Solid waste-based aerated concrete and preparation method and application thereof

Abstract

The present application relates to the technical field of special low-carbon building materials, and particularly relates to a solid waste-based aerated concrete as well as a preparation method and application thereof, which is used for effectively regulating magnesium phase behavior in dolomite and realizing high-value utilization of the dolomite, and is made of the following raw materials in parts by mass: cement 25-35 parts; dolomite powder 50-60 parts; quartz powder 15-20 parts; sodium sulfate 0.2-0.5 parts; magnesium phosphate-silicate composite cementing system 4-10 parts; aluminum source-carbonate composite agent 1-3 parts; steel slag-red mud-fly ash ternary solid waste micro powder 10-18 parts; composite retarder 0.2-0.5 parts; water 33-40 parts; water reducing agent 0.06-0.09 parts; and foaming agent 0.09-0.11 parts. The present application solves the stability problem caused by application of high-magnesium dolomite, solves the cracking risk caused by magnesium expansion, and guarantees the dimensional stability and long-term durability of the product.

Description

Technical Field

[0001] This invention relates to the field of special low-carbon building materials technology, and in particular to a solid waste-based aerated concrete, its preparation method and application. Background Technology

[0002] Autoclaved aerated concrete (AAC), as an important lightweight, thermally insulating, and fire-resistant building material, relies primarily on the high-strength crystalline phases such as hydrated calcium silicate and tobermorite, formed through a hydrothermal reaction between calcareous and siliceous materials under high temperature and pressure. Traditionally, siliceous materials have been derived mainly from high-grade quartz sand or fly ash. However, with the increasing scarcity of high-quality siliceous resources and ever-increasing environmental protection requirements, seeking abundant and inexpensive alternative raw materials has become an urgent need for the sustainable development of the industry.

[0003] dolomite( Dolomite is a widely distributed and abundant carbonate mineral, theoretically a potential raw material for calcium-magnesium composites. However, its application in building materials, especially in autoclaved aerated concrete (AAC), has few successful cases. The fundamental reason lies in the significant technical obstacles posed by the high magnesium content in dolomite. Under alkaline autoclaving conditions, the magnesium ions produced by the decomposition of dolomite tend to form magnesium hydroxide (MgO). The formation of magnesium hydroxide is accompanied by significant volume expansion, and its crystal structure has poor compatibility with the main hydration products of silicate systems, easily forming weak zones at the interface. This leads to a series of fatal defects in the final product, such as poor volume stability, late-stage expansion cracking, and insufficient strength development. Although existing technologies have attempted to partially replace siliceous materials with industrial solid waste, they have generally failed to effectively address the negative effects of magnesium in dolomite. This makes it difficult to achieve high dosing levels of dolomite in aerated concrete, and even more difficult to guarantee the long-term stability of product performance. Therefore, developing an aerated concrete technology that can effectively control the behavior of the magnesium phase in dolomite and achieve its high-value utilization has significant practical significance and application value. Summary of the Invention

[0004] This invention provides a solid waste-based aerated concrete, its preparation method, and its application, which effectively controls the behavior of the magnesium phase in dolomite and realizes its high-value utilization.

[0005] To alleviate the above-mentioned technical problems, the technical solution provided by the present invention is as follows:

[0006] A type of solid waste-based aerated concrete is made from the following raw materials in parts by weight:

[0007] 25-35 parts cement;

[0008] 50-60 parts of dolomite powder;

[0009] 15-20 parts of quartz powder;

[0010] Sodium sulfate 0.2–0.5 parts;

[0011] 4-10 parts of magnesium phosphate-silicate composite gelling system;

[0012] 1-3 parts of aluminum source-carbonate composite agent;

[0013] 10-18 parts of ternary solid waste powder consisting of steel slag, red mud, and fly ash;

[0014] 0.2–0.5 parts of composite retarder;

[0015] 33-40 parts water;

[0016] Water-reducing agent 0.06–0.09 parts;

[0017] Foaming agent 0.09 to 0.11 parts.

[0018] Furthermore,

[0019] The magnesium phosphate-silicate composite gelling system consists of component A and component B.

[0020] Component A consists of the following raw materials in parts by weight: 45-55 parts of recalcined activated magnesium oxide, 35-45 parts of ammonium dihydrogen phosphate, 5-8 parts of zinc borate, and 3-5 parts of silica fume.

