Inorganic aerogel thermal insulation and sound insulation composite air duct and its application

Abstract

The present invention relates to an inorganic aerogel thermal insulation and sound insulation composite air duct and its application. The composite air duct is composed of a plurality of continuous rectangular thermal insulation and sound insulation air duct units assembled in sequence; the pipe wall of the rectangular thermal insulation and sound insulation air duct unit is a layered structure, which is an inner layer, an aerogel thermal insulation layer, an aerogel sound insulation layer and an outer protective layer from the inside to the outside; the aerogel thermal insulation layer and the aerogel sound insulation layer are both composed of an aerogel matrix and a fiber reinforcement; in the aerogel thermal insulation layer, the aerogel matrix accounts for 20-40wt% of the total mass, and the average fiber diameter of the fiber reinforcement is 1-5.5μm; in the aerogel sound insulation layer, the aerogel matrix accounts for 10-25wt% of the total mass, and the average fiber diameter of the fiber reinforcement is 1-8.5μm. Compared with the prior art, the inorganic aerogel thermal insulation and sound insulation composite air duct of the present invention can reduce and lower the resonance and noise caused by the operation of the air duct while realizing the functions of heat insulation and cold preservation.

Description

Technical Field

[0001] The invention belongs to the technical field of ventilation ducts, and in particular relates to an inorganic aerogel heat-insulating and sound-insulating composite air duct and application thereof. Background Art

[0002] The noise generated when the air conditioning ventilation pipe is running is in the range of 50-79dB, which is transmitted through the air supply pipe and forms indoor noise. The prefabricated air duct used for the ventilation duct will generate resonance and transmission noise during the air supply process. The existing practice is to absorb and reduce noise by adding a rubber and plastic insulation layer; or to reduce the vibration of the air duct by using a shock absorber and a rubber pad to reduce the noise during use.

[0003] However, the rubber and plastic materials currently used are prone to aging, causing physical degradation such as cracking or hardening, and the thermal insulation performance will drop sharply. At the same time, it is a flammable material. After adding flame retardants, it will still burn as long as it is not away from the fire source. In addition, in addition to spreading flames and causing fires, rubber and plastic materials are also prone to produce melt drops and toxic gases. If the smoke concentration does not meet the standard, it will seriously harm people's health.

[0004] Another type of composite air duct installed inside a building uses a special material combination, such as glass fiber reinforced magnesium oxychloride cement panels, which makes the composite air duct perform well in terms of heat preservation and sound absorption, effectively reducing noise. However, inorganic magnesium steel materials are very heavy and thick. Long-term use of the material will cause brittleness, resulting in a decrease in thermal insulation effect, which will affect the energy consumption of the ship. Moreover, it can only be dismantled destructively, which is difficult and takes a long time.

[0005] Therefore, a new lightweight composite air duct with both sound insulation and heat insulation performance is still to be developed. Summary of the invention

[0006] The purpose of the present invention is to provide an inorganic aerogel thermal insulation and sound insulation composite air duct and its application in order to overcome the defects of the existing air duct that it cannot take into account the heat insulation, sound insulation and lightness characteristics.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] The present invention provides an inorganic aerogel heat-insulating and sound-insulating composite air duct, wherein the composite air duct is composed of a plurality of continuous rectangular heat-insulating and sound-insulating air duct units assembled in sequence; the pipe wall of the rectangular heat-insulating and sound-insulating air duct unit is a layered structure, which comprises an inner layer, an aerogel heat-insulating layer, an aerogel sound-insulating layer and an outer protective layer from the inside to the outside;

[0009] The inner layer and the outer protective layer are independently selected from one of galvanized sheet or galvanized sheet;

[0010] The aerogel heat insulation layer and the aerogel sound insulation layer are both composed of an aerogel matrix and a fiber reinforcement;

[0011] In the aerogel thermal insulation layer, the aerogel matrix accounts for 20-40wt% of the total mass, and the average fiber diameter of the fiber reinforcement is 1-5.5μm; in the aerogel sound insulation layer, the aerogel matrix accounts for 10-25wt% of the total mass, and the average fiber diameter of the fiber reinforcement is 1-8.5μm;

[0012] The thermal conductivity of the aerogel thermal insulation layer at 25°C is not higher than 0.019W / (m·k), and the thermal conductivity of the aerogel sound insulation layer at 25°C is not higher than 0.022W / (m·k); the sound insulation of the aerogel thermal insulation layer and the aerogel sound insulation layer are both not lower than 20db.

