resource recycling, and specifically relates to a carbonized steel slag-commercial mixing station solid waste-based autoclaved aerated concrete and a preparation method thereof. Background Art

[0002] With the continuous progress of wall materials in my country and the increasing awareness of environmental protection, traditional clay bricks are gradually replaced by high-performance and more environmentally friendly aerated concrete blocks. The development of solid waste raw materials is an important manifestation of the core technology of modern aerated concrete blocks. Using steel slag powder as a calcium raw material for aerated concrete is in line with the theme of energy conservation, environmental protection and sustainable development in my country, and is in line with the development trend of modern concrete. In recent years, scholars have continued to conduct in-depth research on the secondary utilization of steel slag. The potential economic benefits of steel slag grinding to replace calcium raw materials in aerated concrete have been continuously explored. Steel companies have also continuously improved steel production processes and steel slag treatment technologies, and successfully applied magnetic separation technology to tailings treatment, so that steel slag can be better utilized as a resource. The conditions for replacing part of cement with steel slag grinding to prepare steel slag cement concrete are already in place.

[0003] Commercial concrete mixing stations are the main processing and production bases for ready-mixed concrete, and most of them are located in urban-rural fringe areas and around large construction projects. The cleaning of transport tankers at large commercial concrete mixing stations and the purification of sewage in the station area will produce a large amount of strongly alkaline waste mud, the main components of which include cement hydration products, unhydrated cement particles, mineral powder, fly ash and a small amount of clay. The pH value is usually around 13, which will pose an environmental risk if not disposed of in time.

[0004] With the increasing attention paid by the state to the disposal and utilization of industrial bulk solid waste and the continuous development of autoclaved aerated concrete technology, many scholars have studied the preparation of autoclaved aerated concrete with steel slag. However, the early activity of steel slag powder is low and there is still a problem of poor stability, which makes it difficult to achieve industrial production. This problem needs to be solved urgently. There are few reports on the preparation of autoclaved aerated concrete with solid waste from commercial mixing stations. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a carbonized steel slag-commercial concrete station solid waste-based autoclaved aerated concrete and a preparation method thereof in view of the deficiencies in the above-mentioned prior art. The potential activity and high alkalinity of steel slag and commercial concrete station solid waste are utilized, and carbonization modification is performed, so as to replace calcium raw materials and siliceous raw materials as the main raw materials for preparing autoclaved aerated concrete, thereby significantly reducing the production cost of autoclaved aerated concrete and solving the problem of disposal and utilization of solid wastes such as steel slag and commercial concrete station solid waste.

[0006] The technical solution adopted by the present invention to solve the above-mentioned problems is:

[0007] A kind of autoclaved aerated concrete based on carbonized steel slag - solid waste from commercial concrete mixing stations, the raw materials of which include cementitious materials and admixtures. The cementitious materials include, by mass percentage: 30% - 40% of carbonized steel slag powder, 20% - 30% of carbonized solid waste fine powder from commercial concrete mixing stations, 20 - 30% of cement, 4% - 12% of lime, and 2% - 6% of building gypsum; the admixtures include water - reducing agent and aluminum paste. The dosage of the water - reducing agent is 0.1% - 0.5% of the total mass of the cementitious materials, and the dosage of the aluminum paste is 0.08% - 0.12% of the total mass of the cementitious materials.

[0008] According to the above - mentioned scheme, the carbonized steel slag is obtained by drying the carbon steel slag from converter steelmaking, then performing roll - pressing treatment, and then ball - milling to a specific surface area of 350 - 400 m 2 / kg, and then placing it in a carbonization box for carbonization. Among them, the carbonization conditions are: carbonization pressure 0.1 - 0.2 MPa, carbonization humidity 70% - 80%, temperature 15 - 25 °C, and CO2 concentration 15% - 25%.

[0009] According to the above - mentioned scheme, the carbonized solid waste fine powder from commercial concrete mixing stations is obtained by drying the waste sludge from commercial concrete mixing stations, then performing roll - pressing treatment, and then ball - milling to a specific surface area of 350 - 400 m 2 / kg, and then placing it in a carbonization box for carbonization. Among them, the carbonization conditions are: carbonization pressure 0.1 - 0.2 MPa, carbonization humidity 70% - 80%, temperature 15 - 25 °C, and CO2 concentration 15% - 25%.

