A double-tank self-pressurizer series on-line self-generating normal-temperature nitrogen blowing replacement system

Abstract

The present application relates to a kind of double-tank self-pressurizer series online self-generation normal temperature nitrogen blowing replacement system, belong to low temperature equipment technical field.The system of the present application, including: liquid nitrogen tank car, low temperature medium storage tank, first gasifier, second gasifier, valve F1-F13.At present, when nitrogen replacement is stored in tank, fixed gas source is mostly used, but for small system, fixed gas source is high in cost, poor in flexibility.The present application uses nitrogen tank car to prepare nitrogen source for replacement, saves the construction cost of fixed gas source, and the liquid nitrogen tank car has the characteristics of small footprint, movable, and can blow and replace any storage tank anytime and anywhere.

Description

Technical Field

[0001] This invention belongs to the field of cryogenic equipment technology, specifically relating to a purging and replacement system for online self-generated ambient temperature nitrogen using a dual-tank self-pressurizing unit connected in series. Background Technology

[0002] With the development and maturation of cryogenic technology in my country, cryogenic media such as liquid hydrogen, liquid oxygen, and liquid nitrogen are increasingly being used in various aspects of production and daily life. However, due to their low temperatures and high evaporation rates, cryogenic containers require high sealing performance during the design process. Therefore, purging of containers before storing cryogenic media is particularly important. Currently, most cryogenic containers are purged and purged with high-pressure nitrogen at the manufacturing plant before leaving the factory. However, after the containers leave the factory, due to storage environment limitations, it may be difficult to find readily available high-pressure nitrogen for purging, leading to difficulties in purging cryogenic containers.

[0003] Currently, when purging cryogenic storage tanks, a high-pressure gas source is typically used to purge the interior of the container multiple times. However, high-pressure gas source equipment is bulky and costly to build, and many of the supporting equipment are difficult to move once built. Cryogenic storage containers, on the other hand, can be moved according to usage requirements. When there is no high-pressure gas source nearby, timely purging may be impossible. Summary of the Invention

[0004] (a) Technical problems to be solved

[0005] The technical problem to be solved by this invention is how to provide a dual-tank self-pressurizing online self-generated ambient temperature nitrogen purging and replacement system, so as to solve the problems of large high-pressure gas source equipment, high construction cost, and difficulty in moving many supporting equipment once they are built.

[0006] (II) Technical Solution

[0007] To address the aforementioned technical problems, this invention proposes a dual-tank self-pressurizing online self-generated ambient temperature nitrogen purging and replacement system. This system includes: a liquid nitrogen tanker, a cryogenic medium storage tank, a first vaporizer, a second vaporizer, and valves F1-F13; wherein:

[0008] The liquid nitrogen tanker has a total of 5 ports. The pressurization ports Z1 and Z2 are located on the upper and lower parts of the vehicle body, respectively, and are connected by a vacuum tube. From port Z2 to port Z1, a shut-off valve F1, a regulating valve F2, and a first vaporizer are installed sequentially on the vacuum tube. A discharge port P1 is located on the top of the vehicle body, and the discharge port P1 is used for depressurization inside the vehicle through a discharge valve F12. A liquid phase outlet Y1 is located on the side of the vehicle body for discharging liquid nitrogen. The liquid phase outlet Y1 is connected to a connecting pipe through a liquid phase pipe, and valves F3 and F4 are installed on the liquid phase pipe. A gas phase outlet Q1 is also located on the top of the vehicle body for discharging nitrogen from the gas pillow. The gas phase outlet Q1 is connected to the liquid phase pipe between valves F3 and F4 through a single-layer pipe and valve F5.

[0009] The connecting pipe is a detachable vacuum hose, used to connect and disconnect the liquid nitrogen tanker and the cryogenic medium storage tank;

[0010] The cryogenic medium storage tank has a total of 5 ports. The pressurization ports Z3 and Z4 are located at the top and bottom of the tank body, respectively, and are connected by a vacuum tube. From port Z4 to port Z3, a shut-off valve F6, a regulating valve F7, and a second vaporizer are installed sequentially on the vacuum tube. A discharge port P2 is provided at the top of the tank body, and the discharge port P2 is used for depressurization inside the tank through a discharge valve F13. A liquid phase outlet Y2 is provided on the side of the tank body for discharging liquid nitrogen. The liquid phase outlet Y2 is connected to the filling system through a liquid outlet pipe for liquid nitrogen filling. Valves F8 and F9 are provided on the liquid phase pipe. A gas phase outlet Q2 is also provided at the top of the tank body for discharging nitrogen in the gas pillow. The gas phase outlet Q2 is connected to the liquid outlet pipe between valves F8 and F9 through a single-layer pipe and valve F10.

