JP2002340484A - Evaporator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an evaporator, small in size, high in performance and excellent in temperature stability, by a method wherein a characteristic that the evaporator can supply a gas at a stabilized temperature while utilizing the high heat exchanging efficiency of a heat exchanger utilizing steam and the temperature stability of evaporated gas in a heat exchanger utilizing hot-water are combined. SOLUTION: A first constitution is provided with a main heat exchanging tank and a heat exchanging tank for regulating temperature, which are different in an evaporated gas temperature, to join and mix the evaporated gas from both heat exchanging tanks whereby temperature regulation is effected. A second constitution is provided with a first heat exchanger in a hot-water layer, a second heat exchanger in a steam layer and a third heat exchanger in the hot-water layer which are formed so as to conduct gas to flow in this sequence whereby the evaporator, utilizing the highness of the heat exchanging efficiency due to steam and the excellency of temperature stability due to hot-water, can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an evaporator for vaporizing a low-temperature liquefied gas, and more particularly, to an evaporator capable of stabilizing the temperature of a vaporized gas.

[0002]

2. Description of the Related Art Generally, in a facility using a relatively large amount of gas, for example, a gas such as nitrogen, oxygen, or argon, a low-temperature liquefied gas such as liquid nitrogen, liquid oxygen, or liquid argon filled in a low-temperature liquefied gas storage tank is supplied. It is used by vaporizing it with an evaporator. Examples of the evaporator for vaporizing low-temperature liquefied gas include an air-heated evaporator using the atmosphere as a heat medium, a hot water evaporator using hot water as a heat medium, and a steam evaporator using high-temperature and high-pressure steam as a heat medium. Used.

An air-heated evaporator, which is a general-purpose evaporator, uses aluminum having a high thermal conductivity as a material of a heat exchanger.
The structure is a combination of multiple tubes according to the required heat exchange capacity. Since the low-temperature liquefied gas flowing in the pipes is vaporized by performing heat exchange with the atmosphere through the fins, the heat exchange capacity of the air-heated evaporator is determined by the area of the heat exchange fins, Adjusted by length.

The air-heated evaporator vaporizes a low-temperature liquefied gas by heat exchange with the atmosphere, and therefore does not require a heat source and is widely used. However, when the atmospheric temperature of the installation location is low, the heat exchange capacity is reduced, and there is a problem that the capacity is affected by the atmospheric temperature. Also,
Increasing or lengthening the number of pipes to increase the heat exchange capacity causes the evaporator itself to become large,
There is a problem that installation space is required as compared with other types of evaporators.

[0005] In the steam type evaporator, a pipe for heat exchange is hermetically arranged in a closed vessel into which steam is introduced, a low-temperature liquefied gas is flowed into this pipe, and steam is introduced into the vessel. The low-temperature liquefied gas is vaporized by heat exchange. As steam, in general,
A steam of 0.3 MPa and 120 ° C. is used.
This steam type evaporator has a feature that the heat exchange efficiency is high, and if steam can be supplied, the installation place is not limited to the environment, and the apparatus is compact. However, there is a problem that the temperature difference between the steam before and after the heat exchange is large, and the temperature control range of the vaporized gas is widened.

In the hot water evaporator, a pipe for heat exchange is hermetically disposed in a vessel containing hot water at a predetermined temperature, and a low-temperature liquefied gas is flowed through the pipe to exchange heat. The replenishment of the heat deprived from the hot water by the heat exchange is generally performed by a heater. This hot-water evaporator has a feature that the temperature control range of the vaporized gas can be narrowed and is stable. However, there is a problem that the container itself is larger than the steam type evaporator, and the operating weight is increased, so that attention must be paid to the installation location.

[0007]

As described above, in the conventional evaporator, there is no suitable evaporator capable of supplying gas at a stable temperature, and a large amount of gas having a substantially constant temperature is supplied. Had to use a large hot water evaporator. For this reason, for example, when the application of the supplied gas is a spot gas use, such as an airtightness test of a gas tank or the like, and a large amount of gas is required, and further, when a gas supply close to the atmospheric temperature is desired, The steam-type evaporator, which has a relatively high supply gas temperature and difficult to control the gas temperature, is rarely used.A large air-temperature evaporator or hot-water evaporator is transported to the site, and the evaporator assembly and The gas supply is started after connecting the pipes on site.

