External wall self-insulation environment-friendly building block with high solid waste utilization rate and preparation method thereof

Abstract

The invention discloses an outer wall self-insulation environment-friendly building block with high solid waste utilization rate and a preparation method thereof, the outer wall self-insulation environment-friendly building block is particularly suitable for an outer wall structure of a low-rise building in a severe cold area, has the characteristics of high compressive strength, low heat conductivity coefficient, excellent freezing resistance, safety and environmental protection, and comprises a dense outer layer, a transition layer and a foaming core layer, the closed porosity is more than or equal to 80%, and the heat conductivity coefficient is less than or equal to 0.085 W / (m.K); the transition layer is arranged outside the foaming core layer, the thickness of the transition layer is 3 mm, the transition layer is used for blocking a thermal bridge, the interface bonding strength is larger than or equal to 1.2 MPa, and the thermal resistance value is larger than or equal to 0.15 m.K / W; the dense outer layer is arranged outside the transition layer, the thickness of the dense outer layer is 6 mm, and the compressive strength is larger than or equal to 20 MPa. Through polymer regenerated fiber reinforcement, layered composite design and CO2 carbonization processes, the compressive strength is larger than or equal to 10 MPa, the heat conductivity coefficient is smaller than or equal to 0.085 W / (m.K), the solid waste utilization rate is larger than or equal to 80%, the building block is suitable for severe cold to mild climate areas, the comprehensive cost is reduced by 40% compared with a traditional external thermal insulation system, and the environment-friendly, safe and economic benefits are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of building materials, in particular to a high-solid-waste-utilization-rate outer wall self-insulation environment-friendly block and a preparation method thereof, which is especially suitable for the outer wall structure of buildings in severe cold regions and has high compressive strength, low thermal conductivity, excellent frost resistance and safe and environmentally friendly properties. BACKGROUND

[0002] The self-insulation environment-friendly block refers to a new type of wall material that integrates the insulation function in the block body, does not require an additional outer wall insulation layer to meet the building energy-saving insulation requirements, and is made of environmentally friendly raw materials or by-product resources, and has the advantages of energy saving, environmental protection, convenient construction and the like.

[0003] The traditional outer wall material has the following problems:

[0004] 1. Performance imbalance: the insulation material (such as polystyrene board) has low strength (compressive strength ≤ 3 MPa) and cannot bear weight; the high-strength block (such as concrete hollow brick) has high thermal conductivity (≥0.6 W / (m·K)) and needs to be attached to an external insulation layer, which increases the construction cost by 35%, and is accompanied by quality problems such as cracking, hollowing, leakage, and even falling of the insulation layer.

[0005] 2. Low solid waste utilization rate: the conventional block has a building waste content of less than 20%, and the performance of the recycled aggregate is unstable, which easily leads to cracking.

[0006] 3. Health risk: some materials (such as glass fibers) release harmful dust during processing, which is harmful to human health.

[0007] 4. Insufficient durability: the mass loss rate is ≥8% after freeze-thaw cycles, the water absorption rate is ≥10%, and the insulation performance decreases significantly after long-term use. Therefore, it is urgent to design a high-solid-waste-utilization-rate outer wall self-insulation environment-friendly block and a preparation method thereof. SUMMARY

[0008] (I) Technical problems solved

[0009] In view of the deficiencies of the prior art, the present application provides a high-solid-waste-utilization-rate outer wall self-insulation environment-friendly block, which solves the technical problems of performance imbalance, low solid waste utilization rate, health risk and insufficient durability of the prior art.

[0010] (II) Technical solutions

[0011] To achieve the above object, the present application is implemented by the following technical scheme: A high solid waste utilization rate external wall self-insulation environment-friendly building block, comprising a dense outer layer, a transition layer and a foamed core layer, the thickness of the foamed core layer is 182mm, which is the main body of heat preservation, the closed porosity is greater than or equal to 80%, and the thermal conductivity is less than or equal to 0.085 W / (m·K); the transition layer is arranged outside the foamed core layer and has a thickness of 3mm, which is used for blocking the thermal bridge, the interface bonding strength is greater than or equal to 1.2MPa, and the thermal resistance value is greater than or equal to 0.15m²·K / W; the dense outer layer is arranged outside the transition layer and has a thickness of 6mm, and the compressive strength is greater than or equal to 20MPa.

