Fire-resistant and heat-insulating smoke exhaust air duct and preparation method thereof

Abstract

The present application relates to the field of fire-fighting smoke exhaust building materials, and particularly relates to a fire-resistant and heat-insulating smoke exhaust air duct and a preparation method thereof. The fire-resistant and heat-insulating smoke exhaust air duct comprises a galvanized steel plate, a color steel plate and a porous heat-insulating fireproof layer fixedly connected between the galvanized steel plate and the color steel plate; an inorganic sealing layer A is formed on the upper surface of the porous heat-insulating fireproof layer; an inorganic sealing layer B is formed on the upper surface of the porous heat-insulating fireproof layer; the inorganic sealing layer A is fixedly connected to the inner wall of the color steel plate through an inorganic adhesive layer A; and the inorganic sealing layer B is fixedly connected to the inner wall of the galvanized steel plate through an inorganic adhesive layer B. The smoke exhaust air duct has good fire-resistant and heat-insulating performance and a density of less than or equal to 0.8 g / cm 3 , and thus light-weight design is achieved, and the smoke exhaust air duct is convenient to transport, carry, assemble and construct, and the assembly cost of the smoke exhaust system is reduced.

Description

Technical Field

[0001] This invention relates to the field of fire-fighting smoke exhaust building materials, and in particular to a fire-resistant and heat-insulating smoke exhaust duct and its preparation method. Background Technology

[0002] The function of a smoke control system is to prevent smoke from entering evacuation routes and ensure the fire safety of a building. Smoke control systems mainly consist of smoke control ducts, which supply and exhaust air to prevent smoke from entering evacuation routes. According to the current national standard GB / T 51251-2017, the fire resistance rating of smoke control ducts should be ≥0.5h. In special cases, the fire resistance rating of smoke control ducts installed indoors should be ≥1.0h, and the fire resistance rating of smoke exhaust ducts within corridor ceilings or passing through fire compartments should be ≥1.0h.

[0003] Early designs for smoke extraction ducts mainly fell into three categories:

[0004] The first type of smoke exhaust duct is composed of galvanized iron sheet + 50mm rock wool + 8-12mm fireproof board, which has the following problems: it needs to be fabricated on site, the assembly rate is very low, the labor cost is high, and the cost is relatively high.

[0005] The second type of smoke exhaust duct is composed of galvanized iron sheet + heat insulation adhesive + 50mm thick flexible high-temperature resistant centrifugal glass wool. The high-temperature resistant centrifugal glass wool is wrapped on the outside of the iron sheet, and then aluminum foil is wrapped on the outside of the high-temperature resistant centrifugal glass wool. It has the following problems: the aluminum foil is easily damaged, resulting in the heat insulation layer being exposed, which has poor durability, occupies a lot of space, requires a lot of on-site work, and has a high cost.

[0006] The third type of smoke exhaust duct is an industrial integrated composite panel composed of three layers: sheet metal, calcium silicate filament, and rock wool. As a wrapping material, it needs to be wrapped around the sheet metal duct to extend the fire resistance limit. However, the cost is relatively high and the weight is also relatively heavy, which puts higher requirements on the supporting structure of the smoke exhaust duct.

[0007] The three main types of smoke exhaust ducts mentioned above present challenges in construction, are relatively heavy, and are inconvenient for installation and assembly. Therefore, technicians have optimized the structural design of the smoke exhaust ducts. Currently, the mainstream smoke exhaust ducts are composite ducts, which are constructed from inner and outer color steel plates or inner and outer sheet metal + silicate fireproof board or magnesium oxide fireproof board. The core material with a fire resistance rating of 0.5 hours is 8-9 mm thick, and the core material with a fire resistance rating of 1.0 hour is 14-15 mm thick. Although this reduces the overall weight while ensuring the fire resistance rating, its thermal conductivity as a homogeneous material is above 0.2 W / mK. This high thermal conductivity means it lacks fire resistance and insulation properties, requiring further design optimization. Furthermore, the average density of the fireproof board is 1.0 g / cm³. 3 The overall design is too heavy and requires further lightweighting improvements. Therefore, there is an urgent need for a lightweight, easy-to-assemble, and easy-to-install fire-resistant and heat-insulating smoke exhaust duct. Summary of the Invention

[0008] In view of the technical problems existing in the existing smoke control and exhaust ducts, the present invention provides a fire-resistant and heat-insulating smoke control and exhaust duct and its preparation method.

[0009] The fire-resistant and heat-insulating smoke exhaust duct provided by this invention is achieved through the following solution:

[0010] A fire-resistant and heat-insulating smoke exhaust duct includes a galvanized steel sheet, a color steel sheet, and a porous heat-insulating and fireproof layer fixedly connected between the galvanized steel sheet and the color steel sheet; an inorganic sealing layer A is formed on the upper surface of the porous heat-insulating and fireproof layer; an inorganic sealing layer B is formed on the lower surface of the porous heat-insulating and fireproof layer; the inorganic sealing layer A is fixedly connected to the inner wall of the color steel sheet by an inorganic adhesive layer A; the inorganic sealing layer B is fixedly connected to the inner wall of the galvanized steel sheet by an inorganic adhesive layer B.

[0011] The smoke exhaust duct of this invention has good fire resistance and heat insulation properties and its density is ≤0.8g / cm³. 3 It achieves a lightweight design, which facilitates the transportation, handling, assembly, and construction of smoke exhaust ducts, and reduces the assembly cost of smoke exhaust systems.

[0012] Preferably, the porous heat-insulating and fire-resistant layer is a porous heat-insulating and fire-resistant material, and the preparation method of the porous heat-insulating and fire-resistant material includes the following steps:

[0013] Step 1: Perform surface grafting modification treatment on the porous thermal insulation substrate;

[0014] Simultaneously, the layered two-dimensional nanofiller was subjected to surface grafting modification treatment;

[0015] Step 2: Disperse the surface-grafted modified layered two-dimensional nanofillers in a solvent to obtain a pre-impregnation dispersion system;

[0016] Step 3: Immerse the surface-modified porous thermal insulation substrate in the prepreg dispersion system of Step 2, keep it at 40-45℃ for 30-60 minutes, remove the solvent, so that the layered two-dimensional nanofiller is uniformly loaded inside the aerogel thermal insulation felt to obtain a semi-finished porous thermal insulation and fireproof material.

