Filling device and filling method for cryogenic spherical tank interlayer cold insulation material

Abstract

A filling device for cryogenic spherical tank interlayer cold insulation materials is characterized in that an air outlet of a nitrogen tank is in sealed communication with an inlet of a pneumatic dust pump sequentially through a valve and a nitrogen pipeline, and a cold insulation material filling box is in sealed communication with the inlet of the pneumatic dust pump through a cold insulation material conveying pipe I; the top interlayer of the cryogenic spherical tank is hermetically communicated with the pneumatic dust pump through a cold insulation material conveying pipe II; a vacuumizing opening is formed in an interlayer at the bottom of the cryogenic spherical tank and is hermetically communicated with a vacuumizing pipeline, a high-vacuum baffle valve is mounted on the vacuumizing pipeline at the vacuumizing opening, and the tail end of the vacuumizing pipeline is hermetically communicated with a filter; the cooling water system is connected with a water inlet and a water outlet of the vacuum pump unit; and the vibration motor is mounted at the lower part of the outer spherical tank of the cryogenic spherical tank. According to the filling method, a positive pressure compaction technology, gas transmission and closed conveying are adopted. The device is simple in structure and convenient to install, the filling efficiency and the heat insulation performance can be greatly improved, and the heat loss of the cryogenic spherical tank is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of cryogenic spherical tank cold insulation material filling, and specifically relates to a filling device and a filling method for the cold insulation material in the interlayer of a cryogenic spherical tank. Background Art

[0002] Cryogenic technology can improve product quality, extend service life, and reduce production costs. Along with the more than 100-year development process of cryogenic technology and its continuous progress, the gas industry has achieved rapid development. The applications of cryogenic liquids such as liquid oxygen, liquid nitrogen, liquid argon, liquid helium, liquid hydrogen, and liquefied natural gas have expanded from industries such as machinery, petroleum, and chemical engineering to fields such as energy, environmental protection, shipbuilding, transportation, biology, and aerospace, and the demand is increasing rapidly year by year. At the same time, with the continuous growth of the world's energy demand and the increasing awareness of environmental protection, the promotion and application of clean energy such as liquid hydrogen and liquefied natural gas have become the development focus in the energy field of today's society. With the wide application of cryogenic liquids, it has driven the rapid development of cryogenic vacuum insulation containers (hereinafter referred to as "cryogenic containers"). Currently, cryogenic containers have developed into the fastest-growing and most promising industry in the pressure vessel industry.

[0003] Cryogenic containers mainly include spherical storage tanks (spherical storage tanks are also called spherical tanks) and cylindrical storage tanks. Compared with cylindrical storage tanks, for spherical storage tanks, under the same volume and the same pressure, the surface area of the spherical tank is the smallest. Therefore, the spherical tank requires less steel area and has a smaller heat transfer area, and the heat leakage rate is low under the same conditions; the spherical tank is uniformly stressed, and its load-bearing capacity is twice that of the cylindrical storage tank, and the material cost is lower. Nowadays, under the background of the development of equipment towards large-scale, the application of cryogenic spherical tanks is more extensive.

[0004] A cryogenic spherical tank consists of an inner tank and an outer tank. The interlayer space between the inner and outer parts needs to be filled with cold insulation materials. After being filled densely and then evacuated to a qualified vacuum degree, it plays the role of vacuum insulation in the interlayer. The cold insulation materials are generally granular loose materials, which have characteristics such as small volume, low thermal conductivity, and good chemical stability. Due to the characteristics of the cold insulation materials, their filling density and moisture content have a greater impact on the insulation performance, making it difficult for the vacuum powder insulation layer to have insulation performance at low temperatures, thus failing to meet the usage requirements of the equipment. Since the spherical tank is a large-scale storage device, the interlayer space is dozens or even hundreds of times larger than that of the cylindrical storage tank interlayer space, which brings greater challenges to filling and evacuation. If the filling time is too long, the water and impurities adsorbed by the pearlite sand will affect the evacuation efficiency and the cold insulation effect. During the filling process, if the pearlite sand is not compacted, during use, due to the thermal expansion and contraction of the inner cylinder, the cold insulation materials will continuously sink and be compacted, resulting in a part of the vacuum interlayer of the spherical tank not being filled with cold insulation materials, which will inevitably reduce the insulation performance of the container.