[0011] (III) Beneficial Effects

[0012] This invention proposes an online self-generating ambient temperature nitrogen purging and replacement system using a dual-tank self-pressurizing unit. Nitrogen purging in storage tanks typically requires an external high-pressure gas source, currently mostly using fixed gas sources. However, for small systems, fixed gas sources are costly and lack flexibility. This invention uses a liquid nitrogen tanker to generate the purging nitrogen source, saving the construction costs of fixed gas sources. Furthermore, liquid nitrogen tankers are compact, mobile, and can be used to purge and replace any storage tank anytime, anywhere. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the online self-generated ambient temperature nitrogen purging and replacement system of the dual-tank self-pressurizing unit of the present invention. Detailed Implementation

[0014] To make the objectives, contents, and advantages of the present invention clearer, the specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples.

[0015] To facilitate the purging / replacement of cryogenic medium storage tanks at any time, a dual-tank self-pressurizing system with online self-generated ambient temperature nitrogen was designed. The cryogenic medium storage tank is connected to a liquid nitrogen tanker. Ambient temperature nitrogen is extracted by the self-pressurizing liquid nitrogen tanker, and then the nitrogen pressure is further increased by the self-pressurizing equipment of the cryogenic medium storage tank, so as to purge / replace the cryogenic medium storage tank at any time without a high-pressure gas source.

[0016] Figure 1 The present invention provides a dual-tank self-pressurizing online self-generated ambient temperature nitrogen purging and replacement system, comprising: a liquid nitrogen tanker, a cryogenic medium storage tank, a first vaporizer, a second vaporizer, and valves F1-F13; wherein:

[0017] The liquid nitrogen tanker has a total of 5 ports. The pressurization ports Z1 and Z2 are located on the upper and lower parts of the vehicle body, respectively, and are connected by a vacuum tube. From port Z2 to port Z1, a shut-off valve F1, a regulating valve F2, and a first vaporizer are installed sequentially on the vacuum tube. A discharge port P1 is located on the top of the vehicle body, and the discharge port P1 is used for depressurization inside the vehicle through a discharge valve F12. A liquid phase outlet Y1 is located on the side of the vehicle body for discharging liquid nitrogen. The liquid phase outlet Y1 is connected to a connecting pipe through a liquid phase pipe, and valves F3 and F4 are installed on the liquid phase pipe. A gas phase outlet Q1 is also located on the top of the vehicle body for discharging nitrogen from the gas pillow. The gas phase outlet Q1 is connected to the liquid phase pipe between valves F3 and F4 through a single-layer pipe and valve F5.

[0018] The connecting pipe is a detachable vacuum hose, used to connect and disconnect the liquid nitrogen tanker and the cryogenic medium storage tank;

[0019] The cryogenic medium storage tank has a total of 5 ports. The pressurization ports Z3 and Z4 are located at the top and bottom of the tank body, respectively, and are connected by a vacuum tube. From port Z4 to port Z3, a shut-off valve F6, a regulating valve F7, and a second vaporizer are installed sequentially on the vacuum tube. A discharge port P2 is provided at the top of the tank body, and the discharge port P2 is used for depressurization inside the tank through a discharge valve F13. A liquid phase outlet Y2 is provided on the side of the tank body for discharging liquid nitrogen. The liquid phase outlet Y2 is connected to the filling system through a liquid outlet pipe for liquid nitrogen filling. Valves F8 and F9 are provided on the liquid phase pipe. A gas phase outlet Q2 is also provided at the top of the tank body for discharging nitrogen in the gas pillow. The gas phase outlet Q2 is connected to the liquid outlet pipe between valves F8 and F9 through a single-layer pipe and valve F10.

[0020] Furthermore, Figure 1 The first and second vaporizers are heat exchange devices. The nitrogen medium flowing out from the liquid nitrogen tanker or tank exchanges heat with the external environment through the vaporizer, thereby increasing the temperature and pressure of the nitrogen. F1 to F13 are valves, of which F2 and F7 are regulating valves used to regulate the flow rate of the nitrogen medium, and the remaining valves are shut-off valves used to block the flow of the nitrogen medium.