[0017] Step four: Place the semi-finished porous heat-insulating and fire-resistant material at 80-140℃ for 0.5-2 hours to obtain the finished porous heat-insulating and fire-resistant material.

[0018] Preferably, the porous thermal insulation substrate in step one is an aerogel insulation felt, and the thickness of the aerogel insulation felt is 2mm, 3mm, 5mm, 6mm, 9mm, or 10mm.

[0019] Preferably, the porous thermal insulation substrate is selected from any one of thermal insulation felt FMD450, thermal insulation felt FMB350, thermal insulation felt FMB400, thermal insulation felt FMC200, thermal insulation felt FMA400, and thermal insulation felt FMA650.

[0020] Preferably, the layered two-dimensional nanofiller is one or more of boron nitride, molybdenum disulfide, and tungsten disulfide.

[0021] Preferably, in step one, the porous thermal insulation substrate is subjected to surface grafting modification treatment, specifically as follows: the porous thermal insulation substrate is immersed in a 0.5-5wt% aqueous solution of methacryloyloxysilane in ethanol, stirred for 5-60 minutes, then removed and dried to obtain the porous thermal insulation substrate with surface grafting methacryloyloxysilane modification treatment.

[0022] Preferably, the layered two-dimensional nanofiller is subjected to surface grafting modification treatment as follows: the layered two-dimensional nanofiller is immersed in a 0.5-5wt% mercaptosilane ethanol aqueous solution, stirred for 5-60 minutes, removed and dried to obtain the layered two-dimensional nanofiller with surface grafted mercaptosilane.

[0023] Preferably, in step two, the surface-grafted modified layered two-dimensional nanofiller is dispersed in supercritical carbon dioxide to obtain a pre-impregnation dispersion system. The temperature of the supercritical carbon dioxide is 40-45℃ and the pressure is 10-15MPa.

[0024] The content of layered two-dimensional nanofillers in porous thermal insulation and fireproof materials affects their fire resistance limit. Taking aerogel insulation felt with a thickness of 2mm as an example, loading 5wt% boron nitride nanosheets can meet the requirement of a fire resistance limit of ≥1.0h. Using supercritical carbon dioxide as a solvent can effectively improve the environmental performance of porous thermal insulation and fireproof materials, increase their production efficiency, and reduce the cost of industrial waste treatment.

[0025] Preferably, both inorganic plugging layer A and inorganic plugging layer B are formed by curing an inorganic plugging agent; the inorganic plugging agent is made of a metal oxide composite sol system and a low-density thermal insulation filler; the content of the low-density thermal insulation filler in the inorganic plugging agent is 5-50 wt%; the metal oxide composite sol system is an aluminum hydroxide / silica composite sol prepared by the sol-gel method; or the metal oxide composite sol system is a titanium dioxide / silica composite sol prepared by the sol-gel method.

[0026] Inorganic sealing layer A and inorganic sealing layer B can effectively reduce the probability of burn-through of porous heat insulation and fireproof layer and improve the overall fire resistance and heat insulation performance.

[0027] Preferably, the low-density thermal insulation filler is at least one of hollow glass microspheres and aerogel powder; the true density of the hollow glass microspheres is ≤0.65 g / cm³. 3 The true density of the aerogel powder is ≤0.50 g / cm³. 3 .

[0028] Preferably, both inorganic binder layer A and inorganic binder layer B are formed by curing an inorganic binder; the inorganic binder is a hollow glass microsphere / silica sol composite adhesive, which comprises silica sol and hollow glass microspheres in a mass ratio of 100:(15-40); the D of the hollow glass microspheres... 50 The micrometer diameter is 30-60 μm, and the true density is ≤0.65 g / cm³. 3 .

[0029] Inorganic binder layer A and inorganic binder layer B can ensure the filling stability of the porous heat insulation and fireproof layer in galvanized steel plate and color steel plate, and ensure that the smoke exhaust duct has a good and stable fire resistance and heat insulation effect.

[0030] The present invention provides a method for preparing a fire-resistant and heat-insulating smoke exhaust duct, which is achieved through the following technical solution:

[0031] A method for preparing a fire-resistant and heat-insulating smoke exhaust duct includes the following steps:

[0032] Step 1: Preparation of a porous heat-insulating and fire-resistant layer;

[0033] Step 2: Spray the inorganic sealant onto the upper and lower surfaces of the porous heat-insulating and fire-resistant layer, with a single-sided application rate of 10-60 g / m². 2 After spraying, the material is placed at 80-120℃ for 1-4 hours to undergo dehydration and condensation reaction and cure, forming an inorganic sealing layer A on the upper surface of the porous heat-insulating and fireproof material and an inorganic sealing layer B on the lower surface of the porous heat-insulating and fireproof material.

[0034] Step 3: After coating one surface of the porous heat-insulating and fireproof layer prepared in Step 2 with an inorganic adhesive, it is wrapped around the outer wall of the galvanized steel plate. Then, the two ends of the porous heat-insulating and fireproof layer are sewn together with quartz fiber yarn. Next, an inorganic adhesive is coated on the other surface of the porous heat-insulating and fireproof layer. Finally, the assembled color steel plate is molded around the porous heat-insulating and fireproof layer to obtain a semi-finished product.

[0035] Step four: Place the semi-finished product at room temperature for 6-24 hours to cure, and the finished smoke exhaust duct will be obtained.

[0036] The preparation method of the present invention is relatively simple, easy to operate, and easy to realize industrial production.

[0037] By adopting the above technical solutions, the fire resistance and heat insulation performance of smoke exhaust ducts can be further improved.

[0038] In summary, the present invention has the following advantages:

[0039] 1. This invention uses lightweight and highly fire-resistant and heat-insulating modified aerogel insulation felt as the fire-resistant and heat-insulating filling layer of the smoke exhaust duct, giving the smoke exhaust duct excellent fire-resistant and heat-insulating performance. Moreover, its overall weight is reduced by at least 25% compared with the existing smoke exhaust duct, which facilitates the transportation, handling, assembly and construction of the smoke exhaust duct, reduces the assembly cost of the smoke exhaust system and improves the safety of fire protection facilities.

