CN112377801B

CN112377801B - A heat-insulating low-temperature container

Info

Publication number: CN112377801B
Application number: CN202011394770.0A
Authority: CN
Inventors: 白江坤; 王国营; 王沙沙; 王晓东; 王伟; 张童; 范晖
Original assignee: Shandong Auyan New Energy Technology Co ltd
Current assignee: Shandong Auyan New Energy Technology Co ltd
Priority date: 2020-12-03
Filing date: 2020-12-03
Publication date: 2024-12-17
Anticipated expiration: 2040-12-03
Also published as: CN112377801A

Abstract

The invention discloses an insulated low-temperature container, and relates to the technical field of low-temperature container insulation. A nanoporous insulation material layer and a cured resin layer are sequentially arranged on the outer wall of the inner liner of the low-temperature container. The invention wraps the nanoporous insulation material around the outer wall of the gas cylinder, and uses a cured resin to fix the strength of the outermost side of the nanoporous material, so as to meet the strength requirements of the use, transportation, and hoisting of the product.

Description

Adiabatic low temperature container

Technical Field

The invention relates to the technical field of thermal insulation of low-temperature containers, in particular to a thermal insulation low-temperature container.

Background

The prior high vacuum multi-layer heat insulation is widely adopted in the ultralow temperature container, adopts aluminum foil and glass fiber to compound into heat insulation materials, covers the outer surface of the container liner by the heat insulation materials, and then adopts a vacuum pump to pump the space between the liner and the outer liner to high vacuum so as to achieve the purpose of heat insulation.

The traditional high-vacuum multi-layer heat-insulating container has higher vacuum degree, the vacuumizing time is more than 7 days, the product is required to be heated to reach ideal vacuum requirement, the cleanliness of an interlayer (the outer surface of the inner container and the inner surface of the outer container) is very high, cleaning, drying and degreasing treatment are required, the requirements of welding seams related to the interlayer are higher, each welding part is required to be subjected to leakage detection, and the detection requirements and the detection difficulty are higher.

The vacuum of the traditional high-vacuum multi-layer heat-insulating container is difficult to maintain for a long time, although the vacuum layer is provided with adsorbing materials such as an adsorbent (molecular sieve, palladium oxide) and the like, the vacuum design life of the high-vacuum multi-layer heat-insulating container is generally 3-5 years, long-time heat insulation cannot be achieved, and the palladium oxide is high in price of noble metal market, so that the price of the vacuum heat-insulating container is high.

The patent refers to the United states space agency (NASA), the American society for testing and materials issues "flexible aerogel insulation Specification" (ASTMC 1728-17 "nanoporous aerogel composite insulation products", GB/T34336-2017 "nanoporous aerogel composite insulation products", and related documents and data of national defense science, ha Gong, zhejiang University, chinese academy of sciences, etc., further, the traditional high vacuum multilayer insulation mode is replaced by developing novel insulation materials and insulation modes.

Disclosure of Invention

In order to lighten the weight of the low-temperature container and overcome the problems, the invention adopts the following technical scheme that the heat-insulating low-temperature container comprises an inner container, wherein the inner container comprises a cylinder body, a front end enclosure and a rear end enclosure, a nano-hole heat-insulating material layer, a cured resin layer and a carbon fiber layer are sequentially arranged on the outer wall of the inner container, and support fixing mechanisms are respectively arranged on the front end enclosure and the rear end enclosure and used for fixing the nano-hole heat-insulating material layer.

Preferably, the front end socket is connected with an extension pipe, and the extension pipe is provided with a valve.

Preferably, a seventh supporting and fixing ring is arranged on the cylinder body.

Preferably, an eighth supporting and fixing ring is arranged on the cylinder body.

Preferably, the rear end socket is provided with a first supporting fixing ring, a second supporting fixing ring and a third supporting fixing ring from outside to center.

Preferably, the front end socket is provided with a fourth supporting and fixing ring, a fifth supporting and fixing ring and a sixth supporting and fixing ring from outside to center.

Preferably, the nano-porous heat insulation material layer comprises methyl orthosilicate and reinforcing fiber.

Further, the components of the reinforcing fibers include silica and alumina.

Still further, the reinforcing fiber further comprises at least one of ferric oxide, barium oxide, titanium dioxide, and calcium oxide.

Preferably, the nanoporous insulating material layer composition further comprises hexamethyldisiloxane.

Preferably, the mass part ratio of the silicon dioxide to the aluminum oxide to the ferric oxide is 53-58:40-42:0.7-1.