[0013] Furthermore, the aerogel matrix includes one or more of silica aerogel, alumina aerogel, carbon aerogel, iron oxide aerogel or zirconium oxide aerogel.

[0014] Furthermore, more than 90% of the volume of the aerogel matrix is ​​gas, with a three-dimensional nanoparticle skeleton (typical size of skeleton particles is 2-5nm), a high specific surface area (500-1200m 2 / g), and nanoscale pores (typical pore size is about 15-25nm).

[0015] Furthermore, the fiber reinforcement is a two-dimensional fiber fabric, which is obtained by mixing one or more of quartz fiber, basalt fiber, glass fiber, carbon fiber, high silica fiber, alumina fiber, zirconia fiber, mullite fiber, aramid fiber, polyacrylonitrile fiber or polypropylene fiber.

[0016] Furthermore, the thickness of the inner layer is 0.4-0.6 mm, and the thickness of the outer protective layer is 0.3-0.5 mm.

[0017] Furthermore, the thickness of the aerogel thermal insulation layer is 5-10 mm, and the thickness of the aerogel sound insulation layer is 10-30 mm.

[0018] Furthermore, the thermal conductivity of the aerogel insulation layer is 0.015-0.019 W / (m·k) at 25°C, 0.014-0.016 W / (m·k) at 0°C, and 0.039-0.041 W / (m·k) at 300°C.

[0019] Furthermore, the thermal conductivity of the aerogel sound insulation layer at 25° C. is 0.020-0.022 W / (m·k).

[0020] Furthermore, the density of the aerogel insulation layer is 170-220 kg / m 3 , tensile strength ≥200kPa.

[0021] Furthermore, the density of the aerogel sound insulation layer is 90-183 kg / m 3 , tensile strength ≥390kPa.

[0022] Furthermore, the moisture permeability of the aerogel thermal insulation layer and the aerogel sound insulation layer is no more than 6.4×10 -11 g / (m 2 ·s·Pa).

[0023] Furthermore, the ends of the rectangular heat-insulating and sound-insulating air duct units are provided with external plug-in sealed flanges, and adjacent rectangular heat-insulating and sound-insulating air duct units are fixed by clamping the external plug-in sealed flanges with the flat insert strips.

[0024] The present invention also provides an application of an inorganic aerogel thermal insulation and sound insulation composite air duct, wherein the inorganic aerogel thermal insulation and sound insulation composite air duct is applied to ventilation equipment of a ship system.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) The inorganic aerogel heat-insulating and sound-insulating composite air duct of the present invention can reduce and lower the resonance and noise caused by the operation of the air duct while achieving the functions of heat insulation and cold preservation, and has good application prospects in the field of ventilation ducts of ship systems.

[0027] (2) The inorganic aerogel thermal insulation and sound insulation composite air duct of the present invention can effectively isolate the thermal kinetic energy of solid molecules, the convective kinetic energy of gas molecules and the thermal radiation energy by setting aerogel insulation layers and aerogel sound insulation layers with different component ratios, significantly reducing thermal shock and energy loss, and can also provide a highly tortuous flow flow for air molecules through multi-scale heterogeneous structures and layered pores, thereby effectively isolating the propagation of noise, so that it exhibits high sound absorption and attenuation effects in a wide frequency range of noise, and takes into account the thermal insulation performance, sound insulation performance and economy of the composite air duct to the greatest extent.

[0028] (3) The aerogel thermal insulation layer and the aerogel sound insulation layer of the present invention are both provided with fiber reinforcements. The dense fiber structure of the fiber reinforcements can effectively block sound and achieve a good sound insulation effect.

[0029] (4) The inorganic aerogel thermal insulation and sound insulation composite air duct of the present invention is not limited to use in normal temperature environments, but can also be used in medium temperature zones, high temperature zones and extreme environments to continuously provide a quiet and comfortable environment, and ensure that facilities and equipment can operate safely in a stable environment, thereby increasing their service life.

[0030] (5) The inorganic aerogel thermal insulation and sound insulation composite air duct of the present invention adopts lightweight alloy inner and outer layers and lightweight aerogel thermal insulation layer and sound insulation layer, making the entire composite air duct lighter, convenient for loading and unloading, energy-saving and electricity-saving, and weight-reducing and efficiency-increasing. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the structure of the heat-insulating and sound-insulating composite air duct wall of the present invention.