[0040] 2. The method for preparing the fire-resistant and heat-insulating smoke exhaust duct in this invention is relatively simple and easy to achieve industrial mass production. The resulting smoke exhaust duct is lightweight, which facilitates the construction of the smoke exhaust system in the later stage. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the overall structure of the fire-resistant and heat-insulating smoke exhaust duct in this invention.

[0042] Figure 2 This is a cross-sectional view of the fire-resistant and heat-insulating smoke exhaust duct of the present invention.

[0043] In the diagram, 1 is galvanized steel sheet; 2 is color steel sheet; 3 is porous heat insulation and fireproof layer; 31 is inorganic sealing layer A; 32 is inorganic sealing layer B; 4 is inorganic adhesive layer A; and 5 is inorganic adhesive layer B. Detailed Implementation

[0044] To further understand the inventiveness and technical advancements of this invention, the preferred embodiments of this invention will be discussed in detail below with reference to examples and comparative examples.

[0045] Example: Reference Figure 1 and Figure 2 A fire-resistant and heat-insulating smoke exhaust duct includes a galvanized steel sheet 1, a color steel sheet 2, and a porous heat-insulating and fireproof layer 3 fixedly connected between the galvanized steel sheet 1 and the color steel sheet 2. An inorganic sealing layer A31 is formed on the upper surface of the porous heat-insulating and fireproof layer 3. An inorganic sealing layer B32 is formed on the lower surface of the porous heat-insulating and fireproof layer 3. The inorganic sealing layer A31 is fixedly connected to the inner wall of the color steel sheet 2 by an inorganic adhesive layer A4. The inorganic sealing layer B32 is fixedly connected to the inner wall of the galvanized steel sheet 1 by an inorganic adhesive layer B5.

[0046] The porous heat insulation and fireproof layer 3 is an aerogel insulation felt or a porous ceramic / aerogel composite insulation felt.

[0047] Both inorganic plugging layer A31 and inorganic plugging layer B32 are formed by the curing of inorganic plugging agent.

[0048] The inorganic plugging agent is made of a metal oxide composite sol system and a low-density insulating filler. The low-density insulating filler is at least one of hollow glass microspheres and aerogel powder. The true density of the hollow glass microspheres is ≤0.65 g / cm³. 3 The true density of aerogel powder is ≤0.50 g / cm³. 3 .

[0049] The content of low-density insulating filler in the inorganic plugging agent is 5-50 wt%. The metal oxide composite sol system is an aluminum hydroxide / silica composite sol prepared by the sol-gel method. Alternatively, the metal oxide composite sol system is a titanium dioxide / silica composite sol prepared by the sol-gel method.

[0050] Both inorganic adhesive layer A4 and inorganic adhesive layer B5 are formed by curing inorganic adhesive.

[0051] The inorganic binder is a composite adhesive for insulating glass microspheres / silica sol. This composite adhesive comprises silica sol and insulating glass microspheres at a mass ratio of 100:(15-40). The D of the insulating glass microspheres... 50 The micrometer diameter is 30-60 μm, and the true density is ≤0.65 g / cm³. 3 .

[0052] The porous heat-insulating and fireproof layer 3 is a porous heat-insulating and fireproof material.

[0053] A method for preparing porous heat-insulating and fire-resistant materials includes the following steps:

[0054] Step 1: Surface grafting modification treatment is performed on the porous thermal insulation substrate, specifically as follows: The porous thermal insulation substrate is immersed in a 0.5-5 wt% aqueous solution of methacryloyloxysilane in ethanol for 5-60 minutes with stirring. After immersion, it is removed and dried to obtain the porous thermal insulation substrate with surface grafting modification of methacryloyloxysilane. Preferably, the porous thermal insulation substrate is an aerogel insulation felt, and the thickness of the aerogel insulation felt is 2 mm, 3 mm, 5 mm, 6 mm, 9 mm, or 10 mm. The porous thermal insulation substrate is selected from any one of the following: thermal insulation felt FMD450, thermal insulation felt FMB350, thermal insulation felt FMB400, thermal insulation felt FMC200, thermal insulation felt FMA400, and thermal insulation felt FMA650.

[0055] Meanwhile, the layered two-dimensional nanofiller is subjected to surface grafting modification treatment as follows: The layered two-dimensional nanofiller is immersed in a 0.5-5wt% mercaptosilane ethanol aqueous solution, stirred for 5-60 minutes, then removed and dried to obtain the layered two-dimensional nanofiller with surface grafted mercaptosilane.

[0056] Step 2: Disperse the surface-grafted modified layered two-dimensional nanofillers in a solvent to obtain a pre-impregnation dispersion system;

[0057] Preferably, in step two, the surface-grafted modified layered two-dimensional nanofiller is dispersed in supercritical carbon dioxide to obtain a pre-impregnation dispersion system, wherein the temperature of the supercritical carbon dioxide is 40-45℃ and the pressure is 10-15MPa.

[0058] Step 3: Immerse the surface-modified porous thermal insulation substrate in the prepreg dispersion system of Step 2, keep it at 40-45℃ for 30-60 minutes, remove the solvent, so that the layered two-dimensional nanofiller is uniformly loaded inside the aerogel thermal insulation felt to obtain a semi-finished porous thermal insulation and fireproof material.

[0059] Step four: Place the semi-finished porous heat-insulating and fire-resistant material at 80-140℃ for 0.5-2 hours to obtain the finished porous heat-insulating and fire-resistant material.

[0060] A method for preparing a fire-resistant and heat-insulating smoke exhaust duct includes the following steps:

[0061] Step 1, Preparation of porous heat-insulating and fire-resistant layer 3, see Preparation of porous heat-insulating and fire-resistant materials for details;

[0062] Preferably, the porous heat-insulating and fireproof material needs to undergo surface hydrophilic modification treatment: the upper and lower surfaces of the porous heat-insulating and fireproof material are subjected to low-temperature plasma treatment, with compressed air as the gas source of the low-temperature plasma generator, and the treatment time is 15-30s, to obtain the hydrophilic modified porous heat-insulating and fireproof material.

