Alkali-activated full-solid waste foam concrete hollow self-insulation brick and preparation method thereof

Abstract

The invention discloses an alkali-activated all-solid waste foam concrete hollow self-insulation brick which is composed of a cementing material, a filling material, an alkali activator, H2O2, a physical foaming agent and a polycarboxylic acid water reducer. The cementing material is prepared from waste incineration fly ash, fly ash, coal gangue, red mud, mackerel bone powder and silica gel desiccant powder; the filling material is composed of polystyrene foam and hair fibers. The cementing material, the filling material and the physical foaming agent mother liquor used in the invention are all prepared from solid wastes, so that the production cost and the carbon emission of the self-insulation brick are greatly reduced. Meanwhile, the mechanical property and the heat preservation property of the self-heat-preservation brick are improved by utilizing an alkali excitation technology, common ball milling treatment and a mode of combining physical foaming and chemical foaming. According to the embodiment with the best comprehensive performance, the compressive strength reaches 49.41% of that of a pure cement control example, the thermal insulation performance is improved by 52.63% compared with that of the pure cement control example, the drying shrinkage value is 0.34 mm / m, the fire resistance rating is A1, and the requirements for strength, thermal insulation, durability and fire prevention of the self-thermal-insulation brick are well met.

Description

Technical Field

[0001] The present invention belongs to the field of resource utilization of solid waste, and particularly relates to a new type of all-solid waste self-insulating wall material and a preparation method thereof. Background Art

[0002] With the increasingly serious problems of global warming and resource shortage, sustainable development has become the focus of global attention. As one of the main sources of energy consumption and carbon emissions, the green transformation of the construction industry is imperative. Preparing lightweight self-insulating materials from solid waste can not only significantly reduce carbon emissions in the construction industry, relieve resource pressure, but also reduce energy consumption and promote the harmonious development of buildings and the environment.

[0003] Waste incineration, as an efficient treatment method with significant volume reduction effect, has been widely used. However, the fly ash generated by waste incineration brings new environmental challenges. The composition of waste incineration fly ash is complex, containing persistent organic pollutants such as dioxins and furans, as well as heavy metal salts, belonging to HW18 hazardous waste. If not properly treated, it will pose a serious threat to the ecological environment and human health. Therefore, how to safely and effectively treat waste incineration fly ash has become an urgent problem to be solved. Fly ash is the main solid waste discharged from coal-fired power plants. If not properly treated, its dust will pollute the atmosphere, and discharging it into water systems may cause river siltation. The toxic chemicals contained in it will also harm the ecological system and human health. Coal gangue is the main solid waste generated during coal mining and washing. The accumulation of coal gangue not only occupies a large amount of land resources, but also poses a serious threat to the ecological environment. However, coal gangue is rich in aluminosilicates (such as Al 2 O 3 、SiO 2 etc.), and has the potential to be used as a raw material for alkali-activated cementitious materials. Due to its low calcium content, its activation performance is poor, but its alkali activation performance can be significantly improved by adding an appropriate amount of calcium source. Red mud is a solid waste generated during the extraction of alumina in the aluminum industry, and its main components include Al 2 O 3 、Fe 2 O 3 etc. Red mud has the characteristic of high alkalinity, and alkaline substances are easily leached out by rainwater scouring, damaging the surrounding soil and water environment. In recent years, with the change of diet structure and the popularization of imported food, the consumption of seafood and packaged food in China has increased significantly. As kitchen waste, mackerel bones are rich in elements such as Ca and Fe. The main component of waste silica gel desiccant is SiO 2 and its chemical properties are stable. Treating mackerel bones and waste silica gel desiccant can be used as a stable Ca source and Si source for cementitious materials, with high reuse value.

[0004] Waste polystyrene foam is difficult to degrade in the natural environment and usually takes hundreds of years or even longer to completely decompose. How to effectively deal with it has become an urgent problem to be solved. Polystyrene foam has the characteristics of light weight and low thermal conductivity, and is suitable for the production of lightweight self-insulating materials. Hair fiber is a common waste in daily life. Its diameter is usually between 10-100μm, and it has certain toughness and tensile strength, and can be used as a reinforcing fiber for cementitious materials. At the same time, the protein content in hair is as high as 90% of the dry weight, showing significant potential for reuse. Summary of the Invention

[0005] Technical problems to be solved: This application mainly proposes an alkali-activated all-solid waste foam concrete hollow self-insulating brick and its preparation method, which solves the technical problems in the prior art that solid waste causes harm to the human body and the environment and occupies land. The cementitious materials used in this application are all composed of solid waste, and an insulating wall material is prepared by the alkali-activation method, providing a low-carbon, environmentally friendly and economical method for preparing self-insulating wall materials from solid waste. The prepared all-solid waste hollow self-insulating brick has excellent mechanical properties and self-insulating and heat-insulating properties.

[0006] The present invention provides an alkali-activated all-solid waste foam concrete hollow self-insulating brick, and the raw materials of the alkali-activated all-solid waste foam concrete hollow self-insulating brick are proportioned by mass as follows:

[0007] Cementitious materials: 45-55 parts of waste incineration fly ash, 10-20 parts of fly ash, 6-16 parts of coal gangue, 6-16 parts of red mud, 4-8 parts of mackerel bone powder, 5-9 parts of silica gel desiccant powder;

[0008] Filling materials: 1-3 parts of polystyrene foam, 2-4 parts of hair fiber;

[0009] Alkali activator: Na 2 SiO 3 solution 6-15.7 parts, solid NaOH 0.9-3.7 parts, water 31.6-36.9 parts;

[0010] Chemical foaming agent: H 2 O 2 2-4 parts;

[0011] Physical foaming agent: 2.1-3.4 parts of physical foaming agent mother liquor, 0.8-1.4 parts of sodium lauryl sulfate, 0.1-0.2 parts of calcium stearate;

[0012] Additive: 1-1.5 parts of liquid polycarboxylate water reducer.

[0013] The gelling material is pretreated and then ground to obtain a mixed powder. Then, the filling material is mixed with the mixed powder to obtain a mixture. Next, the remaining components are used to chemically foam and physically foam the mixture in sequence, and then it is put into a mold for autoclave forming. The prepared thermal insulation brick has a Ca / Si molar ratio of 0.62 - 1.56, a heat transfer coefficient (W / (m·K)) of 0.16 - 0.30, a strength (MPa) of 3.58 - 5.21, a dry shrinkage value (mm / m) of 0.31 - 0.35, and a fire resistance rating of A1.

[0014] As a preferred technical solution of the present invention: the content of CaO in the waste incineration fly ash is ≥35%, and the Mohs hardness is 2 - 3; the content of SiO 2 in the fly ash is ≥35%, the content of Al 2 O 3 is ≥20%, and the Mohs hardness is 2 - 3; the content of SiO 2 in the coal gangue is ≥50%, the content of Al 2 O 3 is ≥40%, and the Mohs hardness is 5 - 6; the content of CaO in the red mud is ≥15%, the content of Al 2 O 3 is ≥25%, the content of Fe 2 O 3 is ≥20%, the content of Na 2 O is ≥10%, and the Mohs hardness is 4 - 5; the content of CaO in the mackerel bone powder is ≥60%, the content of Fe 2 O 3 is ≥20%, and the Mohs hardness is 2 - 3; the content of SiO 2 in the silica gel desiccant powder is ≥98%, and the Mohs hardness is 6 - 7; the particle size of the polystyrene foam is 3 - 5 mm.