[0010] According to the above - mentioned scheme, the cement is ordinary Portland cement, such as P·O42.5 Portland cement.

[0011] According to the above - mentioned scheme, the lime is commercially available quicklime, with an effective calcium oxide content of 72%, a residue on 75 - μm sieve less than 15%, a digestion time of 5 min, and a digestion temperature of 80 °C.

[0012] According to the above - mentioned scheme, the mass percentage of lime is preferably 4% - 6%; the mass percentage of building gypsum is preferably 4% - 6%; the dosage of the water - reducing agent is preferably 0.1% - 0.2% of the total mass of the cementitious materials.

[0013] According to the above - mentioned scheme, the water - reducing agent is a polycarboxylate water - reducing agent mother liquor, with a solid content of 35 - 45%.

[0014] According to the above - mentioned scheme, the main component of the building gypsum is calcium sulfate dihydrate CaSO4·2H2O, with a content of ≥93%.

[0015] According to the above - mentioned scheme, the aluminum paste is a water - based aluminum powder paste, with an active aluminum content of ≥70%.

[0016] The present invention also provides a preparation method of the above - mentioned autoclaved aerated concrete based on carbonized steel slag - solid waste from commercial concrete mixing stations, and the specific steps are as follows:

[0017] (1) Weigh 30% - 40% of carbonized steel slag powder, 20% - 30% of carbonized waste micro - powder from commercial concrete mixing plants, 20 - 30% of cement, 4% - 12% of lime, and 2% - 6% of building gypsum according to the composition and mass percentage of the binder material; and weigh 0.1% - 0.5% of water - reducing agent and 0.08% - 0.12% of aluminum paste according to the percentage of the total mass of the binder material.

[0018] (2) Add the carbonized steel slag powder, carbonized waste micro - powder from commercial concrete mixing plants, cement, lime, and building gypsum into a mixer and stir for 2 - 5 minutes to mix evenly, obtaining a mixed dry powder.

[0019] (3) Control the water - to - material mass ratio to be 0.5 - 0.7. After dissolving the water - reducing agent and aluminum paste in water (i.e., the mass of water: the total mass of the water - reducing agent and aluminum paste = 0.5 - 0.7), add it to the mixed dry powder obtained in step (2), and continue to stir for 1 - 3 minutes to mix evenly, obtaining a slurry.

[0020] (4) Pour and mold the slurry obtained in step (3), and after static pre - curing at a temperature of 60 - 70°C for 5 - 7 hours, demold it, then place it in an autoclave and carry out autoclave curing at a saturated steam pressure of 1.5 MPa for 5 - 7 hours to obtain the finished aerated concrete block, namely the carbonized steel slag - waste - based aerated concrete from commercial concrete mixing plants.

[0021] The performance indicators of the aerated concrete based on steel slag - waste from commercial concrete mixing plants prepared by the above method are as follows: dry density 670 - 703 kg / m 3 (reaching B07 grade), compressive strength not less than 5.4 Mpa (reaching A5.0 grade), drying shrinkage value not exceeding 0.50 mm / m, average mass loss after freezing ≤ 5%, average strength loss ≤ 20%, and thermal conductivity not exceeding 0.16 W / (m·K).

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0023] First of all, starting from the fact that a large amount of strongly alkaline waste mud is generated from the cleaning of transport tank trucks in commercial concrete mixing plants and the sewage purification in the station area, and based on the fact that its main components include cement hydration products, unhydrated cement particles, mineral powder, fly ash, and a small amount of clay, with a relatively high silicon content and a pH value of about 13, while using it as the siliceous raw material in the aerated concrete of the present invention, it provides alkalinity for the reaction environment of preparing autoclaved aerated concrete, making the gas - generating speed and thickening speed of the slurry prepared by compounding with other raw materials more matched, so that the autoclaved aerated concrete block obtained after positive - pressure curing through static curing has a lower dry density and higher compressive strength.