[0012] As a further preferred mode of the present application, the mass percentage of the dense outer layer is:

[0013] 3-5mm of construction waste recycled coarse aggregate 40-50%;

[0014] S95 grade of slag powder 25-35%;

[0015] Recycled micro powder 15-25%;

[0016] Methyl sodium silicate waterproof agent 0.5-1.5%;

[0017] Polypropylene fiber 3-5%.

[0018] As a further preferred mode of the present application, the mass percentage of the transition layer is,

[0019] 0-1.5mm of construction waste fine aggregate 35-45%;

[0020] Inorganic lightweight aggregate 15-25%;

[0021] Polymer recycled fiber 6-9%;

[0022] Calcined kaolin 12-22%;

[0023] Silane coupling agent 0.3-0.7%;

[0024] The balance of recycled micro powder;

[0025] The polymer recycled fiber is selected from recycled PET, PP or PA fiber, the length is less than or equal to 3mm, and the tensile strength is greater than or equal to 300MPa; the fiber surface is modified by a silane coupling agent, and the coating amount is 0.3-0.7% of the mass of the fiber;

[0026] The inorganic lightweight aggregate is expanded vermiculite or vitrified microsphere, and the particle size is 0.1-2mm; the expanded vermiculite is treated by calcination at a calcination temperature of 800-1000℃, and the specific surface area is greater than or equal to 5m² / g.

[0027] As a further preferred mode of the present application, the mass percentage of the foamed core layer is,

[0028] S95 grade slag powder 20-30%;

[0029] Recycled micro powder 35-45%;

[0030] Expanded vitrified microsphere 10-20%;

[0031] H2O2 foaming agent 0.3-0.8%;

[0032] Silica fume 3-6%;

[0033] Alkali metal salt type activator 1-2%.

[0034] As a further preferred mode of the present application, the alkali metal salt type activator is NaOH or KOH, the specific surface area of the slag powder is ≥400 m2 / kg, and the 7d activity index is ≥95%; the recycled micro powder is a building waste grinding product, the 45 μm sieve residue is ≤15%, and the water demand ratio is ≤105%; and the mass ratio of the S95 grade slag powder to the recycled micro powder is 1:1.2-1:1.8.

[0035] As a further preferred mode of the present application, the specific steps include the following steps,

[0036] S1, raw material pretreatment:

[0037] The building waste aggregate is treated by pickling, the acid concentration is 3-7%, and the time is 1-3 h to remove surface impurities; the polymer recycled fiber is pretreated by cutting to ≤3 mm, then immersed in a silane coupling agent solution with a concentration of 1-3% for 10-20 minutes, and then dried at 60-80°C to a water content of ≤1%;

[0038] S2, layered forming:

[0039] Surface layer: after wet mixing of the slurry, high-frequency vibration compaction is performed at 25-35 Hz x 50-70 s and a pressure of 0.05-0.15 MPa;

[0040] Transition layer: high-pressure spraying is performed at a pressure of 0.3 MPa, followed by light vibration to remove bubbles;

[0041] Core layer: low-pressure foaming of the core layer is performed at a pressure of 0.05-0.1 MPa and a rolling speed of 2-5 m / min;

[0042] S3, curing process:

[0043] Steam curing: 70-85°C x 8-12h, humidity ≥90%;

[0044] Carbonation curing: CO2 carbonation curing at a concentration of 18-22% x 4-6h and a pressure of 0.1-0.2 MPa;

[0045] Natural curing: room temperature curing for 28 days.

[0046] As a further preferred mode of the present application, in step S3, the CO2 carbonization in the carbonization curing process is carried out in two stages, Stage One: concentration 15-18%, pressure 0.1 MPa, time 2 h; Stage Two: concentration 20-25%, pressure 0.2 MPa, time 4 h; the surface CaCO3 formation rate after carbonization curing is ≥60%, and the carbonization depth is ≥3 mm.

[0047] (Three) beneficial effects

[0048] The present application provides a high solid waste utilization rate self-insulation environmental protection block for outer wall and a preparation method thereof. The present application has the following beneficial effects:

[0049] I. Environmental protection and safety: solid waste utilization rate ≥80% (recycled aggregate + slag + recycled PET fiber), annual consumption of construction waste 12,000 tons per production line; in line with green building material standards; safe and environmentally friendly: recycled PET fiber is used to replace glass fiber to avoid dust hazards. The leaching solution of recycled PET fiber contains no heavy metals (GB / T 30810-2014), the construction dust concentration is ≤1 mg / m³, and the carbon emission in the whole life cycle is 28 kg CO2 / m³ (traditional system 85 kg CO2 / m³), which reduces carbon by 67%, and reduces carbon by 52,000 tons (equivalent to 290,000 trees per year) per 100,000 square meters of building.

