JP7411601B2 - Intermediate heat exchanger - Google Patents

Description

The present invention relates to an intermediate medium heat exchanger.

Conventionally, as disclosed in Patent Document 1, as a device for vaporizing low-temperature liquefied gas such as liquefied natural gas (LNG), heat from a heat source medium is transferred to the intermediate medium while circulating an intermediate medium. Intermediate medium heat exchangers are known in which heat is transferred to low-temperature liquefied gas through the intermediate medium heat exchanger.

The intermediate medium type heat exchanger disclosed in Patent Document 1, as shown in FIG . 81 and an LNG vaporization section 82.

Specifically, the intermediate medium evaporator 81 includes a lower part 80b of the chamber 80 and a straight heat transfer tube 88 passed through the lower part 80b. The LNG vaporization section 82 includes an upper part 80t of the chamber 80 and a U-shaped heat transfer tube 93 passed through the upper part 80t. One chamber 80 is formed by the lower part 80b and the upper part 80t. An intermediate medium is enclosed within the chamber 80 . Seawater, which is a heat source medium, flows through the heat exchanger tubes 88 . LNG flows through the heat exchanger tubes 93. The intermediate medium accumulated in the chamber 80 is heated by seawater through the heat transfer tube 88 and becomes a gaseous intermediate medium GM. This gaseous intermediate medium GM is cooled by LNG via the heat transfer tube 93 and becomes a liquid intermediate medium LM. As a result, the intermediate medium circulates within the chamber 80 while changing its phase between gas and liquid.

Japanese Patent Application Publication No. 2017-120125

The intermediate medium type heat exchanger is composed of one chamber 80 which is a casing for an intermediate medium, a heat transfer tube 88 passed through an upper part 80t of the chamber 80, and a heat transfer tube 93 passed through a lower part 80b. For this reason, the intermediate medium heat exchanger cannot be manufactured using a general-purpose shell-and-tube heat exchanger, and must be specially designed and manufactured, which may increase costs. .

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an intermediate medium heat exchanger that can reduce costs.

As a means for solving the above problems, the present inventors have developed an LNG vaporization section (hereinafter referred to as "liquefied gas vaporizer") and an intermediate medium evaporation section (hereinafter referred to as "intermediate medium evaporator"). , two different shell-and-tube heat exchangers were used. The two shell-and-tube heat exchangers (liquefied gas vaporizer and intermediate medium evaporator) are connected to each other through a communication pipe. Specifically, it is as follows.

An intermediate medium heat exchanger according to one aspect of the present invention includes a first hollow chamber and a first heat transfer tube arranged to pass through the first chamber and into which a heat source medium flows. an intermediate medium evaporator having an intermediate medium evaporator, a hollow second chamber disposed above the first chamber, and a second chamber disposed so as to pass through the second chamber and into which low-temperature liquefied gas flows. a liquefied gas vaporizer having a heat exchanger tube; a multi-tube structure including an inner tube and an outer tube disposed radially outside the inner tube; and a communication pipe that communicates with each other. An intermediate medium is sealed in a space formed by the first chamber, the second chamber, and the communication pipe. The liquid intermediate medium in the first chamber is heated by the heat source medium through the first heat transfer tube and vaporized, becoming a gaseous intermediate medium, and the gaseous intermediate medium in the second chamber is vaporized. The intermediate medium is cooled and condensed into the low-temperature liquefied gas through the second heat transfer tube, and becomes a liquid intermediate medium. When one of the space inside the inner tube and the space between the inner tube and the outer tube is used as a first flow path and the other is used as a second flow path, the first flow path The channel includes a first upper opening that opens at a position above the liquid level of the liquid intermediate medium in the second chamber, and a first upper opening that opens at a position above the liquid level of the liquid intermediate medium in the first chamber. and a first lower opening that opens at an upper position, and functions as a gas flow path through which a gaseous intermediate medium flows. The second flow path has a second upper opening that opens at a position below the liquid level of the liquid intermediate medium in the second chamber, and a second lower opening that opens in the first chamber. and a side opening, and functions as a liquid flow path through which the liquid intermediate medium flows in a state where at least a portion thereof is filled with the liquid intermediate medium.

In an intermediate medium type heat exchanger, a liquid intermediate medium accumulated in a first chamber is heated by a heat source medium in the first chamber through a first heat transfer tube, and is vaporized, and is converted into a gaseous intermediate medium. become. The gaseous intermediate medium rises through a first channel serving as a gas channel in the communicating tube and flows into a second chamber of the liquefied gas vaporizer. Then, in the second chamber, the gaseous intermediate medium vaporizes the low-temperature liquefied gas by heating the low-temperature liquefied gas via the second heat transfer tube. At this time, the gaseous intermediate medium is cooled and condensed into low-temperature liquefied gas, and becomes a liquid intermediate medium again. The liquid intermediate medium accumulated in the second chamber flows into the first chamber through the second flow path that functions as a liquid flow path in the communication pipe. By repeating this series of operations, in the intermediate medium heat exchanger, heat is transferred from the heat source medium to the low-temperature liquefied gas through the circulation of the intermediate medium.

Further, in the intermediate medium heat exchanger, the intermediate medium evaporator has the first chamber, the liquefied gas vaporizer has the second chamber, and the inside of the first chamber and the Since the inside of the second chamber is communicated with each other through the communication pipe, it is not necessary to specially design and manufacture it, and it can be constructed using a general-purpose heat exchanger. Therefore, costs can be reduced.

Furthermore, in an intermediate medium heat exchanger, the liquid flow path and the gas flow path are constructed using communication tubes with a multi-tube structure. The number of communication pipes can be reduced compared to the case where the gas flow path and the gas flow path are configured.

In addition, in the intermediate medium type heat exchanger, the second flow path is at least partially filled with the liquid intermediate medium, so even if the gaseous intermediate medium flows into the second flow path, the second flow path is filled with the liquid intermediate medium. A state in which the liquid intermediate medium easily flows in the two channels is maintained, and the second channel can function as a liquid channel.

In a preferred embodiment of the intermediate medium heat exchanger, the intermediate medium heat exchanger is provided in the second flow path at a position above the liquid level of the liquid intermediate medium in the first chamber. , further comprising a liquid reservoir section for storing the liquid intermediate medium.

In the intermediate medium heat exchanger according to this aspect, since the liquid reservoir of the second flow path is filled with the liquid intermediate medium, the liquid intermediate medium is located at a position below the liquid level of the liquid intermediate medium in the first chamber. There is no need to extend the second flow path up to this point.

In a preferred embodiment of the intermediate medium type heat exchanger, the liquid reservoir section stores the liquid intermediate medium flowing out from the second lower opening of the second flow path, and the liquid intermediate medium that has accumulated therein. is configured to overflow from an upper edge located above the second lower opening.

In the intermediate medium heat exchanger according to this aspect, a certain amount of the liquid intermediate medium is maintained in the liquid reservoir, while the second lower opening is lower than the upper edge of the liquid reservoir. It is located at the bottom. Therefore, the gaseous intermediate medium in the first chamber cannot flow from the upper edge of the liquid reservoir toward the second lower opening. Therefore, the second flow path is in a state where it is liquid-sealed by the liquid reservoir.

Furthermore, in the intermediate medium type heat exchanger according to this aspect, the liquid reservoir can be easily provided in the communication tube of the multi-tube structure, and costs can be suppressed.

In a preferred embodiment of the intermediate medium heat exchanger, the second flow path includes an upper flow path portion extending downward from the second upper opening, and an upper end portion extending upward from the second lower opening. The liquid intermediate medium further includes a lower flow path portion located above a lower end portion of the upper flow path portion, and the liquid reservoir portion stores the liquid intermediate medium flowing out from the lower end portion of the upper flow path portion. On the other hand, the liquid intermediate medium that has accumulated is configured to flow into the upper end portion of the lower flow path portion.

In the intermediate medium heat exchanger according to this aspect, the liquid intermediate medium condensed in the second chamber flows into the liquid reservoir from the lower end of the upper flow passage of the second flow path, and from the liquid reservoir. It flows into the upper end of the lower flow path section and flows into the first chamber. At this time, in the liquid reservoir, a certain amount of the liquid intermediate medium is maintained between the upper end of the lower flow path and the lower end of the upper flow path. Since the lower end of the upper flow path is located below the upper end of the lower flow path, the gaseous intermediate medium vaporized in the first chamber rises up the lower flow path. Even if it did, the gaseous intermediate medium would not be able to reach the lower end of the upper channel section. Therefore, the upper flow path portion of the second flow path is in a liquid-sealed state by the liquid reservoir portion.

In a preferred embodiment of the intermediate medium heat exchanger, the liquid reservoir is formed in a shape including a curved surface that bends a downward flow of the liquid intermediate medium passing through the liquid reservoir into an upward flow. .

In the intermediate medium heat exchanger according to this aspect, since the liquid reservoir is formed in a shape including the curved surface, the liquid intermediate medium passing through the liquid reservoir changes direction so as to be curved. This reduces the flow resistance of the liquid intermediate medium passing through the liquid reservoir, and suppresses pressure loss due to the liquid reservoir.