[0005] At present, there are problems in the filling of cold insulation materials for cryogenic containers, such as low efficiency, large leakage during the filling process, and poor filling effect. Moreover, it is mostly applied to cylindrical storage tanks, and the filling of cold insulation materials for spherical cryogenic containers is almost blank. For example, in Chinese Patent CN 116357880 A (a perlite filling device and process), the compaction of the cold insulation material adopts an impact and intermittent form and is applied to a cylindrical shape. Therefore, in view of the above problems, a filling device and method for the cold insulation material in the interlayer of a cryogenic spherical tank are proposed. Summary of the Invention

[0006] The present invention provides a filling device and a filling method for the cold insulation material in the interlayer of a cryogenic spherical tank, which have a simple structure and are convenient to install, and can greatly improve the filling efficiency and reduce the heat loss of the cryogenic spherical tank.

[0007] The technical solutions adopted by the present invention are as follows: A filling device for the cold insulation material in the interlayer of a cryogenic spherical tank includes a nitrogen tank, a cold insulation material filling box, a pneumatic dust pump, a vacuum pump unit, a vibration motor, a high-vacuum baffle valve, a filter, and a cooling water system; the air outlet of the nitrogen tank is sequentially and hermetically connected to the inlet of the pneumatic dust pump through a valve and a nitrogen pipeline, the cold insulation material filling box is hermetically connected to the inlet of the pneumatic dust pump through a cold insulation material transportation pipe I, and the top interlayer of the cryogenic spherical tank is hermetically connected to the pneumatic dust pump through a cold insulation material transportation pipe II; a vacuum extraction port is provided at the bottom interlayer of the cryogenic spherical tank, and the vacuum extraction port is hermetically connected to a vacuum extraction pipeline. A high-vacuum baffle valve is installed on the vacuum extraction pipeline at the vacuum extraction port, and the tail end of the vacuum extraction pipeline is hermetically connected to the filter; the vacuum pump unit is connected to the filter, and the cooling water system is connected to the inlet and outlet of the vacuum pump unit; the vibration motor is installed at the lower part of the outer spherical tank of the cryogenic spherical tank.

[0008] Four layers of stainless steel wire meshes are provided at the vacuum extraction port.

[0009] A vacuum gauge is installed at the inlet position of the filter.

[0010] The nitrogen pipeline, the cold insulation material transportation pipe I, and the cold material transportation pipe II all adopt flexible hoses.

[0011] A filling method for a filling device for the cold insulation material in the interlayer of a cryogenic spherical tank. First, turn on the cooling water system, then turn on the vacuum pump, and then turn on the vacuum baffle valve to pre-pump the vacuum for the interlayer of the cryogenic spherical tank. When the vacuum gauge shows that the pressure reaches 5×10 4When the pressure reaches Pa, open the valve, and use the nitrogen pressure to drive the pneumatic dust pump to work. The cold insulation material is sucked into the pneumatic dust pump from the cold insulation material filling box, and then the cold insulation material is injected into the interlayer by the nitrogen pressure and the negative pressure in the interlayer of the cryogenic spherical tank. Due to the continuous vacuum pumping of the vacuum pump unit, the cold insulation material entering the interlayer moves rapidly downward together with the nitrogen. The four-layer stainless steel wire mesh at the inlet of the vacuum pumping port blocks the cold insulation material, and the gas flows out, causing the cold insulation material to accumulate and compact from the bottom. While pumping vacuum, turn on the vibration motor to further compact the cold insulation material, effectively improving the filling effect and heat insulation ability.

[0012] The present invention adopts the positive pressure compaction technology, continuously evacuates the interlayer before and during filling to increase the bulk density of the cold insulation material, thereby enhancing the heat insulation effect and also accelerating the filling speed; adopts gas transmission and closed transportation, greatly improving the transportation efficiency, reducing dust leakage, and preventing workers from contacting harmful substances; the vibration motor is connected to the bracket preset outside the outer spherical tank through bolts to compact the cold insulation material during filling, further improving the heat insulation effect. The structure of the present invention is simple and easy to install, can greatly improve the filling efficiency, reduce the heat loss of the cryogenic spherical tank, and has a significant effect, and can be widely applied to cryogenic spherical tanks such as liquid hydrogen, LNG, liquid nitrogen, liquid oxygen, and liquid argon. Brief Description of the Drawings

[0013] Figure 1 is the structural block diagram of the filling device of the present invention; In the figure: 1. Nitrogen tank; 2. Valve; 3. Nitrogen pipeline; 4. Cold insulation material filling box; 5. Cold insulation material transportation pipe I; 6. Pneumatic dust pump; 7. Cold insulation material transportation pipe II; 8. Cryogenic spherical tank; 9. Vacuum gauge; 10. Filter; 11. Cooling water system; 12. High vacuum baffle valve; 13. Vibration motor; 14. Vacuum pumping pipeline; 15. Vacuum pump unit. Detailed Embodiments

[0014] The present invention will be further described in detail below in conjunction with the drawings and embodiments.