[0015] As a preferred technical solution of the present invention: the waste incineration fly ash needs to go through a pretreatment process of one - time drying, crushing, screening, alkali washing, suction filtration, water washing, suction filtration and secondary drying. The specific pretreatment process of the waste incineration fly ash is as follows:

[0016] Step 1: Place the waste incineration fly ash in an oven and dry it at 105 - 120 °C for 24 - 48 h until the moisture content of the waste incineration fly ash ≤0.5%;

[0017] Step 2: Place the waste incineration fly ash after one - time drying in a high - speed crusher at 30000 - 40000 rpm / min and crush it for 1 - 2 min;

[0018] Step 3: Screen the crushed waste incineration fly ash through a 150 - μm square - hole sieve, and collect the waste incineration fly ash with a particle size less than 150 μm under the sieve for subsequent use;

[0019] Step 4: Mix the incineration fly ash with a particle size less than 150 μm after screening and 40% NaOH solution in a mass ratio of NaOH solution: incineration fly ash = 10:1 for alkali washing, and then use magnetic stirring to promote the alkali washing process. The stirring rate is 20 - 30 rpm, and the stirring time is 30 - 60 min;

[0020] Step 5: Let the mixed solution of the alkali-washed NaOH solution + incineration fly ash stand for 1 - 2 h;

[0021] Step 6: Use a suction filter to separate the solid-liquid of the mixed solution of the standing NaOH solution + incineration fly ash to obtain the incineration fly ash solid. The filter membrane used for suction filtration is a 0.45 μm filter membrane;

[0022] Step 7: Mix the incineration fly ash obtained by suction filtration and clear water in a mass ratio of clear water: incineration fly ash = 10:1 for water washing, and then use magnetic stirring to promote the water washing process. The stirring rate is 20 - 30 rpm, and the stirring time is 30 - 60 min;

[0023] Step 8: Let the suspension solution of the water-washed incineration fly ash stand for 1 - 2 h;

[0024] Step 9: Use a suction filter to separate the solid-liquid of the standing suspension solution of the incineration fly ash to obtain the incineration fly ash solid. The filter membrane used for suction filtration is a 0.45 μm filter membrane;

[0025] Step 10: Place the incineration fly ash obtained by suction filtration in an oven and dry it at 105 - 120 °C for 24 - 48 h until the water content of the incineration fly ash ≤ 0.5%.

[0026] As a preferred technical solution of the present invention: The fly ash and coal gangue are dried in an oven at 105 - 120 °C for 24 - 48 h, and the water content ≤ 0.5%.

[0027] As a preferred technical solution of the present invention: The red mud needs to undergo a pretreatment process of one-time drying, one-time crushing, secondary drying, secondary crushing, and screening. The specific red mud pretreatment process is as follows:

[0028] Step 1: Place the original wet red mud in an oven and dry it at 105 - 120 °C for 24 - 48 h until the water content of the red mud ≤ 10%;

[0029] Step 2: Place the red mud after one-time drying in a high-speed crusher at 30000 - 40000 rpm / min and crush it for 1 - 2 min;

[0030] Step 3: Place the once-crushed red mud in an oven and dry it at 105 - 120 °C for 24 - 48 h until the water content of the red mud ≤ 0.5%;

[0031] Step 4: Place the red mud after secondary drying in a high-speed crusher at 30000 - 40000 rpm and crush it for 1 - 2 min;

[0032] Step 5: Screen the red mud after secondary crushing through a square-hole sieve with a size of 150 μm, and collect the red mud with a particle size less than 150 μm under the sieve for subsequent use.

[0033] As a preferred technical solution of the present invention: The mackerel bone powder is obtained through a pre-treatment process of primary cleaning, cooking, secondary cleaning, soaking, drying, pulverizing, heating, and screening of mackerel bones. The specific pre-treatment process of the mackerel bones is as follows:

[0034] Step 1: After washing the mackerel bones once with clean water, place them in an induction cooker and cook at 90 - 100 °C for 30 - 45 min;

[0035] Step 2: Wash the cooked mackerel bones twice with clean water to remove the remaining meat attached to the bones;

[0036] Step 3: Soak the mackerel bones after secondary cleaning in a 0.5% NaOH solution for 2 - 3 h, drain them, and then soak them in a 25% acetone solution for 7 - 8 h;

[0037] Step 4: Place the mackerel bones after solution soaking in an oven and dry them at 105 - 120 °C for 24 - 48 h;

[0038] Step 5: Place the dried mackerel bones in a high-speed crusher at 30000 - 40000 rpm and crush them for 1 - 2 min;

[0039] Step 6: Place the crushed mackerel bone powder in a heating furnace at 700 - 800 °C and heat it for 2 - 3 h;

[0040] Step 7: Screen the heated mackerel bone powder through a square-hole sieve with a size of 150 μm, and collect the mackerel bone powder with a particle size less than 150 μm under the sieve.

[0041] As a preferred technical solution of the present invention: The silica gel desiccant powder is prepared from waste silica gel desiccants. The specific preparation process of the silica gel desiccant powder is as follows:

[0042] Step 1: Use the cold air gear of a hair dryer to blow and wash the waste silica gel desiccant for 4 - 5 min to remove the dust on the surface;

[0043] Step 2: Place the purged silica gel desiccant in an oven and dry it at 105 - 120 °C for 24 - 48 h;

[0044] Step 3: Place the dried silica gel desiccant in a high-speed crusher at 30000 - 40000 rpm and crush it for 1 - 2 min;

[0045] Step 4: Screen the silica gel desiccant powder obtained after crushing through a 150 μm square-hole sieve, and collect the silica gel desiccant powder with a particle size less than 150 μm under the sieve.

[0046] As a preferred technical solution of the present invention: The foam concrete adopts a foaming method that combines physical foaming and chemical foaming. The chemical foaming agent is 30% H 2 O 2 , and the Fe 2 O 3 rich in red mud and mackerel bone powder can replace traditional MnO 2 , and promote the decomposition of H 2 O 2 .

[0047] As a preferred technical solution of the present invention: On the one hand, the hair fiber serves as a cementitious material reinforcing fiber with a length of 20 - 30 mm. On the other hand, it serves as a raw material for preparing the physical foaming agent mother liquor. The specific process for preparing the foaming agent mother liquor is as follows:

[0048] Step 1: Rinse the hair fiber with clean water, drain it, and place it in an oven to dry at 45 - 60 °C for 24 - 48 h;

[0049] Step 2: Mix the dried hair fiber according to the mass ratio of hair fiber: deionized water = 1:8, add 30% H 2 O 2 solution, and then add 30% NaOH solution to adjust the pH to 9 - 12;

[0050] Step 3: Heat the above hair fiber mixed solution in a constant temperature water bath at 90 - 100 °C, and the hydrolysis time is 3 - 4 h;

[0051] Step 4: Cool the heated and hydrolyzed hair fiber mixed solution to room temperature and let it stand for 1 - 2 h;

[0052] Step 5: Filter the static hair fiber mixed solution with a qualitative filter paper with a pore size of 10 - 12 μm to obtain a clear solution;

[0053] Step 6: Adjust the pH of the clear solution to 7 - 8 with 30% acetic acid solution under stirring.

[0054] Step 7: Filter the clarified liquid after pH adjustment through qualitative filter paper with a pore size of 10 - 12 μm for the second time, and concentrate it to 5.0 g / L.