[0050] II. Carbon reduction benefit: the block realizes carbon emission ≤32 kg CO2 / m³ in the whole life cycle through high solid waste mixing, recycled fiber application and CO2 carbonization curing process, which is 65-68% lower than the traditional outer wall system. Single project (100,000 m² building) application can reduce CO2 emission ≈5200 tons, equivalent to the annual carbon sequestration of 290,000 adult trees.

[0051] III. Construction and durability advantages, construction period shortened: one-piece molding process reduces 3 construction links, and the construction period is compressed by 50%; durability guarantee: strength retention rate ≥90% after 100 times of wet heat cycle (70℃ / 95%RH); surface powdering grade ≤1 level (ASTM D4214) after ultraviolet aging (QUV 2000h). BRIEF DESCRIPTION OF DRAWINGS

[0052] Fig. 1 It is a sectional structure schematic view of the block of the present application;

[0053] Fig. 2 It is a method flow schematic view of the present application.

[0054] 1-dense outer layer, 2-transition layer, 3-foamed core layer. DETAILED DESCRIPTION

[0055] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0056] Please refer to Figs. 1-2 The embodiment of the present application provides a technical solution: a high solid waste utilization rate external wall self-insulation environment-friendly block, comprising a dense outer layer, a transition layer and a foamed core layer, the thickness of the foamed core layer is 182mm, which is the main body of heat preservation, the closed porosity is greater than or equal to 80%, and the thermal conductivity is less than or equal to 0.085W / (m·K); the transition layer is arranged outside the foamed core layer and has a thickness of 3mm, which is used for blocking thermal bridges, the interface bonding strength is greater than or equal to 1.2MPa, and the thermal resistance value is greater than or equal to 0.15m²·K / W; the dense outer layer is arranged outside the transition layer and has a thickness of 6mm, and the compressive strength is greater than or equal to 20MPa.

[0057] The mass percentage of the dense outer layer is:

[0058] 3-5mm of construction waste recycled coarse aggregate 40-50%;

[0059] S95 grade of slag powder 25-35%;

[0060] Recycled fine powder 15-25%;

[0061] Methyl sodium silicate waterproof agent 0.5-1.5%;

[0062] Polypropylene fiber 3-5%.

[0063] The mass percentage of the transition layer is,

[0064] 0-1.5mm of construction waste fine aggregate 35-45%;

[0065] Inorganic lightweight aggregate 15-25%;

[0066] Polymer recycled fiber 6-9%;

[0067] Calcined kaolin 12-22%;

[0068] Silane coupling agent 0.3-0.7%;

[0069] The balance of recycled fine powder;

[0070] The polymer recycled fiber is selected from recycled PET, PP or PA fiber, the length is less than or equal to 3mm, and the tensile strength is greater than or equal to 300MPa; the surface of the fiber is modified and treated by a silane coupling agent, and the coating amount is 0.3-0.7% of the mass of the fiber;

[0071] The inorganic lightweight aggregate is expanded vermiculite or vitrified microsphere, and the particle size is 0.1-2 mm; the expanded vermiculite is treated by calcination, the calcination temperature is 800-1000 DEG C, and the specific surface area is greater than or equal to 5 m2 / g.

[0072] The mass percentage of the foamed core layer is,

[0073] The slag powder of S95 level is 20-30%;

[0074] The recycled micro powder is 35-45%;

[0075] The expanded vitrified microsphere is 10-20%;

[0076] The H2O2 foaming agent is 0.3-0.8%;

[0077] The silica ash is 3-6%;

[0078] The alkali metal salt type activator is 1-2%.

[0079] The alkali metal salt type activator is NaOH or KOH, the specific surface area of the slag powder is greater than or equal to 400 m2 / kg, and the 7d activity index is greater than or equal to 95%; the recycled micro powder is a building waste grinding product, the 45 mu m sieve residue is less than or equal to 15%, the water demand ratio is less than or equal to 105%, and the mass ratio of the slag powder of S95 level to the recycled micro powder is 1:1.2-1:1.8.