In a preferred embodiment of the intermediate medium heat exchanger, the first flow path is formed as a space inside the inner pipe of the communication pipe, and the second flow path is formed as a space between the inner pipe and the outer pipe. The communication pipe is formed as a space, and the communication pipe is configured such that the liquid intermediate medium flowing out from the liquid reservoir section is carried by the flow of the gaseous intermediate medium that is about to enter the first lower opening. It further includes a liquid inflow prevention member that prevents liquid from flowing into the first flow path through the side opening.

In the intermediate medium heat exchanger according to this aspect, the second flow path is located outside the first flow path in the radial direction. Therefore, if the liquid inflow prevention member is not provided, the liquid intermediate medium that has flowed out from the liquid reservoir will ride on the flow of the gaseous intermediate medium that is about to enter the first lower opening. It attempts to flow into the first channel through the lower opening. For this reason, there is a possibility that the liquid intermediate medium becomes an obstacle to the flow of the gaseous intermediate medium in the first flow path functioning as a gas flow path. If the flow of the gaseous intermediate medium is obstructed, the amount of intermediate medium circulated throughout the intermediate heat exchanger will be reduced, resulting in a decrease in the efficiency of the intermediate heat exchanger. In contrast, in the intermediate medium heat exchanger according to this aspect, the liquid inflow prevention member prevents the liquid intermediate medium from flowing into the first flow path through the first lower opening. Therefore, in the intermediate medium heat exchanger according to this aspect, the liquid inflow suppressing member suppresses a decrease in the efficiency of the intermediate medium heat exchanger.

In a preferred embodiment of the intermediate medium heat exchanger, the liquid inflow prevention member extends downward from the liquid reservoir and has a lower end portion located below the first lower opening of the first flow path. have

In the intermediate medium heat exchanger according to this aspect, the lower end of the liquid inflow prevention member extending downward from the liquid reservoir is located below the first lower opening of the first flow path. Therefore, the liquid intermediate medium flowing out from the liquid reservoir flows into the first channel through the first lower opening, riding on the flow of the gaseous intermediate medium that is about to enter the first lower opening. This will be more effectively suppressed.

In a preferred embodiment of the intermediate medium heat exchanger, the liquid inflow suppressing member is inclined with respect to the vertical direction so as to be radially away from the first lower opening of the first flow path.

In the intermediate medium heat exchanger according to this aspect, the distance between the lower end of the liquid inflow prevention member and the first lower opening is increased, and the liquid intermediate medium flowing out from the liquid reservoir is transferred to the first lower opening. Flow into the first flow path through the side opening is more effectively suppressed.

In a preferred embodiment of the intermediate medium heat exchanger, the liquid inflow prevention member is arranged continuously in the circumferential direction of the first flow path or so as to surround the first lower opening of the first flow path. It is formed discontinuously.

In the intermediate medium type heat exchanger according to this aspect, the liquid inflow prevention member surrounds the first lower opening in the circumferential direction of the first flow path, so that the liquid flows out from any position in the circumferential direction of the liquid reservoir. The liquid intermediate medium is prevented from flowing into the first flow path through the first lower opening. In addition, in this aspect, when the liquid inflow suppressing member is discontinuously formed, there is a state in which the liquid inflow suppressing member suppresses the inflow of the liquid intermediate medium but does not suppress the inflow of the gaseous intermediate medium. It becomes possible.

In a preferred embodiment of the intermediate medium heat exchanger, the second lower opening of the second flow path is located at a position below the liquid level of the liquid intermediate medium in the first chamber. As a result, it is immersed in the liquid intermediate medium.

In the intermediate medium heat exchanger according to this aspect, the second lower opening, which is the lower end of the second flow path that functions as a liquid flow path, is immersed in the liquid intermediate medium accumulated in the first chamber. Therefore, the second flow path can be operated with the entire second flow path filled with the liquid intermediate medium. Therefore, even if the gaseous intermediate medium flows into the second flow path, a state in which the liquid intermediate medium easily flows is maintained in the second flow path, and the second flow path functions as a liquid flow path. can continue to do so.

In a preferred embodiment of the intermediate medium heat exchanger, the second lower opening of the second flow path is located at a position laterally shifted from directly above the first heat exchanger tube in the first chamber. It is located in

When the second lower opening of the second flow path, which is immersed in the liquid intermediate medium in the first chamber, is located directly above the first heat transfer tube, the second There is a possibility that the gaseous intermediate medium generated from the first heat transfer tube may flow into the flow path. However, in the intermediate medium heat exchanger according to this aspect, the second lower opening is disposed in the first chamber at a position shifted laterally from directly above the first heat exchanger tube. Gaseous intermediate medium is suppressed from flowing into the second flow path from the lower opening.

In a preferred embodiment of the intermediate medium heat exchanger, the intermediate medium evaporator is configured such that the gaseous intermediate medium in the first chamber flows into the second flow path through the second lower opening. It further includes a gas inflow suppressing member for suppressing this.

In the intermediate medium heat exchanger according to this aspect, even if the gaseous intermediate medium generated in the first chamber of the intermediate medium evaporator floats in the liquid, the second flow is caused to flow from the second lower opening. This prevents water from flowing into the road.

In a preferred embodiment of the intermediate medium heat exchanger, the hydraulic diameter of the first flow path is larger than the hydraulic diameter of the second flow path.

In the intermediate medium heat exchanger according to this aspect, pressure loss due to the first channel through which the gaseous intermediate medium flows is suppressed.

In a preferred embodiment of the intermediate medium heat exchanger, the first upper opening and the first lower opening of the first flow path are formed in a reverse tapered shape to increase the opening diameter.

In the intermediate medium heat exchanger according to this aspect, pressure loss due to the first channel through which the gaseous intermediate medium flows is suppressed.

In a preferred embodiment of the intermediate medium heat exchanger, the second upper opening of the second flow path is formed in a reverse tapered shape to increase the opening diameter.

In the intermediate medium heat exchanger according to this aspect, pressure loss due to the second channel through which the liquid intermediate medium flows is suppressed.

In a preferred embodiment of the intermediate medium heat exchanger, the intermediate medium heat exchanger further includes a second communication pipe. The second communication pipe has a multi-tube structure including an inner pipe and an outer pipe disposed radially outside the inner pipe, and communicates the inside of the first chamber and the inside of the second chamber with each other. However, one of the space inside the inner tube and the space between the inner tube and the outer tube is used as the first flow path, and the other is used as the second flow path.

Since the intermediate medium heat exchanger according to this aspect includes a plurality of communication pipes, it is possible to increase the amount of intermediate medium circulated between the intermediate medium evaporator and the liquefied gas vaporizer, and the intermediate medium The efficiency of the heat exchanger can be improved.

In a preferred embodiment of the intermediate medium heat exchanger, at least one of the inner tube and the outer tube is provided with a heat insulating material.

In the intermediate medium type heat exchanger according to this aspect, when the inner pipe is provided with a heat insulating material, the effect of heat exchange between the inner pipe and the outer pipe is suppressed, and the outer pipe is provided with a heat insulating material. In this case, the influence of heat exchange between the intermediate medium flowing through the outer tube and the atmosphere can be suppressed.

The intermediate medium heat exchanger according to the present invention can reduce costs.

1 is a front sectional view showing an intermediate medium heat exchanger according to a first embodiment of the present invention. 1 is a side cross-sectional view showing an intermediate medium heat exchanger according to a first embodiment of the present invention, and is a cross-sectional view taken along the line II-II in FIG. 1. FIG. It is a side sectional view of the intermediate medium heat exchanger which shows the 1st modification of 1st Embodiment of this invention. It is a side sectional view of the intermediate medium heat exchanger which shows the 2nd modification of 1st Embodiment of this invention. It is a side sectional view of the intermediate medium heat exchanger which shows the 3rd modification of 1st Embodiment of this invention. It is a side sectional view of the intermediate medium heat exchanger which shows the 4th modification of 1st Embodiment of this invention. It is a side sectional view of the intermediate medium heat exchanger which shows the 5th modification of 1st Embodiment of this invention. It is a side sectional view of the intermediate medium heat exchanger which shows the 6th modification of 1st Embodiment of this invention. It is a front sectional view of an intermediate medium type heat exchanger showing a seventh modification of the first embodiment of the present invention. It is a front sectional view of the intermediate medium type heat exchanger which shows the 8th modification of 1st Embodiment of this invention. 11 is an enlarged view of region XI in FIG. 10. FIG. FIG. 3 is a side sectional view showing an intermediate medium heat exchanger according to a second embodiment of the present invention. It is a side sectional view of the intermediate medium heat exchanger which shows the 1st modification of 2nd Embodiment of this invention. It is a side sectional view of the intermediate medium heat exchanger which shows the 2nd modification of 2nd Embodiment of this invention. It is a side sectional view of the intermediate medium heat exchanger which shows the 3rd modification of 2nd Embodiment of this invention. It is a side sectional view of the intermediate medium heat exchanger which shows the 4th modification of 2nd Embodiment of this invention. It is a side sectional view of the intermediate medium heat exchanger which shows the 5th modification of 2nd Embodiment of this invention. It is a side sectional view of the intermediate medium heat exchanger which shows the 6th modification of 2nd Embodiment of this invention. FIG. 2 is a front sectional view showing a conventional intermediate medium heat exchanger.