[0021] Component B consists of the following raw materials in parts by mass: 60 parts of water glass with a modulus of 1.8 to 2.2, 20 parts of nano-metakaolin, 15 parts of calcium hydroxide powder, and 5 parts of sodium gluconate.

[0022] The mass ratio of component A to component B is 3:1.

[0023] Furthermore,

[0024] The aluminum source-carbonate composite agent is composed of aluminum sulfate and sodium carbonate, and the mass ratio of the mixture is aluminum sulfate:sodium carbonate = 1:(0.8~1.2).

[0025] Furthermore,

[0026] In the aforementioned ternary solid waste powder consisting of steel slag, red mud, and fly ash, the ratio of steel slag powder to calcined red mud to Class II fly ash is 5:3:2.

[0027] The specific surface area of ​​the steel slag powder is not less than 480 m² / kg;

[0028] The calcined red mud is red mud that has been calcined at 550℃ for 2 hours.

[0029] The residue on a 45μm square-hole sieve for the Class II fly ash is no more than 15%.

[0030] Furthermore,

[0031] The composite retarder is composed of sodium tetraborate, tartaric acid and calcium dihydrogen phosphate, with a mass ratio of sodium tetraborate: tartaric acid: calcium dihydrogen phosphate = (2-3): (1-1.5): 1.

[0032] Furthermore,

[0033] The dolomite powder The mass content is 65-95%. The mass content is 0-35%. The mass content is 0-10%, the mass content of clay minerals is 0-10%, and the residue on an 80μm square hole sieve is 5-15%.

[0034] Furthermore,

[0035] The cement is ordinary Portland cement with a strength grade of not less than 42.5;

[0036] The water-reducing agent is a polycarboxylate-based high-efficiency water-reducing agent with a water reduction rate of 35-45%.

[0037] The foaming agent is a protein-based physical foaming agent.

[0038] A method for preparing the above-mentioned solid waste-based aerated concrete includes the following steps:

[0039] S1. Raw material pretreatment: Dolomite powder is mixed with an aqueous solution of aluminum source-carbonate composite agent and dried to obtain pretreated dolomite powder; steel slag-red mud-fly ash ternary solid waste micro powder is mixed with part of water and part of sodium sulfate for prehydration to obtain prehydrated slurry; components A and B of magnesium phosphate-silicate composite cementitious system are mixed with water respectively, and then mixed in proportion for later use.

[0040] S2. Gradient mixing: First, dry mix cement, pretreated dolomite powder and quartz powder at low speed; then add the prehydrated slurry and magnesium phosphate-silicate composite slurry and mix at medium speed; then homogenize by high-speed shear vacuum mixing; finally add composite retarder, residual sodium sulfate, water-reducing agent and foaming agent and mix at medium and low speed to obtain the finished slurry.

[0041] S3. Pouring and Static Curing: The finished slurry is poured into the mold and statically cured for 3-4 hours at 45-55℃ and relative humidity not less than 80%. After demolding, the aerated concrete blank is obtained.

[0042] S4. Autoclaving: The aerated concrete billet is subjected to autoclaving, which includes sequential steps of vacuuming, heating, constant temperature insulation and cooling.

[0043] The specific steps of heating and holding at a constant temperature are as follows: First, heat the temperature to 120-130℃ at a rate of 0.8-1.2℃ / min and hold for 120-150 minutes; then heat the temperature to 150℃ at a rate of 0.5℃ / min and hold for 90 minutes; then heat the temperature to 170-180℃ at a rate of 0.5-1.0℃ / min and hold for 60-90 minutes.

[0044] After curing, cool the temperature to 100-120℃ at a rate of 0.2-0.3℃ / min, and then... Micro-pressure carbonization treatment yields the solid waste-based aerated concrete product.

[0045] Furthermore,

[0046] The steps described in step S4 The conditions for micro-pressure carbonization treatment are:

[0047] Under a pressure of 0.2–0.5 MPa, a volume concentration of 5–15% was introduced into the curing vessel. The gas is processed over a period of 30 to 60 minutes.

[0048] An application of solid waste-based aerated concrete as described above.