[0055] As a preferred technical solution of the present invention: The raw materials of the physical foaming agent are used in the following mass ratio: physical foaming agent mother liquor: sodium lauryl sulfate: calcium stearate = 5:2:0.3, and the concentration of sodium lauryl sulfate is 2 g / L.

[0056] As a preferred technical solution of the present invention: The alkali activator consists of Na 2 SiO 3 solution and solid NaOH. The modulus Ms of the Na 2 SiO 3 solution is 3.0 - 3.6, and the purity of solid NaOH is ≥98%. It is used to reduce the modulus of the Na 2 SiO 3 solution.

[0057] As a preferred technical solution of the present invention: The cementitious material is co-ground by a planetary ball mill for uniform mixing and modification. Weigh the municipal solid waste incineration fly ash, fly ash, coal gangue, red mud, mackerel bone powder and silica gel desiccant powder according to the mass ratio and put them into the planetary ball mill. Grind them at a speed of 300 rpm for 10 - 30 min to obtain a mixed powder with a content ≥98%.

[0058] As a preferred technical solution of the present invention: For the alkali-activated all-solid waste hollow self-insulating brick, one side is provided with a groove, and the other side is provided with a protrusion. The maximum width of the groove and the protrusion part is 40 - 45% of the width of the self-insulating brick. The included angle between the inclined plane of the groove and the protrusion part and the side surface of the self-insulating brick is 70 - 80°. The groove and the protrusion fit together to improve the overall stability of the wall.

[0059] As a preferred technical solution of the present invention: For the alkali-activated all-solid waste hollow self-insulating brick, the hollow structure is composed of large cylinders and small cylinders. The number of large cylinders is ≥5, and the number of small cylinders is ≥13.

[0060] This application also discloses a preparation method of an alkali-activated all-solid waste foam concrete hollow self-insulating brick, which includes the following steps:

[0061] Step a, pretreatment of municipal solid waste incineration fly ash:

[0062] Step a1: Place the municipal solid waste incineration fly ash in an oven and dry it at 105 - 120 °C for 24 - 48 h until the moisture content of the municipal solid waste incineration fly ash ≤0.5%;

[0063] Step a2: Place the municipal solid waste incineration fly ash after the first drying in a high-speed crusher at 30000 - 40000 rpm / min and crush it for 1 - 2 min;

[0064] Step a3: Screen the incinerated fly ash of garbage after crushing through a square hole sieve with a size of 150 μm, and collect the incinerated fly ash of garbage with a particle size less than 150 μm under the sieve for subsequent use;

[0065] Step a4: Mix the incinerated fly ash of garbage with a particle size less than 150 μm after screening and 40% NaOH solution in a mass ratio of NaOH solution: incinerated fly ash of garbage = 10:1 for mixed alkali washing, and then use magnetic stirring to promote the alkali washing process. The stirring rate is 20 - 30 rpm, and the stirring time is 30 - 60 min, so that the alkali content in the incinerated fly ash of garbage ≤ 5%, and the Cl element content ≤ 2%;

[0066] Step a5: Let the mixed solution of NaOH solution + incinerated fly ash of garbage after alkali washing stand for 1 - 2 h;

[0067] Step a6: Use a suction filter to separate the solid and liquid of the mixed solution of NaOH solution + incinerated fly ash of garbage after standing to obtain the incinerated fly ash solid of garbage. The filter membrane used for suction filtration is a 0.45 μm filter membrane;

[0068] Step a7: Place the incinerated fly ash of garbage obtained by suction filtration in an oven, dry it at 105 - 120 °C for 24 - 48 h until the water content of the incinerated fly ash of garbage ≤ 0.5%, then put it into a sealed bag and place it in a drying dish for standby.

[0069] Step b: Preparation of mackerel bone powder:

[0070] Step b1: Wash the mackerel bones once with clean water, then place them in an induction cooker and cook at 90 - 100 °C for 30 - 45 min;

[0071] Step b2: Wash the cooked mackerel bones twice with clean water to remove the residual meat attached to the bones;

[0072] Step b3: Soak the mackerel bones after the second washing in 0.5% NaOH solution for 2 - 3 h, drain them, and then soak them in 25% acetone solution for 7 - 8 h;

[0073] Step b4: Place the mackerel bones after solution soaking in an oven and dry them at 105 - 120 °C for 24 - 48 h;

[0074] Step b5: Place the dried mackerel bones in a high-speed crusher at 30000 - 40000 rpm and crush them for 1 - 2 min;

[0075] Step b6: Place the crushed mackerel bone powder in a heating furnace at 700 - 800 °C and heat it for 2 - 3 h;

[0076] Step b7: Screen the heated mackerel bone powder through a square hole sieve with a pore size of 150 μm, collect the mackerel bone powder with a particle size less than 150 μm under the sieve, and put it into a sealed bag and place it in a drying dish for later use.

[0077] Step c: Preparation of silica gel desiccant powder:

[0078] Step c1: Blow and wash the waste silica gel desiccant with the cold air gear of a hair dryer for 4 - 5 minutes to remove the dust on the surface;

[0079] Step c2: Place the blown and washed silica gel desiccant in an oven and dry it at 105 - 120 °C for 24 - 48 hours;

[0080] Step c3: Place the dried silica gel desiccant in a high-speed crusher at 30000 - 40000 rpm and crush it for 1 - 2 minutes;

[0081] Step c4: Screen the obtained silica gel desiccant powder through a square hole sieve with a pore size of 150 μm, collect the silica gel desiccant powder with a particle size less than 150 μm under the sieve, and put it into a sealed bag and place it in a drying dish for later use.

[0082] Step e: Preparation of physical foaming agent:

[0083] Step e1: Rinse the hair fibers with clean water, drain them and place them in an oven, and dry them at 45 - 60 °C for 24 - 48 hours;

[0084] Step e2: Mix the dried hair fibers according to the mass ratio of hair fibers: deionized water = 1:8, add 30% H 2 O 2 solution, and then add 30% NaOH solution to adjust the pH to 9 - 12;

[0085] Step e3: Heat the above hair fiber mixed solution in a constant temperature water bath at 90 - 100 °C, and the hydrolysis time is 3 - 4 hours;

[0086] Step e4: Cool the heated and hydrolyzed hair fiber mixed solution to room temperature and let it stand for 1 - 2 hours;

[0087] Step e5: Filter the standing hair fiber mixed solution with a qualitative filter paper with a pore size of 10 - 12 μm to obtain a clear solution;

[0088] Step e6: Adjust the pH of the clear solution to 7 - 8 with 30% acetic acid solution under stirring.

[0089] Step e7: Filter the clear solution with a pH adjusted with a qualitative filter paper with a pore size of 10 - 12 μm for the second time and concentrate it to 5.0 g / L.