Hereinafter, an intermediate medium heat exchanger according to an embodiment will be described. In addition, in the following description, the communication pipe will be described on the assumption that it has a radially symmetrical shape, except for the first modification and the third modification of the second embodiment shown in FIGS. 13 and 15 . Is going.

(First embodiment)
An intermediate medium heat exchanger is a heat exchanger that exchanges heat between a heat source medium and low-temperature liquefied gas via an intermediate medium. An intermediate medium heat exchanger circulates an intermediate medium, transfers heat from a heat source medium to liquefied natural gas (LNG) via the intermediate medium, and vaporizes the LNG to generate natural gas (NG). Note that the intermediate medium heat exchanger is not limited to a configuration that vaporizes LNG as a low-temperature liquefied gas, but may also vaporize, for example, ethylene, liquefied oxygen, liquefied nitrogen, or the like. Further, the heat source medium is seawater, industrial water, or the like.

As shown in FIGS. 1 and 2, the intermediate medium heat exchanger 1 includes an intermediate medium evaporator E1, a liquefied gas vaporizer E2, a communication pipe 30, and a liquid reservoir 40. The intermediate medium heat exchanger 1 has a closed space formed by an intermediate medium evaporator E1, a liquefied gas vaporizer E2, and a communication pipe 30. In the space of the intermediate medium heat exchanger 1, intermediate media LM and GM are sealed.

The intermediate medium evaporator E1 is constituted by a shell and tube type heat exchanger. That is, the intermediate medium evaporator E1 includes a hollow chamber (first chamber) 10c whose longitudinal direction is horizontal, and a first heat exchanger tube 10d arranged to pass through the first chamber 10c. , has. In the intermediate medium evaporator E1, heat exchange is performed between the heat source medium in the first heat transfer tube 10d and the liquid intermediate medium LM in the first chamber 10c, and the liquid intermediate medium is heated by the heat from the heat source medium. LM evaporates and a gaseous intermediate medium GM is produced.

As shown in FIG. 1, the first heat exchanger tube 10d has a straight tube shape and is arranged so as to pass through the lower side (bottom side) of the first chamber 10c. The first heat exchanger tube 10d passes through the first chamber 10c in its longitudinal direction. In the first heat exchanger tube 10d, the heat source medium flows in from the left side in FIG. 1 and flows out to the right side in FIG. 1 (that is, from one side in the longitudinal direction of the heat exchanger tube 10d to the other side). As shown in FIG. 2, a plurality of first heat exchanger tubes 10d are prepared.

In the first chamber 10c, when the intermediate medium heat exchanger 1 is in operation, as shown in FIGS. 1 and 2, a liquid intermediate medium LM is accumulated. The first heat transfer tube 10d is immersed in the liquid intermediate medium LM accumulated in the first chamber 10c.

The liquefied gas vaporizer E2 is constituted by a shell and tube type heat exchanger. That is, the liquefied gas vaporizer E2 includes a hollow chamber (second chamber) 20c that is arranged above the first chamber 10c and whose longitudinal direction is horizontal, and a chamber that passes through the second chamber 20c. and a second heat exchanger tube 20d disposed in the second heat exchanger tube 20d. In the liquefied gas vaporizer E2, heat exchange is performed between the gaseous intermediate medium GM in the second chamber 20c and the low-temperature liquefied gas in the second heat transfer tube 20d, and the heat of the intermediate medium GM causes low-temperature liquefaction. The gas evaporates. At this time, the gaseous intermediate medium GM is cooled to a low-temperature liquefied gas, thereby generating the liquid intermediate medium LM.

As shown in FIG. 1, the second heat transfer tube 20d has a U-shape and is arranged to pass through the second chamber 20c with a space between it and the bottom of the second chamber 20c. has been done. Specifically, one end of the second heat exchanger tube 20d is connected to one side wall in the longitudinal direction of the second chamber 20c, and extends to the vicinity of the other side wall in the longitudinal direction of the second chamber 20c. The second heat exchanger tube 20d is bent back near the other side wall in the longitudinal direction, and the other end is connected to the one side wall in the longitudinal direction of the second chamber 20c. As shown in FIG. 2, a plurality of second heat exchanger tubes 20d are prepared. Note that the second heat exchanger tube 20d is not limited to having a U-shape, but may be a straight tube. In this specification, "one side in the longitudinal direction" shall mean the left side in FIG. 1, and "the other side in the longitudinal direction" shall mean the right side in FIG. 1.

In the second chamber 20c, in the operating state of the intermediate medium type heat exchanger 1, as shown in FIGS. 1 and 2, a gaseous intermediate medium GM and a liquid intermediate medium LM are accumulated. The second heat transfer tube 20d is arranged above and apart from the liquid intermediate medium LM accumulated in the second chamber 20c.

As shown in FIG. 2, the communication tube 30 is a tube with a double tube structure including an inner tube 31 and an outer tube 32 disposed radially outside the inner tube 31. The communication tube 30 communicates the inside of the first chamber 10c and the inside of the second chamber 20c with each other through an inner tube 31 and an outer tube 32, respectively.

The upper end of the outer tube 32 is connected to a bottom portion forming the lower surface of the second chamber 20c, for example, by welding. The upper end of the outer tube 32 is open into the liquid intermediate medium LM accumulated in the second chamber 20c. An intermediate portion of the outer tube 32 is connected to a top surface forming the upper surface of the first chamber 10c, for example, by welding. The outer tube 32 passes through the top surface of the first chamber 10c. That is, the lower end of the outer tube 32 enters into the first chamber 10c. The lower end of the outer tube 32 is opened in the first chamber 10c at a position above the liquid level of the liquid intermediate medium LM accumulated in the first chamber 10c.

The inner tube 31 is arranged inside the outer tube 32 so as to extend from the space within the first chamber 10c to the space within the second chamber 20c. The length of the inner tube 31 is set to be longer than the length of the outer tube 32. The upper end of the inner tube 31 is set higher than the upper end of the outer tube 32 and higher than the liquid level of the liquid intermediate medium LM accumulated in the second chamber 20c. The upper end of the inner tube 31 opens into the gaseous intermediate medium GM in the second chamber 20c. The lower end of the inner tube 31 is set to be lower than the lower end of the outer tube 32 and higher than the liquid level of the liquid intermediate medium LM accumulated in the first chamber 10c. The lower end of the inner tube 31 opens into the gaseous intermediate medium GM in the first chamber 10c.

The communication tube 30 forms a space inside the inner tube 31 and between the inner tube 31 and the outer tube 32, respectively. In the first embodiment, the space inside the inner tube 31 is defined as a first flow path F1, and the space between the inner tube 31 and the outer tube 32 is defined as a second flow path F2.

The first flow path F1 includes a first upper opening F1b, which is an opening formed by the upper end of the inner tube 31, and a first lower opening F1a, which is an opening formed by the lower end of the inner tube 31. has. The first upper opening F1b is located above the liquid intermediate medium LM that accumulates in the second chamber 20c. The first lower opening F1a is located at a lower position than a second lower opening F2a, which will be described later, and is located at a height of the second lower opening F2a and the liquid accumulated in the first chamber 10c. It is located at a position between the liquid level of the intermediate medium LM.

The second flow path F2 includes an annular second upper opening F2b that is an opening formed by the upper end of the outer tube 32 and the inner tube 31, and an opening formed by the lower end of the outer tube 32 and the inner tube 31. It has an annular second lower opening F2a which is a section. The second upper opening F2b opens into the liquid intermediate medium LM accumulated in the second chamber 20c at a position below the first upper opening F1b. The second lower opening F2a opens at a position between the height position where the outer tube 32 connects to the first chamber 10c and the liquid level of the liquid intermediate medium LM accumulated in the first chamber 10c. There is.

The liquid intermediate medium LM in the second chamber 20c flows into the second flow path F2 through the second upper opening F2b, and the liquid intermediate medium LM in the second flow path F2 flows into the second flow path F2 through the second lower opening F2b. It flows into the first chamber 10c through the portion F2a. That is, the second flow path F2 functions as a liquid flow path through which the liquid intermediate medium LM flows.

On the other hand, the gaseous intermediate medium GM in the first chamber 10c flows into the first flow path F1 through the first lower opening F1a, and the gaseous intermediate medium GM in the first flow path F1 is It flows into the second chamber 20c through the first upper opening F1b. That is, the first flow path F1 functions as a gas flow path through which the gaseous intermediate medium GM flows.

The liquid reservoir section 40 is a section that stores the liquid intermediate medium LM, and is located inside the first chamber 10c on the radially outer side of the first flow path F1 (inner pipe 31) and the second flow path F2 in the communication pipe 30. It is provided below the second lower opening F2a (below the lower end of the outer tube 32) and above the liquid level of the liquid intermediate medium LM in the first chamber 10c.

The liquid reservoir 40 is formed in a downwardly convex shape. The liquid reservoir 40 extends radially from the outer surface of the tube wall of the inner tube 31 to a position radially outer than the tube wall of the outer tube 32 below the second lower opening F2a of the second flow path F2. It has a bottom part extending in the direction, and a vertical wall part extending upward from the outer edge of the bottom part to a position above the second lower opening F2a in the height direction. The upper edge of the vertical wall forms the upper edge 42 of the liquid reservoir 40. In other words, the liquid reservoir 40 stores the liquid intermediate medium LM flowing out from the second lower opening F2a of the second flow path F2 from the bottom surface to the height of the upper edge 42, and at the same time, the liquid intermediate medium LM that has accumulated The medium LM is configured to overflow from the upper edge 42 of the liquid reservoir 40 located above the second lower opening F2a.

