JP7558883B2 - Liquefied gas supply device and supply method, spray freezing device and spray freezing method - Google Patents

Description

The present invention relates to a liquefied gas supply device and supply method, and a spray freezing device and spray freezing method using the device and method.

Liquefied gases such as liquid nitrogen are widely used for freezing and cooling food, as well as for freezing and storing various materials. When using liquefied gas, it is usually extracted from an insulated pressure vessel. However, because the gas itself has its own pressure, when extracted under atmospheric pressure, this pressure causes the gas to spray, and the pressure from this spray can cause the object to change shape.

Patent Document 1 shows a liquefied gas dripping device that drips liquid nitrogen in small amounts to prevent the pressure from the injection from causing changes in the shape of the object, and that keeps the liquid in a liquid state by reducing the amount of vaporization and supplies it directly to the dripping point. Patent Document 2 shows a low-temperature liquefied gas injection device equipped with an injection pipe that supplies liquid nitrogen in a mist form to efficiently cool the object.

Special Publication No. 5-43573 Patent No. 6508707

However, when using liquid nitrogen to efficiently cool an object, it is common to install a subcooler close to where the liquid nitrogen is extracted and extract it as a supercooled liquid, or to install a gas-liquid separator and extract only the liquid nitrogen. However, supplying liquid nitrogen under low pressure is difficult, and particularly when supplying a fixed amount by dripping liquid nitrogen or continuously supplying it as a mist, as in Patent Documents 1 and 2 above, the equipment required to reduce the pressure at the source or a combination of a liquid level sensor and a flow control valve must be used, which often results in complex and expensive equipment.

In view of the above, the present invention aims to provide a liquefied gas supply device and supply method that can supply liquefied gas such as liquid nitrogen at low temperature and pressure with a simple structure, as well as a spray freezing device and spray freezing method that use said device and method.

The first invention of the present invention is a liquefied gas supply device including a first liquefied gas storage section into which liquefied gas is introduced from a liquefied gas supply source through a liquefied gas introduction pipe, a second liquefied gas storage section into which liquefied gas is supplied from the first liquefied gas storage section, a liquefied gas outlet pipe for outletting the liquefied gas stored in the second liquefied gas storage section, and a drip nozzle provided at the tip of the liquefied gas outlet pipe, wherein the liquefied gas introduction pipe is bifurcated in the first liquefied gas storage section, one of which is an upper branch pipe extending upward and the other is a lower branch pipe extending downward, and an upper resistance section and a lower resistance section are provided at the outlet openings of both of the first liquefied gas and the second liquefied gas. The liquefied gas supplied from the upper branch pipe through the upper resistance part is stored in the gas storage part, and the lower branch pipe is cooled by the stored liquefied gas. The liquefied gas supplied from the lower branch pipe through the lower resistance part is supplied to the second liquefied gas storage part from the lower end of the first liquefied gas storage part. The second liquefied gas storage part is provided with a float that moves up and down according to the liquid level position of the liquefied gas inside and controls the opening and closing of the lower end of the first liquefied gas storage part and the liquefied gas outlet pipe. The liquefied gas outlet pipe has an opening that is provided at a position higher than the bottom surface of the second liquefied gas storage part.

The second aspect of the present invention is the first aspect, characterized in that the lower branch pipe is formed in a spiral shape.

The third invention of the present invention is characterized in that, in the first or second invention, two floats are provided in the second liquefied gas storage section, one of which controls the opening and closing of the lower end of the first liquefied gas storage section, and the other of which controls the opening and closing of the liquefied gas outlet tube.

The fourth invention of the present invention is characterized in that in the first or second invention, one float is provided in the second liquefied gas storage section, and the one float controls both the opening and closing of the lower end of the first liquefied gas storage section and the liquefied gas outlet tube.

The fifth aspect of the present invention is any one of the first to fourth aspects, characterized in that the drip nozzle is equipped with a screen for turning the liquefied gas into a mist.

