JP5714944B2 - Low temperature liquefied gas vaporizer - Google Patents

Description

The present invention relates to a vaporizer for vaporizing a low-temperature liquefied gas such as liquefied natural gas (LNG), liquefied petroleum gas (LPG), or liquid nitrogen (LN ₂ ) by heat exchange with a heat medium such as seawater.

  DESCRIPTION OF RELATED ART Conventionally, what is described in patent document 1 is known as a vaporizer (ORV) which heat-exchanges liquefied natural gas (LNG) with seawater (liquid for heat exchange), and vaporizes it.

  As shown in FIG. 11, the vaporizer has a vaporization tube panel 102 extending along a specific vertical plane and seawater from the upper end of the vaporization tube panel 100 so as to flow down along the surface of the vaporization tube panel 100. A seawater supply unit 104 to supply.

  The vaporization tube panel 102 includes a plurality of vaporization tubes (heat transfer tubes) 106 for evaporating liquefied natural gas (low-temperature liquefied gas) flowing in the vertical direction and flowing inside by heat exchange with the outside, and the inside of the vaporization tube panel 102. The vaporizer pipes 106 (distribution side headers) 108 for distributing the liquefied natural gas to the vaporizer pipes 106 are provided. The plurality of vaporization tubes 106 included in the vaporization tube panel 102 are arranged in the horizontal direction on the specific vertical plane so as to be parallel to each other. The inter-vaporization pipe distribution pipe 108 extends in the horizontal direction and is connected to the lower end portion of each vaporization pipe 106 included in the vaporization pipe panel 102.

  In such a vaporizer, the liquefied natural gas distributed to each vaporizer pipe 106 by the vaporizer pipe distribution pipe 108 rises in the vaporizer pipe 106, and the seawater supplied from the seawater supply unit 104 is vaporized pipe 106. And flow down along the vaporizing tube 106. At this time, in each vaporization pipe 106, the liquefied natural gas and seawater exchange heat through a pipe wall that separates the inside and the outside of the vaporization pipe 106, whereby the liquefied natural gas is vaporized and natural gas (NG )

  Moreover, what is described in patent document 2 is known as a vaporizer. In this vaporizer, as shown in FIG. 12, a waterproof cover 110 is placed on the upper side of the first region a1 of the inter-vaporization pipe distribution pipe. The waterproof cover 110 prevents seawater from directly hitting the first region a1 of the inter-vaporization pipe distribution pipe 108, and suppresses heat fluctuation of the vaporized liquefied natural gas when the temperature of the seawater is relatively high and the load is small. Can do.

JP-A-57-57998 JP 08-183970 A

  In the vaporization apparatus of Patent Document 1, when the low-temperature liquefied gas (liquefied natural gas) is vaporized, the longitudinal end portion (region a2 in FIG. 11) and the central portion of the distribution pipe 108 between the vaporization pipes 108. There is a case where a temperature difference occurs between (a region a2 in FIG. 11) and the vaporization pipe distribution pipe 108 is bent due to a difference in thermal expansion / contraction amount of each vaporization pipe 106 due to this. As a result, the inter-vaporization pipe distribution pipe 108 is bent, and a stress is generated at the joint portion between the vaporization pipe distribution pipe 108 and each vaporization pipe 106.