[0049] The technical effects are analyzed as follows:

[0050] In the initial stage of curing, the magnesium phosphate-silicate composite cementing system allows its magnesium phosphate component (component A) to rapidly react with the dolomite and release its binder. The reaction produces high-strength magnesium ammonium phosphate (struvite) crystals. This pathway prioritizes the formation of magnesium hydroxide, thus consuming a large amount of free magnesium ions at the source and converting them into a beneficial reinforcing phase. Simultaneously, the silicate activator (component B) in the system promotes the formation of stable hydrated magnesium silicate (MSH) gel in the later stages, rather than expanding magnesium hydroxide, by adjusting the pH of the slurry liquid phase and providing an active silicon source.

[0051] By adding an aluminum source-carbonate composite agent, conditions were created for the formation of layered double hydroxides (LDHs) on the surface of dolomite particles and in the liquid phase of the slurry. Under the specific temperature, pressure, and alkaline environment of autoclaving, the aluminum source provides... Dolomite provided And carbonates provide Plasma can react in situ at the interface to generate hydroxides with a layered structure. This LDH layer physically barriers the excessive and rapid decomposition of dolomite, controlling the release rate of magnesium ions. On the other hand, its layered structure has ion exchange capacity, which can further fix free magnesium ions, significantly enhancing the interfacial bonding and transition zone density between dolomite particles and cement paste, fundamentally improving the problem of weak interfaces caused by magnesium phase enrichment.

[0052] The addition of ternary solid waste micropowder composed of steel slag, red mud, and fly ash achieves synergistic effects across multiple functions. Firstly, steel slag and calcined red mud provide abundant... , , The alkalinity and active ions in fly ash, together with sodium sulfate, create and maintain a specific alkaline environment that favors silicate reactions but inhibits the large-scale precipitation of magnesium hydroxide. Secondly, the activity of fly ash... and It participates in the later secondary hydration reaction, generating more low-alkalinity CSH and CASH gels, filling pores and optimizing the microstructure of the matrix. Finally, the iron and aluminum components in steel slag and red mud can also react with magnesium ions to form stable mineral phases such as spinel, providing a supplementary pathway for the consumption of magnesium ions.

[0053] In the composite retarder (composed of sodium tetraborate, tartaric acid, and calcium dihydrogen phosphate), the borate and organic acids can form complexes with calcium ions and hydroxyl groups, temporarily delaying the early hydration of cement and the initial decomposition of dolomite. Calcium dihydrogen phosphate, on the other hand, can provide phosphate ions later, assisting the reaction of the magnesium phosphate system. This composite retarding effect ensures that the release rate of magnesium ions matches the reaction rate of each of the aforementioned consumption pathways, avoiding the uncontrolled formation of magnesium hydroxide in the early stages of the reaction due to excessively high local magnesium ion concentrations.

[0054] The relatively mild curing conditions in the first stage prioritized the magnesium phosphate reaction and the full construction of the interfacial LDH layer, completing the initial fixation of the magnesium phase. The increased temperature in the second stage deeply stimulated the silicate reaction and the activity of the solid waste powder, promoting the large-scale formation of high-strength crystalline phases such as tobermorite and hydrated magnesium silicate. Finally... Micro-pressure carbonization can convert any trace amounts of magnesium hydroxide that may remain after curing into dense and stable magnesium carbonate (magnesite).

[0055] Through the aforementioned synergistic technical mechanism, the solid waste-based aerated concrete prepared by this invention achieves the following outstanding technical effects:

[0056] It solves the stability problem brought about by the application of high-magnesium dolomite, eliminates the risk of cracking caused by magnesium expansion, and ensures the dimensional stability and long-term durability of the products.

[0057] While achieving high volume stability, mechanical strength is significantly improved.

[0058] This method achieves high-volume, synergistic utilization of dolomite powder with various industrial solid wastes such as steel slag, red mud, and fly ash. The high total solid waste content significantly reduces reliance on natural resources like high-quality quartz sand, resulting in a substantial decrease in raw material costs. Simultaneously, the optimized maintenance system reduces energy consumption. The carbonization process also has a carbon sequestration function, making it highly environmentally friendly. Detailed Implementation

[0059] Dry density test (GB / T 11969-2020 "Test Methods for Performance of Autoclaved Aerated Concrete")

[0060] Compressive strength testing GB / T 11971-1997 "Test Methods for Mechanical Properties of Aerated Concrete"

[0061] Drying shrinkage test GBT11972-1997 - Test method for drying shrinkage of aerated concrete