The sixth aspect of the present invention is any one of the first to fourth aspects, characterized in that the drip nozzle is provided with a throttle for forming droplets of liquefied gas.

The seventh aspect of the present invention is a spray freezing device that sprays and freezes a target raw material using the mist-like liquefied gas generated from the drip nozzle in the fifth aspect of the present invention, and is characterized in that it comprises a spray nozzle for spraying the target raw material, a cooling jacket surrounding the spraying location of the spray nozzle, and a frozen material removal valve for recovering the frozen material formed by freezing the target raw material with the liquefied gas, and that exhaust gases discharged from the first liquefied gas storage unit and the second liquefied gas storage unit are introduced into the cooling jacket.

The eighth aspect of the present invention is a liquefied gas supply method using the liquefied gas supply device according to the first to sixth aspects, in which liquefied gas is supplied from a liquefied gas supply source through the liquefied gas inlet pipe, the first liquefied gas storage section, the second liquefied gas storage section, and the liquefied gas outlet pipe from the drip nozzle, and the liquefied gas is supplied to the second liquefied gas storage section in a reduced pressure state by passing through a lower resistance section provided in the lower branch pipe of the liquefied gas inlet pipe inside the first liquefied gas storage section, and the pressure of the liquefied gas is further reduced by being stored inside the second liquefied gas storage section, and the liquefied gas with the reduced pressure is supplied from the drip nozzle via the liquefied gas outlet pipe.

The ninth aspect of the present invention is a method for spray-freezing a target material using the spray-freezing device of the seventh aspect of the present invention, characterized in that the spray area is pre-cooled by mist-like liquefied gas generated from the drip nozzle, the target material is sprayed into the pre-cooled spray area by the spray nozzle, the sprayed target material is frozen, and the resulting frozen product is collected.

According to the liquefied gas supply device and supply method of the present invention, the pressure of the liquefied gas can be reduced by a resistance section and a storage section provided in the middle of the supply path, so that it is possible to supply liquefied gas at low temperature and pressure with a simple structure without using expensive equipment. In addition, according to the spray freezing device and spray freezing method using the above device and method, an object can be efficiently cooled using low-temperature, low-pressure liquefied gas.

FIG. 2 is a diagram showing a state where liquefied gas supply is started in the liquefied gas supply device according to the first embodiment of the present invention. FIG. 2 is a diagram showing an intermediate state in the liquefied gas supply device of the first embodiment. 1 is a diagram showing a state in which the supply of liquefied gas is stopped in the liquefied gas supply device of the first embodiment. FIG. 3 is a diagram showing the configuration of a liquefied gas inlet pipe and a liquefied gas supply pipe in the liquefied gas supply device of the first embodiment. FIG. FIG. 11 is a diagram showing a state where liquefied gas supply is started in the liquefied gas supply device according to the second embodiment of the present invention. FIG. 11 is a diagram showing an intermediate state in the liquefied gas supply device of the second embodiment. 11 is a diagram showing a state in which the supply of liquefied gas is stopped in the liquefied gas supply device of the second embodiment. FIG. FIG. 2 is a diagram showing an example of a drip nozzle in the liquefied gas supply device. 11A and 11B are diagrams showing another example of a drip nozzle in the liquefied gas supply device. FIG. 2 is a diagram showing a spray freezing device using the liquefied gas supply device.

Figure 1 shows a liquefied gas supply device 1 according to a first embodiment of the present invention. The liquefied gas supply device 1 is generally composed of a liquefied gas supply source 2, a liquefied gas inlet pipe 3, a first liquefied gas storage section 4, a second liquefied gas storage section 5, a liquefied gas outlet pipe 6, and a drip nozzle 7.

As shown in FIG. 2, the liquefied gas supply source 2 is a source of liquefied gas (such as liquid nitrogen) that is connected to a liquefied gas storage container such as a large-capacity tank or a small-capacity cylinder.