  Specifically, in the longitudinal direction of the inter-vaporization pipe distribution pipe 108, the temperature of the end a <b> 2 outside the region a <b> 1 where the plurality of vaporization pipes 106 are arranged, i.e., the longitudinal direction of the inter-vaporization pipe distribution pipe 108 is It becomes higher than the temperature of the region a1. This is sufficient when the heat exchange liquid (seawater) flowing down the first region a1 along the vaporization tube panel 102 flows down to the vaporization pipe distribution pipe 108 by heat exchange with the low-temperature liquefied gas in the vaporization pipe 106. However, since the heat exchange liquid that flows down outside the vaporization tube panel 102 in the longitudinal direction flows with little heat exchange with the low-temperature liquefied gas in the vaporization tube 106, the first temperature is low. This is because the temperature when reaching the vaporizing pipe distribution pipe 108 is higher than that of the heat exchange liquid flowing down the area a1. Thus, when a temperature difference occurs between the first region a1 and the second region a2 of the inter-vaporization pipe distribution pipe 108, the vaporization pipe distribution pipe 108 is connected to the vaporization pipe 106 at the end position in the longitudinal direction. There is a difference between the temperature of the low-temperature liquefied gas distributed and the temperature of the low-temperature liquefied gas distributed to the vaporization pipe 106 at the central position in the longitudinal direction of the first region a1. As a result, a difference in thermal expansion and contraction occurs between the vaporization pipe 106 at the end position and the vaporization pipe 106 at the central position, and thereby the vaporization pipe distribution pipe 108 is bent.

  On the other hand, in the vaporizer described in Patent Document 2, it is possible to prevent the heat exchange liquid from directly hitting the first region a1 of the inter-vaporization pipe distribution pipe. However, since the waterproof cover 110 covers only the portion adjacent to the vaporization pipe 106 at the end position in the horizontal direction in the second region a2 of the vaporization pipe distribution pipe 108, the vaporization apparatus also includes the vaporization pipe division. The heat exchange liquid that does not exchange heat with the low-temperature liquefied gas (high temperature) hits the second region a2 of the pipe 108. Therefore, also in the vaporizer, there is a temperature difference between the first region a1 and the second region a2 of the inter-vaporization pipe distribution pipe 108, and, similar to the vaporization apparatus of Patent Document 1, the inter-vaporization pipe distribution pipe. There is a concern that 108 may bend.

  Therefore, in view of the above problems, the present invention has an object to provide a vaporizer for low-temperature liquefied gas in which bending of an inter-vaporization pipe distribution pipe is unlikely to occur due to a difference in temperature in the longitudinal direction of the inter-vaporization pipe distribution pipe. To do.

Therefore, in order to solve the above-mentioned problems, the present invention is an apparatus for vaporizing a low-temperature liquefied gas, which evaporates the low-temperature liquefied gas extending in the vertical direction and flowing inside by heat exchange with the outside. A plurality of vaporizing pipes and pipes between the vaporizing pipes for distributing the low-temperature liquefied gas to each of the vaporizing pipes, the plurality of vaporizing pipes arranged in a horizontal direction on a vertical plane, and the pipes between the vaporizing pipes A vaporization tube panel extending in the horizontal direction and connected to a lower end portion of each vaporization tube, and a liquid for supplying heat exchange liquid from the upper end portion of the vaporization tube panel so as to flow down along the plurality of vaporization tubes Compared to the temperature of the heat exchange liquid flowing down toward the first region of the supply pipe and the inter-vaporization tube distribution pipe in which the plurality of vaporization tubes are arranged, it is outside the first region in the horizontal direction. Above Even if the direction of the temperature of the heat exchange fluid flows down towards the second region between distribution pipe tract high, the amount of heat transfer per unit area from the heat transfer fluid that Tsutawa to the first region compared to, and a heat transfer suppressing section for suppressing heat transfer to the following comparable per unit area from the previous SL heat transfer fluid that Tsutawa the second region. Note that the heat transfer amount is approximately equal to or less than that when the heat is transferred from the heat exchange liquid to the low-temperature liquefied gas flowing through the vaporization pipe distribution pipe, the low-temperature liquefied gas flowing through the second region of the vaporization pipe distribution pipe. Not only when the temperature is the same or lower than the temperature of the low-temperature liquefied gas flowing in the first region, but also slightly lower than the temperature of the low-temperature liquefied gas flowing in the first region to the extent that it does not affect the bending of the pipe between the vaporization tubes. This includes cases where the price is too high.