[0090] Step f: Preparation of hollow self-insulating bricks:

[0091] Step f1. Weigh 45 - 55 parts by mass of waste incineration fly ash, 10 - 20 parts of fly ash, 6 - 16 parts of coal gangue, 6 - 16 parts of red mud, 4 - 8 parts of mackerel bone powder, and 5 - 9 parts of silica gel desiccant powder into a planetary ball mill, and ball mill at a speed of 300 rpm for 10 - 30 min to obtain a mixed powder with a content ≥ 98%;

[0092] Step f2. Add the mixed powder, 1 - 3 parts of polystyrene foam, and 2 - 4 parts of hair fiber into a blender, and slowly stir at a speed of 120 - 150 rpm for 1 - 2 min to uniformly mix the gelling material and the filling material;

[0093] Step f3. Mix 3 - 5 parts of physical foaming agent and water according to the mass ratio of physical foaming agent: water = 1:5, and use a foaming device to control the air pump pressure value at 0.4 - 0.6 Pa to prepare delicate, uniform, and milky white foam;

[0094] Step f4. Mix 40 - 50 parts of alkali activator, 4 parts of H 2 O 2 2, and 1 - 1.5 parts of liquid polycarboxylate water reducer. The modulus and Na 2 O content of the alkali activator are 1.5 - 2.5 and 6 - 10% respectively, and uniformly add them into the blender, and quickly stir at a speed of 300 - 350 rpm for 4 - 6 min to fully foam the H 2 O 2 ;

[0095] Step f5. Uniformly add the foam prepared in step f3 into the slurry obtained in step f4, and slowly stir at a speed of 120 - 150 rpm for 1 - 2 min to obtain a uniform foamed slurry;

[0096] Step f6. Pour the foamed slurry into a hollow self-insulating brick mold, and pre-cure for 12 h in a closed curing environment with a temperature of 20 - 25°C and a relative humidity ≥ 90%;

[0097] Step f7. Remove the mold, send the formed hollow self-insulating bricks into an autoclave, and autoclave for 12 h in an environment with a pressure of 1.2 - 1.5 MPa and a temperature of 180 - 200°C;

[0098] Step f8. Slowly release the pressure in the autoclave, and wait until the temperature drops below 60°C before removing the bricks from the autoclave and demolding to obtain the finished hollow self-insulating bricks.

[0099] The beneficial effects of the present invention are:

[0100] Compared with the prior art, the alkali-activated all-solid waste foam concrete hollow self-insulating brick and its preparation method described in this application have the following technical effects:

[0101] 1. This application uses solid waste such as municipal solid waste incineration fly ash, fly ash, coal gangue, red mud, and mackerel bone powder as cementitious materials, and uses waste polystyrene foam and hair fiber as filling materials. On the one hand, it realizes the production of all-solid waste for building self-insulating materials and effectively harmlessly treats these solid wastes. On the other hand, it greatly reduces the production cost and production carbon emissions of building self-insulating materials.

[0102] 2. Since a large amount of heavy metals are contained in municipal solid waste incineration fly ash, which poses a major hazard to the human body and the environment, in order to achieve the large-scale application of municipal solid waste incineration fly ash, this application conducts pretreatment of alkali washing and water washing of municipal solid waste incineration fly ash with NaOH solution. Among them, the alkali content in municipal solid waste incineration fly ash is reduced by more than 86.5%, the chlorine element content is reduced by more than 95.6%, and the contents of Zn, Pb, and Br elements are reduced by more than 52.4%, 68.6%, and 95.1% respectively, enabling municipal solid waste incineration fly ash to be harmlessly applied to the production of self-insulating bricks.

[0103] 3. Due to the high alkalinity of red mud, this application uses Na 2 O in red mud to replace part of the solid NaOH in the alkali activator. On the basis of the configured alkali activator, the modulus and Na 2 O content of the alkali activator are further adjusted and an alkaline environment is provided for the foaming of H 2 O 2 . At the same time, Fe 2 O 3 in red mud can replace traditional MnO 2 as a catalyst for H 2 O 2 , making full use of the characteristics of the chemical composition of red mud and reducing the production cost of self-insulating bricks.

[0104] 4. A large amount of CaO and Fe 2 O 3 are contained in mackerel bone powder, which can be used as a Ca source to make up for the shortage of Ca content in other solid wastes. At the same time, Fe 2 O 3 can replace traditional MnO 2 as a catalyst for H 2 O 2 , further improving the foaming efficiency of the chemical foaming agent and reducing the production cost of self-insulating bricks.

[0105] 5. The main component of silica gel desiccant powder is SiO 2, having pozzolanic activity, can be used as a Si source to make up for the shortage of Si content in other solid waste. Using silica gel desiccant powder instead of the commonly used nano-SiO in the cementitious material 2 , on the one hand, can reduce the production cost of the self-insulating brick, and on the other hand, avoids the problems of difficult effective dispersion and too long dispersion time of nano-SiO 2 , effectively improving the mechanical properties and production efficiency of the self-insulating brick.

[0106] 6. Hair fibers have certain flexibility and tensile strength, can be used as cementitious material reinforcing fibers to improve the mechanical properties and crack resistance of self-insulating bricks. At the same time, the main component of hair fibers is keratin, which can be used as a raw material for preparing protein-based physical foaming agent mother liquor. Applying hair fibers as solid waste to the preparation of self-insulating bricks can not only act as reinforcing fibers but also be used to prepare protein-based physical foaming agent mother liquor, significantly reducing the production cost of self-insulating bricks.

[0107] 7. This application uses a foaming method that combines physical foaming and chemical foaming. The two foaming methods cooperate with each other to produce a more uniform, fine and stable bubble structure. Physical foaming can quickly form a large number of initial bubbles with larger sizes to provide a basic framework for foamed concrete. Chemical foaming continuously generates smaller bubbles inside the system to further optimize the pore structure, making the foam distribution more uniform and avoiding problems such as large bubble aggregation or bubble collapse, thus significantly improving the thermal insulation performance of the self-insulating brick.

[0108] 8. This application performs co-ball milling treatment on cementitious materials such as waste incineration fly ash, fly ash, coal gangue, red mud and mackerel bone powder. This treatment method can simultaneously modify the particle surface of the materials, increase the intrinsic defects of the material particles, provide more active sites for the hydration reaction, and achieve uniform mixing of each material. Compared with the process of separately ball milling each material first and then mixing in a blender in the traditional process, co-ball milling greatly simplifies the production process. In addition, due to the difference in hardness of each material, co-ball milling can effectively improve the ball milling efficiency by means of the interaction between material particles.

[0109] 9. The self-insulating bricks described in this application have grooves and protrusions on both sides, which can make the blocks fit better during construction and improve the overall stability of the wall. At the same time, the self-insulating brick uses waste polystyrene foam particles as filling materials and has a hollow structure inside. The hollow structure is composed of large cylinders and small cylinders, which can effectively block the heat transfer between indoors and outdoors, help maintain the stability of indoor temperature, and reduce building energy consumption.

[0110] 10. Based on the chemical composition of the solid waste materials, this application designs the proportion of each solid waste material. The Ca / Si molar ratio is 0.62 - 1.56. In the alkaline environment provided by the alkali activator and high-alkalinity red mud, the Ca in each solid waste material2+ 、Al(OH) 4 - and Si(OH) 4 will dissociate and form (N, C)-A-S-H gel through reaction, refining the pore structure. And when the Ca / Si molar ratio is low, more Si(OH) 4 is released from the raw materials, making the material have higher strength and better durability. In this application, the orthogonal design method is adopted, with the proportion of solid waste materials, ball milling time, Na 2 O content of the alkali activator and the modulus of the alkali activator as 4 factors and 3 levels. Among them, the compressive strength of the self-insulating brick with the best comprehensive performance reaches 49.41% of that of pure cement, the heat insulation performance is improved by 52.63% compared with the pure cement control example, the dry shrinkage value is 0.34 mm / m, and the fire resistance rating is A1, which can be well applied to actual projects. Description of the Drawings

[0111] Figure 1 is a three-dimensional model diagram of the alkali-activated all-solid waste foam concrete hollow self-insulating brick of this application.