Therefore, not only is space required for installing an evaporator on site, but also a considerable amount of time is required from the loading of equipment to the start of gas supply, and the costs required for transporting and assembling equipment are also reduced. It was enormous.

Therefore, the present invention can supply gas at a stable temperature while utilizing the high heat exchange efficiency of a heat exchanger using steam, and furthermore, vaporizes gas in a heat exchanger using hot water. An object of the present invention is to provide a small-sized, high-performance evaporator having more excellent temperature stability by combining gas temperature stability.

[0010]

According to a first aspect of the present invention, there is provided an evaporator in which a low-temperature liquefied gas is heated and vaporized by exchanging heat with a heat medium. A main heat exchange tank containing a heat exchanger in which the low-temperature liquefied gas is introduced in a vessel into which the heat medium is introduced, and a heat in which a part of the low-temperature liquefied gas is introduced into the vessel into which the heat medium is introduced. A heat exchange tank for temperature control containing an exchanger, a low-temperature liquefied gas introduction path for introducing a low-temperature liquefied gas into the heat exchanger of the main heat exchange tank, a branch from the low-temperature liquefied gas introduction path, and a flow control valve. A low-temperature liquefied gas introduction path for introducing a low-temperature liquefied gas into the heat exchanger of the temperature-adjustment heat exchange tank, a vaporized gas derivation path for leading out gas vaporized by the heat exchanger of the main heat exchange tank, Deriving vaporized gas with heat exchanger of heat exchange tank for temperature control And the vaporized gas derivation path for temperature control that,
A gas supply path for mixing and mixing the gas in the vaporized gas derivation path and the gas in the temperature control vaporized gas derivation path and supplying the gas to a gas use destination; and a temperature measuring means for measuring the temperature of the supply gas flowing through the gas supply path And control means for controlling opening and closing of a flow control valve of the low-temperature liquefied gas introduction path for temperature control based on the temperature measured by the temperature measurement means. The exchange capacity is set to be different from the heat exchange capacity of the main heat exchange tank.

A second configuration of the evaporator of the present invention is an evaporator that heats and vaporizes a low-temperature liquefied gas by exchanging heat with a heat medium, wherein the evaporator has a steam layer and a heat layer as a heat medium. A first heat exchanger disposed in the hot water layer and into which the low-temperature liquefied gas is introduced, and a first heat exchanger disposed in the steam layer in at least one heat exchange tank having a hot water layer. The second heat exchanger into which the gas after heat exchange is introduced is housed, and the third heat exchanger which is disposed in the hot water layer and into which the gas after heat exchange is introduced in the second heat exchanger is housed. It is characterized by:

Further, in the above structure, the temperature of the gas after the heat exchange in the second heat exchanger is set higher than the set temperature of the gas led out from the evaporator, and the heat in the third heat exchanger is The temperature of the gas after exchange is set lower than the temperature of the gas after heat exchange in the second heat exchanger. A temperature measuring means for measuring a temperature of the gas derived from the evaporator; a boiler for supplying steam into the heat exchange tank; and a boiler for supplying heat to the heat exchange tank based on the gas temperature measured by the temperature measuring means. Steam supply amount adjusting means for adjusting the amount of steam supplied to the apparatus.

[0013]

FIG. 1 is a system diagram showing a first embodiment of an evaporator according to the present invention. This evaporator has a main heat exchange tank 1
0 and the temperature control heat exchange tank 20 are installed in parallel, and the gas vaporized in the main heat exchange tank 10 and the temperature control heat exchange tank 2
The gas at a predetermined temperature is supplied by appropriately mixing the gas vaporized at 0.

The two heat exchange tanks 10 and 20 contain heat exchangers 12 and 22 into which low-temperature liquefied gas is introduced, respectively, in metal sealed containers 11 and 21 having a heat insulating structure. In 11 and 21, steam introduction pipes 13 and 23 for introducing steam generated in the boiler B into the container as a heat medium, and water generated by steam condensation due to heat exchange are extracted from the container and returned to the boiler. Drain 14,
24 are provided respectively.