The second lower opening F2a is immersed in the liquid intermediate medium LM stored in the liquid reservoir 40. As a result, the second flow path F2 is filled with the liquid intermediate medium LM.

Next, the operational effects of the intermediate medium heat exchanger 1 according to the first embodiment will be explained.

In the intermediate medium type heat exchanger 1, the liquid intermediate medium LM accumulated in the first chamber 10c is heated and vaporized by the heat source medium through the first heat transfer tube 10d, and becomes a gaseous intermediate medium GM. Become. The gaseous intermediate medium GM once accumulates in the upper side of the first chamber 10c, and then rises through the space inside the inner tube 31 of the communication tube 30 (the first flow path F1) and flows into the liquefied gas vaporizer E2. It flows into the second chamber 20c. In the second chamber 20c, the gaseous intermediate medium GM vaporizes the low-temperature liquefied gas by heating the low-temperature liquefied gas via the second heat transfer tube 20d. At this time, the gaseous intermediate medium GM is cooled and condensed into low-temperature liquefied gas, and becomes the liquid intermediate medium LM again. The liquid intermediate medium LM once accumulated in the second chamber 20c is transferred to the first chamber 10c through the space (second passage F2) between the inner tube 31 and the outer tube 32 of the communication tube 30. The liquid flows into the liquid reservoir 40 inside. The liquid reservoir 40 causes the liquid intermediate medium LM to overflow from the upper edge 42 of the liquid reservoir 40 while maintaining a state in which a certain amount of the liquid intermediate medium LM is accumulated. The overflowing liquid intermediate medium LM accumulates in the first chamber 10c again. By repeating this series of operations, in the intermediate medium heat exchanger 1, heat is transferred from the heat source medium to the low-temperature liquefied gas through the circulation of the intermediate medium.

As explained above, in the intermediate medium heat exchanger 1 according to the first embodiment, the intermediate medium evaporator E1 has the first chamber 10c, and the liquefied gas vaporizer E2 has the second chamber 20c. The inside of the first chamber 10c and the inside of the second chamber 20c are communicated with each other through a communication pipe 30. Therefore, the intermediate medium type heat exchanger 1 does not need to be specially designed, and can be constituted by a general-purpose heat exchanger. Therefore, costs can be reduced.

Furthermore, in the intermediate medium heat exchanger 1 according to the first embodiment, since the liquid flow path and the gas flow path are configured by the communication pipe 30 having a double pipe structure, a plurality of units provided at mutually different positions are used. The number of communication pipes can be reduced compared to the case where the liquid flow path and the gas flow path are each configured with communication pipes having a tubular structure. Moreover, as a result, when the communication pipe 30 is connected to the first chamber 10c and the second chamber 20c by welding, the gaseous intermediate medium GM may leak from each connection point of the communication pipe 30. It is possible to reduce the

Furthermore, in the intermediate medium type heat exchanger 1 according to the first embodiment, the liquid intermediate medium LM is stored in the liquid reservoir 40 so that the second flow path F2 is filled with the liquid intermediate medium LM. A state in which the liquid intermediate medium LM easily flows in the flow path F2 is maintained.

Further, in the intermediate medium heat exchanger 1 according to the first embodiment, since the liquid reservoir 40 of the second flow path F2 is filled with the liquid intermediate medium LM, the liquid intermediate medium LM in the first chamber 10c There is no need to extend the second flow path F2 to a position below the liquid level.

In the intermediate medium heat exchanger 1 according to the first embodiment, a certain amount of liquid intermediate medium LM is maintained in the liquid reservoir 40, while the second lower opening F2a is filled with liquid. It is located below the upper edge 42 of the reservoir 40. Therefore, the gaseous intermediate medium GM in the first chamber 10c cannot move from the upper edge 42 of the liquid reservoir 40 to the second lower opening F2a. Therefore, the second flow path F2 is in a liquid-sealed state by the liquid reservoir 40.

Furthermore, in the intermediate medium heat exchanger 1 according to the first embodiment, the liquid reservoir 40 can be easily provided in the communication tube 30 having a multi-tube structure, and costs can be suppressed.

Note that the liquid reservoir 40, the first lower opening F1a and the first upper opening F1b of the first flow path F1, and the second upper opening F2b of the second flow path F2 are in the form of FIGS. 1 and 2. Not limited. For example, as in the first modification shown in FIG. 3, the liquid reservoir 40 is formed in a shape including a curved surface that bends the downward flow of the liquid intermediate medium LM passing through the liquid reservoir 40 into an upward flow. may have been done. More specifically, the bottom surface of the liquid reservoir 40 may be curved so as to protrude downward below the second lower opening F2a of the second flow path F2.

Further, the first lower opening F1a and the first upper opening F1b of the first flow path F1 may each be formed in a tapered shape (reverse tapered shape) so as to increase the opening diameter.

Furthermore, the second upper opening F2b of the second flow path F2 may be formed in a tapered shape (reverse tapered shape) so as to increase the opening diameter.

In the intermediate medium heat exchanger 1 according to the first modification, the liquid reservoir 40 is formed in a shape including a curved surface, so that the liquid intermediate medium LM passing through the liquid reservoir 40 is curved. Change direction. Thereby, the flow resistance of the liquid intermediate medium LM passing through the liquid reservoir 40 is reduced, and pressure loss due to the liquid reservoir 40 is suppressed.

Furthermore, since the first lower opening F1a and the first upper opening F1b of the first flow path F1 are formed in the reverse tapered shape as described above, the first flow path through which the gaseous intermediate medium GM flows Pressure loss due to F1 is suppressed.

Similarly, since the second upper opening F2b of the second flow path F2 is formed in the reverse tapered shape as described above, pressure loss due to the second flow path F2 through which the liquid intermediate medium LM flows can be suppressed.

If the pressure loss in the flow of the intermediate media LM and GM is suppressed in at least a portion of the first flow path F1, the second flow path F2, and the liquid reservoir 40, it is possible to suppress the length of the communication pipe 30. becomes. That is, in the liquid intermediate medium LM passing through the second flow path F2, the liquid level changes from the upper liquid level (the liquid level of the liquid intermediate medium LM accumulated in the second chamber 20c) to the lower liquid level (the liquid level of the liquid intermediate medium LM accumulated in the second chamber 20c). The difference in liquid level height from the liquid level of the liquid intermediate medium LM accumulated in balance the difference between the internal pressure and the internal pressure. Therefore, when the pressure loss is suppressed, the difference in liquid level height becomes smaller, and it becomes possible to suppress the length required for the communication pipe 30.

On the other hand, the communication pipe 30 may include, for example, a liquid inflow prevention member 34 shown in FIGS. 4 and 5. The liquid inflow suppressing member 34 is for suppressing the liquid intermediate medium LM from flowing into the first flow path F1, and is configured to extend downward from the liquid reservoir 40.

More specifically, the liquid inflow suppressing member 34 is formed in an annular shape surrounding the lower end of the inner tube 31, that is, the first lower opening F1a of the first flow path F1, and extends from the bottom of the liquid reservoir 40. It is formed to hang down. The lower end portion 35 of the liquid inflow suppressing member 34 is located below the first lower opening F1a of the first flow path F1.

The liquid inflow suppressing member 34 is preferably formed continuously in the circumferential direction of the first flow path F1, but may be formed discontinuously. Further, as in the third modification shown in FIG. 5, the liquid inflow suppressing member 34 is inclined with respect to the vertical direction so as to radially move away from the first lower opening F1a as it goes downward. Good too.

In the intermediate medium heat exchanger 1 according to the second modified example shown in FIG. 4 and the third modified example shown in FIG. 1 flow into the flow path F1 is suppressed. That is, when a droplet flows into the first flow path F1, it may adhere to the inner surface of the first flow path F1, but this is suppressed by the liquid inflow suppressing member 34. Therefore, in the intermediate medium heat exchanger 1 according to the second modification and the third modification, the liquid inflow suppressing member 34 suppresses a decrease in the efficiency of the intermediate medium heat exchanger 1.

Further, in the intermediate medium heat exchanger 1 according to the second modification example shown in FIG. 4 and the third modification example shown in FIG. It is located below the opening F1a. Therefore, the liquid intermediate medium LM flowing out from the liquid reservoir 40 rides on the flow of the gaseous intermediate medium GM that is about to enter the first lower opening F1a and enters the first flow through the first lower opening F1a. Inflow into the path F1 is more effectively suppressed.

Furthermore, in the intermediate medium heat exchanger 1 according to the second modification shown in FIG. 4 and the third modification shown in FIG. By surrounding in the circumferential direction, the liquid intermediate medium LM flowing out from any position in the circumferential direction of the liquid reservoir 40 is prevented from flowing into the first flow path F1 through the first lower opening F1a.

Furthermore, in the intermediate medium type heat exchanger 1 according to the third modification example of FIG. F1a increases, and the liquid intermediate medium LM flowing out from the liquid reservoir 40 is more effectively prevented from flowing into the first flow path F1 through the first lower opening F1a.