[0112] Figure 2 is the front view of the alkali-activated all-solid waste foam concrete hollow self-insulating brick of this application.

[0113] Figure 3 is the left view of the alkali-activated all-solid waste foam concrete hollow self-insulating brick of this application.

[0114] Figure 4 is the top view of the alkali-activated all-solid waste foam concrete hollow self-insulating brick of this application.

[0115] Figure 5 is the assembly diagram of the alkali-activated all-solid waste foam concrete hollow self-insulating brick of this application.

[0116] Figure 6 is the preparation flow chart of the alkali-activated all-solid waste foam concrete hollow self-insulating brick of this application. Detailed Embodiments

[0117] The present invention will be further described below through specific embodiments.

[0118] Example 1

[0119] An alkali-activated all-solid waste foam concrete hollow self-insulating brick, the dosage of each component calculated by mass fraction is respectively: 45 parts of waste incineration fly ash, 20 parts of fly ash, 16 parts of coal gangue, 6 parts of red mud, 4 parts of mackerel bone powder, 9 parts of silica gel desiccant powder, 3 parts of polystyrene foam, 2 parts of hair fiber, 3 parts of physical foaming agent, 40 parts of alkali activator (the modulus of the alkali activator and Na 2The O contents are 1.5% and 6% respectively), H 2 O 2 4 parts, 1 part of liquid polycarboxylate water reducer, and the total grinding time of each cementitious material is 10 min.

[0120] Preparation steps:

[0121] Step 1. Weigh 45 parts of waste incineration fly ash, 20 parts of fly ash, 16 parts of coal gangue, 6 parts of red mud, 4 parts of mackerel bone powder, and 9 parts of silica gel desiccant powder according to the mass ratio, and carry out co-grinding through a planetary ball mill to uniformly mix and modify, obtaining a mixed powder with a content ≥ 98%. The ball milling time is 10 min, and the ball milling speed is 300 rpm;

[0122] Step 2. Add the mixed powder, 3 parts of polystyrene foam, and 2 parts of hair fiber into a blender, and slowly stir at a speed of 150 rpm for 2 min to uniformly mix the cementitious material and the filling material;

[0123] Step 3. Mix 3 parts of physical foaming agent and water according to the mass ratio, physical foaming agent: water = 1:5, and use a foaming device. Control the air pump pressure value to be 0.5 Pa to prepare delicate and uniform milky white foam;

[0124] Step 4. Mix 40 parts of alkali activator, H 2 O 2 2 parts, and 1 part of liquid polycarboxylate water reducer. The modulus of the alkali activator and the Na 2 O contents are 1.5 and 6% respectively, and uniformly add them into the blender, and quickly stir at a speed of 350 rpm for 5 min to make the H 2 O 2 fully foam;

[0125] Step 5. Uniformly add the foam prepared in Step 3 into the slurry obtained in Step 4, and slowly stir at a speed of 150 rpm for 2 min to obtain a uniform foamed slurry;

[0126] Step 6. Pour the foamed slurry into a hollow self-insulating brick mold, and pre-cure for 12 h in a closed curing environment with a temperature of 20 - 25 °C and a relative humidity ≥ 90%;

[0127] Step 7. Demold the mold, send the formed hollow self-insulating brick into an autoclave, and autoclave for 12 h in an environment with a pressure of 1.5 MPa and a temperature of 200 °C;

[0128] Step 8. Slowly release the pressure in the autoclave. Wait until the temperature drops below 60 °C before taking out the autoclave and demolding to obtain the finished hollow self-insulating brick.

[0129] Example 2

[0130] An alkali-activated all-solid waste foam concrete hollow self-insulating brick, the dosage of each component calculated by mass fraction is as follows: 45 parts of waste incineration fly ash, 20 parts of fly ash, 16 parts of coal gangue, 6 parts of red mud, 4 parts of mackerel bone powder, 9 parts of silica gel desiccant powder, 3 parts of polystyrene foam, 2 parts of hair fiber, 3 parts of physical foaming agent, 40 parts of alkali activator (the modulus and Na 2 O content of the alkali activator are 2.0 and 8% respectively), H 2 O 2 4 parts, 1 part of liquid polycarboxylate water reducer, and the co-grinding time of each cementitious material is 20 min.

[0131] The preparation method of the hollow self-insulating brick is the same as that of Example 1 in specific steps.

[0132] Example 3

[0133] An alkali-activated all-solid waste foam concrete hollow self-insulating brick, the dosage of each component calculated by mass fraction is as follows: 45 parts of waste incineration fly ash, 20 parts of fly ash, 16 parts of coal gangue, 6 parts of red mud, 4 parts of mackerel bone powder, 9 parts of silica gel desiccant powder, 3 parts of polystyrene foam, 2 parts of hair fiber, 3 parts of physical foaming agent, 40 parts of alkali activator (the modulus and Na 2 O content of the alkali activator are 2.5 and 10% respectively), H 2 O 2 4 parts, 1 part of liquid polycarboxylate water reducer, and the co-grinding time of each cementitious material is 30 min.

[0134] The preparation method of the hollow self-insulating brick is the same as that of Example 1 in specific steps.

[0135] Example 4

[0136] An alkali-activated all-solid waste foam concrete hollow self-insulating brick, the dosage of each component calculated by mass fraction is as follows: 50 parts of waste incineration fly ash, 15 parts of fly ash, 11 parts of coal gangue, 11 parts of red mud, 6 parts of mackerel bone powder, 7 parts of silica gel desiccant powder, 2 parts of polystyrene foam, 3 parts of hair fiber, 4 parts of physical foaming agent, 40 parts of alkali activator (the modulus and Na 2 O content of the alkali activator are 2.5 and 8% respectively), H 2 O 2 3 parts, 1 part of liquid polycarboxylate water reducer, and the co-grinding time of each cementitious material is 10 min.

[0137] The preparation method of the hollow self-insulating brick is the same as that of Example 1 in specific steps.

[0138] Example 5

[0139] An alkali-activated all-solid waste foamed concrete hollow self-insulating brick, the dosages of each component calculated by mass parts are respectively: 50 parts of waste incineration fly ash, 15 parts of fly ash, 11 parts of coal gangue, 11 parts of red mud, 6 parts of mackerel bone powder, 7 parts of silica gel desiccant powder, 2 parts of polystyrene foam, 3 parts of hair fiber, 4 parts of physical foaming agent, 40 parts of alkali activator (the modulus and Na 2 O content of the alkali activator are 1.5 and 10% respectively), H 2 O 2 3 parts, 1 part of liquid polycarboxylate water reducer, and the co-grinding time of each cementitious material is 20 min.

[0140] The preparation method of the hollow self-insulating brick is the same as that of Example 1 in specific steps.

[0141] Example 6

[0142] An alkali-activated all-solid waste foamed concrete hollow self-insulating brick, the dosages of each component calculated by mass parts are respectively: 50 parts of waste incineration fly ash, 15 parts of fly ash, 11 parts of coal gangue, 11 parts of red mud, 6 parts of mackerel bone powder, 7 parts of silica gel desiccant powder, 2 parts of polystyrene foam, 3 parts of hair fiber, 4 parts of physical foaming agent, 40 parts of alkali activator (the modulus and Na 2 O content of the alkali activator are 2.0 and 6% respectively), H 2 O 2 3 parts, 1 part of liquid polycarboxylate water reducer, and the co-grinding time of each cementitious material is 30 min.