[0063] Step 2: Spray the inorganic sealant onto the upper and lower surfaces of the hydrophilically modified porous thermal insulation and fireproof material. The amount of inorganic sealant applied to each surface is 10-60 g / m². 2 After spraying, the material is placed at 80-120℃ for 1-4 hours for dehydration and condensation reaction to form an inorganic sealing layer A31 on the upper surface of the porous heat-insulating and fireproof material and an inorganic sealing layer B32 on the lower surface of the porous heat-insulating and fireproof material.

[0064] Step 3: After coating the surface of the porous heat-insulating and fireproof layer 3 prepared in Step 2 with an inorganic binder, it is wrapped around the outer wall of the galvanized steel plate 1. The amount of inorganic binder used is 30-90 g / m². 2 Subsequently, quartz fiber yarn was used to sew the two ends of the porous heat-insulating fireproof layer 3 together. Then, an inorganic adhesive was applied to the other surface of the porous heat-insulating fireproof layer 3, with the amount of inorganic adhesive being 30-90 g / m². 2 Finally, the prefabricated color steel plate 2 is molded onto the outer periphery of the porous heat insulation and fireproof layer 3 to obtain a semi-finished product;

[0065] Step four: Place the semi-finished product at room temperature for 6-24 hours to cure, and the finished smoke exhaust duct will be obtained.

[0066] Example 1: A method for preparing porous heat-insulating and fire-resistant materials, comprising the following steps:

[0067] Step 1: Surface grafting modification treatment is performed on the thermal insulation felt FMB350, as follows: The thermal insulation felt FMB350 is immersed in a 2.0wt% KH570 ethanol aqueous solution with an alcohol-to-water weight ratio of 9:1. The cutting size of the thermal insulation felt FMB350 is 400mm*500mm*3mm. The solution is immersed for 30 minutes with stirring at 200rpm. After immersion, it is removed and dried to obtain a porous thermal insulation substrate with surface grafting modification of KH570.

[0068] Meanwhile, the boron nitride nanosheets were subjected to surface grafting modification treatment as follows: the boron nitride nanosheets were immersed in a 2.0 wt% KH591 aqueous solution for 30 min with stirring, and then removed and dried to obtain boron nitride nanosheets with KH591 grafted on the surface.

[0069] Step 2: 6.0g of boron nitride nanosheets grafted with KH591 were dispersed in 1.6kg of supercritical carbon dioxide to obtain a pre-impregnated dispersion system. The temperature of the supercritical carbon dioxide was 45℃ and the pressure was 10MPa.

[0070] Step 3: The porous thermal insulation substrate with KH570 surface grafting modification is loaded into the molding mold. The molding mold has a size of 400mm*500mm*10mm. The molding mold filled with the porous thermal insulation substrate with KH570 surface grafting modification is placed in the reactor. The pressure is adjusted to 10MPa. The pre-impregnation dispersion system immersed in Step 2 is pumped into the molding mold in the reactor. The mixture is kept at 45℃ for 60min. The pressure is reduced to atmospheric pressure to remove the supercritical carbon dioxide solvent. The mixture is then naturally cooled to room temperature, so that the boron nitride nanosheets are uniformly loaded inside the aerogel insulation felt to obtain a semi-finished porous thermal insulation and fireproof material.

[0071] Step 4: Place the semi-finished porous heat insulation and fireproof material at 120℃ for 1 hour to obtain the finished porous heat insulation and fireproof material with a boron nitride nanosheet loading rate of 5.0wt%.

[0072] KH570, γ-methacryloyloxypropyltrimethoxysilane, CAS No. 2530-85-0. KH591, γ-mercaptopropyltrimethoxysilane, CAS No. 4420-74-0. Boron nitride nanosheets, hexagonal boron nitride nanosheets XT-BN-01, average particle size 120 nm, Shanghai Xiangtian Nanomaterials Co., Ltd.

[0073] A method for preparing a fire-resistant and heat-insulating smoke exhaust duct includes the following steps:

[0074] Step 1, Preparation of porous heat-insulating and fire-resistant layer 3, see Preparation of porous heat-insulating and fire-resistant materials for details;

[0075] Surface hydrophilic modification treatment of porous heat-insulating and fireproof materials: Low-temperature plasma treatment is performed on the upper and lower surfaces of the porous heat-insulating and fireproof materials. Compressed air is used as the gas source of the low-temperature plasma generator. The temperature is set to 4℃ and the treatment time is set to 30s to obtain the hydrophilic modified porous heat-insulating and fireproof materials.

[0076] Step two, add 25g of hollow glass microspheres (3M hollow glass microspheres VS5500, true density 0.38g / cm³). 3 An inorganic sealant is prepared by uniformly mixing 60g of silica sol (nano silica transparent liquid VK-SO1B, Zhejiang Zhitai Nano Micro New Materials Co., Ltd.) and 15g of titanium sol (nano titanium sol HN-TA33, Hangzhou Hengna New Materials Co., Ltd.). The inorganic sealant is then sprayed onto the upper and lower surfaces of the hydrophilically modified porous thermal insulation and fireproof material. The spraying amount of inorganic sealant on one side is 15g / m². 2 After spraying, the material is placed at 80℃ for 4 hours to undergo dehydration and condensation reaction and cure, forming an inorganic sealing layer A31 on the upper surface of the porous heat-insulating and fireproof material and an inorganic sealing layer B32 on the lower surface of the porous heat-insulating and fireproof material.

[0077] Step 3: Add 20g of hollow glass microspheres (3M hollow glass microspheres VS5500, true density 0.38g / cm³). 3 The inorganic binder is obtained by uniformly mixing 80g of silica sol (nano-silica transparent liquid VK-SO1B, Zhejiang Zhitai Nano-Micro New Materials Co., Ltd.) with 80g of silica sol (nano-silica transparent liquid VK-SO1B, Zhejiang Zhitai Nano-Micro New Materials Co., Ltd.). The porous heat-insulating and fireproof layer 3 prepared in step two is coated with the inorganic binder and then wrapped around the outer wall of the galvanized steel plate 1. The amount of inorganic binder used is 30g / m². 2 Subsequently, 95tex quartz fiber yarn SJ101 was used to sew the two ends of the porous heat-insulating fireproof layer 3. Then, an inorganic adhesive was applied to the other surface of the porous heat-insulating fireproof layer 3, with an amount of 30g / m². 2 Finally, the prefabricated color steel plate 2 is molded onto the outer periphery of the porous heat insulation and fireproof layer 3 to obtain a semi-finished product;

[0078] Step four: Place the semi-finished product at room temperature for 24 hours to cure, and the finished smoke exhaust duct will be obtained.