[0032] Figure 2 It is a schematic structural diagram of the external plug-in sealed flange and the flat insert strip of the present invention.

[0033] Description of the markings in the figure:

[0034] 1-inner layer, 2-aerogel thermal insulation layer, 3-aerogel sound insulation layer, 4-outer protective layer, 5-external plug-in sealing flange, 6-flat insert. DETAILED DESCRIPTION

[0035] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0036] Unless otherwise specified, the reagents, methods, instruments and equipment used in the present invention are conventional reagents, methods, instruments and equipment in the art. Unless otherwise specified, the reagents and materials used in the following examples are commercially available.

[0037] In the following embodiments and comparative examples, both the inner layer and the outer protective layer are made of aluminum zinc coated sheet.

[0038] In the following examples and comparative examples, the aerogel insulation layer and the aerogel sound insulation layer are prepared by conventional methods. The present invention provides one of the preparation methods, which is as follows: weigh 25% silica gel solution, 1 mol / L hydrochloric acid and 4 mol / L ammonium fluoride, and mix the three in a weight ratio of 100:3:3 as an aerogel precursor solution; pour the aerogel precursor solution into a pre-laid fiber felt dipped mold, exhaust and stand at room temperature for 48 hours. Then, the fiber felt soaked with aerogel liquid is placed in an aging kettle for polycondensation reaction to control the total mass ratio of the aerogel matrix in the aerogel layer. After taking out and drying, it is immersed in anhydrous ethanol again for 48 hours, and then placed in a drying kettle for CO2 supercritical drying. The dried aerogel insulation layer is subjected to high temperature treatment in a muffle furnace at 600°C for 1 hour, and then placed in a vacuum tank for surface hydrophobic treatment using trimethylmethoxysilane, and finally aerogel insulation layers and aerogel sound insulation layers with different aerogel matrix mass ratios are obtained.

[0039] In the following embodiments and comparative examples, the performance indicators of the obtained thermal insulation and sound insulation composite air ducts are measured by the following methods: thermal conductivity, measured in accordance with GB / T10295 standard; flame retardancy, measured in accordance with the non-combustibility requirements of Part 1 of the FTP rules of the International Fire Test Procedure Application Rules; sound insulation performance, measured in accordance with GB / T 19889.3-2005; water repellency, measured in accordance with GB / T 10299-1988; moisture permeability, measured in accordance with GB / T 17146-2015 Test method for water vapor permeability of building materials and their products; mass moisture absorption rate and density, measured in accordance with GB / T The mass moisture absorption rate test conditions are 50℃, 95%RH, 96h; the anti-condensation performance is in accordance with the condensation test of Tongji University's "JG / G258-2009 Non-metallic and Composite Ducts"; the impact resistance of ducts is measured in accordance with Q / 725-1419-2019; the air leakage performance is measured in accordance with Tongji University's "GB 50243-2016 Ventilation and Air Conditioning Engineering Construction Quality Acceptance Code"; the toxicity test is measured in accordance with GJB 3881-1999.

[0040] Embodiment 1:

[0041] This embodiment provides an inorganic aerogel heat-insulating and sound-insulating composite air duct, which is composed of a plurality of continuous rectangular heat-insulating and sound-insulating air duct units assembled in sequence. Figure 1-2 As shown, the end of the rectangular heat-insulating and sound-insulating air duct unit is provided with an external plug-in sealed flange, and the adjacent rectangular heat-insulating and sound-insulating air duct units are fixed by the external plug-in sealed flange and the flat insert strip. The pipe wall of the rectangular heat-insulating and sound-insulating air duct unit is a layered structure, which is composed of an inner layer, an aerogel insulation layer, an aerogel sound insulation layer and an outer protective layer from the inside to the outside. The thickness of the inner layer is 0.5mm, the thickness of the outer protective layer is 0.4mm, the thickness of the aerogel insulation layer is 10mm, and the thickness of the aerogel sound insulation layer is 10mm.

[0042] The aerogel thermal insulation layer and the aerogel sound insulation layer of this embodiment are both composed of an aerogel matrix and a fiber reinforcement, wherein the aerogel matrix is ​​a silica aerogel and the fiber reinforcement is a quartz fiber felt. In the aerogel thermal insulation layer, the aerogel matrix accounts for 30wt% of the total mass, and the average fiber diameter of the fiber reinforcement is in the range of 1-5.5μm; in the aerogel sound insulation layer, the aerogel matrix accounts for 20wt% of the total mass, and the average fiber diameter of the fiber reinforcement is in the range of 1-8.5μm.