[0015] As Figure 1As shown in the figure, a filling device for the insulation material in the interlayer of a cryogenic spherical tank includes a nitrogen tank 1, an insulation material filling box 4, a pneumatic dust pump 6, a vacuum pump unit 15, a vibration motor 13, a high-vacuum baffle valve 12, a filter 10, and a cooling water system 11. The outlet of the nitrogen tank 1 is hermetically connected to the inlet of the pneumatic dust pump 6 through a valve 2 and a nitrogen pipeline 3 in sequence. The insulation material filling box 4 is hermetically connected to the inlet of the pneumatic dust pump 6 through an insulation material transportation pipe I 5. The top interlayer of the cryogenic spherical tank 8 is hermetically connected to the pneumatic dust pump 6 through an insulation material transportation pipe II 7. A vacuum extraction port is provided at the bottom interlayer of the cryogenic spherical tank 8, and this vacuum extraction port is hermetically connected to a vacuum extraction pipeline 14. A high-vacuum baffle valve 12 is installed on the vacuum extraction pipeline 14 at the vacuum extraction port. The tail end of the vacuum extraction pipeline 14 is connected to the filter 10, and secondary filtration is adopted to minimize the entry of dust into the vacuum pump, thereby preventing damage to the vacuum pump caused by dust. The vacuum pump unit 15 is hermetically connected to the filter 10, and the cooling water system 11 is hermetically connected to the inlet and outlet of the vacuum pump unit 15. The vibration motor 13 is connected to a bracket preset on the outer wall of the outer spherical tank through bolts to compact the insulation material during the filling process. The bracket and the outer spherical tank are connected through a backing plate, and multiple brackets can be set according to the size of the spherical tank and are evenly distributed.

[0016] Four layers of stainless steel wire meshes are provided at the vacuum extraction port to prevent the insulation material from being drawn out during vacuum extraction.

[0017] A vacuum gauge 9 is installed at the inlet of the filter 10 to detect the vacuum degree and pressure of the vacuum extraction pipeline.

[0018] The nitrogen pipeline 3 adopts a flexible hose for convenient installation and position movement. The insulation material transportation pipe I 5 and the cold material transportation pipe II 7 both adopt flexible hoses for convenient suction and position movement.

[0019] In the present invention, the vacuum pump unit is connected to the filter and the interlayer of the cryogenic spherical tank through pipelines. The high-vacuum baffle valve is used to control the opening and closing of the pipeline. The cooling water system is used for cooling the vacuum unit. The filter removes the drawn dust to prevent damage to the vacuum pump. The insulation material filling box is connected to the inlet of the pneumatic dust pump through a pipeline. The air inlet of the pneumatic dust pump is connected to the nitrogen tank. The insulation material filling port of the cryogenic spherical tank is connected to the outlet of the pneumatic dust pump. Nitrogen pushes the pneumatic dust pump to move, sucks the insulation material into the pump cavity, and then sends the insulation material into the interlayer of the cryogenic spherical tank through nitrogen. The whole filling process is airtight, which can greatly improve the transportation efficiency and reduce dust leakage. When filling, the vibration motor is turned on to compact the insulation material.

