Double-valve linkage vacuum filling device for liquid hydrogen storage tank and using method of double-valve linkage vacuum filling device

Abstract

The invention provides a double-valve linkage vacuum packing device for a liquid hydrogen storage tank and a using method thereof, and the device comprises a packing container which is arranged at the top of the liquid hydrogen storage tank, the upper part of the packing container is connected with a packing pump, and the bottom of the packing container is communicated with a vacuum layer of the liquid hydrogen storage tank; the double-valve mechanism comprises a filler valve arranged between the upper part of the filler container and the filler pump, and a connecting valve arranged between the lower part of the filler container and the liquid hydrogen storage tank; the vacuumizing mechanism comprises a vacuumizing assembly connected with the filler container through an exhaust pipeline and a pressure sensor arranged on the filler container; and the controller is respectively connected with the filler pump, the filler valve, the connecting valve, the vacuumizing assembly and the pressure sensor, and is used for firstly filling the filler container with filler, then vacuumizing the filler container to a certain degree and finally enabling the filler to fall into a vacuum layer of the liquid hydrogen storage tank. The technical problems that in the prior art, due to the fact that filling is conducted firstly and then vacuumizing is conducted, the construction period is long, the efficiency is low, filling is not uniform easily, and the vacuum degree does not reach the standard are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of filling of liquid hydrogen storage tanks, and in particular to a double-valve linkage vacuum filling device for liquid hydrogen storage tanks and a use method thereof. Background Art

[0002] Liquid hydrogen storage tanks are widely used in aerospace, energy storage, hydrogen fuel supply and other fields. Their low-temperature storage characteristics require liquid hydrogen storage tanks to have efficient insulation capabilities. At present, large liquid hydrogen storage tanks mainly use medium vacuum or low vacuum + filling insulation materials (such as hollow glass microspheres, perlite, etc.) to reduce heat conduction. However, during the filling process of existing large liquid hydrogen storage tanks, insulation materials (such as glass microspheres) are usually filled once, and then vacuumed. The presence of a large number of glass microspheres hinders the discharge of gas, resulting in a long construction period and low efficiency. It is also easy to have problems such as uneven filling and substandard vacuum.

[0003] In view of the above problems, the present invention provides an optimized design combining a filling device with an exhaust device, which can improve the vacuuming efficiency, speed up the construction speed and ensure the uniform filling of the insulation material. Summary of the invention

[0004] The purpose of the present invention is to provide a double-valve linkage vacuum filling device for liquid hydrogen storage tanks and a method of using the same, which solves the above-mentioned technical problems of long construction period, low efficiency, uneven filling and substandard vacuum.

[0005] This embodiment provides a double-valve linkage vacuum filling device for a liquid hydrogen storage tank, comprising: A packing container is arranged on the top of the liquid hydrogen storage tank, and a packing pump is connected to its upper part, and its bottom is used to communicate with the vacuum layer of the liquid hydrogen storage tank; A double valve mechanism, comprising a packing valve disposed between the upper portion of the packing container and the packing pump, and a connecting valve disposed between the lower portion of the packing container and the liquid hydrogen storage tank; A vacuum pumping mechanism, comprising a vacuum pumping assembly connected to the filling container via a vacuum pipe, and a pressure sensor disposed on the filling container; The controller is respectively connected to the filling pump, the filling valve, the connecting valve, the vacuum pumping assembly and the pressure sensor, and is used to first load the filling container with filling materials, then draw a certain vacuum on the filling container, and finally make the filling materials fall into the vacuum layer of the liquid hydrogen storage tank.

[0006] Furthermore, the controller has the following built-in modules: Control module; A vacuum pump switching module is connected to the control module and is used to automatically control the start and stop of the vacuum pumping component according to the vacuum degree data fed back by the pressure sensor; The valve linkage module is connected to the control module and is used to control the opening and closing of the filling valve and the connecting valve and the working state of the filling pump according to the process of first filling, then vacuuming and finally blanking.

[0007] Furthermore, the vacuum pumping assembly includes a low vacuum pump first used for rough pumping and then a high vacuum pump used for fine pumping.

[0008] Furthermore, the low vacuum pump adopts a pump group consisting of a Roots pump and a rotary vane pump connected in series, and the high vacuum pump adopts a molecular pump.

[0009] Furthermore, it also includes a heating mechanism, which includes a heating belt wrapped around the outer wall of the filling container, a temperature sensor embedded in the inner wall of the container, and a PID temperature control module connected to the heating belt and the temperature sensor; The controller also has a built-in temperature control module connected to the control module, which is used to dynamically adjust the power of the heating belt according to the PID temperature control module data to maintain a constant temperature state.