  According to the present invention, even if the temperature of the heat exchange liquid flowing down toward the second region of the vaporization pipe distribution pipe is higher than the heat exchange liquid flowing down toward the first area of the vaporization pipe distribution pipe, Since the amount of heat transfer per unit area from the heat exchange liquid in the entire second region is suppressed by the heat transfer suppression unit, the heat exchange liquid having a different temperature is second than the first region of the inter-vaporization pipe distribution pipe. It becomes possible to prevent the region from becoming hot. As a result, the temperature difference between the low-temperature liquefied gas distributed from the distribution pipe between the vaporization pipes to the vaporization pipe at the end position in the horizontal direction of the vaporization pipe panel and the low-temperature liquefied gas distributed to the vaporization pipe at the central position. And the bending of the pipe between the vaporization pipes due to the amount of thermal expansion and contraction of each vaporization pipe is prevented.

  Specifically, for example, the heat transfer suppression portion is a heat insulating member surrounding the second region of the inter-vaporization pipe distribution pipe, and the thermal conductivity of the heat insulation member is smaller than the thermal conductivity of the inter-vaporization pipe distribution pipe. To do. Then, by enclosing the second region of the inter-vaporization pipe distribution pipe with this heat insulating member, compared with the heat transfer amount per unit area from the heat exchange liquid in the first area of the inter-vaporization pipe distribution pipe, in the second region The amount of heat transfer per unit area from the heat exchange liquid can be easily and reliably suppressed.

  Further, in the vaporizer, the heat insulating member has a predetermined stretchability, so that the heat insulating member can be prevented from being damaged due to the heat expansion and contraction of the distribution pipe between the vaporization tubes. Specifically, the distribution pipe between the vaporization pipes is in a state where the low-temperature liquefied gas is flowing (that is, during operation of the vaporizer) and a state where the low-temperature liquefied gas is not flowing (that is, when the vaporizer is stopped). The heat insulating member surrounding the vaporizing pipe distribution pipe expands and contracts in accordance with the heat expansion and contraction of the vaporization pipe distribution pipe. Thereby, the damage of the heat insulation member resulting from the thermal expansion / contraction (especially radial thermal expansion / contraction) of the distribution pipe between vaporization pipes can be prevented effectively.

  The heat transfer suppression unit of the vaporizer may be a cover member that is disposed above the second region of the inter-vaporization pipe distribution pipe and has a shape that covers the second area of the distribution pipe in plan view.

  According to such a configuration, the heat hardly flows with the low-temperature liquefied gas flowing down outside the vaporizing pipe at the end position in the longitudinal direction (horizontal direction) of the pipe between the vaporizing pipes and flowing through the vaporizing pipe. The replacement liquid can be prevented from hitting the second region of the inter-vaporization pipe distribution pipe. Thereby, it becomes possible to prevent a difference in temperature between the first region and the second region of the distribution pipe between the vaporization tubes.

  In addition, when the site | part between the edge part in the said distribution pipe between vaporization pipes and the vaporization pipe located in the said edge part side penetrates a partition wall, the said 2nd area | region is on the said partition wall and the said edge part side. This is the area up to the vaporization tube.

  Further, in order to solve the above-mentioned problems, the present invention is an apparatus for vaporizing a low-temperature liquefied gas, which evaporates the low-temperature liquefied gas extending in the vertical direction and flowing inside by heat exchange with the outside. A plurality of vaporizing pipes and pipes for dividing the low-temperature liquefied gas to each of the vaporizing pipes, and the plurality of vaporizing pipes are arranged in a horizontal direction on a specific vertical plane and are arranged between the vaporizing pipes. Supply a heat exchange liquid from the upper end of the vaporization tube panel so that the pipe extends in the horizontal direction and is connected to the lower end of each vaporization tube, and flows down along the plurality of vaporization tubes. A liquid supply unit. And, in the second region of the inter-vaporization tube distribution pipe outside the first region in the horizontal direction, rather than the tube wall in the first region of the inter-vaporization tube distribution tube in which the plurality of vaporization tubes are arranged. The tube wall has lower thermal conductivity.