Preferably, the weight ratio of the methyl orthosilicate to the reinforcing fiber is 60-80:8-16.

A process for preparing the insulating nano-pore material includes such steps as mixing silicon dioxide, aluminium oxide and ferric oxide, heating to molten state, blowing molten liquid to become fibrous substance, cooling, mixing methyl orthosilicate, deionized water and hydrochloric acid, hydrolysis and polycondensation reaction to obtain sol, adding fibrous substance and ammonia water, standing for polycondensation reaction to obtain colloid, adding absolute alcohol, supercritical drying, thermal insulating, slow release of alcohol, and cooling to room temp.

The invention adopts a novel heat insulating material to replace the traditional high vacuum multi-layer heat insulating mode, innovates the novel heat insulating mode of the low-temperature container, permanently notices the problem of fatigue of high vacuum multi-layer heat insulating vacuum, thoroughly cancels the production procedures of original high vacuum multi-layer heat insulating vacuumizing, welding, outer liner leakage detection and the like, and ensures that the production process is simpler and easy to operate and the like.

By varying the type of insulation, the advantages of using nanoporous insulation materials are manifested in the following aspects:

1. Because the aerogel solid is very small in mass fraction and is a porous body, the pore diameters are in the nanometer scale, the solid phase part can be seen as being composed of a plurality of thin pore walls of micropores, the heat transfer in the solid is almost endless, and the heat transfer capacity of the solid in the aerogel is greatly weakened by the huge long path effect to be very small.

2. Because of the nano-pore structure, the material forms a solid/gas interface similar to infinity, when the rays of the heat radiation pass through each layer of interface, reflection, absorption, transmission and re-radiation can occur, which is equivalent to arranging a near infinite heat shield on the propagation path of the heat radiation, the near infinite reflection effect can quickly attenuate the propagation capability of the heat radiation, and finally most of the radiation heat conduction is absorbed on the surface layer of the heat insulation material close to the hot surface side, and the radiation heat conduction is very low at normal temperature.

3. The ultra-low convection heat transfer, the gas is subjected to convection heat transfer, enough space is needed, the pore diameter of the aerogel is generally smaller than 50nm, in the nano pores, all air molecules lose macroscopic migration capacity, and the condition of convection heat transfer is not provided, so that the convection heat transfer of the aerogel is well limited.

4. The super-strong use temperature ranges from-196 ℃ to 950 ℃.

5. The flame retardant is strong, and the material is incombustible, has unique flame penetrability and can be directly burnt after long-time flame reception.

6. The waterproof performance is good, and the hydrophobicity can reach more than 99%.

According to the invention, the nano-pore heat insulation material is wound on the outer wall of the gas cylinder, and the strength of the outer container of the low-temperature heat insulation container is fixed by adopting the solidified resin at the outermost side of the nano-pore material, so that the strength requirements of the product such as use, transportation, hoisting and the like are met.

Drawings

FIG. 1 is a schematic diagram of the structure of the present invention;

Fig. 2 is a schematic structural view of the rear end enclosure.

Detailed Description

The invention will be further described with reference to the drawings and examples.

As shown in fig. 1, an insulating low-temperature container, the liner 1 is composed of a cylinder part, and a front end enclosure 21 and a rear end enclosure 22 at two ends, wherein the front end enclosure 21 and the rear end enclosure 22 are both curved surfaces. As shown in fig. 2, the rear seal head 22 is welded with a first supporting and fixing ring 7, a second supporting and fixing ring 8 and a third supporting and fixing ring 9 in turn from outside to the center, and the front seal head 21 is welded with a fourth supporting and fixing ring 7a, a fifth supporting and fixing ring 8a and a sixth supporting and fixing ring 9a in turn from outside to the center. And a seventh supporting and fixing ring 10 is welded on the barrel part near the rear end enclosure 22, and an eighth supporting and fixing ring 10a is welded on the barrel part near the front end enclosure 21. The center of the front seal head 21 is welded with an extension tube 5, and the extension tube 5 is provided with a valve 6. The traditional front sealing head is directly provided with a bottleneck, and a valve is arranged on the bottleneck, but the curved surface of the bottleneck is complex and is not easy to completely wrap the bottleneck, so that the heat resistance is increased in a mode of reducing the heat transfer area by increasing the extension tube on the premise of meeting the strength, and the heat leakage through the extension tube is smaller.