A low-temperature liquefied gas introduction path 15 for introducing a low-temperature liquefied gas supplied from a low-temperature liquefied gas storage tank C or the like is connected to a lower inlet of a heat exchanger 12 provided in the main heat exchange tank 10. The upper outlet is connected to a vaporized gas deriving path 16 for deriving gas vaporized in the heat exchanger 12. On the other hand, a low-temperature liquefied gas introduction path 25 for temperature regulation branched from the low-temperature liquefied gas introduction path 15 is connected to a lower inlet portion of the heat exchanger 22 provided in the heat exchange tank 20 for temperature regulation via a flow control valve 27. In addition, a temperature-regulated vaporized gas deriving path 26 for deriving gas vaporized in the heat exchanger 22 is connected to the upper outlet portion.

The vaporized gas outlet path 16 and the temperature controlled vaporized gas outlet path 26 merge to form a gas supply path 17,
Gas is supplied to the user's gas use facility through the gas supply path 17. The gas supply path 17 is provided with a temperature indicating controller (TIC) 31 which is a means for measuring the temperature of the supplied gas. The temperature indicating controller 31 controls the opening and closing of the flow control valve 27 based on the indicated value and the measured value, and controls the temperature of the low-temperature liquefied gas introduction path 25 for temperature control.
To adjust the amount of low-temperature liquefied gas introduced into the heat exchanger 22 of the heat exchange tank 20 for temperature control.

Various conditions such as the volumes of the vessels 11 and 21 in the heat exchange tanks 10 and 20, the shapes of the heat exchangers 12 and 22, and the amount of introduced steam are determined by the supply gas amount (evaporation amount) required for the evaporator. ) And the temperature range of the supply gas, etc., but by making the heat exchange capacity of the main heat exchange tank 10 and the heat exchange capacity of the heat exchange tank 20 for temperature control different from each other, Adjustment can be performed more easily. The heat exchange capacity in each heat exchange tank is, for example, by increasing the heat exchange area of the heat exchanger, reducing the flow rate of gas flowing in the heat exchanger, or increasing the amount of introduced steam, Heat exchange capacity can be increased.

The steam introduction pipes 13 and 23 are provided with control valves 13V and 23V, respectively, for adjusting the amount of introduced steam. Is continuously introduced into each of the containers 11 and 21.

In order to supply a gas at a predetermined temperature at a predetermined flow rate using the evaporator thus formed, first, each container 1
A predetermined amount of steam at a predetermined temperature and pressure is introduced into each of the first and second units. At this time, the amount of steam introduced into each of the containers 11 and 21 may be set in accordance with the amount of evaporation of the low-temperature liquefied gas and the temperature of the supply gas.
The temperature of the gas derived from 0 is set higher than the set temperature of the supply gas, and the temperature of the gas derived from the temperature control heat exchange tank 20 is set lower than the set temperature of the supply gas.

In this state, the supply of the low-temperature liquefied gas from the low-temperature liquefied gas storage tank C or the like is started. The supply ratio of each low-temperature liquefied gas to the main heat exchange tank 10 and the temperature control heat exchange tank 20 is controlled by the temperature indicating controller 31. That is, by adjusting the mixing ratio of the gas (high-temperature gas) having a temperature higher than the set temperature derived from the main heat exchange tank 10 and the gas having a temperature lower than the set temperature derived from the heat exchange tank 20 for temperature control,
The temperature of the feed gas can be adjusted to a desired temperature.

For example, when the temperature of the supply gas measured by the temperature indicating controller 31 exceeds the set temperature, the flow control valve 27 is operated in the opening direction. As a result, the supply amount of the low-temperature liquefied gas to the temperature control heat exchange tank 20 increases, and the supply amount of the low-temperature liquefied gas to the main heat exchange tank 10 decreases.
Since the flow rate of the high-temperature gas vaporized in the step decreases and the flow rate of the low-temperature gas vaporized in the temperature control heat exchange tank 20 increases,
The temperature of the supply gas in which the two are mixed will decrease. Similarly, when the measured temperature of the supply gas falls below the set temperature,
By operating the flow control valve 27 in the closing direction, the temperature of the supply gas can be increased.

It should be noted that even in the evaporator having the same configuration, by adjusting the amount of steam introduced into each of the containers 11 and 21, the temperature of the gas derived from the main heat exchange tank 10 is made higher than the set temperature of the supply gas. The temperature of the gas derived from the temperature control heat exchange tank 20 can be set higher than the set temperature of the supply gas. In this case, when the measured temperature of the supply gas exceeds the set temperature, the flow control valve 27 is operated in the closing direction to reduce the mixing ratio of the high-temperature gas from the heat exchange tank 20 for temperature control. In the above description, a predetermined amount of steam is continuously introduced into each of the containers 11 and 21.
The temperature at appropriate positions of 0 and 20 and the temperature of each derived gas are detected, and the control valves 13V and 23V are opened / closed based on the detected temperatures to intermittently introduce steam or adjust the amount of introduced steam. You may.