[0010] Furthermore, the filling container is a funnel-shaped container with a cone angle of 40° to 50°, and the inner wall thereof is treated with nano-coating or mirror polishing.

[0011] Furthermore, a filter blanket is provided at the inlet of the filling container which is connected to the air extraction pipeline. The pore size of the filter blanket is smaller than that of the filling material and the filter blanket is detachable and replaceable.

[0012] Furthermore, a bellows compensator is provided at the connection between the exhaust pipeline and the filling container to absorb thermal expansion and contraction deformation.

[0013] This embodiment also provides a method for using a double-valve linkage vacuum packing device for a liquid hydrogen storage tank. The method is used for the double-valve linkage vacuum packing device for a liquid hydrogen storage tank, and the method includes the following steps: S1. First, evacuate the vacuum layer of the liquid hydrogen storage tank by an external vacuum pump or the vacuum pumping mechanism to reach a target vacuum degree; S2, close the connecting valve and open the filling valve, the filling pump works, and injects a certain amount of filling into the filling container through the feeding pipe; S3, close the packing valve, start the vacuum pumping mechanism to evacuate the packing container; first use the low vacuum pump to roughly evacuate the packing container, and when the pressure drops to a certain level, switch to the high vacuum pump to perform fine evacuation until the pressure reaches the target vacuum degree; S4. After reaching the target vacuum degree, the controller controls the opening of the connecting valve to allow the filler in the filler container to fall into the vacuum layer of the liquid hydrogen storage tank under the action of gravity; the S2-S4 operations are cycled, and the "filling → vacuuming → dropping" process is repeated until the vacuum layer is filled with a certain amount of filler.

[0014] This embodiment also provides another method for using a double-valve linkage vacuum packing device for a liquid hydrogen storage tank. The method is used for the above-mentioned double-valve linkage vacuum packing device for a liquid hydrogen storage tank, and the method includes the following steps: S1. First, evacuate the vacuum layer of the liquid hydrogen storage tank by an external vacuum pump or the vacuum pumping mechanism to reach a target vacuum degree; S2, start the heating mechanism to heat the filling container through the heating belt, and the heating temperature is controlled by the PID temperature control module; S3, close the connecting valve and open the filling valve, the filling pump starts to work, and injects a certain amount of filling into the filling container through the filling delivery pipeline; S4, close the packing valve, start the vacuum pumping mechanism to evacuate the packing container; first use the low vacuum pump to roughly evacuate the packing container, and when the pressure drops to a certain level, switch to the high vacuum pump to perform fine evacuation until the pressure reaches the target vacuum degree; S5. The controller controls the opening of the connecting valve to allow the filler in the filler container to fall into the vacuum layer of the liquid hydrogen storage tank under the action of gravity; the S3-S5 operations are cycled, and the "filling → vacuuming → dropping" process is repeated until the vacuum layer is filled with a certain amount of filler.

[0015] Compared with the prior art, the beneficial effects achieved by the present invention include at least: The vacuum filling device combines the filling container with the vacuum pumping mechanism to achieve synchronous operation of vacuum pumping and filling. Since the glass microspheres fall freely in a vacuum environment rather than being affected by airflow or external interference, they are not prone to form segregation or uneven accumulation during the filling process, which helps to improve the uniformity of the vacuum layer, filling efficiency and vacuum degree. The controller realizes fully automated operation of vacuum pump switching, valve linkage and temperature control, reducing manual intervention, operational errors and risks. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1A schematic diagram of the structure of a double-valve linkage vacuum packing device for a liquid hydrogen storage tank provided in this embodiment; Figure 2 A flow chart of a method for using the double-valve linkage vacuum filling device for a liquid hydrogen storage tank provided in this embodiment.

[0018] icon: 10-filling container; 20-liquid hydrogen storage tank; 30-filling pump; 40-double valve mechanism; 41-filling valve; 42-connecting valve; 50-vacuum pumping mechanism; 51-vacuum pumping assembly; 52-pressure sensor; 60-controller; 70-heating mechanism; 71-heating belt; 72-temperature sensor; 73-PID temperature control module; 80-Glass microspheres. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0022] The present invention provides a double valve linkage vacuum packing device for liquid hydrogen storage tanks, please refer to Figure 1 As shown, it includes a filling container 10, a filling pump 30, a double valve mechanism 40, a vacuum mechanism 50, a controller 60 and a heating mechanism 70.