The liquid reservoir 40 may be provided in the middle of the communication pipe 30, for example, as in a fourth modification shown in FIG. That is, while the liquid reservoir 40 shown in FIG. 2 was arranged below the lower end of the outer tube 32 in the first chamber 10c, in the fourth modification shown in FIG. It is arranged between the first chamber 10c and the second chamber 20c, and also in the space formed between the inner tube 31 and the outer tube 32.

In the fourth modification, the outer tube 32 of the communication tube 30 includes an upper outer tube section 32K connected to the second chamber 20c, a lower outer tube section 32M connected to the first chamber 10c, and an outer tube lower section 32M connected to the first chamber 10c. It has an outer tube enlarged diameter section 32L provided so as to connect the upper section 32K and the outer tube lower section 32M.

The diameter of the outer tube enlarged diameter portion 32L is larger than the diameters of the outer tube upper portion 32K and the outer tube lower portion 32M. That is, the outer tube enlarged diameter portion 32L has a top surface portion that extends radially outward from the outer surface of the outer tube upper portion 32K, and a top surface portion that extends downward from the outer peripheral edge of the top surface portion and is curved or bent radially inward at the extended end. and an outer wall portion connected to the upper end of the outer tube lower portion 32M. The outer tube enlarged diameter portion 32L covers the liquid reservoir portion 40.

The liquid reservoir portion 40 is provided within a space formed by the outer tube enlarged diameter portion 32L and the inner tube 31. The bottom surface of the liquid reservoir 40 passes from the outer surface of the inner tube 31 through the gap between the lower end of the outer tube upper section 32K and the upper end of the outer tube lower section 32M to the outer tube upper section 32K and the outer tube lower section. It extends radially outward from 32M. That is, unlike the first embodiment, the bottom portion is disposed below the lower end of the outer tube upper portion 32K and above the upper end of the outer tube lower portion 32M. The vertical wall portion of the liquid reservoir portion 40 extends outside the outer tube upper portion 32K from the outer peripheral end of the bottom portion to above the lower end of the outer tube upper portion 32K. The upper edge portion 42 of the vertical wall portion forms a gap with the top surface portion of the outer tube enlarged diameter portion 32L. The vertical wall portion forms a gap in the radial direction between the vertical wall portion and the outer wall portion of the outer tube enlarged diameter portion 32L. Furthermore, the vertical wall portion forms a gap in the radial direction between the vertical wall portion and the outer tube upper portion 32K.

The second flow path F2 includes an upper flow path portion F21 extending downward from the second upper opening F2b, and a lower flow path portion F22 extending upward from the second lower opening F2a.

The upper flow path portion F21 is a space formed between the outer tube upper portion 32K and the inner tube 31. The lower end portion F21s of the upper flow path portion F21 is formed by the lower end of the outer tube upper portion 32K and the inner tube 31.

The lower flow path portion F22 includes a portion formed by the upper edge portion 42 of the vertical wall portion of the liquid reservoir portion 40 and the top surface portion of the outer tube enlarged diameter portion 32L, and a portion formed by the liquid reservoir portion 40 and the outer tube enlarged diameter portion 32L. and a portion formed by the inner tube 31 and the lower outer tube portion 32M. The upper end portion F22t of the lower flow path portion F22 is formed as a space between the upper edge portion 42 of the liquid reservoir portion 40 and the top surface portion of the outer tube enlarged diameter portion 32L.

In this case, the liquid inflow suppressing member 34 may be provided so as to extend from the inner tube 31. The liquid inflow suppressing member 34 is located below the second lower opening F2a of the second flow path F2 and extends radially outward from the outer surface of the inner tube 31 that forms the first flow path F1 inside. It extends downwardly. That is, the liquid inflow suppressing member 34 is inclined with respect to the vertical direction so as to be radially away from the first lower opening F1a of the first flow path F1. Also in this case, the lower end portion 35 of the liquid inflow suppressing member 34 is located below the first lower opening F1a.

In the intermediate medium heat exchanger 1 according to the fourth modification, the liquid reservoir 40 forms a downwardly convex space, and the liquid flowing through the upper flow path F21 of the second flow path F2 is stored in this space. intermediate medium LM is stored. The liquid intermediate medium LM overflowing from the upper edge portion 42 of the liquid reservoir portion 40 is guided by the top surface portion and outer wall portion of the outer tube enlarged diameter portion 32L, flows into the lower flow path portion F22, and flows into the first chamber. Head to 10c. That is, the liquid reservoir section 40 stores the liquid intermediate medium LM flowing out from the lower end F21s of the upper flow path section F21, and also transfers the accumulated liquid intermediate medium LM to the upper end F22t of the lower flow path section F22. It is configured to allow inflow.

In the intermediate medium heat exchanger 1 according to the fourth modification, in the liquid reservoir 40, the liquid is A state in which a certain amount of intermediate medium LM is accumulated is maintained. Since the lower end portion F21s of the upper flow path portion F21 is located below the upper end portion F22t of the lower flow path portion F22, the gaseous intermediate medium GM vaporized within the first chamber 10c is Even if the flow path portion F22 is raised, the gaseous intermediate medium GM cannot move toward the lower end portion F21s of the upper flow path portion F21. Therefore, the upper flow path portion F21 of the second flow path F2 is in a liquid-sealed state by the liquid reservoir portion 40.

Furthermore, in the intermediate medium type heat exchanger 1 according to the fourth modification, the upper flow path portion F21, which is a part of the second flow path F2, is liquid-sealed in the liquid reservoir portion 40 and is filled with the liquid intermediate medium LM. Since the second flow path F2 is filled, a state in which the liquid intermediate medium LM easily flows is maintained in the second flow path F2, and the second flow path F2 can function as a liquid flow path.

Further, in the intermediate medium heat exchanger 1 according to the fourth modification, the liquid intermediate medium LM flows out from the liquid reservoir 40 provided in the middle of the second flow path F2 of the communication pipe 30. 2 drips from the lower opening F2a. At this time, the liquid inflow suppressing member 34 causes the liquid intermediate medium LM in the form of droplets to flow toward the first lower opening F1a located lower and radially inward than the second lower opening F2a. The intermediate medium GM is prevented from flowing into the first flow path F1 from the first lower opening F1a along with the flow of the intermediate medium GM.

For example, as in the fifth modification shown in FIG. 7, the communication pipe 30 allows the space inside the inner pipe 31 to function as a second flow path F2, which is a liquid flow path, contrary to the first embodiment. , the space between the inner tube 31 and the outer tube 32 may function as the first flow path F1, which is a gas flow path. In this case, the liquid reservoir 40 may be provided below the second lower opening F2a formed by the lower end of the inner tube 31 of the communication tube 30.

The communication pipe 30 includes an inner pipe 31 and an outer pipe 32 arranged radially outside the inner pipe 31. The upper end of the outer tube 32 enters into the second chamber 20c, and the lower end enters into the first chamber 10c. The upper end of the outer tube 32 is located above the liquid level of the liquid intermediate medium LM accumulated in the second chamber 20c. The lower end of the outer tube 32 is located above the liquid level of the liquid intermediate medium LM accumulated in the first chamber 10c.

In the fifth modification, like the outer tube 32, the upper end of the inner tube 31 enters into the second chamber 20c, and the lower end enters into the first chamber 10c. Furthermore, although the space inside the inner tube 31 is used as the second flow path F2 functioning as a liquid flow path, the upper end of the inner tube 31 is connected to the liquid intermediate medium LM accumulated in the second chamber 20c. It is provided above the surface. For example, a concave guide is provided for guiding the liquid intermediate medium LM accumulated in the second chamber 20c from the outside of the outer tube 32 across the first flow path F1 to the second flow path F2 inside the inner tube 31. A groove (not shown) is formed. The guide groove is formed by cutting out the upper ends of the outer tube 32 and the inner tube 31 in a concave shape to a position below the liquid level when the communicating tube 30 is viewed in the radial direction. , is a groove that connects each notch like a gutter. This guide groove allows the liquid intermediate medium LM located below the upper end of the outer tube 32 in the second chamber 20c to be guided to the space inside the inner tube 31, that is, the second flow path F2. The second flow path F2 is a space inside the inner tube 31, and since it also functions as a liquid flow path in this modification, the second flow path F2 is located at the position where the guide groove connects to the inner tube 31. A second upper opening F2b of the channel F2 is formed. That is, the second upper opening F2b of the second flow path F2 is located below the liquid level of the liquid intermediate medium LM in the second chamber 20c. The lower end of the inner tube 31 is located below the lower end of the outer tube 32 and above the level of the liquid intermediate medium LM in the first chamber 10c.

Due to the aspect of the inner tube 31 and outer tube 32 in the fifth modification, the second flow path, which is the space inside the inner tube 31, can function as a liquid flow path, and the inner tube 31 and the outer tube 32 can function as a liquid flow path. The first flow path, which is the space between them, can function as a gas flow path.

The liquid reservoir 40 is provided below the second lower opening F2a of the second flow path F2 in the communication pipe 30 and above the liquid level of the liquid intermediate medium LM in the first chamber 10c. . In the fifth modification, the liquid reservoir 40 is arranged below the first lower opening F1a of the first flow path F1 while surrounding the second lower opening F2a of the second flow path F2. .