The liquefied gas introduction pipe 3 is a pipe that supplies the liquefied gas supplied from the liquefied gas supply source 2 to the first liquefied gas storage section 4 described below. As shown in FIG. 2, the liquefied gas introduction pipe 3 is inserted into the first liquefied gas storage section 4 and is bifurcated inside the first liquefied gas storage section 4. One of the bifurcations is an upper branch pipe 8 that extends upward and is formed in a straight line, and an upper resistance section 9 made of sintered metal is provided at its outlet opening. The upper surface of the upper resistance section 9 is sealed. Therefore, the liquefied gas flowing through the upper branch pipe 8 is supplied to the first liquefied gas storage section 4 through the side of the upper resistance section 9.

The other of the two branches is the lower branch pipe 10 that extends downward and is formed in a spiral shape, and its outlet opening is provided with a lower resistance section 11 made of sintered metal, similar to the upper branch pipe 8. Therefore, the liquefied gas flowing through the lower branch pipe 10 is supplied to the first liquefied gas storage section 4 through the lower resistance section 11.

The first liquefied gas storage section 4 is a cylindrical tubular member that supplies the liquefied gas supplied from the liquefied gas inlet pipe 3 to the second liquefied gas storage section 5 described below, and is open at the lower end. As shown in FIG. 2, the first liquefied gas storage section 4 is divided into two sections, upper and lower, by a partition section 12, and above the partition section 12, the liquefied gas inlet pipe 3 branches into an upper branch pipe 8 and a lower branch pipe 10. The spiral portion of the lower branch pipe 10 is formed above the partition section 12, the outlet opening side penetrates the partition section 12, and the lower resistance section 11 is provided below the partition section 12.

The liquefied gas is first supplied in gaseous form from both the upper resistance section 9 and the lower resistance section 11 to the first liquefied gas storage section 4. When the surroundings are cooled by the gas, the liquid phase portion of the liquefied gas is discharged below the partition section 12 through the lower resistance section 11, and the gas phase portion is discharged above the partition section 12 through the upper resistance section 9. When the surroundings are then sufficiently cooled, the liquid phase portion is also discharged above the partition section 12 through the upper resistance section 9, and accumulates around the lower branch pipe 10 as liquefied gas.

In this way, the lower branch pipe 10 is cooled by the liquefied gas that accumulates above the partition 12. Because the lower branch pipe 10 is formed in a spiral shape, the surface area in contact with the liquefied gas that accumulates above the partition 12 is large, so the liquefied gas flowing through the lower branch pipe 10 is cooled sufficiently and does not vaporize. In addition, a portion of the liquefied gas supplied to the first liquefied gas storage section 4 vaporizes above the partition 12. The vaporized gas is discharged to the outside while the pressure is appropriately adjusted by a pressure-maintaining mechanism 13, such as a pressure-maintaining valve, provided at the top.

On the other hand, below the partition 12, liquefied gas is supplied to the first liquefied gas storage section 4 through the lower resistance section 11. The supplied liquefied gas flows down from the lower end of the first liquefied gas storage section 4 to the second liquefied gas storage section 5.

The second liquefied gas storage section 5 is a rectangular parallelepiped tank-like member that stores the liquefied gas supplied from the first liquefied gas storage section 4 and delivers it to the liquefied gas outlet pipe 6 described below. The part of the first liquefied gas storage section 4 below the partition section 12 is inserted into the upper part of the second liquefied gas storage section 5.

In addition, a float that moves up and down depending on the liquid level of the stored liquefied gas is provided in the second liquefied gas storage section 5, and the opening and closing of the lower end of the first liquefied gas storage section 4 and the liquefied gas outlet pipe 6 are controlled depending on the position of the float. In addition, a pressure maintaining mechanism 14 such as a pressure maintaining valve is provided in the upper part of the second liquefied gas storage section 5, and gas that has evaporated inside and accumulated in the upper part is discharged to the outside while the pressure is appropriately adjusted.

The liquefied gas outlet pipe 6 is a pipe that supplies the liquefied gas supplied from the second liquefied gas storage section 5 to the drip nozzle 7 described below. The opening of the liquefied gas outlet pipe 6 is located at a position higher than the bottom surface of the second liquefied gas storage section 5 (see Figures 1 and 3).