After the manufacturing of the liner 1 is completed, the outer wall 2 of the liner is processed, then the outer wall 2 of the liner is coated with the nano-pore heat-insulating material layer 3, then the nano-pore heat-insulating material layer 3 is coated with the curing resin to form a curing resin layer 4, the outermost side of the nano-pore heat-insulating material layer is reinforced to meet the requirement of the use strength, and finally the nano-pore heat-insulating material layer 3 is wrapped and wound by carbon fibers to form a carbon fiber layer 41 to complete the processing.

It is to be noted that a standard elliptical seal head is adopted as a seal head of a gas cylinder liner, a certain curved surface exists, a high-density nano-hole heat insulation material covered by the seal head is consistent with the curved surface of the seal head by adopting compression molding, the nano-hole heat insulation material and the curved surface of the seal head are prevented from being separated in the use process in order to ensure perfect fit with the seal head of the gas cylinder liner, and the heat insulation material and the seal head of the gas cylinder are fixed.

The following examples were made for comparison in order to find the best material for the nanoporous insulating material layer.

Example one, 53 parts of silica, 42 parts of aluminum oxide, 0.8 part of iron oxide, 1 part of barium oxide, and 0.5 part of titanium dioxide were placed in an electric arc furnace and heated to 2000 ℃ or higher to a molten state, and the molten material was trickled and blown into a fiber with a high-speed gas stream. 60 parts of methyl orthosilicate, 35 parts of hexamethyldisiloxane, 15 parts of deionized water and 10 parts of hydrochloric acid are mixed and stirred to generate sol through hydrolysis and polycondensation reaction, 8 parts of the prepared fibrous substance and 18 parts of ammonia water are added, after the fibrous substance is subjected to standing polycondensation reaction to form gel, 20 parts of absolute ethyl alcohol is added after ageing, and then the fibrous substance is added into an autoclave for supercritical drying and heat preservation. Slowly releasing the ethanol, and cooling to room temperature to obtain the nano microporous thermal insulation material.

Example two, 58 parts of silica, 40 parts of aluminum oxide, 0.7 part of iron oxide, 1.2 parts of barium oxide, and 0.8 part of titanium dioxide were placed in an arc furnace and heated to a temperature of 2000 ℃ or higher to a molten state, and the molten material was trickled and blown into a fiber with a high-speed gas stream. Mixing 65 parts of methyl orthosilicate, 30 parts of hexamethyldisiloxane, 20 parts of deionized water and 15 parts of hydrochloric acid, stirring, performing hydrolysis and polycondensation reaction to generate sol, adding 8 parts of the prepared fibrous substance and 15 parts of ammonia water, standing, performing polycondensation reaction to form gel, adding 30 parts of absolute ethyl alcohol, aging, adding into an autoclave, performing supercritical drying, and preserving heat. Slowly releasing the ethanol, and cooling to room temperature to obtain the nano microporous thermal insulation material.

Example three 58 parts of silica, 40 parts of aluminum oxide, 0.7 part of iron oxide, 1.2 parts of barium oxide, and 0.8 part of titanium dioxide were placed in an electric arc furnace and heated to a temperature above 2000 ℃ to a molten state, and the molten material was trickled and blown into a fiber with a high-speed gas stream. 80 parts of methyl orthosilicate, 20 parts of deionized water and 15 parts of hydrochloric acid are mixed and stirred to generate sol through hydrolysis and polycondensation reaction, 8 parts of the prepared fibrous substance and 15 parts of ammonia water are added, after the fibrous substance is subjected to standing polycondensation reaction to form gel, 30 parts of absolute ethyl alcohol is added after the gel loses fluidity, and the gel is aged, and then the gel is added into an autoclave for supercritical drying and heat preservation. Slowly releasing the ethanol, and cooling to room temperature to obtain the nano microporous thermal insulation material.

Example four 58 parts of silica, 40 parts of aluminum oxide, 0.7 part of iron oxide, 2 parts of barium oxide were placed in an electric arc furnace and heated to above 2000 ℃ to a molten state, and a thin stream of the melt was blown into a fiber with a high velocity gas stream. 80 parts of methyl orthosilicate, 20 parts of deionized water and 15 parts of hydrochloric acid are mixed and stirred to generate sol through hydrolysis and polycondensation reaction, 16 parts of the prepared fibrous substance and 15 parts of ammonia water are added, after the fibrous substance is subjected to standing polycondensation reaction to form gel, 30 parts of absolute ethyl alcohol is added after the gel loses fluidity, and the gel is aged, and then the gel is added into an autoclave for supercritical drying and heat preservation. Slowly releasing the ethanol, and cooling to room temperature to obtain the nano microporous thermal insulation material.