[0143] The preparation method of the hollow self-insulating brick is the same as that of Example 1 in specific steps.

[0144] Example 7

[0145] An alkali-activated all-solid waste foamed concrete hollow self-insulating brick, the dosages of each component calculated by mass parts are respectively: 55 parts of waste incineration fly ash, 10 parts of fly ash, 6 parts of coal gangue, 16 parts of red mud, 8 parts of mackerel bone powder, 5 parts of silica gel desiccant powder, 1 part of polystyrene foam, 4 parts of hair fiber, 5 parts of physical foaming agent, 40 parts of alkali activator (the modulus and Na 2 O content of the alkali activator are 2.0 and 10% respectively), H 2 O 2 2 parts, 1 part of liquid polycarboxylate water reducer, and the co-grinding time of each cementitious material is 10 min.

[0146] The preparation method of the hollow self-insulating brick is the same as that of Example 1 in specific steps.

[0147] Example 8

[0148] An alkali-activated all-solid waste foam concrete hollow self-insulating brick, the dosages of each component calculated by mass fraction are as follows: 55 parts of waste incineration fly ash, 10 parts of fly ash, 6 parts of coal gangue, 16 parts of red mud, 8 parts of mackerel bone powder, 5 parts of silica gel desiccant powder, 1 part of polystyrene foam, 4 parts of hair fiber, 5 parts of physical foaming agent, 40 parts of alkali activator (the modulus and Na 2 O contents of the alkali activator are 2.5 and 6% respectively), H 2 O 2 2 parts, 1.5 parts of liquid polycarboxylate water reducer, and the co-grinding time of each cementitious material is 20 min.

[0149] The preparation method of the hollow self-insulating brick is the same as that of Example 1 in specific steps.

[0150] Example 9

[0151] An alkali-activated all-solid waste foam concrete hollow self-insulating brick, the dosages of each component calculated by mass fraction are as follows: 55 parts of waste incineration fly ash, 10 parts of fly ash, 6 parts of coal gangue, 16 parts of red mud, 8 parts of mackerel bone powder, 5 parts of silica gel desiccant powder, 1 part of polystyrene foam, 4 parts of hair fiber, 5 parts of physical foaming agent, 40 parts of alkali activator (the modulus and Na 2 O contents of the alkali activator are 1.5 and 8% respectively), H 2 O 2 2 parts, 1.5 parts of liquid polycarboxylate water reducer, and the co-grinding time of each cementitious material is 30 min.

[0152] The preparation method of the hollow self-insulating brick is the same as that of Example 1 in specific steps.

[0153] Control Example 1

[0154] An alkali-activated all-solid waste foam concrete hollow self-insulating brick, the dosages of each component calculated by mass fraction are as follows: 100 parts of cement, 4 parts of physical foaming agent, 40 parts of clear water.

[0155] Preparation steps:

[0156] Step 1: Weigh 100 parts of cement according to the mass fraction ratio and add it to a mixer, and slowly mix it at a speed of 150 rpm for 2 min;

[0157] Step 2: Mix 3 parts of physical foaming agent with water according to the mass fraction ratio, physical foaming agent: water = 1:5, and use a foaming device to control the air pump pressure value at 0.5 Pa to prepare delicate, uniform and milky white foam;

[0158] Step 4: Uniformly add 40 parts of clear water to the mixer and quickly mix it at a speed of 350 rpm for 5 min;

[0159] Step 5: Uniformly add the foam prepared in Step 2 into the slurry obtained in Step 4, and slowly stir at a speed of 150 rpm for 2 min to obtain a uniform foamed slurry;

[0160] Step 6: Pour the foamed slurry into a hollow self-insulating brick mold, and pre-cure it for 12 h in a closed curing environment with a temperature of 20 - 25 °C and a relative humidity ≥ 90%;

[0161] Step 7: Demold the mold, send the formed hollow self-insulating brick into an autoclave, and autoclave it for 12 h in an environment with a pressure of 1.5 MPa and a temperature of 200 °C;

[0162] Step 8: Slowly release the pressure in the autoclave. It can only be removed from the autoclave and demolded after the temperature drops below 60 °C to obtain the finished hollow self-insulating brick.

[0163] Control Example 2

[0164] For an alkali-activated all-solid waste foamed concrete hollow self-insulating brick, the dosages of each component are calculated by mass fraction as follows: 50 parts of incineration fly ash, 15 parts of fly ash, 11 parts of coal gangue, 11 parts of red mud, 1.7 parts of polystyrene foam, 2.6 parts of hair fiber, 3.5 parts of physical foaming agent, 34.8 parts of alkali activator (the modulus and Na 2 O content of the alkali activator are 1.5 and 10% respectively), H 2 O 2 2.6 parts, 1 part of liquid polycarboxylate water reducer, and the total grinding time of each cementitious material is 20 min.

[0165] The specific steps of the preparation method of this hollow self-insulating brick are the same as those in Example 1.

[0166] Control Example 3

[0167] For an alkali-activated all-solid waste foamed concrete hollow self-insulating brick, the dosages of each component are calculated by mass fraction as follows: 50 parts of waste incineration fly ash, 15 parts of fly ash, 11 parts of coal gangue, 11 parts of red mud, 6 parts of mackerel bone powder, 7 parts of silica gel desiccant powder, 4 parts of physical foaming agent, 40 parts of alkali activator (the modulus and Na 2 O content of the alkali activator are 1.5 and 10% respectively), H 2 O 2 3 parts, 1 part of liquid polycarboxylate water reducer, and the total grinding time of each cementitious material is 20 min.

[0168] Step 1: Weigh 50 parts of waste incineration fly ash, 15 parts of fly ash, 11 parts of coal gangue, 11 parts of red mud, 6 parts of mackerel bone powder, and 7 parts of silica gel desiccant powder according to the mass fraction ratio, and perform co-grinding through a planetary ball mill for uniform mixing and modification to obtain a mixed powder with a content ≥ 98%. The ball milling time is 20 min, and the ball milling speed is 300 rpm;

[0169] Step 2: Mix 3.5 parts of physical foaming agent with water according to the mass ratio of physical foaming agent: water = 1:5. Use a foaming machine and control the air pump pressure value at 0.5 Pa to prepare delicate, uniform, and milky white foam.

[0170] Step 3: Add the mixed powder into a stirrer, and then mix 34.8 parts of alkali activator, 2.6 parts of H 2 O 2 2, and 1 part of liquid polycarboxylate superplasticizer. The modulus and Na 2 O content of the alkali activator are 1.5 and 10% respectively. Uniformly add them into the stirrer and stir quickly at a speed of 350 rpm for 5 min to fully foam the H 2 O 2

[0171] Step 4: Uniformly add the foam prepared in Step 2 into the slurry obtained in Step 3 and stir slowly at a speed of 150 rpm for 2 min to obtain a uniform foamed slurry.

[0172] Step 5: Pour the foamed slurry into a hollow self-insulating brick mold and pre-cure it for 12 h in a closed curing environment with a temperature of 20 - 25°C and a relative humidity ≥ 90%.