[0043] The thermal conductivity of the aerogel insulation layer prepared in this embodiment is 0.015W / (m·k) at 0°C, 0.017W / (m·k) at 25°C, 0.040W / (m·k) at 300°C, tensile strength ≥200kPa, hydrophobicity 99.5%, and mass moisture absorption rate less than 1%. The density of the aerogel sound insulation layer is 145kg / m 3 The thermal conductivity at 25°C is 0.021W / (m·k), the tensile strength is ≥390kPa, the hydrophobicity is 99.6%, and the mass moisture absorption rate is less than 1%.

[0044] Embodiment 2:

[0045] This embodiment provides an inorganic aerogel thermal insulation and sound insulation composite air duct, which is different from Embodiment 1 in that, in the aerogel thermal insulation layer of this embodiment, the aerogel matrix accounts for 20wt% of the total mass, and the average fiber diameter of the fiber reinforcement is in the range of 1-5.5μm; in the aerogel sound insulation layer, the aerogel matrix accounts for 25wt% of the total mass.

[0046] Embodiment 3:

[0047] This embodiment provides an inorganic aerogel thermal insulation and sound insulation composite air duct, which is different from Embodiment 1 in that, in the aerogel thermal insulation layer of this embodiment, the aerogel matrix accounts for 40wt% of the total mass, and the average fiber diameter of the fiber reinforcement is in the range of 1-5.5μm; in the aerogel sound insulation layer, the aerogel matrix accounts for 10wt% of the total mass.

[0048] Embodiment 4:

[0049] This embodiment provides an inorganic aerogel thermal insulation and sound insulation composite air duct, which is different from Embodiment 1 in that the thickness of the aerogel sound insulation layer in this embodiment is 30 mm.

[0050] The relevant performance test results of the thermal insulation and sound insulation composite air duct finally obtained in the above embodiments 1-3 are shown in the following table:

[0051]

[0052]

[0053] As can be seen from the above table, the inorganic aerogel thermal insulation and sound insulation composite air ducts finally assembled in Examples 1-3 of the present invention all have low thermal conductivity, low moisture absorption and moisture permeability, and pass the tests of non-flammability, toxicity detection, impact performance, vibration performance, etc. In addition, the inorganic aerogel thermal insulation and sound insulation composite air ducts of Examples 1-3 all have good sound insulation performance.

[0054] Comparative Example 1:

[0055] This comparative example provides an inorganic aerogel composite air duct, which is different from Example 1 in that this comparative example only includes an inner layer and an outer protective layer, and has no aerogel insulation layer and aerogel sound insulation layer.

[0056] Comparative Example 2:

[0057] This comparative example provides an inorganic aerogel composite air duct, which is different from Example 1 in that this comparative example only includes an inner layer, an outer protective layer and an aerogel insulation layer, but no aerogel sound insulation layer.

[0058] Comparative Example 3:

[0059] This comparative example provides an inorganic aerogel composite air duct, which is different from Example 1 in that this comparative example only includes an inner layer, an outer protective layer and an aerogel sound insulation layer, but no aerogel heat insulation layer.

[0060] Comparative Example 4:

[0061] This comparative example provides an inorganic aerogel composite air duct, which is different from Example 1 in that the thickness of the aerogel sound insulation layer in this comparative example is 50 mm.

[0062] Comparative Example 5:

[0063] In this comparative example, commercially available Armaflex insulation material (Armaflex DS) is used as the insulation layer between the inner layer and the outer protective layer. The thickness of the Armaflex insulation layer is 10-20 mm.

[0064] The relevant performance test results of the thermal insulation and sound insulation composite air ducts finally prepared in the above comparative examples 1-5 are shown in the following table:

[0065]

[0066]

[0067] It can be seen from the above table that in the absence of both the aerogel insulation layer and the sound insulation layer, the air duct of comparative example 1 has a higher thermal conductivity at room temperature and almost no cold insulation effect. In comparative examples 2 and 3, when there is only a separate aerogel insulation layer or sound insulation layer, the thermal conductivity is increased and the sound insulation is reduced, indicating that if the two are used alone, the synergistic growth effect of the combination of the two on the sound insulation performance cannot be exerted. When the thickness of the aerogel sound insulation layer of comparative example 4 increases to 50mm, the sound insulation effect does not increase, but instead increases the preparation cost of the aerogel sound insulation layer. Therefore, only within the appropriate thickness range can the technical advantages of heat insulation, sound insulation and low cost be taken into account. The thermal insulation performance of the commercially available Fores thermal insulation material used in comparative example 5 is far inferior to that of the aerogel material of the present invention, and condensation is easily generated on the surface of the Fores air duct. Therefore, in comparison, the aerogel insulation material of the present invention is more suitable for application in the field of ships.