[0079] The quartz fiber yarn SJ101 was supplied by Henan Shenjiu Tianhang New Material Co., Ltd.

[0080] The difference between Example 2 and Example 1 lies in the preparation method of the porous thermal insulation and fireproof material: In step two, 4.0 g of boron nitride nanosheets grafted with KH591 were dispersed in 1.6 kg of supercritical carbon dioxide to obtain a pre-impregnation dispersion system. The temperature of the supercritical carbon dioxide was 45°C and the pressure was 10 MPa. The remaining steps were the same. The boron nitride nanosheet loading rate in the finished porous thermal insulation and fireproof material was 3.4 wt%.

[0081] The difference between Example 3 and Example 1 lies in the preparation method of the porous thermal insulation and fireproof material: In step two, 8.0 g of boron nitride nanosheets grafted with KH591 were dispersed in 1.6 kg of supercritical carbon dioxide to obtain a pre-impregnation dispersion system. The temperature of the supercritical carbon dioxide was 45°C, and the pressure was 10 MPa. The remaining steps were the same. The boron nitride nanosheet loading rate in the finished porous thermal insulation and fireproof material was 6.7 wt%.

[0082] Comparative Example 1: The porous heat insulation and fireproof material is heat insulation felt FMB350, and the cutting size of heat insulation felt FMB350 is 400mm*500mm*3mm.

[0083] The difference between Comparative Example 2 and Example 1 lies in the preparation method of the porous thermal insulation and fireproof material: In step two, 1.0 g of boron nitride nanosheets grafted with KH591 were dispersed in 1.6 kg of supercritical carbon dioxide to obtain a pre-impregnation dispersion system. The temperature of the supercritical carbon dioxide was 45°C and the pressure was 10 MPa. The remaining steps were the same. The boron nitride nanosheet loading rate in the finished porous thermal insulation and fireproof material was 0.8 wt%.

[0084] The preparation of test sample 1 is as follows: S1. Surface hydrophilic modification treatment of the porous heat-insulating and fire-retardant material prepared in Example 1: Low-temperature plasma treatment was performed on the upper and lower surfaces of the porous heat-insulating and fire-retardant material. Compressed air was used as the gas source of the low-temperature plasma generator, the temperature was set to 4℃, and the treatment time was set to 30s, resulting in a hydrophilic modified porous heat-insulating and fire-retardant material; S2. 25g of hollow glass microspheres (3M hollow glass microspheres VS5500, true density 0.38g / cm³) were added. 3 An inorganic sealant is prepared by uniformly mixing 60g of silica sol (nano silica transparent liquid VK-SO1B, Zhejiang Zhitai Nano Micro New Materials Co., Ltd.) and 15g of titanium sol (nano titanium sol HN-TA33, Hangzhou Hengna New Materials Co., Ltd.). The inorganic sealant is then sprayed onto the upper and lower surfaces of the hydrophilically modified porous thermal insulation and fireproof material. The spraying amount of inorganic sealant on one side is 15g / m². 2After spraying, the material is placed at 80℃ for 4 hours for dehydration and condensation reaction to cure, forming an inorganic sealing layer A on the upper surface of the porous heat-insulating and fire-resistant material and an inorganic sealing layer B on the lower surface of the porous heat-insulating and fire-resistant material; S3, 20g of hollow glass microspheres (3M hollow glass microspheres VS5500, true density 0.38g / cm³) are added. 3 The inorganic binder is obtained by uniformly mixing 80g of silica sol (nano-silica transparent liquid VK-SO1B, Zhejiang Zhitai Nano-Micro New Materials Co., Ltd.). A release film is then coated onto the surface of a porous heat-insulating and fire-resistant layer 3, which contains inorganic sealing layers A and B. The amount of inorganic binder used is 30g / m³. 2 Then, an inorganic binder is coated onto the other surface of the porous heat-insulating and fireproof layer 3, and a release film is laminated on it. The amount of inorganic binder used is 30g / m². 2 A 5kg steel plate is placed on the top release film and cured at room temperature for 24 hours to obtain test sample 1.

[0085] The difference between test sample 2 and test sample 1 is that test sample 2 uses the porous heat-insulating and fire-resistant material prepared in Example 2. The difference between test sample 3 and test sample 1 is that test sample 3 uses the porous heat-insulating and fire-resistant material prepared in Example 3. The difference between test sample 4 and test sample 1 is that test sample 4 uses FMB350 insulation felt as the porous heat-insulating and fire-resistant material in test sample 4. The difference between test sample 5 and test sample 1 is that test sample 5 uses the porous heat-insulating and fire-resistant material prepared in Comparative Example 2 in test sample 5.

[0086] Table 1 shows the performance parameters of the porous heat-insulating and fire-resistant materials in test samples 1-5.

[0087]

[0088] As shown in Table 1, the porous heat-insulating and fire-resistant materials in Examples 1-3, with a diameter of 3.0 ± 0.05 mm, increased their fire resistance limit from 0.5 h to 1.0 h, and their density was 0.26-0.27 g / cm³. 3 With a thermal conductivity of 0.03-0.04 W / (m·K), it can ensure the fire resistance and heat insulation performance of the smoke exhaust duct while reducing the overall weight of the smoke exhaust duct, realizing a lightweight design, which facilitates the transportation, handling, assembly and construction of the smoke exhaust duct, and reduces the assembly cost of the smoke exhaust system.

[0089] The difference between Example 4 and Example 1 lies in the preparation method of the porous heat-insulating and fire-retardant material, as follows:

[0090] Step 1: Perform surface grafting modification treatment on the thermal insulation felt FMB350, as follows: Immerse the thermal insulation felt FMB350 in a 2.0wt% KH570 ethanol aqueous solution (ethanol-water weight ratio of 9 / 1). The cutting size of the thermal insulation felt FMB350 is 400mm*500mm*2mm. Immerse for 30 minutes with stirring at 200rpm, then remove and dry to obtain a porous thermal insulation substrate with KH570 surface grafting modification treatment.