[0024] Second, the present invention uses the carbonized waste micro-powder from commercial concrete mixing plants. Compared with the uncarbonized waste micro-powder from commercial concrete mixing plants, more CaCO3 and amorphous silica gel are generated during the carbonization process, which has better pozzolanic activity. The autoclaved aerated concrete prepared has higher compressive strength, and the carbonized waste from commercial concrete mixing plants can improve the pore structure of autoclaved aerated concrete, thereby making the dry density and compressive strength of the final product autoclaved aerated concrete better.

[0025] Third, the f-CaO, f-MgO, Ca(OH)2 and Mg(OH)2 in steel slag can react with CO2 to form CaC03 or MgC03, and C3S, CaSi03, β-C2S and γ-C2S are carbonized to form amorphous SiO2. The present invention improves the activity of steel slag through carbonization, solves the problem of poor soundness of steel slag, effectively improves the physical strength of aerated concrete blocks, and avoids the problem of block cracking.

[0026] Fourth, compared with traditional calcareous materials, steel slag has certain potential activity and can generate more tobermorite in the reaction system to provide strength support for the blocks. At the same time, the high alkalinity of steel slag and waste micro-powder from commercial concrete mixing plants can make the aluminum paste foam evenly and continuously, and the aerated concrete blocks have uniform foaming and stable density, thereby improving the compressive strength of the product.

[0027] Therefore, the present invention not only solves the problems of disposal and utilization of solid wastes such as steel slag and waste from commercial concrete mixing plants, but also utilizes the potential activity and high alkalinity of steel slag and waste from commercial concrete mixing plants, and modifies them by carbonization, so as to replace calcareous raw materials and siliceous raw materials as the main raw materials for preparing autoclaved aerated concrete. The obtained aerated concrete blocks can reach the grades of A5.0 and B07. Moreover, the present invention can reduce the usage amounts of cement, calcareous raw materials and siliceous raw materials in the raw materials, significantly reduce the production cost of autoclaved aerated concrete, reduce carbon emissions, and has good economic and environmental benefits. Detailed implementation mode

[0028] To better understand the present invention, the content of the present invention will be further clarified below in conjunction with embodiments, but the present invention is not limited to the following embodiments.

[0029] In the following embodiments, the carbonized steel slag powder is obtained by drying the carbon steel slag obtained from converter steelmaking, then performing roll pressing treatment, and then ball milling to a specific surface area of 350 - 400m 2 / kg, and then placing it in a carbonization chamber for carbonization; among them, the carbonization conditions are: carbonization pressure 0.15MPa, carbonization humidity 75% ± 5%, temperature 20°C, and CO2 concentration 20%. Specifically, the main chemical components and their contents (wt%) of the carbonized steel slag powder are shown in Table 1, LOSS is "loss on ignition", and the balance is other extremely trace components that are inevitable.

[0030] In the following examples, the solid waste fine powder of the carbonized commercial concrete mixing plant is obtained by drying the waste mud of the commercial concrete mixing plant, then performing roll pressing treatment, and then ball milling to a specific surface area of 350 - 400 m 2 / kg, and then placing it in a carbonization box for carbonization; among them, the carbonization conditions are: carbonization pressure 0.15 MPa, carbonization humidity 75% ± 5%, temperature 20 °C, CO2 concentration 20%. Specifically, the main chemical components and their contents (wt%) of the carbonized solid waste fine powder of the commercial concrete mixing plant are shown in Table 1. LOSS is "loss on ignition", and the balance is other extremely trace components that are inevitable.