[0062] Freeze-thaw resistance test GB / T 11973-1997 "Test Method for Freeze-Thaw Resistance of Aerated Concrete"

[0063] Example 1

[0064] This embodiment provides a solid waste-based aerated concrete, the raw materials of which include, by weight, the following: 30 parts cement, 55 parts dolomite powder, 18 parts quartz powder, 0.3 parts sodium sulfate, 7 parts magnesium phosphate-silicate composite cementitious system (component A), 2 parts aluminum source-carbonate composite agent (component B), 15 parts steel slag-red mud-fly ash ternary solid waste micro powder (component C), 0.35 parts composite retarder (component D), 36 parts water, 0.075 parts water-reducing agent, and 0.1 parts foaming agent.

[0065] First, the raw materials are pretreated: Dolomite powder is mixed evenly with an aqueous solution of component B and then dried to obtain pretreated dolomite powder; component C is mixed with some water and some sodium sulfate and pre-hydrated for 2 hours to obtain a pre-hydrated slurry; components A and B of component A are mixed separately with water and then mixed in proportion for later use. Gradient mixing is then performed: cement, pretreated dolomite powder, and quartz powder are added to a mixer and dry-mixed at low speed for 3 minutes; the pre-hydrated slurry and component A slurry are added, and the mixing speed is increased to medium speed for 5 minutes; then, the mixture is homogenized in a high-speed shear vacuum mixer for 8 minutes; finally, component D, the remaining sodium sulfate, water-reducing agent, and foaming agent are added, and the mixture is mixed at medium-low speed for 3 minutes to obtain a homogeneous finished slurry. The slurry is poured into a mold and allowed to stand for 3.5 hours at 50℃ and 85% relative humidity to harden, then demolded to obtain an aerated concrete blank. The green body underwent autoclaving treatment: first, a vacuum was applied, then the temperature was increased to 125℃ at 1.0℃ / min and held for 135 minutes, followed by an increase to 150℃ at 0.5℃ / min and held for 90 minutes, and then increased to 175℃ at 0.8℃ / min and held for 75 minutes; after curing, the temperature was decreased to 110℃ at 0.25℃ / min, and a 10% volume concentration of [unspecified substance] was introduced under a pressure of 0.3MPa. The gas is carbonized for 45 minutes to finally produce solid waste-based aerated concrete.

[0066] The finished product underwent performance testing, revealing a dry density of 625 kg / m³, a compressive strength of 6.8 MPa, a drying shrinkage of 0.38 mm / m, and a mass loss rate of 3.2% after a freeze-thaw test. These results indicate that component A effectively consumed the substances released by the dolomite. Component A inhibited the expansion and formation of magnesium hydroxide; component B promoted the formation of the LDH layer structure and enhanced interfacial adhesion; component C regulated the alkaline environment and participated in the secondary hydration reaction; and component D coordinated the early reaction process. The synergistic effect of these four components enabled the high utilization of high-magnesium dolomite, resulting in excellent mechanical properties, volume stability, and durability of the finished product.

[0067] Example 2

[0068] This embodiment provides another type of solid waste-based aerated concrete, the raw materials of which include, by mass parts: 28 parts cement, 58 parts dolomite powder, 16 parts quartz powder, 0.4 parts sodium sulfate, 5 parts component A, 1.5 parts component B, 12 parts component C, 0.25 parts component D, 38 parts water, 0.08 parts water-reducing agent, and 0.095 parts foaming agent.

[0069] The preparation process is basically the same as in Example 1, except that the static curing time is adjusted to 3 hours, the heating rate of the first stage of autoclaving is adjusted to 0.9℃ / min, and the constant temperature time is adjusted to 120 minutes.

[0070] The finished product performance test results were as follows: dry density 610 kg / m³, compressive strength 6.2 MPa, drying shrinkage 0.41 mm / m, and mass loss rate after freezing 3.8%. Although the amount of component A was slightly reduced, the system still effectively controlled the release and conversion of magnesium ions through the synergistic effect of components B, C, and D. The product had good overall performance, further verifying the applicability and process adaptability of the formulation of this invention.

[0071] Comparative Example 1

[0072] Raw material composition: Except for the absence of magnesium phosphate-silicate composite gelling system (component A), the types and amounts of other raw materials in this comparative example are the same as those in Example 1.