[0023] Among them, the filling container 10 adopts a funnel-shaped container, which is connected to the top of the liquid hydrogen storage tank 20, and is connected to the vacuum layer of the liquid hydrogen storage tank 20 through a connecting pipe, serving as a vacuum space; the volume of the funnel-shaped container can be 5% of the volume of the vacuum layer of the liquid hydrogen storage tank 20, the cone angle can be 40°~50°, the inner wall is nano-coated or mirror-polished, and the material is 304 stainless steel; the interface between the feeding pipeline and the funnel-shaped container adopts a flange sealing structure and is fixed to the top of the storage tank by bolts; in addition, the funnel-shaped container is smaller in size and simpler in structure than the annular vacuum layer, and can directly contact the external environment. The open structure of the funnel can also reduce powder residue, and the cleaning process is convenient and quick, reducing maintenance time and improving production efficiency.

[0024] The double valve mechanism 40 includes a packing valve 41 disposed at the top of the funnel-shaped container and a connecting valve 42 at the bottom, which are used to control the connection state between the packing container 10 and the vacuum layer of the liquid hydrogen storage tank 20; in the double valve mechanism 40: the packing valve 41 can be a pneumatic butterfly valve, located at the feed port at the top of the funnel-shaped container; the connecting valve 42 can be an electric stop valve, located between the bottom of the funnel-shaped container and the storage tank, and specifically, the feed valve on the storage tank can be used as the connecting valve 42; the packing valve 41 and the connecting valve 42 are both connected to the controller 60 (mostly a PLC controller) through a signal line, and are opened and closed according to a preset program; The vacuum mechanism 50 includes a vacuum assembly 51 connected to the filling container 10, and a pressure sensor 52 arranged on the filling container 10; the vacuum assembly 51 is connected to the funnel-shaped container through an exhaust pipe to evacuate the funnel-shaped container; the vacuum assembly 51 includes a low vacuum pump group and a high vacuum pump, and the low vacuum pump group is composed of a Roots pump and a rotary vane pump in series, which is used to initially evacuate the funnel-shaped container to 100 Pa; the high vacuum pump is a molecular pump, which can further evacuate the vacuum in the funnel-shaped container to 6.67Pa; the low vacuum pump group and the high vacuum pump work together to significantly shorten the construction time and improve the construction efficiency; the optimized design of the vacuum pump group reduces energy consumption, and the device uses a molecular pump as a high vacuum pump. Compared with a diffusion pump, the molecular pump has many advantages such as energy saving, environmental protection, and cost saving; in addition, the inlet of the exhaust pipe is covered with a filter blanket to prevent the glass microspheres 80 from entering the pipe while allowing gas to pass through; the filter blanket can be fixed to the inner wall of the pipe by a clamp for easy disassembly and cleaning; in addition, the pressure sensor 52 is embedded in the funnel-shaped container for real-time monitoring of the vacuum in the funnel and feedback to the controller 60; in addition, a bellows compensator is provided at the connection between the exhaust pipe and the funnel-shaped container to absorb thermal expansion and contraction deformation.

[0025] The controller 60 is connected to the dual valve mechanism 40, the heating mechanism 70, the vacuum mechanism 50, the temperature sensor 72, the filling pump 30 and the pressure sensor 52 through a signal line to realize the full process automatic operation. The controller 60 has the following built-in functional modules: a control module; a vacuum pump switching module, connected to the control module, for automatically controlling the start and stop of the low vacuum pump group and the high vacuum pump according to the vacuum degree data fed back by the pressure sensor 52; a valve linkage module, connected to the control module, for controlling the opening and closing of the filling valve 41 and the connecting valve 42 and the working state of the filling pump 30 according to the "filling → vacuum → blanking" process; a temperature control module, connected to the control module, dynamically adjusting the power of the heating belt 71 according to the data of the PID temperature control module 73 to maintain a constant temperature state.

[0026] The heating mechanism 70 includes a heating belt 71 wound around the outer wall of the funnel-shaped container, a temperature sensor 72 embedded in the inner wall of the container, a PID temperature control module 73 connecting the heating belt 71 and the temperature sensor 72, and a heat-insulating material outside the heating belt; the heating belt 71 can be evenly wound around the outer wall of the funnel-shaped container in a spiral manner, and the heating temperature can be 40-80°C, and the specific heating temperature is adjusted according to the vacuum pumping rate; the outer covering of the heat-insulating material can reduce heat loss and make the heating more uniform; the temperature sensor 72 is embedded in the inner wall of the funnel-shaped container, and is connected to the PID temperature control module 73 through a signal line, and the temperature data is fed back to the controller 60 in real time; This embodiment also provides a method for using a double-valve linkage vacuum packing device for a liquid hydrogen storage tank. The method is used for the vacuum packing device, the vacuum packing device includes a heating mechanism 70, and the vacuum assembly 51 includes a low vacuum pump group and a high vacuum pump; please refer to Figure 2 As shown, the method comprises the following steps: Step 1: Before the device is officially put into operation, the annular vacuum layer of the storage tank is first evacuated by an external vacuum pump or the vacuum pumping mechanism 50. When an external vacuum pump is used, it can be directly connected to the vacuum port of the storage tank for evacuation. Similarly, in addition to evacuating the storage tank through the filling container, the vacuum pumping mechanism 50 can also be connected to the vacuum port of the storage tank through another vacuum pipe for evacuation. When pre-evacuating the storage tank, since there are no glass microspheres 80 to hinder the airflow at this time, the evacuation time is short and the target vacuum degree can be quickly reached. In this way, in the subsequent filling process, only a short-term vacuum is required for the funnel-shaped container, thereby improving the overall efficiency.