The upper edge 42 of the liquid reservoir 40 is located above the lower end of the inner tube 31 (the second lower opening F2a of the second flow path F2) and below the lower end of the outer tube 32. It is located in As a result, a gap is formed between the upper edge 42 of the liquid reservoir 40 and the lower end of the outer tube 32.

Then, the liquid intermediate medium LM overflows from the upper edge 42 of the liquid reservoir 40 and can flow downward from the gap, and at the same time, the gaseous intermediate medium GM generated in the first chamber 10c It becomes possible to flow from the gap into the first flow path F1 through the first lower opening F1a.

The liquid reservoir 40 may be provided in a space inside the inner tube 31 in the middle of the communication tube 30, for example, as in a sixth modification shown in FIG. That is, in the fifth modified example shown in FIG. 7, the liquid reservoir 40 is disposed below the lower end of the inner tube 31 in the first chamber 10c, whereas in the sixth modified example shown in FIG. , is arranged between the first chamber 10c and the second chamber 20c, and is also arranged in a space formed inside the inner tube 31.

The outer tube 32 of the communication tube 30 has an upper outer tube portion 32K connected to the second chamber 20c and a lower outer tube portion connected to the first chamber 10c, as in the fourth modification of FIG. 32M, and an outer tube enlarged diameter portion 32L provided to connect the outer tube upper portion 32K and the outer tube lower portion 32M. Note that, unlike the fourth modification shown in FIG. 6, the upper end of the outer tube upper part 32K is located above the liquid level of the liquid intermediate medium LM in the second chamber 20c.

Furthermore, in the sixth modification, the inner tube 31 of the communication tube 30 has an inner tube upper section 31K that enters into the second chamber 20c and forms a space between it and the outer tube upper section 32K, and a first chamber. The inner tube lower part 31M enters into the inner tube 10c and forms a space between it and the outer tube lower part 32M, and the outer tube has an enlarged diameter and is provided to connect the inner tube upper part 31K and the inner tube lower part 31M. It has an inner tube enlarged diameter portion 31L that forms a space between the inner tube portion 32L and the inner tube enlarged diameter portion 31L.

The diameter of the inner tube enlarged diameter portion 31L is larger than the diameters of the inner tube upper portion 31K and the inner tube lower portion 31M. That is, the inner tube enlarged diameter portion 31L has a top surface portion that extends radially outward from the outer surface of the inner tube upper portion 31K, and a top surface portion that extends downward from the outer peripheral edge of the top surface portion and is curved or bent radially inward at the extended end. and an outer wall portion connected to the upper end of the lower inner tube portion 31M. The inner tube enlarged diameter portion 31L covers the liquid reservoir portion 40.

The liquid reservoir part 40 is provided in the space formed by the inner tube enlarged diameter part 31L, and is formed in a downwardly convex shape. The bottom surface portion of the liquid reservoir portion 40 is disposed between the lower end of the inner tube upper portion 31K and the upper end of the inner tube lower portion 31M in the space formed inside the inner tube enlarged diameter portion 31L, and extends in the radial direction. Extends. The vertical wall portion of the liquid reservoir portion 40 extends outside the inner tube upper portion 31K from the outer peripheral end of the bottom portion to above the lower end of the inner tube upper portion 31K. The upper edge portion 42 of the vertical wall portion forms a gap with the top surface portion of the inner tube enlarged diameter portion 31L. The vertical wall portion forms a gap with the outer wall portion of the inner tube enlarged diameter portion 31L. Furthermore, the vertical wall portion forms a gap in the radial direction between the vertical wall portion and the inner tube upper portion 31K.

The upper flow path portion F21 of the second flow path F2 is a space formed inside the inner tube upper portion 31K in the sixth modification. The lower end portion F21s of the upper flow path portion F21 is formed by the lower end portion of the inner tube upper portion 31K.

The lower flow path portion F22 of the second flow path F2 includes a portion formed by the upper edge portion 42 of the vertical wall portion of the liquid reservoir portion 40 and the top surface portion of the inner tube enlarged diameter portion 31L, and a portion formed by the liquid reservoir portion 40. It includes a portion formed by the outer wall portion of the inner tube enlarged diameter portion 31L and a portion formed inside the inner tube lower portion 31M. The upper end portion F22t of the lower flow path portion F22 is formed as a space between the upper edge portion 42 of the liquid reservoir portion 40 and the top surface portion of the inner tube enlarged diameter portion 31L.

In the intermediate medium heat exchanger 1 according to the sixth modification, the space inside the inner pipe 31 of the communication pipe 30 serves as the second flow path F2 that functions as a liquid flow path. Similar to the fourth modification (FIG. 6) in which a liquid reservoir 40 is provided in the middle, the upper flow path F21 of the second flow path F2 is sealed by the liquid reservoir 40.

In the first embodiment and its modifications, the intermediate medium heat exchanger 1 includes one communication pipe 30, but the structure is not limited to one communication pipe 30, and may include a plurality of communication pipes 30. There may be. Here, a seventh modification example including a plurality of communication pipes 30 will be described based on FIG. 9.

The intermediate medium heat exchanger 1 according to the seventh modification includes a first communication pipe 30 and a second communication pipe 30B. The first communication pipe 30 and the second communication pipe 30B each have the same configuration as the communication pipe 30 described above. That is, the first communication pipe 30 and the second communication pipe 30B may have the configuration of the communication pipe 30 disclosed in the first embodiment (FIGS. 1 and 2), or may have the structure of the communication pipe 30 disclosed in the first embodiment (FIGS. 1 and 2), or may have the structure of the communication pipe 30 disclosed in the first embodiment (FIGS. 1 and 2), or The structure of the communication pipe 30 disclosed in the example to the sixth modification (FIGS. 3 to 8) may be provided.

Since the intermediate medium heat exchanger 1 according to the seventh modification includes the plurality of communication pipes 30, the amount of intermediate medium circulated between the intermediate medium evaporator E1 and the liquefied gas vaporizer E2 can be increased. This makes it possible to improve the efficiency of the intermediate medium heat exchanger 1.

As shown in FIG. 10, in the intermediate medium heat exchanger 1 according to the eighth modification, the inner tube 31 and the outer tube 32 of the communication tube 30 are provided with a heat insulating material. That is, as shown in FIG. 11, which is an enlarged view of region XI in FIG. It is configured as a triple-structured heat-insulating pipe in which the heat-insulating materials 31C arranged in the pipe are stacked on top of each other. The outer tube 32 is provided with a heat insulating material 32C at a portion that comes into contact with the atmosphere. Note that the heat insulating materials 31C and 32C have a thermal conductivity that is 1/100 or less of the thermal conductivity of the inner tube 31A, the outer tube 31B, and the outer tube 32, and are made of, for example, glass wool, rock wool, or polystyrene foam. and rigid urethane foam.

The heat insulating material 31C of the inner tube 31 can suppress the gaseous intermediate medium GM in the first flow path F1 from being cooled and liquefied by the liquid intermediate medium LM in the second flow path F2. This suppresses the occurrence of a flooding phenomenon in the first flow path F1 and a decrease in the amount of circulation of the intermediate medium due to an increase in flow path resistance. Furthermore, a decrease in the vaporization efficiency of the gaseous intermediate medium GM in the liquefied gas vaporizer E2 is suppressed.

The heat insulating material 31C of the inner pipe 31 and the heat insulating material 32C provided in the outer pipe 32 cause the liquid intermediate medium LM in the second flow path F2 to be warmed by the atmosphere and the gaseous intermediate medium GM in the first flow path F1. This prevents the liquid from being exposed to water and vaporizing. This suppresses the occurrence of a flooding phenomenon in the second flow path F2 and the decrease in the circulation amount of the intermediate medium due to an increase in flow path resistance. Furthermore, since it is possible to suppress the liquid intermediate medium LM in the second flow path F2 from being cooled by the atmosphere, a decrease in the evaporation efficiency of the liquid intermediate medium LM in the intermediate medium evaporator E1 is suppressed.

Note that the heat insulating material may be provided in only one of the inner tube 31 and the outer tube 32.

Further, the inner tube 31 may be configured as a triple-layer heat-insulated tube using a heat insulating material only at the portion that contacts the second flow path F2.

Further, although the outer tube 32 is provided with a heat insulating material 32C at a portion that comes into contact with the atmosphere, the present invention is not limited thereto. For example, like the inner tube 31, the outer tube 32 has a triple structure in which an inner tube, an outer tube placed outside the inner tube, and a heat insulating material placed between the inner tube and the outer tube are layered. It may be configured as an insulated pipe.

Further, similarly to the inner tube 31, the vertical wall portion and the bottom portion of the liquid reservoir portion 40 have a triple structure in which an inner member, an outer member, and a heat insulating material disposed between the inner member and the outer member are stacked. It may be configured as a heat insulating member.

(Second embodiment)
Next, an intermediate medium heat exchanger 1 according to a second embodiment will be described based on FIG. 12 . Note that in the second embodiment, the same components as those in the first embodiment described above are designated by the same reference numerals, and the description thereof will be omitted, and the explanation will mainly be given to the different components.