[0073] Since component A is absent, premixing of component A is unnecessary in the pretreatment step. In the gradient mixing step, medium-speed mixing is performed directly after adding the prehydrated slurry, without adding component A slurry. The remaining steps are the same as in Example 1.

[0074] Test results showed that the finished product had a dry density of 640 kg / m³, a compressive strength of 4.5 MPa, a drying shrinkage of 0.62 mm / m, and a mass loss rate of 7.5% after freezing. Compared with Example 1, the compressive strength decreased by approximately 33.8%, the drying shrinkage was significantly increased, and the freeze resistance was significantly deteriorated. This indicates that the absence of component A led to... The magnesium hydroxide was not effectively converted into magnesium ammonium phosphate crystals, which increased the amount of magnesium hydroxide generated in the system, causing volume expansion and weak interfaces, and seriously affecting the mechanical properties and long-term stability of the product.

[0075] Comparative Example 2

[0076] This comparative example is identical to Example 1 except that it does not contain aluminum source-carbonate composite agent (component B).

[0077] In the raw material pretreatment, the dolomite powder is not mixed with the aqueous solution of component B; the raw dolomite powder is used directly. In the gradient mixing step, the dry-mixed raw materials are only cement, raw dolomite powder, and quartz powder. The remaining process steps are the same as in Example 1.

[0078] Test results showed that the finished product had a dry density of 630 kg / m³, a compressive strength of 5.1 MPa, a drying shrinkage of 0.55 mm / m, and a mass loss rate of 6.3% after freezing. The results indicate that the lack of component B prevented the formation of an LDH barrier structure on the dolomite surface, accelerated the release rate of magnesium ions, and decreased the density of the interfacial transition zone. Therefore, although the product possessed a certain strength, its volume stability and freeze-thaw durability were significantly lower than those of Example 1.

[0079] Comparative Example 3

[0080] Except for the absence of steel slag-red mud-fly ash ternary solid waste powder (component C) in this comparative example, the other raw materials are the same as in Example 1.

[0081] There is no pre-hydration step in the raw material pretreatment. During gradient mixing, component A slurry is added directly after dry mixing, without adding pre-hydrated slurry. The remaining steps are the same as in Example 1.

[0082] Test results showed that the finished product had a dry density of 660 kg / m³, a compressive strength of 5.3 MPa, a drying shrinkage of 0.58 mm / m, and a mass loss rate of 6.8% after freezing. The absence of component C weakened the system's ability to regulate the alkaline environment, resulted in insufficient active silicon-aluminum source, incomplete secondary hydration reaction, and high microstructure porosity. Therefore, the product exhibited higher density, lower strength, and decreased durability, indicating that component C plays a crucial role in optimizing the reaction environment and enhancing the matrix structure.

[0083] Comparative Example 4

[0084] Raw material composition: Except for the absence of composite retarder (component D), the raw materials in this comparative example are the same as those in Example 1.

[0085] In the final stage of gradient stirring, only the remaining sodium sulfate, water-reducing agent, and foaming agent are added; component D is not added. The remaining process conditions are the same as in Example 1.

[0086] Performance testing and correlation analysis: The finished product had a dry density of 635 kg / m³, a compressive strength of 5.8 MPa, a drying shrinkage of 0.49 mm / m, and a mass loss rate of 5.2% after freezing. Although the mechanical properties were relatively similar to those of Example 1, the drying shrinkage was still significantly higher, and the freeze resistance was also reduced. This indicates that the slow-release regulation effect of component D has a positive effect on coordinating the matching of magnesium ion release and consumption reactions, which helps to improve the volume stability and durability of the product.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A solid waste-based aerated concrete, characterized in that, Made from the following parts by weight of raw materials: 25-35 parts cement; 50-60 parts of dolomite powder; 15-20 parts of quartz powder; Sodium sulfate 0.2–0.5 parts; 4-10 parts of magnesium phosphate-silicate composite gelling system; 1-3 parts of aluminum source-carbonate composite agent; 10-18 parts of ternary solid waste powder consisting of steel slag, red mud, and fly ash; 0.2–0.5 parts of composite retarder; 33-40 parts water; Water-reducing agent: 0.06–0.09 parts; Foaming agent 0.09 to 0.11 parts.