[0021] Furthermore, the connecting pipe is a disassembly tool. When purging and replacement are required, the pipeline connecting the liquid nitrogen tanker and the cryogenic medium storage tank is removed after the replacement is completed, which facilitates the movement of the liquid nitrogen tanker and the replenishment of liquid nitrogen.

[0022] Furthermore, F12 and F13 are discharge valves, which can be used to relieve pressure when the pressure inside the tank is too high.

[0023] Furthermore, under normal circumstances, when the connecting pipe is disconnected, the cryogenic medium storage tank is self-pressurized via F6 and F7. The pressurization forces the medium inside the tank into the outlet pipe, which then flows out through F8 and F9. The outlet pipe is designed to run from the top of the tank to the bottom. The pipe located at F10 is a gas phase pipe. When the system connected to the cryogenic medium storage tank requires nitrogen, nitrogen evaporated from the upper part of the tank can be taken from this pipe and output through F9. The purpose is to form a gas seal through the temperature difference between the top and bottom of the tank, thereby reducing heat exchange inside the pipe when the tank is storing liquid.

[0024] Furthermore, when it is necessary to purge and replace the cryogenic medium storage tank, the liquid nitrogen in the liquid nitrogen tanker is first heated and vaporized through the first vaporizer via F1 and F2. The vaporized nitrogen is stored in the upper part of the liquid nitrogen tanker and connected to the vaporization pipeline of the cryogenic medium storage tank through the connecting pipe via valves F5 and F4. It undergoes secondary vaporization and pressurization before entering the cryogenic medium storage tank. The purge and replacement nitrogen is discharged through F8 and F9.

[0025] Furthermore, when replenishing the cryogenic medium in the cryogenic medium storage tank, it is necessary to pre-cool the tank first to prevent damage caused by sudden cooling. When pre-cooling is required, cold nitrogen gas can be produced from a liquid nitrogen tanker. By controlling the flow rate of the liquid nitrogen tanker via regulating valve F2, the temperature of the cold nitrogen produced by the tanker can be controlled. After the cold nitrogen gas is taken from the top of the tanker, it is directly introduced into the cryogenic medium storage tank through valves F5, F4, and F6 to pre-cool the tank. After pre-cooling, the liquid nitrogen in the tanker can be transferred to the cryogenic medium tank via valve F3.

[0026] The beneficial effects of this invention are:

[0027] Nitrogen purging of storage tanks typically requires an external high-pressure gas source, currently mostly using fixed gas sources. However, for small systems, fixed gas sources are costly and lack flexibility. This invention uses a nitrogen tanker truck to generate the purging nitrogen source, saving the construction cost of a fixed gas source. Furthermore, liquid nitrogen tankers are small in size and mobile, allowing for purging and purging of any storage tank anytime, anywhere.

[0028] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A two-tank self-pressurizer series on-line autogenously normal-temperature nitrogen gas blowing displacement system, characterized in that, The system includes: a liquid nitrogen tanker, a cryogenic medium storage tank, a first vaporizer, a second vaporizer, and valves F1-F13; wherein: The liquid nitrogen tanker has a total of 5 ports. The pressurization ports Z1 and Z2 are located on the upper and lower parts of the vehicle body, respectively, and are connected by a vacuum tube. From port Z2 to port Z1, a shut-off valve F1, a regulating valve F2, and a first vaporizer are installed sequentially on the vacuum tube. A discharge port P1 is located on the top of the vehicle body, and the discharge port P1 is used for depressurization inside the vehicle through a discharge valve F12. A liquid phase outlet Y1 is located on the side of the vehicle body for discharging liquid nitrogen. The liquid phase outlet Y1 is connected to a connecting pipe through a liquid phase pipe, and valves F3 and F4 are installed on the liquid phase pipe. A gas phase outlet Q1 is also located on the top of the vehicle body for discharging nitrogen from the gas pillow. The gas phase outlet Q1 is connected to the liquid phase pipe between valves F3 and F4 through a single-layer pipe and valve F5. The connecting pipe is a detachable vacuum hose, used to connect and disconnect the liquid nitrogen tanker and the cryogenic medium storage tank; The cryogenic medium storage tank has a total of 5 ports. Pressure boosting ports Z3 and Z4 are located at the top and bottom of the tank, respectively, and are connected by a vacuum tube. From port Z4 to port Z3, a shut-off valve F6, a regulating valve F7, and a second vaporizer are sequentially installed on the vacuum tube. A discharge port P2 is located at the top of the tank, and is used for depressurization within the tank via a discharge valve F13. A liquid phase outlet Y2 is located on the side of the tank for discharging liquid nitrogen. Liquid phase outlet Y2 is connected to the filling system via a liquid outlet pipe for liquid nitrogen filling. Valves F8 and F9 are installed on the liquid phase pipe. A gas phase outlet Q2 is also located at the top of the tank for discharging nitrogen from the gas pillow. Gas phase outlet Q2 is connected to the liquid outlet pipe via a single-layer pipe and valve F10 between valves F8 and F9. in, The liquid outlet pipe is designed to run from the top of the tank to the bottom. The pipe where F10 is located is a gas phase pipe. When the system connected to the cryogenic medium storage tank needs nitrogen, the nitrogen evaporated from the upper part of the tank is taken from this pipe and output through F9. The temperature difference between the top and bottom of the tank forms a gas seal, which reduces heat exchange inside the pipe when the tank is storing liquid.