As a first embodiment, the float in the second liquefied gas storage section 5 is provided with a supply float 15 that controls the opening and closing of the lower end of the first liquefied gas storage section 4, and a drip float 16 that controls the opening and closing of the liquefied gas outlet pipe 6, as shown in FIG. 1.

Immediately after the supply of liquefied gas into the second liquefied gas storage section 5 begins, as shown in FIG. 1(a), only the supply float 15 is above the liquid surface, the first liquefied gas storage section 4 is open, and the liquefied gas outlet pipe 6 is closed by the drip float 16. Therefore, only the liquefied gas is stored inside the second liquefied gas storage section 5, and the liquefied gas is not discharged to the liquefied gas outlet pipe 6.

As the supply of liquefied gas progresses and the amount of gas stored inside the second liquefied gas storage section 5 gradually increases, as shown in FIG. 1(b), the supply float 15 and the drip float 16 are both above the liquid surface, and the first liquefied gas storage section 4 and the liquefied gas outlet pipe 6 are both open. Therefore, while liquefied gas is stored inside the second liquefied gas storage section 5, liquefied gas is discharged to the liquefied gas outlet pipe 6.

When the amount of gas stored inside the second liquefied gas storage section 5 increases further, as shown in FIG. 1(c), the supply float 15 blocks the outlet opening of the first liquefied gas storage section 4 while both the supply float 15 and the drip float 16 are above the liquid surface. This closes the first liquefied gas storage section 4 and leaves the liquefied gas outlet pipe 6 open. As a result, storage of liquefied gas inside the second liquefied gas storage section 5 stops, and only liquefied gas is discharged to the liquefied gas outlet pipe 6.

As the liquefied gas continues to be discharged, the liquid level drops and the drip float 16 closes the liquefied gas discharge pipe 6. This results in the same state as in FIG. 1(a) above, where again liquefied gas is only stored inside the second liquefied gas storage section 5 and is no longer discharged to the liquefied gas discharge pipe 6. From this point on, the above operations are repeated. The amount of liquefied gas stored can be adjusted by the position of the outlet opening of the first liquefied gas storage section 4 and the position of the opening of the liquefied gas discharge pipe 6. In addition, because the float moves relatively slowly, the impact of fluctuations in the supply pressure of the liquefied gas on the object to be cooled can be reduced.

Figure 3 shows a liquefied gas supply device 1a according to a second embodiment of the present invention. In this second embodiment, only one float, a supply and drip float 17, is provided. In this embodiment, the outlet opening of the first liquefied gas storage section 4 and the opening of the liquefied gas outlet pipe 6 are aligned in a straight line. Other than that, it is the same as the liquefied gas supply device 1 according to the first embodiment.

In the second embodiment described above, immediately after the supply of liquefied gas into the second liquefied gas storage section 5 is started, as shown in FIG. 3(a), the supply and drip float 17 closes the liquefied gas outlet pipe 6, and the first liquefied gas storage section 4 is open. Therefore, only the liquefied gas is stored inside the second liquefied gas storage section 5, and the liquefied gas is not discharged to the liquefied gas outlet pipe 6.

As the supply of liquefied gas progresses and the amount of gas stored inside the second liquefied gas storage section 5 gradually increases, the supply and drip float 17 is above the liquid surface and positioned halfway between the first liquefied gas storage section 4 and the liquefied gas outlet pipe 6, as shown in FIG. 3(b), and both the first liquefied gas storage section 4 and the liquefied gas outlet pipe 6 are opened. Therefore, while the liquefied gas is stored inside the second liquefied gas storage section 5, the liquefied gas is discharged to the liquefied gas outlet pipe 6.

When the amount of gas stored inside the second liquefied gas storage section 5 increases further, as shown in FIG. 3(c), the supply and drip float 17 is above the liquid surface and blocks the outlet opening of the first liquefied gas storage section 4. Then, the first liquefied gas storage section 4 is closed and the liquefied gas outlet pipe 6 is opened. Therefore, the storage of liquefied gas inside the second liquefied gas storage section 5 stops, and only the outlet of liquefied gas to the liquefied gas outlet pipe 6 is performed.