[0031] Table 1 Main chemical compositions of carbonized steel slag powder and carbonized solid waste of commercial concrete mixing plant (%)

[0032] Chemical composition (%) <![CDATA[SiO2]]> <![CDATA[Al2O3]]> <![CDATA[Fe2O3]]> CaO MgO <![CDATA[SO3]]> LOSS Carbonized steel slag powder 13.60 1.41 18.24 45.92 3.71 0.05 16.72 Carbonized waste micro powder from commercial concrete mixing station 57.53 11.29 3.74 12.60 1.51 0.80 12.23

[0033] In the following examples, the water reducing agent is the HL-700 polycarboxylate water reducing agent mother liquor with a solid content of 40 ± 1%; the main component of the building gypsum is calcium sulfate dihydrate CaSO4·2H2O with a content of ≥ 93%; the aluminum paste is the GLS-70 water-based aluminum powder paste with an effective component content of ≥ 70%; the lime is commercially available quicklime with an effective calcium oxide content of 72%, a 75 μm sieve residue of less than 15%, a digestion time of 5 min, and a digestion temperature of 80 °C; the cement used is P·O42.5 ordinary Portland cement, and the main chemical components and their contents (wt%) are shown in Table 2, and the balance is other extremely trace components that are inevitable.

[0034] Table 2

[0035] Chemical composition (%) <![CDATA[SiO2]]> <![CDATA[Al2O3]]> <![CDATA[Fe2O3]]> CaO MgO <![CDATA[SO3]]> <![CDATA[K2O]]> <![CDATA[Na2O]]> LOSS Portland cement 17.76 6.83 4.04 64.62 1.78 3.52 0.29 0.16 0.73

[0036] Examples 1 - 4

[0037] A steam-cured autoclaved aerated concrete based on carbonized steel slag - solid waste of commercial concrete mixing plant, whose raw materials include cementitious materials and admixtures, and the mass percentage content of each raw material is shown in Table 3; among them, the mass percentages of the water reducing agent and the aluminum paste are calculated based on the total mass of the gel materials.

[0038] Table 3 Raw material compositions of steam-cured autoclaved aerated concrete in each example (units are all %)

[0039] Serial number Cement Lime Building gypsum Carbonized steel slag powder Carbonized waste micro powder from commercial concrete mixing station Water reducing agent Aluminum paste Example 1 30 6 4 40 20 0.2 0.1 Example 2 30 5 5 30 30 0.1 0.1 Example 3 25 4 6 35 30 0.1 0.1 Example 4 20 6 4 40 30 0.1 0.1

[0040] The preparation method of the steam-cured autoclaved aerated concrete blocks in Examples 1 - 4 is as follows:

[0041] (1) Weigh carbonized steel slag powder, carbonized solid waste fine powder of commercial concrete mixing plant, cement, lime, building gypsum, water reducing agent and aluminum paste according to the raw materials and their mass percentages in Table 3;

[0042] (2) Add steel slag powder after carbonization, solid waste micro-powder from commercial concrete mixing plants, cement, lime, and building gypsum into a mixer and stir for 3 minutes to mix evenly, obtaining mixed dry powder;

[0043] (3) Control the mass ratio of water to materials to be 0.6. After dissolving water-reducing agent and aluminum paste in water, add them to the mixed dry powder obtained in step (2), and continue to stir for 2 minutes to mix evenly, obtaining a slurry;

[0044] (4) Pour and mold the slurry obtained in step (3), and after static pre-curing at a temperature of 65°C for 6 hours, demold it, then place it in an autoclave and perform autoclave curing at a saturated steam pressure of 1.5 MPa for 6 hours, obtaining finished autoclaved aerated concrete blocks, namely autoclaved aerated concrete based on steel slag after carbonization and solid waste from commercial concrete mixing plants.

[0045] Comparative Example 1

[0046] The difference between Comparative Example 1 and Example 1 is that neither the steel slag powder nor the solid waste micro-powder from commercial concrete mixing plants was carbonized.

[0047] Comparative Example 2

[0048] The difference between Comparative Example 2 and Example 1 is that the steel slag powder was not carbonized.

[0049] Comparative Example 3

[0050] The difference between Comparative Example 3 and Example 1 is that the solid waste micro-powder from commercial concrete mixing plants was not carbonized.

[0051] Performance testing

[0052] Test the autoclaved aerated concrete prepared in each example and comparative example according to the following method, and the test results are shown in Table 4.

[0053] (1) Dry density: Test according to the method of Standard GB / T 11969 - 2020 "Test Methods for Performance of Autoclaved Aerated Concrete", unit kg / m 3 .

