JPH04324082A - Cryogenic gas recovery device - Google Patents

Abstract

PURPOSE:To obtain an inexpensive cryogenic gas recovery device, high in safety upon recovering cryogenic gas. CONSTITUTION:Both ends of a gas circulating pipeline 14 are connected to a gas recovery. pack 3 while an ejector 16 for choking the flow passage of gas and a blower 15 for circulating gas are arranged in the route of the gas circulating pipeline 14. One end of a gas recovery pipeline 7, whose other ends are connected to a cryogenic facility 1, reserving liquid helium 2, a recovered gas liquid Dewar flask 5 and a moving gas liquid Dewar flask 6 respectively, is connected to one end of the ejector 16. Gas in the gas recovery pack 3 flows through the gas circulating pipeline 14 by the power of the blower 15, then, the flow passage of the gas is choked by the ejector 16 to increase the flow speed of the gas and induce helium gas in the gas recovery pipeline 7, then, returns into the gas recovery pack 3. The helium gas, recovered into the gas recovery pack 3, is liquefied into liquid helium 2 by a gas liquefying and recovering device 4 to recover it.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cryogenic gas recovery apparatus for liquefying and recovering cryogenic gas generated in a cryogenic medium tank storing a cryogenic medium.

0002

2. Description of the Related Art FIG. 3 is a system diagram showing the connection state of a conventional cryogenic gas recovery device. In the figure, 1 is cryogenic equipment that uses liquid helium 2, which is a cryogenic medium, 3 is a cryogenic gas recovery bag, and 4 is connected to this cryogenic gas recovery bag 3, and the cryogenic gas recovery bag 3 collects the gas. A gas liquefaction recovery device that liquefies helium gas; 5 is a recovered gas-liquid dua for storing liquid helium 2 liquefied and recovered by the gas liquefaction recovery device 4; 6 is a moving gas-liquid dua for moving the liquid helium 2; Reference numeral 7 indicates a gas recovery pipe that communicates the cryogenic medium tanks of the cryogenic equipment 1, the recovered gas-liquid dua 5, and the moving gas-liquid dua 6 with the cryogenic gas recovery bag 3, and 8 is provided in the cryogenic gas recovery bag 3. relief valve, 9, 10
are respectively a gas liquefaction recovery device 4 and a recovered gas liquid dur 5, and a recovered gas liquid dur 5 and a gas liquid dur for transportation 6.
Pipes 11, 12, and 13 that communicate with each other are valves.

Next, the operation of the conventional cryogenic gas recovery apparatus shown in FIG. 3 will be explained. First, it is assumed that liquid helium 2 is stored in the cryogenic equipment 1, the recovered gas-liquid dua 5, and the moving gas-liquid dua 6. Cryogenic equipment 1,
The recovered gas-liquid dua 5 and the moving gas-liquid dua 6 are filled with helium gas generated from the liquid helium 2. Therefore, if the valves 11, 12, and 13 are opened,
Cryogenic equipment 1, gas recovery bag 3, gas liquefaction recovery device 4
, a recovered gas liquid dur 5, a moving gas liquid dur 6, a gas recovery pipe 7, etc. constitute a closed circuit, and the helium gas in the cryogenic equipment 1, the recovered gas liquid dur 5, and the moving gas liquid dur 6 is used for gas recovery. The gas is introduced into the gas recovery bag 3 through the pipe 7, and is liquefied and recovered into liquid helium by the gas liquefaction recovery device 4. At this time, the internal pressure of the gas recovery bag 3 and the gas recovery pipe 7 is maintained at a pressure slightly higher than atmospheric pressure, for example, 0.1 kg/cm2 or less, by the relief valve 8.

0004

[Problems to be Solved by the Invention] As described above, in the conventional cryogenic gas recovery apparatus, the collected gas liquid dewar 5, the moving gas liquid dua 6, etc. constitute a closed circuit during the cryogenic gas recovery operation. , cryogenic equipment 1, recovered gas liquid dua 5,
There was a problem in that the internal pressure of the cryogenic medium tank such as the moving gas-liquid dua 6 was higher than atmospheric pressure, and a general atmosphere-opening type container could not be used as a container for the gas recovery system.

[0005] This invention was made in order to solve the above-mentioned problems, and allows a cryogenic medium tank incorporated in a closed system during cryogenic gas recovery to be easily brought to atmospheric pressure or a negative pressure close to atmospheric pressure. The objective is to obtain a highly safe and inexpensive cryogenic gas recovery device that can maintain high pressure.

[0006]

[Means for Solving the Problems] A cryogenic gas recovery apparatus according to the present invention is provided with suction means for sucking cryogenic gas in a cryogenic medium tank on the path of a gas recovery pipe.