As the liquefied gas continues to be discharged, the liquid level drops and the supply/drip float 17 closes the liquefied gas discharge pipe 6. This returns the system to the same state as in Figure 3(a) above, whereby liquefied gas is once again only stored inside the second liquefied gas storage section 5 and is no longer discharged to the liquefied gas discharge pipe 6. From this point on, the above operations are repeated.

The drip nozzle 7 is a nozzle for changing the liquefied gas supplied from the liquefied gas outlet pipe 6 into various shapes and releasing it to the outside, and is provided at the tip of the liquefied gas outlet pipe 6. As an example, the drip nozzle 7 is provided with a screen 18 as shown in FIG. 4(a), and the released liquefied gas can be made into a mist. By turning the liquefied gas into a mist, it is possible to freeze the target object while maintaining its shape, for example, by freezing the surface of a soft serve ice cream. As another example, as shown in FIG. 4(b), it is provided with a straight pipe with an outer cylinder having a constriction 19, and the released liquefied gas can be made into droplets. By turning the liquefied gas into droplets, it is possible to cool canned drinks and the like by dripping them.

Using the liquefied gas supply device 1, 1a configured as described above, liquefied gas is supplied as follows.

First, liquefied gas is supplied from the liquefied gas supply source 2 to the liquefied gas introduction pipe 3. In the liquefied gas introduction pipe 3, the liquefied gas is split into two branches, an upper branch pipe 8 and a lower branch pipe 10, and then supplied. At this time, the holding pressure of the liquefied gas inside the pipe (first holding pressure) is set to 10-50% of the pressure when the liquefied gas is supplied. The liquefied gas released from the outlet opening of the upper branch pipe 8 passes through the upper resistance section 9 and is stored above the partition section 12 of the first liquefied gas storage section 4. A part of the stored liquefied gas is vaporized and discharged to the outside via the pressure holding mechanism 13.

On the other hand, the liquefied gas discharged from the outlet opening of the lower branch pipe 10 passes through the lower resistance section 11 and flows downward from the lower end of the first liquefied gas storage section 4 to the second liquefied gas storage section 5 below the partition section 12. At this time, the holding pressure of the liquefied gas further decreases to 10 to 50% of the first holding pressure. In addition, the pressure of the bifurcated liquefied gas decreases by passing through the upper resistance section 9 or the lower resistance section 11 (for example, 0.19 to 0.15 MPa).

The liquefied gas that flows down to the second liquefied gas storage section 5 is stored in the second liquefied gas storage section 5, and is supplied to the liquefied gas outlet pipe 6 when the opening of the liquefied gas outlet pipe 6 is opened by opening and closing control using a float installed inside. At this time, the pressure of the liquefied gas is further reduced (for example, 0.1 to 0.05 MPa) by being stored in the second liquefied gas storage section 5. Therefore, it is possible to supply low-pressure liquefied gas while maintaining a low temperature.

In addition, in the second liquefied gas storage section 5, a portion of the stored liquefied gas is vaporized and discharged to the outside via the pressure retention mechanism 14. On the other hand, the liquefied gas supplied to the liquefied gas outlet pipe 6 is discharged to the outside in the form of mist or droplets from the drip nozzle 7 provided at the tip.

Figure 5 shows a spray freezing device 20 that uses the liquefied gas supply device 1a. In addition to the liquefied gas supply device 1a, the spray freezing device 20 is equipped with a control valve 21, a temperature regulator 22, a spray nozzle 23, a cooling jacket 24, a frozen material removal valve 25, and an exhaust damper 26.

The control valve 21 is an on-off valve provided in the liquefied gas outlet pipe 6 of the liquefied gas supply device 1a. The control valve 21 is linked to a temperature regulator 22, and controls the release of liquefied gas according to the temperature of the spray area (the area surrounded by the cooling jacket 24 described later).