  According to the present invention, since the thermal conductivity of the tube wall is smaller in the second region than in the first region of the vaporization pipe distribution pipe, the heat exchange has a higher temperature than the first region of the vaporization pipe distribution pipe. Even if the liquid hits the second region of the inter-vaporization pipe distribution pipe, the temperature is between the temperature of the low-temperature liquefied gas flowing inside the first area of the inter-vaporization pipe distribution pipe and the temperature of the low-temperature liquefied gas flowing inside the second area. It becomes possible to prevent the difference of. As a result, it is possible to prevent the vaporization pipe distribution pipe from being bent due to this temperature difference.

  As described above, according to the present invention, it is possible to provide a vaporizer for low-temperature liquefied gas in which bending of the inter-vaporization pipe distribution pipe is less likely to be caused by a difference in temperature in the longitudinal direction of the inter-vaporization pipe distribution pipe.

It is a schematic structure perspective view of the vaporizer of the low-temperature liquefied gas concerning this embodiment. It is a schematic diagram (front view) which shows the state of piping of the said vaporization apparatus. It is a schematic diagram (side view) which shows the state of piping of the said vaporization apparatus. It is the elements on larger scale for demonstrating the heat transfer suppression part of the said vaporization apparatus. (A) is a side view for demonstrating the seawater supply part of the said vaporization apparatus, (B) is a front view for demonstrating the seawater supply part of the said vaporization apparatus. It is a figure which shows the state in which the said vaporization apparatus was installed, Comprising: It is the perspective view which fractured | ruptured one part. It is a figure which shows the difference in the temperature of the liquefied natural gas which flows through the inside of the supply side header by the thickness of a heat insulation member. It is a longitudinal cross-sectional view for demonstrating the heat insulation member (heat transfer suppression part) which concerns on other embodiment. It is an expanded cross-sectional view for demonstrating the cover member in the vaporization apparatus of the low temperature liquefied gas of other embodiment. It is an expanded transverse cross section of the 2nd field of distribution pipe between vaporization pipes in the vaporization device of low-temperature liquefied gas of other embodiments. It is a partial expansion perspective view for demonstrating the conventional vaporization apparatus. It is a partial expansion perspective view for demonstrating the conventional vaporization apparatus.

  Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

  The low-temperature liquefied gas vaporizer according to the present embodiment (hereinafter, also simply referred to as “vaporizer”) exchanges the supplied low-temperature liquefied gas with an external heat exchange liquid, thereby This is a so-called open rack type vaporizer (ORV) for vaporization. In the vaporizer of this embodiment, liquefied natural gas (LNG) is vaporized. In this embodiment, seawater is used as the heat exchange liquid.

  Specifically, as shown in FIGS. 1 to 5, the vaporizer includes a plurality of (two in this embodiment) vaporizer tube blocks 11, a distribution pipe 12 that distributes LNG to each vaporizer tube block 11, and A collection pipe 14 that collects natural gas (NG), which is LNG vaporized in each vaporization pipe block 11, and a seawater supply that supplies seawater to the upper part of the vaporization pipe panel 16 so as to flow down along the surface of each vaporization pipe panel 16. Part (liquid supply part) 30. In addition, the number of the vaporization pipe blocks 11 provided in the vaporizer 10 is not limited to plural, and may be one.

  Each vaporizing pipe block 11 includes a plurality of (in this embodiment, five) vaporizing pipe panels 16, a supply side manifold 17 that distributes LNG from the distribution pipe 12 to each vaporizing pipe panel 16, and each vaporizing pipe panel 16. And a delivery-side manifold 19 that collects vaporized LNG (that is, NG) and sends it to the collecting pipe 14. The number of vaporization tube panels 16 included in one vaporization tube block 11 is not limited to five, and may be another number.