[0080] A preparation method of a high-solid-waste-utilization-rate external wall self-insulation environment-friendly building block, and the specific steps include the following steps,

[0081] S1, raw material pretreatment:

[0082] The building waste aggregate is treated by pickling, the acid concentration is 3-7%, and the time is 1-3h, so as to remove the surface impurities; the polymer recycled fiber is pretreated: after being cut to less than or equal to 3 mm, it is immersed in a silane coupling agent solution with a concentration of 1-3% for 10-20 minutes; and then it is dried at 60-80 DEG C until the water content is less than or equal to 1%;

[0083] S2, layered forming:

[0084] The surface layer is densely compacted by high-frequency vibration after wet mixing of the slurry, the vibration frequency is 25-35 Hz, the vibration time is 50-70 s, and the pressure is 0.05-0.15 MPa;

[0085] The transition layer is sprayed by high pressure, and the pressure is 0.3 MPa, and then light vibration is used for defoaming;

[0086] The core layer is foamed by low pressure, the pressure is 0.05-0.1 MPa, and the rolling speed is 2-5 m / min;

[0087] S3, curing process:

[0088] Steam curing: 70-85 DEG C x 8-12h, humidity greater than or equal to 90%.

[0089] Carbonation maintenance: CO2 carbonation maintenance, concentration 18-22% x 4-6h, pressure 0.1-0.2MPa;

[0090] Natural maintenance: room temperature maintenance for 28 days.

[0091] In step S3, during the carbonation maintenance, CO2 carbonation is carried out in two stages, stage one: concentration 15-18%, pressure 0.1MPa, time 2h; stage two: concentration 20-25%, pressure 0.2MPa, time 4h; after carbonation maintenance, the surface CaCO3 formation rate is ≥60%, and the carbonation depth is ≥3mm.

[0092] Example one

[0093] Load-bearing type external wall block in severe cold regions,

[0094] Raw material pretreatment: building waste coarse aggregate (3-5mm) is soaked in 5% hydrochloric acid for 2 hours to remove mud impurities and heavy metal attachments, and is dried after cleaning for standby use;

[0095] Polypropylene regenerated fibers are cut to 2mm, immersed in a 2% γ-aminopropyl triethoxysilane solution for 15 minutes, and dried to a water content of ≤1%.

[0096] Layered molding:

[0097] Material mass percentage of dense outer layer (6mm thick):

[0098] Building waste recycled coarse aggregate: 45%

[0099] S95 grade slag powder: 30%

[0100] Recycled micro powder: 20%

[0101] Methyl sodium silicate waterproofing agent: 1%

[0102] Polypropylene fiber: 4%

[0103] After wet mixing, high-frequency vibration is carried out at 30Hz for 60s, and the molding pressure is 0.1MPa;

[0104] Material mass percentage of transition layer (3mm thick):

[0105] Building waste fine aggregate (≤1.5mm): 40%

[0106] Expanded vermiculite (calcined at 900℃): 20%

[0107] Polyester regenerated fiber: 8%, tensile strength about 380MPa

[0108] Calcined kaolin clay: 15%

[0109] Recycled micro-fines: 16.5%

[0110] Silane coupling agent (for fiber surface): 0.5%

[0111] High pressure spray forming, spray pressure 0.3 MPa;

[0112] Foamed core layer (thickness 182 mm) material mass percentage:

[0113] S95 slag powder: 25%

[0114] Recycled micro-fines: 40%

[0115] Expanded vitrified microbeads: 15%

[0116] Silica fume: 4%

[0117] H2O2 foaming agent: 0.5%

[0118] NaOH activator: 1.5%

[0119] The mixture is injected into the mold at low pressure, and the rolling rate is 4 m / min, and the closed porosity reaches 82%.

[0120] Curing process:

[0121] Steam curing: 80℃×10h, humidity ≥95%;

[0122] Carbonation curing: CO2 concentration 20%, pressure 0.2 MPa, 4h;

[0123] Natural curing: 28 days;

[0124] The final formation of the surface CaCO3 generation rate reaches 65%, and the carbonation depth is about 3.5 mm.

[0125] Performance test:

[0126] Compressive strength: 12.2 MPa;

[0127] Heat transfer coefficient: 0.419 W / (m²·K);

[0128] Freeze-thaw mass loss: 4.2%.

[0129] It is calculated that the carbon emission of the block in the embodiment is 28kg CO2 / m³, and the carbon sequestration of CO2 carbonation curing is 4.2kg / m³.