[0027] Step 2: Before filling, pre-treat the funnel-shaped container, start the heating mechanism 70, and the heating belt 71 evenly heats the outer wall of the funnel-shaped container in a spiral winding manner. The temperature is controlled by the PID temperature control module 73. The heating temperature range can be 40~80℃, and the specific heating temperature is determined by the vacuuming rate. During the heating process, the temperature sensor 72 monitors the temperature of the inner wall of the container in real time to ensure that the adsorbed moisture and volatile substances are fully desorbed, thereby reducing the resistance in the subsequent vacuuming stage.

[0028] Step 3: Filling operation: close the connecting valve 42 and open the filling valve 41, and the filling pump 30 works to inject the hollow glass microspheres 80 into the funnel-shaped container through the glass microsphere 80 delivery pipeline.

[0029] Step 4: After the funnel-shaped container is filled to a certain extent, such as when it is full, the filling valve 41 is closed, and the vacuum mechanism 50 is started to evacuate the funnel-shaped container. This process is divided into two stages, including a low vacuum stage, in which the funnel-shaped container is roughly evacuated by a low vacuum pump group, and the pressure sensor 52 monitors the pressure change in real time; when the pressure drops to 100 Pa or ≤100Pa, the controller 60 triggers a switching command to enter a high vacuum stage; in this stage, the low vacuum pump group is closed, and the molecular pump is started for fine pumping, and the air is continuously pumped until the pressure reaches 6.67 Pa (corresponding to 5×10⁻² Torr). This vacuum degree can effectively eliminate the influence of residual gas in the gaps between microspheres on the thermal insulation performance.

[0030] Step 5: The controller 60 controls the connection valve 42 to open. Under the action of gravity, the hollow glass microspheres 80 slide evenly into the vacuum layer of the storage tank along the cone surface of the funnel, and the loop logic repeats the process of "filling → vacuuming → blanking" until the vacuum layer is filled to a certain extent, such as completely filled. In addition, the filling amount of the filling container 10 can be controlled by the pumping amount per unit time and the pumping time; the filling amount of the vacuum layer of the storage tank can be controlled based on the pre-filled amount of the filling container 10, the ratio of the filling volume to the filling volume of the vacuum layer, and the number of filling times.

[0031] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A double-valve linkage vacuum filling device for a liquid hydrogen storage tank, characterized in that: include: A filling container (10) is arranged on the top of the liquid hydrogen storage tank (20), and the upper part thereof is connected to a filling pump (30), and the bottom part thereof is used to communicate with the vacuum layer of the liquid hydrogen storage tank (20); A double valve mechanism (40) comprising a filling valve (41) arranged between an upper portion of the filling container (10) and the filling pump (30), and a connecting valve (42) arranged between a lower portion of the filling container (10) and the liquid hydrogen storage tank (20); A vacuum pumping mechanism (50) comprising a vacuum pumping component (51) connected to the filling container (10) via a vacuum pipeline, and a pressure sensor (52) arranged on the filling container (10); The controller (60) is respectively connected to the filling pump (30), the filling valve (41), the connecting valve (42), the vacuum pumping assembly (51) and the pressure sensor (52), and is used to first load the filling container (10), then evacuate a certain amount of vacuum on the filling container (10), and finally allow the filling to fall into the vacuum layer of the liquid hydrogen storage tank (20).

2. The double-valve linkage vacuum filling device for liquid hydrogen storage tank according to claim 1, characterized in that: The controller (60) has the following built-in modules: Control module; A vacuum pump switching module connected to the control module, and used to automatically control the start and stop of the vacuum pumping component (51) according to vacuum degree data fed back by the pressure sensor (52); The valve linkage module is connected to the control module and is used to control the opening and closing of the filling valve (41) and the connecting valve (42) and the working state of the filling pump (30) according to the process of first filling, then vacuuming and finally blanking.