[0054] (2) Compressive strength: Test according to the method of Standard GB / T 11969 - 2020 "Test Methods for Performance of Autoclaved Aerated Concrete", unit MPa.

[0055] (3) Dry shrinkage value: Test according to the method of Standard GB / T 11969 - 2020 "Test Methods for Performance of Autoclaved Aerated Concrete", unit mm / m.

[0056] (4) Frost resistance: Test according to the method of Standard GB / T 11969 - 2020 "Test Methods for Performance of Autoclaved Aerated Concrete", unit %.

[0057] (5) Thermal conductivity: Tested according to the method of Standard GB / T 10294-2008 "Determination of Steady-State Thermal Resistance and Related Properties of Thermal Insulation Materials - Guarded Hot Plate Method", with the unit of W / (m·K).

[0058] Table 4 Detection Results of Autoclaved Aerated Concrete Obtained from Each Example and Comparative Example

[0059]

[0060]

[0061] In Comparative Example 1, neither the steel slag powder nor the solid waste fine powder from the commercial concrete mixing station was carbonized. In Comparative Example 2, the steel slag powder was not carbonized. In Comparative Example 3, the solid waste fine powder from the commercial concrete mixing station was not carbonized. Compared with the autoclaved aerated concrete prepared in Example 1, Comparative Examples 1, 2, and 3 had higher dry density and lower compressive strength. This is because the hydration reaction activity of the steel slag powder was significantly enhanced after carbonization, and the pozzolanic activity of the solid waste from the commercial concrete mixing station was significantly enhanced after carbonization. The compressive strength of the autoclaved aerated concrete block increased significantly. After carbonization, the solid waste from the commercial concrete mixing station slightly reduced the alkalinity, making the thickening speed and the starting speed more matched during the block forming process. The obtained autoclaved aerated concrete block had a lower dry density while ensuring the compressive strength. The drying shrinkage value of the autoclaved aerated concrete prepared in Example 1 was higher than that in Comparative Examples 1 and 2, indicating that the content of f-CaO and f-MgO in the steel slag decreased significantly after carbonization, improving the problem of poor soundness of the steel slag and effectively avoiding the cracking of the material caused by the reaction expansion of f-CaO and f-MgO during the later use process. Comparative Examples 1, 2, and 3 had worse frost resistance than the autoclaved aerated concrete prepared in Example 1, indicating that the nucleation ability of the solid waste fine powder from the commercial concrete mixing station was improved after carbonization, and the reaction activity of the steel slag powder and the solid waste fine powder from the commercial concrete mixing station was higher after carbonization, reducing the porosity of the autoclaved aerated concrete. The test results of the thermal conductivity showed that carbonizing the steel slag and the solid waste from the commercial concrete mixing station did not affect the thermal conductivity of the autoclaved aerated concrete block.

[0062] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the inventive concept of the present invention, several improvements and transformations can still be made, and these all belong to the protection scope of the present invention.

Claims

1. A carbonized steel slag-commercial concrete station solid waste-based autoclaved aerated concrete, characterized in that: The raw materials include cementitious materials and admixtures. The cementitious materials include, by mass percentage, 30% to 40% of carbonized steel slag powder, 20% to 30% of carbonized commercial mixing station solid waste powder, 20% to 30% of cement, 4% to 12% of lime, and 2% to 6% of building gypsum; the admixtures include water reducing agent and aluminum paste. The amount of water reducing agent is 0.1% to 0.5% of the total mass of the cementitious materials, and the amount of aluminum paste is 0.08% to 0.12% of the total mass of the cementitious materials.

2. The carbonized steel slag-commercial concrete station solid waste-based autoclaved aerated concrete according to claim 1, characterized in that: The carbonized steel slag is obtained by drying the carbon steel slag obtained by converter steelmaking, rolling it, and then ball milling it to a specific surface area of ​​350-400m 2 / kg, and then placed in a carbonization box for carbonization; wherein the carbonization conditions are: carbonization pressure 0.1-0.2MPa, carbonization humidity 70%-80%, temperature 15-25°C, CO2 concentration 15%-25%.