[0130] Example Two

[0131] Applicable to mild climate areas, used for enhanced block products of high-rise buildings, suitable for southern rainy environment:

[0132] Raw material ratio and treatment:

[0133] Dense outer layer: coarse aggregate 50%, S95 slag powder 25%, recycled micro powder 15%, waterproofing agent 1.2%, polypropylene fiber 3.8%;

[0134] Transition layer: construction waste fine aggregate 45%, vitrified microbead 15%, PET fiber (tensile strength > 320 MPa) 9%, calcined kaolin 13%, recycled micro powder 17%, silane coupling agent 0.6%;

[0135] Foamed core layer: S95 slag powder 22%, recycled micro powder 40%, vitrified microbead 18%, silica fume 3%, H2O2 0.4%, KOH 1.6%;

[0136] Forming process:

[0137] Surface layer high frequency vibration 32 Hz x 55 s;

[0138] Transition layer high pressure spraying + rotary atomizing device;

[0139] Core layer low pressure injection + dynamic rheological control system;

[0140] Curing method:

[0141] Steam curing: 75℃ x 12h;

[0142] Carbonation curing two stages:

[0143] First stage: concentration 18%, pressure 0.1 MPa, 2h;

[0144] Second stage: concentration 23%, pressure 0.2 MPa, 4h;

[0145] CaCO3 generation rate reached 62%, carbonation depth 3.8mm.

[0146] Example three

[0147] High frost resistance variant suitable for lightweight thermal insulation wall of energy-saving buildings in cold regions:

[0148] Raw material composition:

[0149] Dense outer layer:

[0150] Coarse aggregate 40%, slag powder 33%, recycled micro powder 20%, waterproofing agent 1.3%, polypropylene fiber 4.7%;

[0151] Transition layer: construction fine aggregate 38%, expanded vermiculite 22%, PP fiber 7% (modified by silane), kaolin 18%, recycled micro powder 14%, silane coupling agent 0.5%;

[0152] Foamed core layer: S95 slag powder 30%, recycled micro powder 36%, vitrified microbead 12%, H2O2 0.7%, silica fume 5%, NaOH 1.2%;

[0153] Process control:

[0154] Outer layer pressure 0.15 MPa, high-frequency vibration 35 Hz;

[0155] Core layer foaming pressure control at 0.08 MPa, foaming time 20 minutes;

[0156] Transition layer defoaming vibration control at 15 Hz for 30 seconds;

[0157] Curing parameters:

[0158] Steam curing: 85℃×8h;

[0159] CO2 carbonation curing: concentration 21%, pressure 0.2 MPa, 5h;

[0160] Surface layer CaCO3 deposition rate reached 68%, carbonation depth 4.1mm.

[0161] Performance comparison of this block with traditional outer wall system:

[0162]

[0163] Performance breakthrough:

[0164] Compressive strength ≥10 MPa, meeting the load-bearing requirements of low-rise buildings;

[0165] Thermal conductivity coefficient ≤0.45 W / (m²·K), no additional external insulation layer is needed;

[0166] Excellent frost resistance: mass loss ≤5% after 50 freeze-thaw cycles;

[0167] Fire resistance limit ≥2.5h (ISO 834).

[0168] Cost optimization

[0169]

[0170] The foregoing merely illustrates the principles of the application and application of its leading features. This application is not limited to the illustrative embodiments shown and described herein. Rather, the scope of the present application is defined by the appended claims, and other embodiments of this application will readily occur to those skilled in the art. Accordingly, the application is not limited to that described in the foregoing description or illustrated in the accompanying drawings. It is intended to cover any adaptations or variations of the present application and to encompass within the scope of the patent the appropriate scope of equivalents. Any and all embodiments of the present application can be practiced alone or in combination with one another. Thus, individual features of embodiments of this application can be used in combinations other than the combinations explicitly described herein. It is intended that each of the claims is defined not only by the elements embodied in the claim, but also by the alternative embodiments of the elements embodied in the claim. Moreover, no reference signs in the claims are intended to be critical to the recited claim elements, nor are they intended to mean that the claimed elements are limited to the specific embodiments described herein.

[0171] Furthermore, it should be understood that although the description of the present application is made on the basis of the embodiments, not every embodiment contains only one independent technical solution, and the description of the present application is made in this way only for the sake of clarity, and those skilled in the art should understand the present application as a whole, and the technical solutions in each embodiment can also be combined appropriately to form other embodiments that those skilled in the art can understand.