[0091] Meanwhile, the boron nitride nanosheets were subjected to surface grafting modification treatment as follows: the boron nitride nanosheets were immersed in a 2.0 wt% KH591 aqueous solution for 30 min with stirring, and then removed and dried to obtain boron nitride nanosheets with KH591 grafted on the surface.

[0092] Step 2: 4.0g of boron nitride nanosheets grafted with KH591 were dispersed in 1.6kg of supercritical carbon dioxide to obtain a pre-impregnation dispersion system. The temperature of the supercritical carbon dioxide was 45℃ and the pressure was 10MPa.

[0093] Step 3: The porous thermal insulation substrate with KH570 surface grafting modification is loaded into the molding mold. The molding mold has a size of 400mm*500mm*10mm. The molding mold filled with the porous thermal insulation substrate with KH570 surface grafting modification is placed in the reactor. The pressure is adjusted to 10MPa. The molding mold immersed in the pre-impregnation dispersion system in Step 2 is pumped into the reactor. The mixture is kept at 45℃ for 60min. The pressure is reduced to atmospheric pressure to remove the supercritical carbon dioxide solvent. The mixture is then naturally cooled to room temperature, so that the boron nitride nanosheets are uniformly loaded inside the aerogel insulation felt to obtain a semi-finished porous thermal insulation and fireproof material.

[0094] Step 4: Place the semi-finished porous heat insulation and fireproof material at 120℃ for 1 hour to obtain the finished porous heat insulation and fireproof material with a boron nitride nanosheet loading rate of 5.0wt%.

[0095] The difference between Example 5 and Example 4 is that in step two, 6.0 g of boron nitride nanosheets grafted with KH591 were dispersed in 1.6 kg of supercritical carbon dioxide (45℃ / 10 MPa) to obtain a pre-impregnation dispersion system. The boron nitride nanosheet loading rate in the finished porous thermal insulation and fireproof material was 7.4 wt%.

[0096] The difference between Comparative Example 3 and Example 4 is that the porous heat insulation and fireproof material is heat insulation felt FMB350, and the cutting size of heat insulation felt FMB350 is 400mm*500mm*2mm.

[0097] The difference between Comparative Example 4 and Example 4 is that in step two, 2.0 g of boron nitride nanosheets grafted with KH591 were dispersed in 1.6 kg of supercritical carbon dioxide (45℃ / 10 MPa) to obtain a pre-impregnation dispersion system. The boron nitride nanosheet loading rate in the finished porous thermal insulation and fireproof material was 3.1 wt%.

[0098] The difference between test sample 6 and test sample 1 is that test sample 6 uses the porous heat-insulating and fire-resistant material prepared in Example 4. The difference between test sample 7 and test sample 1 is that test sample 7 uses the porous heat-insulating and fire-resistant material prepared in Example 5. The difference between test sample 8 and test sample 1 is that test sample 8 uses FMB350 insulation felt, a porous heat-insulating and fire-resistant material, with a cut size of 400mm*500mm*2mm. The difference between test sample 9 and test sample 1 is that test sample 9 uses the porous heat-insulating and fire-resistant material prepared in Comparative Example 4.

[0099] Table 2 shows the performance parameters of the porous heat-insulating and fire-resistant materials in test samples 6-9.

[0100]

[0101] As shown in Table 2, the porous heat-insulating and fire-resistant materials in Examples 4-5, with a specification of 2.0±0.05mm, improved their fire resistance rating from <0.5h to 0.5h, meeting the national standard GB / T 51251-2017 which stipulates that the fire resistance rating of smoke exhaust ducts should be ≥0.5h, and the density is 0.26-0.275g / cm³. 3 With a thermal conductivity of 0.03-0.045 W / (m·K), it can ensure the fire resistance and heat insulation performance of the smoke exhaust duct while further reducing the overall weight of the smoke exhaust duct.

[0102] The difference between Comparative Example 5 and Example 1 is that in step two of the preparation method of a fire-resistant and heat-insulating smoke exhaust duct, 60g of silica sol (nano-silica transparent liquid VK-SO1B, Zhejiang Zhitai Nano-Micro New Materials Co., Ltd.) and 15g of titanium sol (nano-titanium sol HN-TA33, Hangzhou Hengna New Materials Co., Ltd.) are mixed evenly to obtain an inorganic sealing agent. The inorganic sealing agent is then sprayed onto the upper and lower surfaces of the hydrophilically modified porous heat-insulating and fireproof material, with a single-sided spraying amount of 15g / m. 2After spraying, the material is placed at 80℃ for 4 hours for dehydration and condensation reaction to cure, forming an inorganic sealing layer A31 on the upper surface of the porous heat-insulating and fireproof material and an inorganic sealing layer B32 on the lower surface of the porous heat-insulating and fireproof material. In step three, silica sol (nano-silica transparent liquid VK-SO1B, Zhejiang Zhitai Nano-Micro New Materials Co., Ltd.) is used as an inorganic binder. After coating the surface of the porous heat-insulating and fireproof layer 3 prepared in step two with the inorganic binder, it is then wrapped around the outer wall of the galvanized steel plate 1. The amount of inorganic binder used is 30 g / m². 2 Subsequently, 95Tex quartz fiber yarn SJ101 was used to sew the two ends of the porous heat-insulating fireproof layer 3. Then, an inorganic adhesive was applied to the other surface of the porous heat-insulating fireproof layer 3, with an amount of 30g / m². 2 Finally, the prefabricated color steel plate 2 is molded onto the outer periphery of the porous heat-insulating and fireproof layer 3 to obtain a semi-finished product. The remaining steps are the same.