[0173] Step 6: Demold the mold, send the formed hollow self-insulating brick into an autoclave, and autoclave it for 12 h in an environment with a pressure of 1.5 MPa and a temperature of 200°C.

[0174] Step 7: Slowly release the pressure in the autoclave. It can only be removed from the autoclave and demolded after the temperature drops below 60°C to obtain the finished hollow self-insulating brick.

[0175] Control Example 4

[0176] For an alkali-activated all-solid waste foamed concrete hollow self-insulating brick, the dosages of each component are calculated by mass as follows: 50 parts of waste incineration fly ash, 15 parts of fly ash, 11 parts of coal gangue, 11 parts of red mud, 6 parts of mackerel bone powder, 7 parts of silica gel desiccant powder, 2 parts of polystyrene foam, 3 parts of hair fiber, 4 parts of physical foaming agent, 40 parts of alkali activator (the modulus and Na 2 O content of the alkali activator are 1.5 and 10% respectively), 3 parts of H 2 O 2 , and 1 part of liquid polycarboxylate superplasticizer. Each gelling material is not co-ground.

[0177] Step 1: Add 50 parts of waste incineration fly ash, 15 parts of fly ash, 11 parts of coal gangue, 11 parts of red mud, 6 parts of mackerel bone powder, 7 parts of silica gel desiccant powder, 2 parts of polystyrene foam, and 3 parts of hair fiber into a stirrer and stir slowly at a speed of 120 - 150 rpm for 1 - 2 min to uniformly mix the gelling material and the filling material.

[0178] Step 2: Mix 4 parts of physical foaming agent with water according to the mass ratio of physical foaming agent: water = 1:5. Use a foaming machine and control the air pump pressure value at 0.5 Pa to prepare delicate, uniform and milky white foam;

[0179] Step 3: Mix 40 parts of alkali activator, 3 parts of H 2 O 2 3 and 1 part of liquid polycarboxylate water reducer. The modulus and Na 2 O content of the alkali activator are 1.5 and 10% respectively. Uniformly add them to a mixer and mix quickly at a speed of 350 rpm for 5 minutes to fully foam the H 2 O 2 ;

[0180] Step 4: Uniformly add the foam prepared in Step 2 to the slurry obtained in Step 3 and mix slowly at a speed of 150 rpm for 2 minutes to obtain a uniform foamed slurry;

[0181] Step 5: Pour the foamed slurry into a hollow self-insulating brick mold and pre-cure it for 12 hours in a closed curing environment at a temperature of 20 - 25°C and a relative humidity ≥ 90%;

[0182] Step 6: Demold the mold, send the formed hollow self-insulating brick into an autoclave, and autoclave it for 12 hours in an environment with a pressure of 1.5 MPa and a temperature of 200°C;

[0183] Step 7: Slowly release the pressure in the autoclave. It can only be removed from the autoclave and demolded after the temperature drops below 60°C to obtain the finished hollow self-insulating brick.

[0184] Performance test:

[0185] Test the heat transfer coefficient, compressive strength, dry shrinkage value and fire resistance rating of the self-insulating bricks prepared in Examples 1 - 9 and Comparative Examples 1 - 4. Among them, the heat transfer coefficient is based on GB / T 10294 - 2008 "Determination of Steady-State Thermal Resistance and Related Properties of Thermal Insulation Materials - Guarded Hot Plate Method", the compressive strength is based on GB / T 29062 - 2012 "Autoclaved Foamed Concrete Bricks and Blocks", the dry shrinkage value is based on GB / T 2542 - 2003 "Test Methods for Building Bricks", and the fire resistance rating is based on GB 8624 - 2012 "Classification of the Burning Performance of Building Materials and Products" and GB / T 5464 - 2010 "Test Method for Non-combustibility of Building Materials". The specific test results are shown in Table 1:

[0186] Table 1 Test results of various properties of self-insulating bricks

[0187]

[0188]

[0189] From the heat transfer coefficient and compressive strength data measured in the above nine groups of examples and four groups of control examples, it can be seen that the compressive strengths of the nine groups of examples reached 45.19%, 56.69%, 61.15%, 50.94%, 49.41%, 43.78%, 43.19%, 42.02%, and 42.96% of that of the pure cement control example 1 respectively. The heat insulation performance was improved by 44.74%, 36.84%, 28.95%, 50.00%, 52.63%, 57.89%, 23.68%, 26.32%, and 21.05% respectively compared with the pure cement control example. The dry shrinkage values were all ≤ 0.40 mm / m, and the fire resistance ratings were all A1.

[0190] Among the nine groups of examples, Example 5 had the best comprehensive performance. Its compressive strength reached 49.41% of that of the pure cement control example 1, and the heat insulation performance was improved by 52.63% compared with the pure cement control example. Compared with Control Example 2, Example 5 had comparable heat insulation performance and the strength was increased by 15.6%. The addition of mackerel bone powder and silica gel desiccant powder adjusted the Ca / Si molar ratio of the material. At the same time, the secondary hydration reaction ability of the silica gel desiccant powder could consume the excess Ca(OH) 2 to generate C-S-H gel, making the structure more dense. Compared with Control Example 3, Example 5 had the heat insulation performance improved by 48.60%. Waste polystyrene particles could effectively improve the heat insulation performance of the self-insulating brick. Compared with Control Example 4, Example 5 had the strength increased by 5.0%. Co-grinding could modify the surface of the material particles and improve the hydration activity.

[0191] In summary, it can be found that the hollow self-insulating brick produced from waste incineration fly ash, fly ash, coal gangue, red mud, mackerel bone powder, silica gel desiccant powder, polystyrene foam, and hair fiber as materials by using alkali activation technology, co-ball milling treatment, and a combination of physical foaming and chemical foaming can well meet the heat insulation, strength, durability, and fire protection requirements of self-insulating bricks.

Claims

1. An alkali-activated all-solid waste foamed concrete hollow self-insulating brick, characterized in that: The dosage of each component is calculated by mass ratio: 100 parts of cementitious material; 5 parts of filling material; 40-50 parts of alkali activator; 2-4 parts of H2O2; 3-5 parts of physical foaming agent; 1-1.5 parts of polycarboxylic acid water reducer; Among them, 100 parts of cementitious materials are composed of 45-55 parts of waste incineration fly ash, 10-20 parts of fly ash, 6-16 parts of coal gangue, 6-16 parts of red mud, 4-8 parts of fish bone powder, and 5-9 parts of silica gel desiccant powder; 5 parts of filling materials are composed of 1-3 parts of polystyrene foam and 2-4 parts of hair fiber.

2. The alkali-activated all-solid waste foamed concrete hollow self-insulating brick according to claim 1, characterized in that: The cementitious material is pretreated and then ball-milled together to obtain a mixed powder, and then the filler material is mixed with the mixed powder to obtain a mixture, and then the remaining components are used to chemically foam and physically foam the mixture in sequence, and then the mixture is put into a mold for steam pressing; wherein the chemical foaming agent is 30% H2O2; Fe2O3 rich in red mud and mackerel bone powder replaces traditional MnO2 to promote the decomposition of H2O2.