The spray nozzle 23 is a nozzle for spraying the target raw material for spray freezing in the spray area. The spray nozzle 23 is inserted into the spray area through a nozzle gate 27 provided in the cooling jacket 24 described later only when spraying the target raw material.

The cooling jacket 24 forms a spray area (area for spray-freezing the target raw material). Vaporized liquefied gas (gas phase portion) discharged from the pressure-maintaining mechanism 13 and the pressure-maintaining mechanism 14 is supplied into the cooling jacket 24 to maintain a cooled state. The cooling jacket 24 is covered with a cooling material (not shown) and is insulated from the outside air temperature. The cooling jacket 24 is also provided with a nozzle gate 27 for inserting the spray nozzle 23 into the spray area.

The frozen material removal valve 25 is a valve for recovering the frozen material of the target raw material at the bottom of the cooling jacket 24. The frozen material is discharged to the outside only when the valve is opened.

The exhaust damper 26 is used to exhaust the liquefied gas vaporized in the spray area, and the outside of the exhaust damper 26 is open to the atmosphere.

Using the spray freezing device 20 configured as described above, spray freezing of the target raw material is carried out as follows.

First, the entire spray freezing device 20 is pre-cooled. In the liquefied gas supply device 1a, when liquefied gas is supplied to the liquefied gas outlet pipe 6, the control valve 21 and temperature regulator 22 are activated, and the liquefied gas is released in the form of a low-pressure, low-temperature mist from the screen 18 of the drip nozzle 7, cooling the entire device. When the entire device has been cooled to a specified temperature (for example, below -40°C), the control valve 21 is closed and pre-cooling is completed. At this time, the liquefied gas vaporized in the spray area is exhausted to the outside through the exhaust damper 26.

Next, the spray nozzle 23 is inserted into the spray area through the nozzle gate 27, and the target raw material is sprayed. Since the inside of the device has been cooled to a specified temperature by the pre-cooling described above, the target raw material freezes instantly when sprayed, and falls to the bottom as a frozen mass. In addition, the cooling jacket 24 is cooled by the gas phase discharged from the pressure retention mechanism 13 and the pressure retention mechanism 14, so the frozen mass does not adhere to it. When a certain amount of frozen mass has accumulated at the bottom of the spray area, the frozen mass removal valve 25 is opened and the frozen mass is collected.

In addition, in the spray freezing of the target raw material, the liquefied gas is supplied in the form of a low-pressure, low-temperature mist through the screen 18. Therefore, the effect of the self-pressure of the liquefied gas when spraying on the target raw material is small. Therefore, when the fine particles are frozen, they fall to the bottom without being entrained by the vaporized liquefied gas. This prevents the fine particles from adhering to the wall surface of the cooling jacket 24 or being entrained in the gas phase of the liquefied gas and being discharged from the exhaust damper 26.

According to the liquefied gas supply device and spray freezing device in each of the above embodiments, by providing a first liquefied gas storage section and a second liquefied gas storage section, the gas-liquid separation mechanism of the liquefied gas is set in two stages, and the pressure can be reduced in stages. In addition, by controlling the opening and closing of the inlet and outlet in the second liquefied gas storage section using a float system, it is possible to continuously supply liquefied gas at low pressure.

In each of the above embodiments, various liquefied gases, including liquid nitrogen, can be used as the liquefied gas depending on the usage environment and the properties of the object.

1, 1a... liquefied gas supply device, 2... liquefied gas supply source, 3... liquefied gas inlet pipe, 4... first liquefied gas storage section, 5... second liquefied gas storage section, 6... liquefied gas outlet pipe, 7... dripping nozzle, 8... upper branch pipe, 9... upper resistance section, 10... lower branch pipe, 11... lower resistance section, 12... partition section, 13, 14... pressure retention mechanism, 15... supply float, 16... dripping float, 17... supply and dripping float, 18... screen, 19... throttle, 20... spray freezing device, 21... control valve, 22... temperature regulator, 23... spray nozzle, 24... cooling jacket, 25... frozen material removal valve, 26... exhaust damper, 27... nozzle gate