[0103] The difference between Comparative Example 6 and Example 4 is that in step two of the preparation method of a fire-resistant and heat-insulating smoke exhaust duct, 60g of silica sol (nano-silica transparent liquid VK-SO1B, Zhejiang Zhitai Nano-Micro New Materials Co., Ltd.) and 15g of titanium sol (nano-titanium sol HN-TA33, Hangzhou Hengna New Materials Co., Ltd.) are mixed evenly to obtain an inorganic sealing agent. The inorganic sealing agent is then sprayed onto the upper and lower surfaces of the hydrophilically modified porous heat-insulating fireproof material, with a single-sided spraying amount of 15g / m. 2 After spraying, the material is placed at 80℃ for 4 hours for dehydration and condensation reaction to cure, forming an inorganic sealing layer A31 on the upper surface of the porous heat-insulating and fireproof material and an inorganic sealing layer B32 on the lower surface of the porous heat-insulating and fireproof material. In step three, silica sol (nano-silica transparent liquid VK-SO1B, Zhejiang Zhitai Nano-Micro New Materials Co., Ltd.) is used as an inorganic binder. After coating the surface of the porous heat-insulating and fireproof layer 3 prepared in step two with the inorganic binder, it is then wrapped around the outer wall of the galvanized steel plate 1. The amount of inorganic binder used is 30 g / m². 2 Subsequently, 95tex quartz fiber yarn SJ101 was used to sew the two ends of the porous heat-insulating fireproof layer 3. Then, an inorganic adhesive was applied to the other surface of the porous heat-insulating fireproof layer 3, with an amount of 30g / m². 2 Finally, the prefabricated color steel plate 2 is molded onto the outer periphery of the porous heat-insulating and fireproof layer 3 to obtain a semi-finished product. The remaining steps are the same.

[0104] The difference between test sample 10 and test sample 1 is as follows: S1. The porous heat-insulating and fireproof material prepared in Comparative Example 5 is subjected to surface hydrophilic modification treatment: the upper and lower surfaces of the porous heat-insulating and fireproof material are subjected to low-temperature plasma treatment, compressed air is used as the gas source of the low-temperature plasma generator, the temperature is set to 4℃, and the treatment time is set to 30s, to obtain the hydrophilic modified porous heat-insulating and fireproof material; S2. 60g of silica sol (nano silica transparent liquid VK-SO1B, Zhejiang Zhitai Nano Micro New Materials Co., Ltd.) and 15g of titanium sol (nano titanium sol HN-TA33, Hangzhou Hengna New Materials Co., Ltd.) are mixed evenly to obtain an inorganic sealing agent, and the inorganic sealing agent is sprayed on the upper and lower surfaces of the hydrophilic modified porous heat-insulating and fireproof material respectively, with a single-sided inorganic sealing agent spraying amount of 15g / m 2 After spraying, the material is placed at 80℃ for 4 hours for dehydration and condensation reaction to cure, forming an inorganic sealing layer A on the upper surface of the porous heat-insulating and fireproof material and an inorganic sealing layer B on the lower surface of the porous heat-insulating and fireproof material; S3, using silica sol (nano-silica transparent liquid VK-SO1B, Zhejiang Zhitai Nano-Micro New Materials Co., Ltd.) as an inorganic binder, the porous heat-insulating and fireproof layer 3, which is composited with inorganic sealing layer A and inorganic sealing layer B, is coated with an inorganic binder and then laminated with a release film. The amount of inorganic binder is 30g / m³. 2 Then, an inorganic binder is coated onto the other surface of the porous heat-insulating and fireproof layer 3, and a release film is laminated on it. The amount of inorganic binder used is 30g / m². 2 A 5kg steel plate is placed on the top release film, and the test sample 10 is obtained by curing at room temperature for 24 hours.

[0105] The difference between test sample 11 and test sample 1 is as follows: S1. The porous heat-insulating and fireproof material prepared in Comparative Example 6 is subjected to surface hydrophilic modification treatment: the upper and lower surfaces of the porous heat-insulating and fireproof material are subjected to low-temperature plasma treatment, compressed air is used as the gas source of the low-temperature plasma generator, the temperature is set to 4℃, and the treatment time is set to 30s, to obtain the hydrophilic modified porous heat-insulating and fireproof material; S2. 60g of silica sol (nano silica transparent liquid VK-SO1B, Zhejiang Zhitai Nano Micro New Materials Co., Ltd.) and 15g of titanium sol (nano titanium sol HN-TA33, Hangzhou Hengna New Materials Co., Ltd.) are mixed evenly to obtain an inorganic sealing agent, and the inorganic sealing agent is sprayed on the upper and lower surfaces of the hydrophilic modified porous heat-insulating and fireproof material respectively, with a single-sided inorganic sealing agent spraying amount of 15g / m 2After spraying, the material is placed at 80℃ for 4 hours for dehydration and condensation reaction to cure, forming an inorganic sealing layer A on the upper surface of the porous heat-insulating and fireproof material and an inorganic sealing layer B on the lower surface of the porous heat-insulating and fireproof material; S3, using silica sol (nano-silica transparent liquid VK-SO1B, Zhejiang Zhitai Nano-Micro New Materials Co., Ltd.) as an inorganic binder, the porous heat-insulating and fireproof layer 3, which is composited with inorganic sealing layer A and inorganic sealing layer B, is coated with an inorganic binder and then laminated with a release film. The amount of inorganic binder is 30g / m³. 2 Then, an inorganic binder is coated onto the other surface of the porous heat-insulating and fireproof layer 3, and a release film is laminated on it. The amount of inorganic binder used is 30g / m². 2 A 5kg steel plate is placed on the top release film and cured at room temperature for 24 hours to obtain test sample 11.

[0106] Table 3 shows the performance parameters of the porous heat-insulating and fire-resistant materials in test samples 1, 6, and 10-11.

[0107]

[0108] As shown in Table 3, adding hollow glass microspheres to inorganic binders and inorganic sealants helps to reduce the thermal conductivity of porous heat-insulating and fire-resistant materials, making their thermal conductivity <0.035W / (m·K), thus giving them better fire-resistant and heat-insulating properties.

[0109] This invention uses a lightweight and highly fire-resistant and heat-insulating modified aerogel insulation felt as the fire-resistant and heat-insulating filling layer of the smoke exhaust duct, giving the smoke exhaust duct excellent fire-resistant and heat-insulating performance. Moreover, its overall weight is reduced by at least 25% compared with existing smoke exhaust ducts, which facilitates the transportation, handling, assembly and construction of the smoke exhaust duct, reduces the assembly cost of the smoke exhaust system and improves the safety of fire protection facilities.

[0110] It should be noted that this specific embodiment is merely an explanation of the technical solution of the present invention and is not intended to limit the present invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but as long as they are within the scope of the claims of the present invention, they are protected by patent law.