2. The dual-tank self-pressurizing unit connected in series with an online self-generated ambient temperature nitrogen purging and replacement system as described in claim 1, characterized in that, The first and second vaporizers are heat exchange devices. The nitrogen medium flowing out of the liquid nitrogen tanker or tank exchanges heat with the external environment through the vaporizer, thereby increasing the temperature and pressure of the nitrogen.

3. The dual-tank self-pressurizing unit connected in series with an online self-generated ambient temperature nitrogen purging and replacement system as described in claim 1, characterized in that, F2 and F7 are regulating valves used to regulate the flow rate of nitrogen medium, while the remaining valves are shut-off valves used to block the flow of nitrogen medium.

4. The dual-tank self-pressurizing unit connected in series with an online self-generated ambient temperature nitrogen purging and replacement system as described in claim 1, characterized in that, The connecting pipe is a disassembly tool. It connects the liquid nitrogen tanker and the cryogenic medium storage tank when purging and replacement are required. It is removed after the replacement is completed and is used for moving the liquid nitrogen tanker and replenishing liquid nitrogen.

5. The online self-generated ambient temperature nitrogen purging and replacement system with a dual-tank self-pressurizing unit as described in claim 1, characterized in that, F12 and F13 are discharge valves, used to relieve pressure when the pressure inside the tank is too high.

6. The dual-tank self-pressurizing unit connected in series with an online self-generated ambient temperature nitrogen purging and replacement system as described in any one of claims 1-5, characterized in that, Under normal circumstances, when the connecting pipe is disconnected, the cryogenic medium storage tank is pressurized by F6 and F7, and the medium in the tank is forced into the outlet pipe through F8 and F9.

7. The dual-tank self-pressurizing unit connected in series with an online self-generated ambient temperature nitrogen purging and replacement system as described in claim 6, characterized in that, When the cryogenic medium storage tank needs to be purged and replaced, the liquid nitrogen in the liquid nitrogen tanker is first heated and vaporized through the first vaporizer via F1 and F2. The vaporized nitrogen is stored in the upper part of the liquid nitrogen tanker and is connected to the vaporization pipeline of the cryogenic medium storage tank through the connecting pipe via valves F5 and F4. It undergoes secondary vaporization and pressurization before entering the cryogenic medium storage tank. The nitrogen after purging and replacement is discharged through F8 and F9.

8. The dual-tank self-pressurizing unit connected in series with an online self-generated ambient temperature nitrogen purging and replacement system as described in claim 6, characterized in that, When replenishing the cryogenic medium in the cryogenic medium storage tank, the cryogenic medium storage tank is first pre-cooled. When pre-cooling the cryogenic medium storage tank is required, cold nitrogen gas for pre-cooling is produced by a liquid nitrogen tanker. The temperature of the cold gas produced by the liquid nitrogen tanker is controlled by controlling the flow rate of the regulating valve F2. After taking cold nitrogen gas from the top of the liquid nitrogen tanker, it is directly introduced into the cryogenic medium storage tank through valves F5, F4, and F6 to pre-cool the tank.

9. The online self-generated ambient temperature nitrogen purging and replacement system with a dual-tank self-pressurizer in series as described in claim 8, characterized in that, After precooling, the liquid nitrogen in the liquid nitrogen tanker is transferred to the cryogenic medium tank through valve F3.

Images