[0020] A filling method for a filling device for the insulation material in the interlayer of a cryogenic spherical tank. First, turn on the cooling water system 11, then turn on the vacuum pump 15, and then turn on the vacuum baffle valve 12 to pre-vacuum the interlayer of the cryogenic spherical tank 8. When the vacuum gauge 9 shows that the pressure reaches 5×10 4When the pressure is Pa, open valve 2, and use the nitrogen pressure to drive the pneumatic dust pump 6 to work. The cold insulation material is sucked into the pneumatic dust pump 6 from the cold insulation material filling box 4, and then the cold insulation material is injected into the interlayer by the nitrogen pressure and the negative pressure in the interlayer of the cryogenic spherical tank 8. Due to the continuous vacuum pumping of the vacuum pump unit 15, the cold insulation material entering the interlayer moves downward rapidly together with the nitrogen. The four-layer stainless steel wire mesh at the inlet of the vacuum pumping port blocks the cold insulation material, and the gas flows out, causing the cold insulation material to accumulate and be compacted from the bottom. While pumping vacuum, turn on the vibration motor 13 to further compact the cold insulation material, effectively improving the filling effect and heat insulation ability. During the filling process, pay attention to the pressure of the nitrogen tank 1 and the amount of cold insulation material in the cold insulation material filling box 4 at any time. When the pressure of the nitrogen tank is lower than 0.4 MPa, nitrogen should be filled into the nitrogen tank to increase the pressure to ensure the filling quality; when the height of the cold insulation material is lower than 0.2 m, the cold insulation material should be replenished in time to ensure the continuous progress of the filling process. The above description is only an application embodiment of the present invention. Of course, it cannot be used to limit the scope of the rights of the present invention. Therefore, equivalent changes made according to the scope of the patent application of the present invention still fall within the protection scope of the present invention.

Claims

1. A filling device for cryogenic insulation materials in the interlayer of a spherical tank, characterized in that, It includes a nitrogen gas tank (1), a cold insulation material filling box (4), a pneumatic dust pump (6), a vacuum pump unit (15), a vibration motor (13), a high-vacuum baffle valve (12), a filter (10), and a cooling water system (11); the outlet of the nitrogen gas tank (1) is hermetically connected to the inlet of the pneumatic dust pump (6) through a valve (2) and a nitrogen gas pipeline (3) in sequence, the cold insulation material filling box (4) is hermetically connected to the inlet of the pneumatic dust pump (6) through a cold insulation material transportation pipe I (5), the top interlayer of the cryogenic spherical tank (8) is hermetically connected to the pneumatic dust pump (6) through a cold insulation material transportation pipe II (7); a vacuum extraction port is provided at the bottom interlayer of the cryogenic spherical tank (8), this vacuum extraction port is hermetically connected to a vacuum extraction pipeline (14), a high-vacuum baffle valve (12) is installed on the vacuum extraction pipeline (14) at the vacuum extraction port, and the tail end of the vacuum extraction pipeline (14) is hermetically connected to the filter (10); the vacuum pump unit (15) is connected to the filter (10), and the cooling water system (11) is connected to the inlet and outlet of the vacuum pump unit (15); the vibration motor (13) is installed at the lower part of the outer spherical tank of the cryogenic spherical tank (8).

2. The filling device for the cryogenic insulation material in the interlayer of a cryogenic spherical tank according to claim 1, characterized in that, Four layers of stainless steel wire meshes are provided at the vacuum extraction port.

3. The filling device for the cryogenic insulation material between the spherical storage tanks according to claim 1, characterized in that, A vacuum gauge (9) is installed at the inlet position of the filter (10).

4. A filling device for cryogenic spherical tank interlayer cold insulation material according to claim 1, characterized in that, The nitrogen gas pipeline (3), the cold insulation material transportation pipe I (5), and the cold material transportation pipe II (7) all adopt flexible hoses.

5. A filling method for a filling device of an insulating material for the interlayer of a cryogenic spherical tank as described in claim 1, characterized in that, First, turn on the cooling water system (11), then start the vacuum pump (15), and then open the vacuum baffle valve (12) to pre-evacuate the interlayer of the cryogenic spherical tank (8). When the vacuum gauge (9) shows that the pressure reaches 5×10 4 Pa, open the valve (2), and use the nitrogen pressure to drive the pneumatic dust pump (6) to work. The cold insulation material is sucked into the pneumatic dust pump (6) from the cold insulation material filling box (4), and then the cold insulation material is pumped into the interlayer through the nitrogen pressure and the negative pressure of the interlayer of the cryogenic spherical tank (8). Due to the continuous evacuation of the vacuum pump unit (15), the cold insulation material entering the interlayer moves rapidly downward together with the nitrogen. The four-layer stainless steel wire mesh at the inlet of the evacuation port blocks the cold insulation material, and the gas flows out, causing the cold insulation material to accumulate and compact from the bottom. At the same time as evacuating the vacuum, turn on the vibration motor (13) to further compact the cold insulation material, effectively improving the filling effect and heat insulation ability.

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