Claims

1. A fire-resistant and heat-insulating smoke exhaust duct, characterized in that: The material includes a galvanized steel sheet (1), a color steel sheet (2), and a porous heat-insulating and fireproof layer (3) fixedly connected between the galvanized steel sheet (1) and the color steel sheet (2); an inorganic sealing layer A (31) is formed on the upper surface of the porous heat-insulating and fireproof layer (3); an inorganic sealing layer B (32) is formed on the lower surface of the porous heat-insulating and fireproof layer (3); the inorganic sealing layer A (31) is fixedly connected to the inner wall of the color steel sheet (2) through an inorganic adhesive layer A (4); the inorganic sealing layer B (32) is fixedly connected to the inner wall of the galvanized steel sheet (1) through an inorganic adhesive layer B (5); The porous heat-insulating and fireproof layer (3) is a porous heat-insulating and fireproof material. The preparation method of the porous heat-insulating and fireproof material includes the following steps: Step 1: Perform surface grafting modification treatment on the porous thermal insulation substrate; Simultaneously, the layered two-dimensional nanofiller was subjected to surface grafting modification treatment; Step 2: Disperse the surface-grafted modified layered two-dimensional nanofiller in a solvent to obtain a pre-impregnation dispersion system; Step 3: Immerse the surface-modified porous thermal insulation substrate in the prepreg dispersion system of Step 2, keep it at 40-45℃ for 30-60 minutes, remove the solvent, so that the layered two-dimensional nanofiller is uniformly loaded inside the aerogel thermal insulation felt to obtain a semi-finished porous thermal insulation and fireproof material. Step 4: Place the semi-finished porous heat-insulating and fire-resistant material at 80-140℃ for 0.5-2 hours to obtain the finished porous heat-insulating and fire-resistant material; Step one involves surface grafting modification of the porous thermal insulation substrate, specifically as follows: The porous thermal insulation substrate is immersed in a 0.5-5 wt% aqueous solution of methacryloyloxysilane in ethanol, stirred for 5-60 minutes, then removed and dried to obtain the porous thermal insulation substrate with surface grafting methacryloyloxysilane modification. The surface grafting modification of the layered two-dimensional nanofiller is specifically as follows: The layered two-dimensional nanofiller is immersed in a 0.5-5 wt% aqueous solution of mercaptosilane in ethanol, stirred for 5-60 minutes, then removed and dried to obtain the layered two-dimensional nanofiller with surface grafting mercaptosilane. Both the inorganic plugging layer A (31) and the inorganic plugging layer B (32) are formed by curing an inorganic plugging agent; the inorganic plugging agent is made of a metal oxide composite sol system and a low-density thermal insulation filler; the low-density thermal insulation filler is at least one of hollow glass microspheres and aerogel powder; the true density of the hollow glass microspheres is ≤0.65g / cm³. 3 The true density of the aerogel powder is ≤0.50 g / cm³. 3 The content of low-density thermal insulation filler in the inorganic plugging agent is 5-50 wt%; the metal oxide composite sol system is an aluminum hydroxide / silica composite sol prepared by the sol-gel method; or the metal oxide composite sol system is a titanium dioxide / silica composite sol prepared by the sol-gel method.

2. The fire-resistant and heat-insulating smoke exhaust duct according to claim 1, characterized in that: The porous thermal insulation substrate in step one is an aerogel insulation felt, and the thickness of the aerogel insulation felt is 2mm, 3mm, 5mm, 6mm, 9mm, or 10mm.

3. The fire-resistant and heat-insulating smoke exhaust duct according to claim 1, characterized in that: The porous thermal insulation substrate is selected from any one of thermal insulation felt FMD450, thermal insulation felt FMB350, thermal insulation felt FMB400, thermal insulation felt FMC200, thermal insulation felt FMA400, and thermal insulation felt FMA650.

4. The fire-resistant and heat-insulating smoke exhaust duct according to claim 1, characterized in that: The layered two-dimensional nanofiller is one or more of boron nitride, molybdenum disulfide, and tungsten disulfide.

5. The fire-resistant and heat-insulating smoke exhaust duct according to claim 1, characterized in that: In step two, the surface-grafted modified layered two-dimensional nanofiller is dispersed in supercritical carbon dioxide to obtain a pre-impregnation dispersion system. The temperature of the supercritical carbon dioxide is 40-45℃ and the pressure is 10-15MPa.

6. The fire-resistant and heat-insulating smoke exhaust duct according to claim 1, characterized in that: Both inorganic binder layer A (4) and inorganic binder layer B (5) are formed by curing inorganic binder; the inorganic binder is a hollow glass microsphere / silica sol composite adhesive, which is made of silica sol and hollow glass microspheres in a mass ratio of 100:(15-40); the D of the hollow glass microspheres 50 The micrometer diameter is 30-60 μm, and the true density is ≤0.65 g / cm³. 3 .

7. A method for preparing a fire-resistant and heat-insulating smoke exhaust duct according to any one of claims 1-6, characterized in that: Includes the following steps: Step 1, Preparation of porous heat-insulating and fire-resistant layer (3); Step 2: Apply the inorganic sealant to the upper and lower surfaces of the porous heat-insulating and fireproof layer (3), with a single-sided application rate of 10-60 g / m². 2 After spraying, the material is placed at 80-120℃ for 1-4 hours to undergo dehydration and condensation reaction to form an inorganic sealing layer A (31) on the upper surface of the porous heat-insulating and fireproof material and an inorganic sealing layer B (32) on the lower surface of the porous heat-insulating and fireproof material. Step 3: After coating one surface of the porous heat-insulating and fireproof layer (3) prepared in step 2 with an inorganic adhesive, it is wrapped around the outer wall of the galvanized steel plate (1). Then, the two ends of the porous heat-insulating and fireproof layer (3) are sewn together with quartz fiber yarn. Then, the inorganic adhesive is coated on the other surface of the porous heat-insulating and fireproof layer (3). Finally, the assembled color steel plate (2) is molded onto the outer periphery of the porous heat-insulating and fireproof layer (3) to obtain a semi-finished product. Step four: Place the semi-finished product at room temperature for 6-24 hours to cure, and the finished smoke exhaust duct will be obtained.

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