As described above, even when steam is used as the heat medium, the mixing ratio between the gas derived from the main heat exchange vessel 10 and the gas derived from the temperature control heat exchange vessel 20 is adjusted. It is possible to control the temperature of the supply gas within a set temperature range. By using steam, it is possible to reduce the size of the evaporator by taking advantage of its high heat exchange rate, and form it as an evaporator unit including a boiler. The gas supply to the gas-using equipment can be started in a short time.

In this embodiment, steam is used as a heat medium for vaporizing the low-temperature liquefied gas and heating it. However, steam and hot water may coexist in each vessel. In this case, heating of the hot water can be performed by steam, but heating by a heater may be used together. Furthermore, when stability of the supply gas temperature is required rather than the size of the evaporator, hot water can be used as the heat medium.

FIG. 2 is a system diagram showing a second embodiment of the evaporator of the present invention. This evaporator is a small-sized evaporator having excellent temperature stability, taking advantage of both the hot water evaporator and the steam evaporator.

The evaporator shown in this embodiment is a combination of a first heat exchange tank 51 using steam and hot water as a heat medium and a second heat exchange tank 52 using steam as a heat medium. Both heat exchange tanks 51 and 52 are provided with first to third heat exchangers 53 and 5 in which low-temperature liquefied gas is introduced into metal closed containers 51a and 52a having a heat insulating structure, as in the above-described embodiment.
4 and 55, respectively, and a steam introduction pipe 5 for introducing steam generated by the boiler B into the container.
6, 57 and drains 58, 59 for extracting water generated by condensation of steam due to heat exchange from the container and returning it to the boiler.
Are provided respectively.

Each of the heat exchangers is provided in series in the order of the first heat exchanger 53, the second heat exchanger 54, and the third heat exchanger 55 in the gas flow direction. Heat exchanger 53
The third heat exchanger 55 has a lower part located in the hot water layer W of the first heat exchange tank 51 and an upper part located in the steam layer S, and the second heat exchanger 54 has almost the third part. It is located in the steam layer S of the two heat exchange tank 52.

The low-temperature liquefied gas supplied from the low-temperature liquefied gas storage tank C or the like flows through the low-temperature liquefied gas introduction path 61 into the first heat exchanger 53 from below, and exchanges heat with firstly hot water and then with steam. As a result, it is vaporized and led out from the upper part of the first heat exchanger 53 to the low-temperature gas path 62. The gas in the low-temperature gas path 62 exits the first heat exchange tank 51 and travels to the second heat exchange tank 52, and the second heat exchanger 5 in the second heat exchange tank 52
4 flows from the lower part into the heat exchange with steam, is heated to a predetermined temperature, and is led out to the high-temperature gas path 63. The gas in the high-temperature gas path 63 enters the first heat exchange tank 51 again from the second heat exchange tank 52, and the third heat exchanger 5 in the first heat exchange tank 51.
5 flows from above. The gas flowing into the third heat exchanger 55 exchanges heat with steam, and then exchanges heat with hot water. Finally, the gas is heat-exchanged with hot water having a large heat capacity, so that the temperature of the gas is adjusted to a stable temperature. In a state, it is led from the third heat exchanger 55 to the gas supply path 64 and is supplied to the user's gas use facility.

As means for controlling the temperature of the supply gas, the first heat exchange tank 5 is connected to the gas supply path 64.
1 and a first temperature indicating controller (TI) that controls a first flow control valve 56V of a first steam introduction pipe 56 that supplies steam to the first steam introducing pipe 56.
C) 65 is provided, and a second temperature indicating controller 66 for controlling the second flow rate control valve 57V of the second steam introduction pipe 57 for supplying steam to the second heat exchange tank 52 is provided in the high temperature gas path 63. Is provided.