[0007]

[Operation] In this invention, the suction means sucks the cryogenic gas generated in the cryogenic medium tank through the gas recovery pipe, so that the inside of the cryogenic medium tank becomes a negative pressure.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings. FIG. 1 is a system diagram showing one embodiment of the connection state of the cryogenic gas recovery device of the present invention, and FIG. 2 is a sectional view of the ejector in FIG. 1, which is the same as the conventional cryogenic gas recovery device shown in FIG. 3. Or equivalent parts are given the same reference numerals and their explanations are omitted. 14 is connected at both ends to the gas recovery bag 3,
Gas circulation piping for circulating the gas in the gas recovery bag 3, 1
A blower 5 is disposed in the path of the gas circulation piping 14 and is used to circulate the gas in the gas recovery bag 3 through the gas circulation piping 14; 16 is disposed in the path of the gas circulation piping 14; The ejector is connected at one end to the gas recovery pipe 7 and narrows down the flow path of the circulating gas and sucks the recovered gas.In this embodiment, the gas circulation pipe 14
, a blower 15 for gas circulation, and an ejector 16 constitute a suction means.

Next, the operation of the above embodiment will be explained. First, like the conventional cryogenic gas recovery apparatus shown in FIG. 3, the valves 11, 12, and 13 are opened to make the gas recovery path a closed circuit. Here, the blower 15 is driven to circulate the gas in the gas recovery bag 3 through the gas circulation pipe 14. The gas flow circulating in the gas circulation pipe 14 has its flow path narrowed in the ejector 16 to increase the flow velocity, sucks helium gas in the gas recovery pipe 7, and passes through the gas recovery bag 3.
Go back inside. At this time, cryogenic equipment 1, recovered gas liquid dua 5
The pressure inside the moving gas-liquid dua 6 is reduced as the helium gas in the gas recovery pipe 7 is sucked.

[0010] Here, if the set pressure of the relief valve 8 is set close to atmospheric pressure, the pressure in each tank of the cryogenic equipment 1, the recovered gas liquid dewar 5, and the moving gas liquid dua 6 will be below atmospheric pressure. In addition, even if the amount of recovered gas changes, the internal pressure of the gas recovery piping 7 hardly changes, so even if there are multiple cryogenic equipment 1, the pressure inside the tank will not change. This increases safety, and allows the use of ordinary, inexpensive containers that are open to the atmosphere as containers for these gas recovery systems.

Note that in the above embodiment, the gas circulation pipe 14
Although the explanation uses the blower 15 as the power for circulating the gas inside, the same effect can be achieved even if a fan, pump, compressor, etc. are used.

Furthermore, in the above embodiment, the gas circulation pipe 14
Although the ejector 16 is provided in the path to narrow the gas flow path, increase the gas flow rate, and suck the helium gas in the gas recovery pipe 7, the present invention is not limited to the ejector 16.

Further, in the above embodiment, the suction means is composed of the gas circulation pipe 14, the blower 15, and the ejector 16, but the same effect can be achieved even if the blower 15 is used alone.

Furthermore, in the above embodiment, the cryogenic equipment 1,
Although the recovery gas liquid dewar 5 and the moving gas liquid dua 6 are each described as being one unit, the same effect can be obtained even if one of them is not used or a plurality of each is used.

Furthermore, in the above embodiments, liquid helium is used as the cryogenic medium, but the present invention is not limited thereto.

[0016]

As described above, according to the present invention, since the cryogenic gas suction means is provided in the path of the gas recovery piping that communicates the cryogenic medium tank and the gas recovery bag, the cryogenic gas recovery A cryogenic medium tank sometimes incorporated in a closed system can be easily maintained at atmospheric pressure or a negative pressure close to atmospheric pressure, which has the effect of providing a highly safe and inexpensive cryogenic gas recovery device.

[Brief explanation of drawings]

FIG. 1 is a system diagram showing an embodiment of the connection state of a cryogenic gas recovery apparatus of the present invention.

FIG. 2 is a sectional view showing an ejector in the cryogenic gas recovery device of FIG. 1.

FIG. 3 is a system diagram showing an example of a connection state of a conventional cryogenic gas recovery device.

[Explanation of symbols]

1 Cryogenic equipment (cryogenic medium tank) 2 Liquid helium 3 Gas recovery bag 4 Gas liquefaction recovery device 5 Recovery gas liquid dua (cryogenic medium tank) 6
Moving gas liquid dua (cryogenic medium tank) 7 Gas recovery piping 14 Gas circulation piping (suction means) 15 Blower (suction means) 16 Ejector (suction means)

Claims (1)

[Claims] 1. A cryogenic gas recovery bag, a gas liquefaction recovery device connected to the cryogenic gas recovery bag, and a cryogenic medium tank storing a cryogenic medium are communicated with the cryogenic gas recovery bag. In the cryogenic gas recovery apparatus that liquefies and recovers the cryogenic gas generated in the cryogenic medium tank, the gas recovery piping includes a suction means for sucking the cryogenic gas in the cryogenic medium tank. A cryogenic gas recovery device characterized in that it is installed on a path of.