Claims

1. A high-solid-waste-utilization-rate self-insulating environmentally friendly exterior wall block, characterized in that: The foam core layer is the main heat preservation body, the closed porosity is greater than or equal to 80%, and the thermal conductivity is less than or equal to 0.085 W / (m*K); the transition layer is arranged outside the foam core layer and has a thickness of 3 mm, is used for blocking thermal bridges, has an interface bonding strength greater than or equal to 1.2 MPa, and has a thermal resistance value greater than or equal to 0.15 m2*K / W; and the dense outer layer is arranged outside the transition layer and has a thickness of 6 mm and a compressive strength greater than or equal to 20 MPa.

2. The high solid waste utilization rate self-insulation environment-friendly exterior wall building block according to claim 1, characterized in that: The dense outer layer has a mass percentage of: 3-5mm of construction waste recycled coarse aggregate 40-50%; S95 grade of slag powder 25-35%; Recycled micro powder 15-25%; Methyl sodium silicate waterproof agent 0.5-1.5%; Polypropylene fiber 3-5%.

3. The high solid waste utilization rate self-insulation environment-friendly exterior wall building block according to claim 1, characterized in that: The transition layer has a mass percentage of, 0-1.5mm of construction waste fine aggregate 35-45%; Inorganic lightweight aggregate 15-25%; Polymer recycled fiber 6-9%; Calcined kaolin 12-22%; Silane coupling agent 0.3-0.7%; The rest is recycled micro powder; The polymer recycled fiber is selected from recycled PET, PP or PA fiber, has a length less than or equal to 3 mm and a tensile strength greater than or equal to 300 MPa; the fiber surface is modified by a silane coupling agent, and the coating amount is 0.3-0.7% of the mass of the fiber; The inorganic lightweight aggregate is expanded vermiculite or vitrified microsphere, and has a particle size of 0.1-2 mm; the expanded vermiculite is calcined at a calcination temperature of 800-1000 DEG C, and has a specific surface area greater than or equal to 5 m2 / g.

4. The high solid waste utilization rate self-insulation environment-friendly exterior wall building block according to claim 1, characterized in that: The foam core layer has a mass percentage of, S95 grade of slag powder 20-30%; Recycled micro powder 35-45%; Expanded vitrified microsphere 10-20%; H2O2 foaming agent 0.3-0.8%; Silica fume 3-6%; Alkali salt type activator 1-2%.

5. The high solid waste utilization rate self-insulation environment-friendly exterior wall building block according to claim 4, characterized in that: The alkali salt type activator is NaOH or KOH, the slag powder has a specific surface area greater than or equal to 400 m2 / kg, and a 7d activity index greater than or equal to 95%; the recycled micro powder is a grinding product of construction waste, has a 45 mu m residue less than or equal to 15%, and a water demand ratio less than or equal to 105%; and the mass ratio of the S95 grade of slag powder to the recycled micro powder is 1:1.2-1:1.

8.

6. A method for preparing the high solid waste utilization rate self-insulation environment-friendly exterior wall building block of claims 1-5, characterized in that: The specific steps include the following steps, S1, raw material pretreatment: The construction waste aggregate is treated by pickling, the acid concentration is 3-7%, and the time is 1-3 h to remove surface impurities; The polymer recycled fiber is pretreated by being cut to less than or equal to 3 mm and then immersed in a silane coupling agent solution with a concentration of 1-3% for 10-20 minutes; Drying at 60-80 DEG C to a water content of less than or equal to 1%; S2, layered forming: Surface layer: after wet mixing of the slurry, high-frequency vibration compaction is carried out at 25-35 Hz x 50-70 s and a pressure of 0.05-0.15 MPa; Transition layer: high-pressure spraying is carried out at a pressure of 0.3 MPa, and then light vibration is carried out for defoaming; Core layer: low-pressure foaming of the core layer is carried out at a pressure of 0.05-0.1 MPa and a rolling rate of 2-5 m / min; S3, curing process: Steam curing: 70-85 DEG C x 8-12 h, humidity greater than or equal to 90%; Carbonization curing: CO2 carbonization curing, concentration 18-22% x 4-6 h, pressure 0.1-0.2 MPa; Natural curing: room temperature curing for 28 days.

7. The method for preparing a high solid waste utilization rate self-insulating environmentally friendly exterior wall block according to claim 6, characterized in that: In step S3, the carbonization curing process is divided into two stages. Stage one: concentration 15-18%, pressure 0.1 MPa, time 2 h; stage two: concentration 20-25%, pressure 0.2 MPa, time 4 h. After carbonization curing, the surface CaCO3 formation rate is greater than or equal to 60%, and the carbonization depth is greater than or equal to 3 mm.

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