When the temperature of the supply gas falls below the set temperature, the first temperature indicating controller 65 operates the first flow rate control valve 56V in the opening direction to increase the steam supply amount, thereby increasing the steam supply amount in the first heat exchange tank 51. The temperatures of the steam layer S and the hot water layer W are increased. Similarly, when the temperature of the gas flowing through the high-temperature gas path 63 becomes lower than the set temperature, the second temperature indicating controller 66 operates the second flow rate control valve 57V in the opening direction to increase the steam supply amount and to increase the second heat control valve 57V. The temperature of the steam layer S in the exchange tank 52 is increased. Conversely, when the temperature of each gas rises, the temperature of each gas can be maintained at a predetermined temperature by reducing the amount of steam introduced.

As described above, after the low-temperature liquefied gas is vaporized by exchanging heat with the hot water having a large heat capacity in the first heat exchanger 53 whose lower portion is installed in the hot water layer W, the first heat exchanger 53 is installed in the steam layer S. Since the gas is heated by heat exchange with the high-temperature steam in the upper part of the heat exchanger 53 and the second heat exchanger 54, sufficient heating performance can be obtained with a small heat exchanger, and the entire evaporator can be heated. Small size can be achieved. Further, after the gas is heated in the second heat exchanger 54 to a temperature equal to or higher than the set temperature of the supply gas, finally, the hot water layer W
The heat is exchanged with hot water having a large heat capacity in the third heat exchanger 55 whose lower part is installed at a predetermined temperature to adjust the temperature of the supplied gas, so that the temperature of the supplied gas derived from the evaporator can be stabilized. .

Further, the temperature of the gas after heat exchange with steam is set higher than the set temperature of the supply gas in the second heat exchanger 54, and the temperature of the gas after heat exchange in the third heat exchanger 55 is set to the second temperature. By setting the temperature of the gas after the heat exchange in the heat exchanger 54 to be lower than that of the gas after the heat exchange, it is possible to effectively utilize the difference in heat capacity between the steam and the hot water and the temperature difference to perform efficient and stable temperature control.

In this embodiment, the steam to be supplied to the first heat exchange tank 51 is supplied from the first steam introduction pipe 56 to the steam layer S. It is also possible to extend and supply the hot water layer W by bubbling.

FIG. 3 is a system diagram showing a third embodiment of the evaporator of the present invention. This evaporator forms a small-sized evaporator having excellent temperature stability by utilizing the advantages of both a hot water evaporator and a steam evaporator, as in the second embodiment. In this embodiment, further miniaturization and simplification of the device configuration are achieved as compared with the second embodiment.

This evaporator comprises a steam layer S and a hot water layer W.
A first heat exchanger 72 housed in the hot water layer W, a second heat exchanger 73 housed in the steam layer S, and a hot water The third heat exchanger 74 housed in the layer W portion is installed, and the first heat exchanger 72, the second heat exchanger 73, and the third heat exchanger 74 are arranged in the gas flow direction. They are connected in series in the order of leverage.

In the heat exchange tank 71, a first steam introduction pipe 75 for supplying steam generated in the boiler B to the steam layer S, and a second steam introduction pipe 76 for supplying steam by bubbling steam into the warm water layer S are provided. The steam pipes 75 and 76 are provided with a first control valve 75V and a second control valve 76V as means for adjusting the steam supply amount. In addition, a drain 77 for returning drain water to the boiler B is provided at the bottom of the tank.

Further, a gas supply pipe 78 for supplying the gas vaporized by the evaporator to the gas using equipment is provided with a supply gas temperature indicating controller (which controls the opening and closing of the first control valve 75V by measuring the temperature of the supply gas). A hot water temperature indicating controller (TIC) 8 that measures the temperature of the hot water layer S and controls the opening and closing of the second control valve 76V is provided in the heat exchange tank 71.
2 are provided. Further, in the present embodiment, a flow indicator controller (FIC) 83 for measuring the flow rate of the supply gas is provided in the gas supply pipe 78, and the indication value of the flow indicator controller 83 and the indication value of the temperature indicator controller 81 are provided. Is processed by the computing unit 84, so that the opening and closing control of the first control valve 75V can be performed smoothly and accurately.