3. The double-valve linkage vacuum filling device for a liquid hydrogen storage tank according to claim 2, characterized in that: The vacuum pumping assembly (51) comprises a low vacuum pump first used for rough pumping and a high vacuum pump later used for fine pumping.

4. The double-valve linkage vacuum filling device for a liquid hydrogen storage tank according to claim 3, characterized in that: The low vacuum pump adopts a pump group consisting of a Roots pump and a rotary vane pump connected in series, and the high vacuum pump adopts a molecular pump.

5. The double-valve linkage vacuum filling device for a liquid hydrogen storage tank according to claim 3, characterized in that: It also includes a heating mechanism (70), the heating mechanism (70) including a heating belt (71) wound around the outer wall of the filling container (10), a temperature sensor (72) embedded in the inner wall of the container, and a PID temperature control module (73) connected to the heating belt (71) and the temperature sensor (72); The controller (60) also has a built-in temperature control module connected to the control module, which is used to dynamically adjust the power of the heating belt (71) according to data from the PID temperature control module (73) to maintain a constant temperature state.

6. The double-valve linkage vacuum filling device for a liquid hydrogen storage tank according to claim 1, characterized in that: The filling container (10) is a funnel-shaped container, the cone angle of which is 40° to 50°, and the inner wall of which is subjected to nano-coating or mirror polishing.

7. The double-valve linkage vacuum filling device for a liquid hydrogen storage tank according to claim 1, characterized in that: A filter blanket is provided at the inlet of the filling container (10) which is connected to the air extraction pipeline. The filter blanket has a pore size smaller than that of the filling material and is detachable and replaceable.

8. The double-valve linkage vacuum filling device for a liquid hydrogen storage tank according to claim 1, characterized in that: A bellows compensator is provided at the connection between the exhaust pipeline and the filling container (10) for absorbing thermal expansion and contraction deformation.

9. A method for using a double-valve linkage vacuum filling device for a liquid hydrogen storage tank, characterized in that: The method of use is used for the double-valve linkage vacuum filling device for a liquid hydrogen storage tank according to claim 3, and the method of use comprises the following steps: S1, first evacuating the vacuum layer of the liquid hydrogen storage tank (20) by means of an external vacuum pump or the vacuum evacuation mechanism (50) to achieve a target vacuum degree; S2, closing the connecting valve (42) and opening the filling valve (41), and the filling pump (30) starts to work, injecting a certain amount of filling into the filling container (10) through the feeding pipe; S3, closing the packing valve (41), and starting the vacuum pumping mechanism (50) to evacuate the packing container (10); firstly, roughly evacuate the packing container (10) using a low vacuum pump, and when the pressure drops to a certain level, switch to a high vacuum pump to perform fine evacuation until the pressure reaches a target vacuum degree; S4. The controller (60) controls the opening of the connecting valve (42) so that the filler in the filler container (10) falls into the vacuum layer of the liquid hydrogen storage tank (20) under the action of gravity; the operations of S2 to S4 are circulated, and the "filler→vacuuming→dropping" process is repeated until a certain amount of filler is filled in the vacuum layer.

10. A method for using a double-valve linkage vacuum filling device for a liquid hydrogen storage tank, characterized in that: The method of use is used for the double-valve linkage vacuum filling device for a liquid hydrogen storage tank according to claim 5, and the method of use comprises the following steps; S1, first evacuating the vacuum layer of the liquid hydrogen storage tank (20) by means of an external vacuum pump or the vacuum evacuation mechanism (50) to achieve a target vacuum degree; S2, starting the heating mechanism (70) to heat the filling container (10) via the heating belt (71), wherein the heating temperature is controlled by the PID temperature control module (73); S3, closing the connecting valve (42) and opening the filling valve (41), and the filling pump (30) starts to operate, injecting a certain amount of filling into the filling container (10) through the filling delivery pipeline; S4, closing the packing valve (41), and starting the vacuum pumping mechanism (50) to evacuate the packing container (10); firstly, roughly evacuate the packing container (10) using a low vacuum pump, and when the pressure drops to a certain level, switch to a high vacuum pump to perform fine evacuation until the pressure reaches a target vacuum degree; S5. The controller (60) controls the opening of the connecting valve (42) so that the filler in the filler container (10) falls into the vacuum layer of the liquid hydrogen storage tank (20) under the action of gravity; the operations of S3 to S5 are circulated, and the "filler→vacuuming→dropping" process is repeated until a certain amount of filler is filled in the vacuum layer.

Images