3. The carbonized steel slag-commercial concrete waste autoclaved aerated concrete according to claim 1, characterized in that: The carbonized commercial mixing station solid waste powder is obtained by drying the commercial mixing station waste mud, rolling it, and then ball milling it to a specific surface area of ​​350-400m 2 / kg, and then placed in a carbonization box for carbonization; wherein the carbonization conditions are: carbonization pressure 0.1-0.2MPa, carbonization humidity 70%-80%, temperature 15-25°C, CO2 concentration 15%-25%.

4. The carbonized steel slag-commercial concrete waste autoclaved aerated concrete according to claim 1, characterized in that: The carbonized steel slag powder has a SiO2 content of 10% to 15%, an Al2O3 content of 1% to 2%, a Fe2O3 content of 17% to 20%, a CaO content of 42% to 48%, and a MgO content of 3% to 5%; the carbonized commercial mixing station solid waste powder has a SiO2 content of 50% to 60%, an Al2O3 content of 10% to 15%, a Fe2O3 content of 3% to 5%, a CaO content of 10% to 15%, and a MgO content of 1% to 5%.

5. The carbonized steel slag-commercial concrete station solid waste-based autoclaved aerated concrete according to claim 1, characterized in that: The lime is quicklime, with an effective calcium oxide content of ≥72%, a 75μm sieve residue of less than 15%, a digestion time of 4 to 6 minutes, and a digestion temperature of 80℃ to 85℃.

6. The carbonized steel slag-commercial concrete station solid waste-based autoclaved aerated concrete according to claim 1, characterized in that: The mass percentage of lime is 4% to 6%, and the mass percentage of building gypsum is 4% to 6%.

7. The carbonized steel slag-commercial concrete waste autoclaved aerated concrete according to claim 1, characterized in that: The dosage of water reducing agent is 0.1% to 0.2% of the total mass of cementitious materials.

8. The carbonized steel slag-commercial concrete station solid waste-based autoclaved aerated concrete according to claim 1, characterized in that: The water reducer is a polycarboxylate water reducer mother liquor with a solid content of 35-45%; the main component of the building gypsum is calcium sulfate dihydrate CaSO4·2H2O with a content of ≥93%; the aluminum paste is a water-based aluminum powder paste with an active aluminum content of ≥70%.

9. The method for preparing carbonized steel slag-commercial concrete waste autoclaved aerated concrete according to claim 1, characterized in that: The steps include: (1) According to the composition and mass percentage of the cementitious materials, weigh 30% to 40% of carbonized steel slag powder, 20% to 30% of carbonized commercial concrete plant solid waste powder, 20% to 30% of cement, 4% to 12% of lime, and 2% to 6% of building gypsum; and weigh 0.1% to 0.5% of water reducing agent and 0.08% to 0.12% of aluminum paste as a percentage of the total mass of the cementitious materials; (2) adding carbonized steel slag powder, carbonized commercial concrete station solid waste powder, cement, lime, and building gypsum into a mixer and stirring for 2 to 5 minutes to obtain a mixed dry powder; (3) controlling the water-to-material mass ratio to be 0.5-0.7, dissolving the water reducing agent and aluminum paste in water, adding the mixed dry powder obtained in step (2), and continuing to stir for 1-3 minutes to obtain a slurry; (4) The slurry obtained in step (3) is cast into shape, and is pre-cured at a temperature of 60 to 70° C. for 5 to 7 hours before demolding, and then placed in an autoclave for autoclaving at a saturated steam pressure of 1 to 2 MPa for 5 to 7 hours to obtain a finished aerated concrete block, i.e., aerated concrete based on carbonized steel slag-commercial mixing station solid waste.

10. The method for preparing carbonized steel slag-commercial concrete waste autoclaved aerated concrete according to claim 9, characterized in that: The performance indicators of the prepared steel slag-commercial concrete solid waste-based aerated concrete are as follows: dry density 670~725kg / m 3 , the compressive strength is not less than 5.4Mpa, the drying shrinkage value does not exceed 0.50mm / m, the average mass loss after freezing is ≤5%, the average strength loss is ≤20%, and the thermal conductivity does not exceed 0.16W / (m·K).

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