The low-temperature liquefied gas supplied from the low-temperature liquefied gas storage tank C or the like enters the heat exchange tank 71 through the low-temperature liquefied gas introduction path 85 and firstly the first heat exchanger installed in the hot water layer W 72. In this first heat exchanger 72,
Heat exchange is performed with the warm water in the warm water layer W to a predetermined temperature, and the low-temperature liquefied gas is vaporized. The gas vaporized in the first heat exchanger 72 is subsequently introduced into the second heat exchanger 73, where it performs heat exchange with the high-temperature steam of the steam layer S, and is heated to a temperature higher than the supply gas temperature. You. The high-temperature gas is introduced into the third heat exchanger 74, exchanges heat with the hot water in the hot water layer W, is cooled, and is adjusted to a predetermined supply gas temperature.

The gas whose temperature has been adjusted by the third heat exchanger 74 is led out of the heat exchange tank 71 to a gas supply pipe 78, and is supplied as a supply gas of a predetermined pressure and a predetermined temperature to a user gas use facility. . At this time, the first control valve 75V is controlled to open and close based on the measured values of the supply gas temperature indicating controller 81 and the flow rate indicating controller 83, so that the amount of steam to be supplied to the steam layer S is adjusted and the hot water temperature is indicated. The opening and closing of the second control valve 76V is controlled based on the measurement value of the controller 82, and the amount of steam supplied to the hot water layer W is adjusted. Thereby, the temperature of the supply gas supplied from the gas supply pipe 78 is controlled to a predetermined temperature.

In the evaporator shown in this embodiment,
After the low-temperature liquefied gas is vaporized by exchanging heat with hot water having a large heat capacity in the first heat exchanger 72 installed in the hot water layer W, heat exchange is performed with high-temperature steam in the second heat exchanger 73 installed in the steam layer S. Since the gas is heated in this way, sufficient heating performance can be obtained with the small second heat exchanger 73, and the entire evaporator can be reduced in size. Further, after the gas is heated to a temperature equal to or higher than the set temperature of the supply gas in the second heat exchanger 73, the heat is finally exchanged with hot water having a large heat capacity in the third heat exchanger 74 installed in the hot water layer W to supply the gas. Since the temperature is adjusted to the gas temperature, the temperature of the gas to be supplied after being vaporized by the evaporator can be stabilized.

Further, in this embodiment, one heat exchange tank 7
Since the first to third heat exchangers 72, 73, and 74 are housed in 1, the overall size and simplification of the evaporator of the second embodiment can be further reduced. Therefore, even if the entire evaporator, including the pump for raising the temperature of the low-temperature liquefied gas and the boiler for supplying steam, is integrated as one facility unit, it can be stored in a size that can be transported by truck or the like. It is easy to transport and install the gas, and can start gas supply quickly, making it ideal as an evaporator for spot use.

The temperature of the gas after heat exchange with steam is set higher than the set temperature of the supply gas in the second heat exchanger 73, and the temperature of the gas after heat exchange in the third heat exchanger 74 is set to the second temperature. By setting the temperature to be lower than the temperature of the gas after the heat exchange in the heat exchanger 73, the difference in heat capacity between the steam and the hot water and the temperature difference can be effectively used to efficiently and stably control the temperature.

The low-temperature liquefied gas supply source is the same not only in the low-temperature liquefied gas storage tank but also in the lorry, and the steam may be supplied from a boiler of a gas-using facility.
It may be supplied from a dedicated boiler attached to the evaporator.

[0044]

EXAMPLE 1 Using the evaporator of the first embodiment shown in FIG. 1, a liquid nitrogen of 0.3 MPa and -196.degree. C. mounted on a lorry was vaporized, and a nitrogen gas temperature-controlled to 60.degree. C. was supplied. An experiment was performed. The steam is supplied at 120 ° C. and 0.3 MPa, and by adjusting the supply amount of the steam and the shape of the heat exchanger, the main heat exchange tank 10 has a gas temperature of 80 ° C. after the heat exchange.
The temperature control heat exchange tank 20 was set so that the gas temperature after the heat exchange became 50 ° C.

When the temperature of the supply gas measured by the temperature indicating controller 31 exceeds 60 ° C., the flow rate control valve 27 is operated in the opening direction to increase the flow rate of the low temperature liquefied gas flowing through the temperature control heat exchange tank 20. Then, the mixing ratio of the low-temperature gas is increased to lower the temperature of the supply gas, and when the temperature of the supply gas falls below 60 ° C., the flow control valve 27 is operated in the closing direction to cause the low-temperature gas flowing through the heat exchange tank 20 for temperature control. The flow rate of the liquefied gas was reduced, the mixing ratio of the low-temperature gas was reduced, and the temperature of the supply gas was increased. As a result, a nitrogen gas having an average temperature of 60 ° C. and a temperature fluctuation range of ± 10 ° C. was supplied at a rate of about 5000 m ³ / h. Further, by performing the PID control, it was possible to perform temperature control with higher accuracy. Further, the experiment was conducted by changing the gas temperature after deriving both heat exchange tanks, but the evaporator of the present embodiment has a relatively high temperature, for example, 40 ° C.
It turned out to be suitable for gas supply at ６０60 ° C.