Also in the intermediate medium heat exchanger 1 according to the second embodiment, the inside of the first chamber 10c and the inside of the second chamber 20c are communicated with each other through the communication tube 30 having a multi-tube structure.

In the communication pipe 30 in the second embodiment, the inner space of the inner pipe 31 is used as a second flow path F2 that functions as a liquid flow path, and the space between the inner pipe 31 and the outer pipe 32 is used as a second flow path F2 that functions as a gas flow path. There is one flow path F1.

The lower end of the inner tube 31 is lower than the lower end of the outer tube 32 and lower than the liquid level of the liquid intermediate medium LM accumulated in the first chamber 10c. That is, the second lower opening F2a of the second flow path F2 is arranged at a position below the liquid level of the liquid intermediate medium LM in the first chamber 10c. Therefore, the second lower opening F2a is immersed in the liquid intermediate medium LM.

In the intermediate medium heat exchanger 1 according to the second embodiment, the second lower opening F2a, which is the lower end of the second flow path F2 functioning as a liquid flow path, is configured to open the second lower opening F2a, which is the lower end of the second flow path F2, which functions as a liquid flow path. Since it is immersed in the intermediate medium LM, the second flow path F2 can be operated in a state where the entire second flow path F2 is filled with the liquid intermediate medium LM. Therefore, even if the gaseous intermediate medium GM flows into the second flow path F2, a state where the liquid intermediate medium LM easily flows in the second flow path F2 is maintained, and the second flow path F2 It can continue to function as a liquid flow path.

Note that the communication pipe 30 is not limited to the form shown in FIG. 12 . For example, as in the first modification shown in FIG. 13 , the inner tube 31 is not formed in a straight tube shape in the first chamber 10c, but in a horizontal direction, for example, in a direction perpendicular to the extending direction of the first heat exchanger tube 10d ( It may also be bent in the left-right direction in FIG. 13 to form a crank shape.

The second lower opening F2a of the second flow path F2 is located at a position below the liquid level of the liquid intermediate medium LM in the first chamber 10c, and is located at a position below the liquid level of the liquid intermediate medium LM, and It is arranged at a position shifted laterally from directly above 10d.

When the second lower opening F2a of the second flow path F2 immersed in the liquid intermediate medium LM in the first chamber 10c is arranged directly above the first heat exchanger tube 10d, the first The gaseous intermediate medium GM generated from the heat transfer tube 10d may flow into the second lower opening F2a. On the other hand, in the intermediate medium heat exchanger 1 according to the first modification, the second lower opening F2a is disposed at a position shifted laterally from directly above the first heat exchanger tube 10d. The gaseous intermediate medium GM is suppressed from flowing into the second flow path F2 from the second lower opening F2a.

In a configuration in which the lower end of the communication tube 30 is located directly above the first heat exchanger tube 10d, a gas inflow suppressing member 50 is provided as in the second modification shown in FIG . 14 and the third modification shown in FIG. You can. The gas inflow suppressing member 50 prevents the gaseous intermediate medium GM in the first chamber 10c from flowing into the second flow path F2 through the second lower opening F2a.

The gas inflow suppressing member 50 is a plate-shaped member arranged to extend horizontally between the second lower opening F2a and the first heat exchanger tube 10d. That is, the gas inflow prevention member 50 is a gas inflow prevention plate having a portion located below the second lower opening F2a of the second flow path F2. The gas inflow suppressing member 50 has a sufficient area to cover the second lower opening F2a and make it invisible when viewed upward from the bottom surface of the first chamber 10c.

In the intermediate medium heat exchanger 1 according to the second modification of the second embodiment shown in FIG. 14 and the third modification shown in FIG. Even if the gaseous intermediate medium GM generated in the heat transfer tube 10d floats in the liquid, it is prevented from flowing into the second flow path F2 through the second lower opening F2a.

On the other hand, in the second embodiment as well, as in the fourth modification shown in FIG . The space between them may be used as a second flow path F2 that functions as a liquid flow path.

In the fourth modification, the outer tube 32 forming the second flow path F2 is not shaped like a straight tube in the first chamber 10c, but is arranged so as to be separated from the inner tube 31 in the radial direction, for example, in the first heat exchanger tube 10d. It may be bent in a direction perpendicular to the extending direction (left-right direction in FIG. 16 ) to form a crank shape.

While the outer tube 32 is bent within the first chamber 10c and extends away from the inner tube 31 to a position below the liquid level of the liquid intermediate medium LM, the first flow path formed by the inner tube 31 The first lower opening F1a of F1 is located above the liquid level. For this reason, the communication pipe 30 further includes an intermediate wall 33. The intermediate wall 33 is located between the intermediate wall 33 and the tube wall of the outer tube 32 at a position below the position where the outer tube 32 bends outward in the radial direction and at a position above the second lower opening F2a. A portion extending radially outward from the inner tube 31 at a necessary interval as a second flow path, and a portion bent downward from this portion and lower than the liquid level of the liquid intermediate medium LM in the first chamber 10c. and a portion extending to a lower position. As a result, a space as the second flow path F2 is secured between the intermediate wall 33 and the outer tube 32, and at the same time, the gaseous intermediate medium GM is allowed to flow between the intermediate wall 33 and the inner tube 31 under the first flow path F2. A space for heading toward the side opening F1a is secured.

That is, the space formed between the outer tube 32 and each of the inner tube 31 and the intermediate wall 33 becomes the second flow path F2. The second flow path F2 is bent as the outer tube 32 and the intermediate wall 33 are bent, and extends to a position shifted laterally from directly above the first heat exchanger tube. The second lower opening F2a of the second flow path F2 is located at a position below the liquid level of the liquid intermediate medium LM in the first chamber 10c, and from directly above the first heat exchanger tube to the side. It is placed at a position shifted to the side.

In the intermediate medium heat exchanger 1 according to the fourth modification, as in the first modification of the second embodiment described above, the second lower opening F2a is connected to the first heat exchanger tube in the first chamber 10c. 10d, the gaseous intermediate medium GM is suppressed from flowing into the second flow path F2 from the second lower opening F2a.

Further, FIG . 17 shows a fifth modification of the second embodiment in which a gas inflow suppressing member 50 is further provided in the fourth modification shown in FIG.

That is, the intermediate medium evaporator E1 further includes a gas inflow suppressing member 50 disposed between the second lower opening F2a of the second flow path F2 and the first heat exchanger tube 10d.

Thereby, the gaseous intermediate medium GM is more effectively prevented from flowing into the second flow path F2 through the second lower opening F2a.

Next, other modified examples (not shown) of the first embodiment and the second embodiment will be shown.

In the second embodiment and its modified examples, the intermediate medium heat exchanger 1 may include a plurality of communication pipes 30. Also in this case, the amount of circulation of the intermediate medium throughout the intermediate medium heat exchanger 1 can be increased, and the efficiency of the intermediate medium heat exchanger 1 can be improved.

In the communication pipe 30, the diameters of the inner pipe 31 and the outer pipe 32 may be set such that the hydraulic diameter of the first flow path F1 is larger than the hydraulic diameter of the second flow path F2. The pressure loss in the first flow path F1 functioning as a gas flow path is greater than the pressure loss in the second flow path F2 functioning as a liquid flow path. Therefore, if the hydraulic diameter of the first flow path F1 is larger than the hydraulic diameter of the second flow path F2, it is possible to suppress pressure loss due to the first flow path F1. When the pressure loss in the first flow path F1 is suppressed, the liquid level height in the second flow path F2 is suppressed, so that the length of the communication pipe 30 can be further shortened.

Note that the hydraulic diameter (D _H ) is a length defined as follows.
D _H =4A/P
Here, A is the cross-sectional area of the flow, and P is the circumference of the wetted part (wetted edge) of the cross-section.

The hydraulic diameter of the flow path formed in the inner tube 31 is equal to the inner diameter of the inner tube 31 when the inner tube 31 is a circular tube. When the inner tube 31 and the outer tube 32 are both circular tubes, the hydraulic diameter D _Hr of the flow path formed between the inner tube 31 and the outer tube 32 is defined as the cross-sectional area of the flow path A _r , When the outer diameter of the inner tube 31 is _D1 and the inner diameter of the outer tube 32 is _D2 ,
D _Hr =4A _r /{π×(D ₁ +D ₂ )}
It is calculated as .

Although the communication pipe 30 has been described above as having a double pipe structure consisting of an inner pipe 31 and an outer pipe 32, it is not limited to a communication pipe with a double pipe structure, and may have a structure with multiple pipes of double pipe or more. It may also be a communicating pipe. In this case, which of the plurality of spaces separated by the plurality of pipes that overlap in the radial direction in the communication pipe is used as the liquid flow path and which is used as the gas flow path is arbitrary and is not limited. do not have.

Furthermore, regarding the communication pipe 30, in the above description, it is assumed that the shape is symmetrical in the radial direction, except for the first modification and the third modification of the second embodiment of the present invention shown in FIGS. 13 and 15 . Although the above description has been made, as long as the communicating tube has a multi-tube structure, it may have an asymmetric shape in the radial direction. For example, regarding the communication tube 30, the center axis of the inner tube 31 and the center axis of the outer tube 32 may not overlap, but may be eccentric. Further, both or one of the inner tube 31 and the outer tube 32 may not be a circular tube.