2. The solid waste-based aerated concrete according to claim 1, characterized in that, The magnesium phosphate-silicate composite gelling system consists of component A and component B. Component A consists of the following raw materials in parts by weight: 45-55 parts of recalcined activated magnesium oxide, 35-45 parts of ammonium dihydrogen phosphate, 5-8 parts of zinc borate, and 3-5 parts of silica fume. Component B consists of the following raw materials in parts by mass: 60 parts of water glass with a modulus of 1.8 to 2.2, 20 parts of nano-metakaolin, 15 parts of calcium hydroxide powder, and 5 parts of sodium gluconate. The mass ratio of component A to component B is 3:

1.

3. The solid waste-based aerated concrete according to claim 1, characterized in that, The aluminum source-carbonate composite agent is composed of aluminum sulfate and sodium carbonate, and the mass ratio of the mixture is aluminum sulfate: sodium carbonate = 1: (0.8~1.2).

4. The solid waste-based aerated concrete according to claim 1, characterized in that, In the aforementioned ternary solid waste powder consisting of steel slag, red mud, and fly ash, the ratio of steel slag powder to calcined red mud to Class II fly ash is 5:3:

2. The specific surface area of ​​the steel slag powder is not less than 480 m² / kg; The calcined red mud is red mud that has been calcined at 550℃ for 2 hours. The residue on a 45μm square-hole sieve for the Class II fly ash is no more than 15%.

5. The solid waste-based aerated concrete according to claim 1, characterized in that, The composite retarder is composed of sodium tetraborate, tartaric acid and calcium dihydrogen phosphate, with a mass ratio of sodium tetraborate: tartaric acid: calcium dihydrogen phosphate = (2-3): (1-1.5):

1.

6. The solid waste-based aerated concrete according to claim 1, characterized in that, The dolomite powder The mass content is 65-95%. The mass content is 0-35%. The mass content is 0-10%, the mass content of clay minerals is 0-10%, and the residue on an 80μm square hole sieve is 5-15%.

7. The solid waste-based aerated concrete according to claim 1, characterized in that, The cement is ordinary Portland cement with a strength grade of not less than 42.5; The water-reducing agent is a polycarboxylate-based high-efficiency water-reducing agent with a water reduction rate of 35-45%. The foaming agent is a protein-based physical foaming agent.

8. A method for preparing solid waste-based aerated concrete as described in any one of claims 1 to 7, characterized in that, Includes the following steps: S1. Raw material pretreatment: Dolomite powder is mixed with an aqueous solution of aluminum source-carbonate composite agent and dried to obtain pretreated dolomite powder; steel slag-red mud-fly ash ternary solid waste micro powder is mixed with part of water and part of sodium sulfate for prehydration to obtain prehydrated slurry; components A and B of magnesium phosphate-silicate composite cementitious system are mixed with water respectively, and then mixed in proportion for later use. S2. Gradient mixing: First, dry mix cement, pretreated dolomite powder and quartz powder at low speed; then add the prehydrated slurry and magnesium phosphate-silicate composite slurry and mix at medium speed; then homogenize by high-speed shear vacuum mixing; finally add composite retarder, residual sodium sulfate, water-reducing agent and foaming agent and mix at medium and low speed to obtain the finished slurry. S3. Pouring and Static Curing: The finished slurry is poured into the mold and statically cured for 3-4 hours at 45-55℃ and relative humidity not less than 80%. After demolding, the aerated concrete blank is obtained. S4. Autoclaving: The aerated concrete billet is subjected to autoclaving, which includes sequential steps of vacuuming, heating, constant temperature insulation and cooling. The specific steps of heating and holding at a constant temperature are as follows: First, heat the temperature to 120-130℃ at a rate of 0.8-1.2℃ / min and hold for 120-150 minutes; then heat the temperature to 150℃ at a rate of 0.5℃ / min and hold for 90 minutes; then heat the temperature to 170-180℃ at a rate of 0.5-1.0℃ / min and hold for 60-90 minutes. After curing, cool the temperature to 100-120℃ at a rate of 0.2-0.3℃ / min, and then... Micro-pressure carbonization treatment yields the solid waste-based aerated concrete product.

9. The preparation method according to claim 8, characterized in that, The steps described in step S4 The conditions for micro-pressure carbonization treatment are: Under a pressure of 0.2–0.5 MPa, a volume concentration of 5–15% was introduced into the curing vessel. The gas is processed over a period of 30 to 60 minutes.

10. An application of solid waste-based aerated concrete as described in any one of claims 1 to 7.