  Each vaporization tube panel 16 includes a plurality of (90 heat transfer tubes) vaporization tubes (heat transfer tubes) 21 arranged in parallel with each other on a vertical plane, and LNG from the supply-side manifold 17. A supply side header 22 that distributes the LNG, a heat transfer suppression unit 23 provided at both ends of the supply side header 22, a sending side header 24 that collects LNG vaporized in each vaporizing pipe 21 and sends it to the sending side manifold 19. , Respectively. The number of vaporization tubes included in one vaporization tube panel 16 is not limited to 90, and may be other numbers.

  Each vaporization tube 21 is a tube formed of a metal material having a high thermal conductivity such as aluminum or an aluminum alloy and extending in the vertical direction.

  The supply-side header 22 is a tube that extends in the horizontal direction along the vertical plane in which the vaporization tubes 21 are arranged. The supply side header 22 is also formed of a metal material having a high thermal conductivity such as aluminum or an aluminum alloy, like the vaporization tube 21. The supply-side header 22 is connected to the lower end portion of each vaporization tube 21 included in one vaporization tube panel 16. In addition, one end of the supply side header 22 is connected to the supply side manifold 17 so that LNG is supplied from the supply side manifold 17 via the header inner pipe 50 disposed therein.

  The header inner pipe 50 is a tubular member extending along the supply side header 22 and is disposed inside the supply side header 22 so as to be coaxial with the supply side header 22 (see FIG. 3). The header inner pipe 50 has an outer diameter smaller than the inner diameter of the supply-side header 22, so that when arranged inside the supply-side header 22, the outer circumferential surface of the header inner pipe 50 and the supply-side header 22 A predetermined space is formed between the inner peripheral surface. The header inner pipe 50 is connected to the supply-side manifold 17 so that LNG is supplied into the header inner pipe 50, and at a position corresponding to each vaporization pipe 21 on the pipe wall (peripheral wall) in the axial direction of the header inner pipe 50. Each has a hole 51. A plurality of (four holes in the present embodiment) are provided at positions corresponding to the respective vaporization tubes in the axial direction. Specifically, the plurality of holes 51 are arranged in the circumferential direction of the header inner pipe 50 at positions corresponding to the vaporizing pipes 21 in the axial direction (positions below the vaporizing pipes 21 in the present embodiment). Specifically, the holes 51 are arranged in the circumferential direction so that the centers of the holes 51 are located in the lower half of the header inner pipe 50.

  In this way, the header inner pipe 50 is provided inside the supply side header 22 to form a double pipe structure, and a plurality of holes 51 are provided at positions corresponding to the vaporization pipes 21 of the header inner pipe 50 to thereby provide each vaporization. The flow rate of LNG distributed to the pipe 21 is equalized.

  Further, by providing a plurality of holes 51 at positions corresponding to the vaporization tubes 21 of the header inner tube 50, the flow of LNG flowing into the vaporization tubes 21 becomes uniform. That is, LNG that has flowed out from the plurality of holes 51 at positions corresponding to the respective vaporization tubes 21 passes between the supply side header 22 and the header inner tube 50 toward the vaporization tube 21 and toward the upper side in the circumferential direction of the supply side header 22. By flowing into the vaporization tube 21 after flowing, LNG flows into the vaporization tube 21 immediately after flowing out of a hole provided in the upper portion of the header inner tube (for example, a position facing the lower end of the vaporization tube 21). Compared with the case, the flow of LNG becomes uniform.

  The heat transfer suppression unit 23 suppresses the heat transfer amount per unit area from the seawater in the supply side header 22. Specifically, the heat transfer suppression unit 23 is configured to transfer the heat of the seawater supplied from the seawater supply unit 30 to the second region A2 in the entire second region A2 of the supply header 22 (entire). Reduce the amount of heat transfer per unit area. Here, the second area A2 of the supply-side header 22 is an area outside the area (first area) A1 in which the plurality of vaporization tubes 21 are arranged in the longitudinal direction (horizontal direction) of the supply-side header 22. (See FIGS. 3 and 4). Specifically, the first region A <b> 1 is a region where the vaporizing tube 21 is disposed in the longitudinal direction of the supply-side header 22. That is, in the longitudinal direction, a region from the vaporizing tube 21 at one end to the vaporizing tube 21 at the other end of the plurality of vaporizing tubes 21 arranged along the supply-side header 22. On the other hand, the second region A2 is a region outside the first region A1 in the longitudinal direction. Specifically, when the vaporizing tube block 11 is disposed in the room H (see FIG. 6), the second region A2 is a portion located indoors other than the first region A1 of the supply side header 22. . In this case, each vaporizing pipe block 11 is arranged such that the end of the supply side header 22 opposite to the supply side manifold 17 is located in the room H.