3. The alkali-activated all-solid waste foamed concrete hollow self-insulating brick according to claim 1, characterized in that: The CaO content in the waste incineration fly ash is ≥35%, and the Mohs hardness is 2-3; the SiO2 content in the fly ash is ≥35%, the Al2O3 content is ≥20%, and the Mohs hardness is 2-3; the SiO2 content in the coal gangue is ≥50%, the Al2O3 content is ≥40%, and the Mohs hardness is 5-6; the CaO content in the red mud is ≥15%, the Al2O3 content is ≥25%, the Fe2O3 content is ≥20%, the Na2O content is ≥10%, and the Mohs hardness is 4-5; the CaO content in the mackerel bone powder is ≥60%, the Fe2O3 content is ≥20%, and the Mohs hardness is 2-3; the SiO2 content in the silica gel desiccant powder is ≥98%, and the Mohs hardness is 6-7; the particle size of the polystyrene foam is 3-5mm.

4. The alkali-activated all-solid waste foamed concrete hollow self-insulating brick according to claim 1, characterized in that: The alkaline activator consists of a Na2SiO3 solution and solid NaOH, the modulus Ms of the Na2SiO3 solution is 3.0-3.6, and the purity of the solid NaOH is ≥98%, and is used to reduce the modulus of the Na2SiO3 solution.

5. The alkali-activated all-solid waste foamed concrete hollow self-insulating brick according to claim 1, characterized in that: The physical foaming agent is composed of 2.1-3.4 parts of physical foaming agent mother solution, 0.8-1.4 parts of sodium lauryl sulfate, and 0.1-0.2 parts of calcium stearate according to weight parts; the preparation process of the physical foaming agent mother solution is as follows: Step 1, wash the hair fibers and dry them at 45-60°C; Step 2, mix the dried hair fibers with deionized water in a ratio of 1:5-10 by mass, add H2O2 solution, then add NaOH solution, and adjust the pH to 9-12; Step 3, heating the hair fiber mixed solution in a constant temperature water bath at 90-100° C., wherein the hydrolysis time is 3-4 hours; Step 4: Cool and let stand; Step 5, filtering the hair fiber mixed solution after standing to obtain a clarified solution; Step 6: Adjust the pH of the clarified liquid to 7-8 with an acid solution while stirring. Step 7: The clarified liquid after adjusting the pH is filtered twice using qualitative filter paper with a pore size of 10-12 μm and concentrated.

6. The alkali-activated all-solid waste foamed concrete hollow self-insulating brick according to claim 1, characterized in that: The waste incineration fly ash undergoes a pretreatment process of primary drying, crushing, screening, alkali washing, suction filtration, water washing, suction filtration and secondary drying; the waste incineration fly ash pretreatment process is specifically as follows: Step 1, drying the waste incineration fly ash until the moisture content of the waste incineration fly ash is ≤0.5%; Step 2, crushing the waste incineration fly ash; Step 3, sieving the crushed waste incineration fly ash through a 150 μm square hole sieve, and collecting the waste incineration fly ash with a particle size of less than 150 μm for subsequent use; Step 4, mixing the waste incineration fly ash with a particle size less than 150 μm after screening with 40% NaOH solution, and mixing the NaOH solution: waste incineration fly ash in a mass ratio of 10:1 for mixed alkali washing, and then using magnetic stirring to promote the alkali washing process, the stirring rate is 20-30 rpm, and the stirring time is 30-60 min; Step 5: Let stand; Step 6: Filter to obtain solid waste incineration fly ash; Step 7, the filtered waste incineration fly ash and clean water are mixed in a mass ratio of clean water: waste incineration fly ash = 10:1, washed and stirred; Step 8: Let stand; Step 9, filtering to obtain solid waste incineration fly ash; Step 10: Dry the filtered waste incineration fly ash until the moisture content of the waste incineration fly ash is ≤0.5%.

7. The alkali-activated all-solid waste foamed concrete hollow self-insulating brick according to claim 1, characterized in that: The fly ash and coal gangue are dried so that their moisture content is ≤0.5%; the red mud needs to undergo a pretreatment process of primary drying, primary crushing, secondary drying, secondary crushing and screening to gradually reduce its moisture content so that the red mud moisture content is ≤0.5%, and the red mud with a particle size of less than 150μm under the sieve is screened and collected for subsequent use.

8. The alkali-activated all-solid waste foamed concrete hollow self-insulating brick according to claim 1, characterized in that: The fish bone powder is obtained by pre-treating mackerel bones through a process of primary washing, cooking, secondary washing, soaking, drying, crushing, heating and screening; the mackerel bone pre-treatment process is specifically as follows: Step 1. Wash the mackerel bones with clean water and cook for 30-45 minutes; Step 2: Rinse again to remove the remaining meat attached to the fish bones; Step 3, soak the mackerel bones after the second cleaning in a 0.5% NaOH solution for 2-3 hours, drain and soak in a 25% acetone solution for 7-8 hours; Step 4, drying at 105-120°C for 24-48h; Step 5: crushing; Step 6, placing the crushed mackerel bone powder in a heating furnace at 700-800° C. and heating for 2-3 hours; Step 7: Sieve the heated mackerel bone powder through a 150 μm square hole sieve, and collect the mackerel bone powder with a particle size less than 150 μm.

9. The alkali-activated all-solid waste foamed concrete hollow self-insulating brick according to claim 1, characterized in that: The silica gel desiccant powder is prepared from waste silica gel desiccant, and the specific preparation process of the silica gel desiccant powder is as follows: Step 1, purge the waste silica gel desiccant to remove dust on the surface; Step 2, drying; Step 3, crushing; Step 4: The silica gel desiccant powder obtained after crushing is sieved through a 150 μm square hole sieve, and the silica gel desiccant powder with a particle size of less than 150 μm under the sieve is collected.

10. A method for preparing the alkali-activated all-solid waste foamed concrete hollow self-insulating bricks according to any one of claims 1 to 9, characterized in that: After obtaining the pre-treated components, the hollow insulation bricks are prepared according to the following steps: Step 1, weighing 45-55 parts of waste incineration fly ash, 10-20 parts of fly ash, 6-16 parts of coal gangue, 6-16 parts of red mud, 4-8 parts of fish bone powder, and 5-9 parts of silica gel desiccant powder according to the mass ratio, and ball milling to obtain a mixed powder with a content of ≥98%; Step 2, adding the mixed powder, 1-3 parts of polystyrene foam and 2-4 parts of hair fibers into a blender to mix the gelling material and the filling material to obtain a mixture; Step 3, 3-5 parts of a physical foaming agent and water are mixed in a mass ratio of physical foaming agent: water = 1:2-8, and a fine and uniform milky white foam is prepared by controlling the air pump pressure value to 0.4-0.6 Pa in a foamer; Step 4, 40-50 parts of an alkali activator, 2-4 parts of H2O2 and 1-1.5 parts of a liquid polycarboxylate water reducer are mixed, wherein the modulus and Na2O content of the alkali activator are 1.5-2.5 and 6-10% respectively, and the mixture is uniformly added into a blender, and placed in the blender together with the mixture obtained in step f2, and stirred to make the H2O2 fully foamed; Step 5, adding the foam prepared in step f3 evenly to the slurry obtained in step f4, and stirring to obtain a uniform foaming slurry; Step 6: pour the foamed slurry into a hollow self-insulating brick mold and pre-cure it for 12 hours in a closed curing environment with a temperature of 20-25°C and a relative humidity of ≥90%; Step 7, remove the mold, send the formed hollow self-insulating brick into the autoclave, and autoclave for 12 hours at an air pressure of 1.2-1.5MPa and a temperature of 180-200°C; Step 8: After cooling and demoulding, hollow self-insulating bricks are obtained.

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