Example 2 Using the evaporator of the second embodiment shown in FIG. 2, the pressure of liquid nitrogen of 0.3 MPa and -193 ° C. in the low temperature liquefied gas storage tank was increased to 1 MPa by a pump, and the temperature was adjusted to 20 ° C. An experiment of supplying the supplied nitrogen gas was performed. Steam is 120 ℃, 0.3M
Pa was supplied. The volumes of the hot water layer W and the steam layer S in the first heat exchange tank 51 and the volume of the steam layer S in the second heat exchange tank 52 were each set to about 2 m ³ . The indicated temperature of the first temperature indicating controller 65 is 20 ° C., and the indicated temperature of the second temperature indicating controller 66 is 35 ° C., and when each gas temperature exceeds this temperature, the flow control valves 56V and 57V are opened. , And when each gas temperature fell, each flow control valve was operated in the closing direction.

By controlling in this manner, the temperature of the nitrogen gas vaporized in the first heat exchanger 53 is about 0 ° C., the temperature of the nitrogen gas heated in the second heat exchanger 54 is about 35 ° C., The temperature of the nitrogen gas cooled by the three heat exchangers 55 was about 20 ° C., and nitrogen gas having an average temperature of 20 ° C. and a temperature fluctuation range of ± 5 ° C. could be supplied at 5000 m ³ / h.

Example 3 Using the evaporator according to the second embodiment shown in FIG. 2, the pressure of liquid nitrogen of 0.3 MPa and -196 ° C. mounted on a lorry was increased to 1 MPa by a pump, and nitrogen adjusted to 20 ° C. An experiment of supplying gas was performed. Steam is 120 ℃, 0.3MP
a, and the temperature of the hot water was set at 15 ° C. The volume of the warm water layer W in the heat exchange tank 71 was about 2 m ³ , and the volume of the steam layer S was about 2.7 m ³ . The indicated temperature of the first temperature indicating controller 81 and the second temperature indicating controller 82 is set to 15 ° C., and when each gas temperature exceeds this temperature, each flow rate adjusting valve 75V,
76V was operated in the closing direction, and when each gas temperature fell, each flow control valve was operated in the opening direction.

By controlling in this manner, the temperature of the nitrogen gas vaporized in the first heat exchanger 72 is about 0 ° C., the temperature of the nitrogen gas heated in the second heat exchanger 73 is about 35 ° C., The temperature of the nitrogen gas cooled by the three heat exchangers 74 was about 20 ° C., and nitrogen gas having an average temperature of 20 ° C. and a temperature fluctuation range of ± 5 ° C. could be supplied at 5000 m ³ / h.

[0050]

As described above, according to the evaporator of the present invention, since steam is used as a heat medium,
The size of the entire evaporator can be reduced. Furthermore, by using steam and hot water together as a heat medium, the temperature of the supply gas can be further stabilized.

[Brief description of the drawings]

FIG. 1 is a system diagram showing a first embodiment of an evaporator according to the present invention.

FIG. 2 is a system diagram showing a second embodiment of the evaporator of the present invention.

FIG. 3 is a system diagram showing a third embodiment of the evaporator of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Main heat exchange tank, 11 ... Metal closed container, 12 ... Heat exchanger, 13 ... Steam introduction pipe, 14 ... Drain, 15 ... Low temperature liquefied gas introduction path, 16 ... Vaporized gas discharge path, 17 ...
Gas supply path, 20: heat exchange tank for temperature control, 21: metal hermetic container, 22: heat exchanger, 23: steam introduction pipe, 24
... Drain, 25 ... Low temperature liquefied gas introduction path for temperature control, 26 ...
Temperature control vaporized gas outlet path, 27: flow control valve, 31: temperature indicating controller, 51: first heat exchange tank, 52: second heat exchange tank, 53: first heat exchanger, 54: second heat exchange Container, 55 ...
Third heat exchanger, 56: first steam introduction pipe, 57: second steam introduction pipe, 58, 59 ... drain, 61 ... low temperature liquefied gas introduction path, 62 ... low temperature gas path, 63 ... high temperature gas path, 64 ... Gas supply path, 65: first temperature indicating controller,
66 ... second temperature indicating controller, 71 ... heat exchange tank, 72 ... first heat exchanger, 73 ... second heat exchanger, 74 ... third heat exchanger, 75 ... first steam introduction pipe, 76 ... Two steam introduction pipes, 77 drain, 78 gas supply pipe, 81 supply gas temperature indicating controller, 82 hot water temperature indicating controller, 83
Flow rate controller, 84: arithmetic unit, 85: low-temperature liquefied gas introduction path