Claims (9)

a first liquefied gas storage section into which liquefied gas is introduced from a liquefied gas supply source through a liquefied gas introduction pipe;
a second liquefied gas storage section to which liquefied gas is supplied from the first liquefied gas storage section;
a liquefied gas outlet pipe for outletting the liquefied gas stored in the second liquefied gas storage section;
a dripping nozzle provided at the tip of the liquefied gas outlet pipe,
the liquefied gas introduction pipe is bifurcated in the first liquefied gas storage section, one of which is an upper branch pipe extending upward and the other is a lower branch pipe extending downward, both of which are provided with upper resistance portions and lower resistance portions at their outlet openings,
In the first liquefied gas storage section, the liquefied gas supplied from the upper branch pipe through the upper resistance section is stored, the lower branch pipe is cooled by the stored liquefied gas, and the liquefied gas supplied from the lower branch pipe through the lower resistance section is supplied to the second liquefied gas storage section from a lower end of the first liquefied gas storage section,
The second liquefied gas storage section is provided with a float that moves up and down according to the liquid level of the liquefied gas therein and controls the opening and closing of the lower end of the first liquefied gas storage section and the liquefied gas outlet pipe,
A liquefied gas supply device, characterized in that an opening of the liquefied gas outlet pipe is provided at a position higher than a bottom surface of the second liquefied gas storage section. The liquefied gas supply device according to claim 1, characterized in that the lower branch pipe is formed in a spiral shape. The liquefied gas supply device according to claim 1 or 2, characterized in that two floats are provided in the second liquefied gas storage section, one of which controls the opening and closing of the lower end of the first liquefied gas storage section, and the other of which controls the opening and closing of the liquefied gas outlet pipe. The liquefied gas supply device according to claim 1 or 2, characterized in that one float is provided in the second liquefied gas storage section, and the one float controls both the opening and closing of the lower end of the first liquefied gas storage section and the liquefied gas outlet pipe. The liquefied gas supply device according to any one of claims 1 to 4, characterized in that the drip nozzle is equipped with a screen for turning the liquefied gas into a mist. The liquefied gas supply device according to any one of claims 1 to 4, characterized in that the drip nozzle is provided with a throttle for forming the liquefied gas into droplets. A spray freezing apparatus for spray-freezing a target raw material using the mist-like liquefied gas generated from the drip nozzle, using the liquefied gas supply apparatus according to claim 5,
A spray nozzle for spraying the target raw material;
a cooling jacket surrounding the spray location of the spray nozzle;
a frozen material removal valve for recovering the frozen material obtained by freezing the target material by the liquefied gas;
A spray freezing apparatus, characterized in that exhaust gases discharged from the first liquefied gas storage section and the second liquefied gas storage section are introduced into the cooling jacket. A liquefied gas supply method for supplying liquefied gas using the liquefied gas supply device according to any one of claims 1 to 6,
liquefied gas is supplied from a liquefied gas supply source through the liquefied gas inlet pipe, the first liquefied gas storage section, the second liquefied gas storage section, and the liquefied gas outlet pipe to the drip nozzle;
In the first liquefied gas storage section, the liquefied gas passes through a lower resistance section provided in the lower branch pipe of the liquefied gas introduction pipe, and is supplied to the second liquefied gas storage section in a state where the pressure of the liquefied gas is reduced,
By storing the liquefied gas inside the second liquefied gas storage section, the pressure of the liquefied gas is further reduced,
The liquefied gas supply method is characterized in that the liquefied gas whose pressure has been reduced is supplied from a drip nozzle via the liquefied gas outlet pipe. A method for spray freezing a target material using the spray freezing device according to claim 7,
A spray area is pre-cooled by the mist-like liquefied gas generated from the drip nozzle,
Spraying the target raw material into the pre-cooled spray area with a spray nozzle;
A spray freezing method comprising the steps of: freezing a sprayed target material; and recovering the resulting frozen material.

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