Comparative example 53 parts of silica, 42 parts of aluminum oxide, 0.8 part of iron oxide, 1 part of calcium oxide were placed in an electric arc furnace and heated to above 2000C to a molten state, and the melt was trickled and blown into a fiber with a high velocity gas stream. 80 parts of methyl orthosilicate, 15 parts of deionized water and 10 parts of hydrochloric acid are mixed and stirred to generate sol through hydrolysis and polycondensation reaction, 8 parts of the prepared fibrous substance and 18 parts of ammonia water are added, after the fibrous substance is subjected to standing polycondensation reaction to form gel, 20 parts of absolute ethyl alcohol is added after the gel loses fluidity, and the gel is aged, and then the gel is added into an autoclave for supercritical drying and heat preservation. Slowly releasing the ethanol, and cooling to room temperature to obtain the nano microporous thermal insulation material.

The above examples all use parts by weight. The thermal insulation materials prepared in the above examples were subjected to thermal conductivity test and compression test, respectively, and the experimental data are as follows:

	comparative example	Example 1	Example two	Example III	Example IV
						Thermal conductivity W/(m K)	0.015	0.012	0.011	0.013	0.013
Compressive strength MPa	14.2	15.3	15.4	15.0	14.9

From the above test results, it is known that the material has the best compressive strength when the reinforcing fiber is a combination of barium oxide and titanium oxide, and the thermal conductivity of the material is the lowest when the combination of methyl orthosilicate and hexamethyldisiloxane is used. When the combination of barium oxide, titanium oxide, methyl orthosilicate, and hexamethyldisiloxane, i.e., the first and second examples, was used together, the test value as the heat insulating material for the low-temperature heat insulating container was optimal.

While the foregoing embodiments of the present invention have been described in connection with the accompanying drawings, the present invention is not limited to the scope of protection thereof, and it will be apparent to those skilled in the art that various modifications and variations can be made therein without requiring any inventive effort.

Claims

1. An insulated low-temperature container, comprising an inner liner, the inner liner comprising a cylinder, a front head, and a rear head, characterized in that a nanoporous insulation material layer, a cured resin layer, and a carbon fiber layer are sequentially arranged on the outer wall of the inner liner; the nanoporous insulation material layer is calculated by weight and is prepared as follows: 53 to 58 parts of silicon dioxide, 40 to 42 parts of aluminum oxide, 0.7 to 0.8 parts of iron oxide, 1 to 1.2 parts of barium oxide, and 0.5 to 0.8 parts of titanium dioxide are heated to Above 2000℃ until it is molten, blow the molten stream into fibrous material, mix 60-65 parts of methyl orthosilicate, 30-35 parts of hexamethyldisiloxane, 15-20 parts of deionized water, and 10-15 parts of hydrochloric acid, stir and hydrolyze and polycondense to form a sol, add 8 parts of the above-prepared fibrous material and 15-18 parts of ammonia water, let it stand for polycondensation reaction to form a gel and lose its fluidity, then add 20-30 parts of anhydrous ethanol, dry and keep warm after aging, release the ethanol and cool to room temperature.

2. The insulated low-temperature container according to claim 1 is characterized in that a supporting and fixing mechanism is provided on the outer wall of the inner liner for fixing the nanoporous insulation material layer.

3. The insulated low-temperature container according to claim 1 is characterized in that the front head and the rear head are both provided with a supporting and fixing mechanism for fixing the nanoporous insulation material layer.

4. The insulated low-temperature container according to claim 1 is characterized in that the front head is connected to an extension pipe, and the extension pipe is provided with a valve.

5 . The insulated low-temperature container according to claim 1 , wherein a seventh supporting fixing ring is provided on the cylinder.

6 . The thermally insulated low-temperature container according to claim 1 , wherein an eighth supporting and fixing ring is provided on the cylinder.

7. The insulated low-temperature container according to claim 1 is characterized in that the rear head is provided with a first supporting fixing ring, a second supporting fixing ring and a third supporting fixing ring in sequence from the outside to the center.

8. The insulated cryogenic container according to claim 1 is characterized in that the front head is provided with a fourth supporting fixing ring, a fifth supporting fixing ring and a sixth supporting fixing ring in sequence from the outside to the center.