Further, regarding the liquid reservoir 40, in the first modification of the first embodiment shown in FIG. 3, the shape includes a curved surface that bends the downward flow of the liquid intermediate medium LM passing through the liquid reservoir 40 into an upward flow. Although the explanation has been made assuming that the liquid reservoir portion 40 may be formed in a curved shape, the liquid reservoir portion 40 in other modified examples may be similarly formed in a shape including a curved surface.

As shown in FIG. 18, in the intermediate medium heat exchanger 1 according to the sixth modification, the inner tube 31 and the outer tube 32 of the communication tube 30 are provided with a heat insulating material. Similar to the eighth modification of the first embodiment shown in FIGS. 10 and 11, the inner tube 31 includes an inner tube 31A, an outer tube 31B disposed outside the inner tube 31A, and an inner tube 31A. The outer tube 31B is configured as a triple-structured heat insulating tube in which a heat insulating material 31C disposed between the outer tubes 31B and the outer tube 31B are overlapped. The outer tube 32 is provided with a heat insulating material 32C at a portion that comes into contact with the atmosphere.

The heat insulating material 31C of the inner tube 31 can prevent the liquid intermediate medium LM in the second flow path F2 from being heated and vaporized by the gaseous intermediate medium GM in the first flow path F1. This suppresses a decrease in the circulation amount of the intermediate medium in the second flow path F2 due to the occurrence of a flooding phenomenon and an increase in flow path resistance.

The heat insulating material 31C of the inner pipe 31 and the heat insulating material 32C provided in the outer pipe 32 allow the gaseous intermediate medium GM in the first flow path F1 to be absorbed by the atmosphere and the liquid intermediate medium LM in the second flow path F2. It can suppress cooling and liquefaction. This suppresses the occurrence of a flooding phenomenon in the first flow path F1 and the decrease in the circulation amount of the intermediate medium due to an increase in flow resistance of the first flow path F1. Furthermore, a decrease in the vaporization efficiency of the gaseous intermediate medium GM in the liquefied gas vaporizer E2 is suppressed.

Note that the heat insulating material may be provided in only one of the inner tube 31 and the outer tube 32.

Further, the inner tube 31 may be configured as a triple-layer heat-insulated tube using a heat insulating material only at the portion that contacts the first flow path F1.

Further, although the outer tube 32 is provided with a heat insulating material 32C at a portion that comes into contact with the atmosphere, the present invention is not limited thereto. For example, like the inner tube 31, the outer tube 32 has a triple structure in which an inner tube, an outer tube placed outside the inner tube, and a heat insulating material placed between the inner tube and the outer tube are layered. It may be configured as an insulated pipe.

1 Intermediate medium heat exchanger E1 Intermediate medium evaporator 10c First chamber 10d First heat exchanger tube E2 Liquefied gas vaporizer 20c Second chamber 20d Second heat exchanger tube 30 (First) communication tube 30B Second Communication pipe 31 Inner pipe 31A Inner pipe 31B Outer pipe 31C, 32C Insulating material 31K Inner pipe upper part 31L Inner pipe enlarged diameter part 31M Inner pipe lower part 32 Outer pipe 32K Outer pipe upper part 32L Outer pipe enlarged diameter part 32M Outside Pipe lower side 33 Intermediate wall 34 Liquid inflow suppressing member 35 Lower end of liquid inflow suppressing member 40 Liquid reservoir 41 Bottom of liquid reservoir 42 Upper edge of bottom of liquid reservoir 43 Top of liquid reservoir 50 Gas inflow Suppressing member F1 First flow path F1a First lower opening F1b First upper opening F2 Second flow path F21 Upper flow path portion of the second flow path F21s Lower end portion of the upper flow path F22 Bottom of the second flow path Side flow path portion F22t Upper end of lower flow path portion F2a Second lower opening F2b Second upper opening 50 Gas inflow suppression member (gas inflow suppression plate)
LM Liquid intermediate medium GM Gaseous intermediate medium

Claims (17)

an intermediate medium evaporator having a hollow first chamber; and a first heat transfer tube arranged to pass through the first chamber and into which a heat source medium flows;
A liquefier comprising: a hollow second chamber disposed above the first chamber; and a second heat transfer tube disposed to pass through the second chamber and into which low-temperature liquefied gas flows. gas vaporizer;
a communication tube having a multi-tube structure including an inner tube and an outer tube disposed radially outside the inner tube, and communicating the inside of the first chamber and the inside of the second chamber with each other;
Equipped with
An intermediate medium is enclosed in a space formed by the first chamber, the second chamber, and the communication pipe,
The liquid intermediate medium in the first chamber is heated by the heat source medium through the first heat exchanger tube and is vaporized to become a gaseous intermediate medium,
The gaseous intermediate medium in the second chamber is cooled and condensed into the low-temperature liquefied gas through the second heat transfer tube, and becomes a liquid intermediate medium;
When one of the space inside the inner tube and the space between the inner tube and the outer tube is used as a first flow path and the other is used as a second flow path,
The first flow path is
a first upper opening that opens at a position above the liquid level of the liquid intermediate medium in the second chamber;
a first lower opening opening at a position above the liquid level of the liquid intermediate medium in the first chamber;
and functions as a gas flow path through which a gaseous intermediate medium flows,
The second flow path is
a second upper opening that opens at a position below the liquid level of the liquid intermediate medium in the second chamber;
a second lower opening opening within the first chamber;
and functioning as a liquid flow path through which the liquid intermediate medium flows in a state where it is at least partially filled with the liquid intermediate medium.
Intermediate medium heat exchanger. The second flow path further includes a liquid reservoir section that is provided at a position above the liquid level of the liquid intermediate medium in the first chamber and that stores the liquid intermediate medium.
The intermediate medium heat exchanger according to claim 1. The liquid reservoir is
While storing the liquid intermediate medium flowing out from the second lower opening of the second flow path, the upper edge located above the second lower opening stores the accumulated liquid intermediate medium. It is configured so that it overflows from the
The intermediate medium heat exchanger according to claim 2. The second flow path includes an upper flow path portion that extends downward from the second upper opening portion, and an upper flow path portion that extends upward from the second lower opening portion, and has an upper end portion that is higher than a lower end portion of the upper flow path portion. further comprising a lower flow path portion located therein;
The liquid reservoir stores the liquid intermediate medium flowing out from the lower end of the upper flow path, and allows the collected liquid intermediate medium to flow into the upper end of the lower flow path. It is configured as follows.
The intermediate medium heat exchanger according to claim 2. The liquid reservoir is formed in a shape including a curved surface that bends a downward flow of the liquid intermediate medium passing through the liquid reservoir into an upward flow.
The intermediate medium heat exchanger according to claim 3 or 4. The first flow path is formed as a space inside the inner tube of the communication tube, and the second flow path is formed as a space between the inner tube and the outer tube,
The communication pipe allows the liquid intermediate medium that has flowed out of the liquid reservoir to pass through the first lower opening on the flow of the gaseous intermediate medium that is about to enter the first lower opening. further comprising a liquid inflow prevention member that prevents liquid from flowing into the first flow path;
The intermediate medium heat exchanger according to any one of claims 2 to 5. The liquid inflow suppressing member extends downward from the liquid reservoir and has a lower end portion located below the first lower opening of the first flow path.
The intermediate medium heat exchanger according to claim 6. The liquid inflow prevention member is inclined with respect to the vertical direction so as to be radially away from the first lower opening of the first flow path.
The intermediate medium heat exchanger according to claim 6 or 7. The liquid inflow prevention member is formed continuously or discontinuously in the circumferential direction of the first flow path so as to surround the first lower opening of the first flow path.
The intermediate medium heat exchanger according to any one of claims 6 to 8. The second lower opening of the second flow path is disposed at a position below the liquid level of the liquid intermediate medium in the first chamber, so that it is immersed in the liquid intermediate medium. ing,
The intermediate medium heat exchanger according to claim 1. The second lower opening of the second flow path is located in the first chamber at a position shifted laterally from directly above the first heat exchanger tube.
The intermediate medium heat exchanger according to claim 10. The intermediate medium evaporator further includes a gas inflow prevention member that prevents the gaseous intermediate medium in the first chamber from flowing into the second flow path through the second lower opening.
The intermediate medium heat exchanger according to claim 10 or 11. The hydraulic diameter of the first flow path is larger than the hydraulic diameter of the second flow path.
The intermediate medium heat exchanger according to any one of claims 1 to 12. The first upper opening and the first lower opening of the first flow path are formed in a reverse tapered shape to increase the opening diameter.
The intermediate medium heat exchanger according to any one of claims 1 to 13. The second upper opening of the second flow path is formed in a reverse tapered shape to increase the opening diameter.
The intermediate medium heat exchanger according to any one of claims 1 to 14. It has a multi-tube structure including an inner tube and an outer tube disposed radially outside the inner tube, and communicates the inside of the first chamber and the inside of the second chamber with each other, and the inside of the inner tube. and a second communication pipe in which one of the spaces between the inner tube and the outer tube is the first flow path and the other is the second flow path,
The intermediate medium heat exchanger according to any one of claims 1 to 15. At least one of the inner tube and the outer tube is provided with a heat insulating material,
The intermediate medium heat exchanger according to any one of claims 1 to 16.