[0068] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. An inorganic aerogel thermal insulation and sound insulation composite air duct, characterized in that: The composite air duct is composed of a plurality of continuous rectangular heat-insulating and sound-insulating air duct units assembled in sequence; the pipe wall of the rectangular heat-insulating and sound-insulating air duct unit is a layered structure, which includes an inner layer, an aerogel heat-insulating layer, an aerogel sound-insulating layer and an outer protective layer from the inside to the outside; The inner layer and the outer protective layer are independently selected from one of galvanized sheet or galvanized sheet; The aerogel heat insulation layer and the aerogel sound insulation layer are both composed of an aerogel matrix and a fiber reinforcement; In the aerogel thermal insulation layer, the aerogel matrix accounts for 20-40wt% of the total mass, and the average fiber diameter of the fiber reinforcement is 1-5.5μm; in the aerogel sound insulation layer, the aerogel matrix accounts for 10-25wt% of the total mass, and the average fiber diameter of the fiber reinforcement is 1-8.5μm; The thermal conductivity of the aerogel thermal insulation layer at 25°C is not higher than 0.019W / (m·k), and the thermal conductivity of the aerogel sound insulation layer at 25°C is not higher than 0.022W / (m·k); the sound insulation of the aerogel thermal insulation layer and the aerogel sound insulation layer are both not lower than 20db.

2. The inorganic aerogel thermal insulation and sound insulation composite air duct according to claim 1, characterized in that: The aerogel matrix includes one or more of silica aerogel, alumina aerogel, carbon aerogel, iron oxide aerogel or zirconium oxide aerogel.

3. The inorganic aerogel thermal insulation and sound insulation composite air duct according to claim 1, characterized in that: The fiber reinforcement is a two-dimensional fiber fabric, which is obtained by mixing and weaving one or more of quartz fiber, basalt fiber, glass fiber, carbon fiber, high silica fiber, alumina fiber, zirconia fiber, mullite fiber, aramid fiber, polyacrylonitrile fiber or polypropylene fiber.

4. The inorganic aerogel thermal insulation and sound insulation composite air duct according to claim 1, characterized in that: The thickness of the inner layer is 0.4-0.6 mm, and the thickness of the outer protective layer is 0.3-0.5 mm.

5. The inorganic aerogel thermal insulation and sound insulation composite air duct according to claim 1, characterized in that: The thickness of the aerogel heat insulation layer is 5-10 mm, and the thickness of the aerogel sound insulation layer is 10-30 mm.

6. The inorganic aerogel thermal insulation and sound insulation composite air duct according to claim 1, characterized in that: The thermal conductivity of the aerogel insulation layer is 0.015-0.019 W / (m·k) at 25°C, 0.014-0.016 W / (m·k) at 0°C, and 0.039-0.041 W / (m·k) at 300°C; The thermal conductivity of the aerogel sound insulation layer at 25° C. is 0.020-0.022 W / (m·k).

7. The inorganic aerogel thermal insulation and sound insulation composite air duct according to claim 1, characterized in that: The density of the aerogel insulation layer is 170-220 kg / m 3 , tensile strength ≥ 200kPa; The density of the aerogel sound insulation layer is 90-183 kg / m 3 , tensile strength ≥390kPa.

8. The inorganic aerogel thermal insulation and sound insulation composite air duct according to claim 1, characterized in that: The moisture permeability of the aerogel heat insulation layer and the aerogel sound insulation layer is not greater than 6.4×10 -11 g / (m 2 ·s·Pa).

9. The inorganic aerogel thermal insulation and sound insulation composite air duct according to claim 1, characterized in that: The ends of the rectangular heat-insulating and sound-insulating air duct units are provided with external plug-in sealed flanges, and adjacent rectangular heat-insulating and sound-insulating air duct units are fixed by clamping the external plug-in sealed flanges with the flat insert strips.

10. An application of the inorganic aerogel thermal insulation and sound insulation composite air duct according to any one of claims 1 to 9, characterized in that: The inorganic aerogel heat-insulating and sound-insulating composite air duct is applied to ventilation equipment of a ship system.

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