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Atsushi Kobayashi 1-16-7 Nishi-Shimbashi, Minato-ku, Tokyo Nippon Sanso Corporation (72) Inventor Nobuyuki Takahashi 1-16-7, Nishi-Shimbashi, Minato-ku, Tokyo Japan Within Oxygen Co., Ltd. (72) Inventor Naora Ishikawa 1-1-15-1, Yamu, Tsurumi-ku, Yokohama, Kanagawa Prefecture Inside Acid Industry Co., Ltd. (72) Toshiyuki Takahashi 1-15-1, Yamu, Tsurumi-ku, Yokohama, Kanagawa 3L103 AA05 AA37 BB27 CC02 CC12 DD03 DD63

Claims (5)

[Claims] 1. An evaporator that heats and vaporizes a low-temperature liquefied gas by exchanging heat with a heat medium, wherein a heat exchanger into which the low-temperature liquefied gas is introduced is housed in a vessel into which the heat medium is introduced. A main heat exchange tank, a heat exchange tank for temperature control containing a heat exchanger in which a part of the low-temperature liquefied gas is introduced in a container into which the heat medium is introduced, and a low-temperature liquefaction in the heat exchanger of the main heat exchange tank. A low-temperature liquefied gas introduction path for introducing a gas, and a low-temperature liquefied gas introduction for branching from the low-temperature liquefied gas introduction path and introducing the low-temperature liquefied gas to the heat exchanger of the temperature-regulating heat exchange tank via a flow control valve Path, a vaporized gas derivation path for deriving gas vaporized in the heat exchanger of the main heat exchange tank, and a temperature control vaporized gas derivation path for deriving gas vaporized in the heat exchanger of the temperature control heat exchange tank, The gas of the vaporized gas outlet path and the vaporized gas for temperature control A gas supply path for merging and mixing the gas of the lead-out path and supplying the gas to the gas use destination, a temperature measuring means for measuring the temperature of the supply gas flowing through the gas supply path, and the temperature measuring means based on the measured temperature of the temperature measuring means. A control means for controlling the opening and closing of a flow control valve in a low-temperature liquefied gas introduction path for temperature control. 2. The evaporator according to claim 1, wherein the heat exchange capacity of the temperature control heat exchange tank is set to be different from the heat exchange capacity of the main heat exchange tank. 3. An evaporator that heats and vaporizes a low-temperature liquefied gas by exchanging heat with a heat medium, wherein the evaporator is provided in at least one heat exchange tank having a steam layer and a hot water layer as a heat medium. A first heat exchanger that is disposed in the hot water layer and into which the low-temperature liquefied gas is introduced, and a second heat exchanger that is disposed in the steam layer and into which heat-exchanged gas is introduced in the first heat exchanger. An evaporator comprising: a heat exchanger; and a third heat exchanger disposed in the hot water layer and into which the gas after heat exchange in the second heat exchanger is introduced. 4. The temperature of the gas after heat exchange in the second heat exchanger is set higher than the set temperature of the gas derived from the evaporator, and the gas after heat exchange in the third heat exchanger. The high-pressure gas supply equipment according to claim 3, wherein the temperature of the gas is set lower than the temperature of the gas after heat exchange in the second heat exchanger. 5. A temperature measuring means for measuring a temperature of a gas derived from the evaporator, a boiler for supplying steam into the heat exchange tank, and a thermometer for measuring the temperature of the gas based on the temperature of the gas measured by the temperature measuring means. The high-pressure gas supply equipment according to claim 3, further comprising steam supply amount adjusting means for adjusting the amount of steam supplied into the exchange tank.