  Specifically, the second region A2 includes the second region A2 on the supply side manifold 17 side (left side in FIG. 3) and the opposite side of the supply side manifold 17 (FIG. 3) across the first region A1 in the longitudinal direction. And the second region A2 on the right side of FIG. The second region A2 on the opposite side is a region from the outside of the vaporizing tube 21 arranged at the right end of the plurality of vaporizing tubes 21 in FIG. 4 to the right end of the supply-side header 22. Further, the second region A2 on the supply side manifold 17 side is a partition of the room H in which the vaporizing pipe block 11 is arranged from the outside of the vaporizing pipe 21 arranged at the left end of the plurality of vaporizing pipes 21 in FIG. This is the area up to the wall H1 (see FIGS. 1, 3, and 6).

  The heat transfer suppression unit 23 of the present embodiment is a heat insulating member that surrounds the second region A <b> 2 of the supply side header 22. The heat conductivity of the heat insulating member 23 is smaller than the heat conductivity of the supply side header 22 (specifically, the tube wall of the supply side header 22). Specifically, the heat insulating member 23 is formed by winding a tape made of foamed plastic such as urethane foam around the supply side header 22 so as to cover the surface of the second region A2 of the supply side header 22. The tape has a predetermined elasticity. The heat insulating member 23 is wound around the entire area of the second region A2 of the supply side header 22 until the thickness from the surface (outer peripheral surface) in the second region A2 of the supply side header 22 becomes 1.5 mm, for example. It is formed by overlapping. Note that the thickness of the heat insulating member 23 is based on the temperature difference between the seawater flowing toward the first region A1 of the supply side header 22 and the seawater flowing toward the second region A2, the thermal conductivity of the heat insulating member, and the like. Is set as appropriate.

  The heat insulating member 23 is provided only in the second region A2 in the supply side header 22 and is not provided in the first region A1. That is, the first area A1 of the supply side header 22 is exposed to the outside, and the second area A2 is covered with the heat insulating member 23 in the entire area.

  By providing such a heat insulating member 23 in the second region A2 of the supply-side header 22, heat transfer from seawater (specifically, seawater supplied from the seawater supply unit 30) in the first region A1 of the supply-side header 22 is performed. Compared to the rate, the heat transfer rate from the seawater in the second region A2 of the supply-side header 22 can be suppressed. Thereby, even if the temperature of the seawater which flows down toward the 2nd field is higher than the temperature of the seawater which flows down toward the 1st field A1 of supply side header 22 from seawater supply part 30, the 1st of supply side header 22 It is possible to prevent the temperature of the tube wall in the second region A2 from becoming higher than the temperature of the tube wall in the region A1.

  Moreover, since the heat insulation member 23 is formed with the tape which has the said elasticity, it has predetermined elasticity. Therefore, even if the supply-side header 22 is thermally contracted, the heat insulating member 23 itself is expanded and contracted along with the thermal contraction, and thereby, the heat-shrinkage of the supply-side header 22 (particularly, the thermal expansion and contraction in the radial direction of the supply-side header 22). It is possible to effectively prevent damage such as tearing of the heat insulating member 23 caused by

  The delivery side header 24 is a pipe extending in parallel with the supply side header 22. The delivery side header 24 is connected to the upper end portion of each vaporization tube 21 included in one vaporization tube panel 16 and the delivery side manifold 19.

  The plurality of vaporizing tube panels 16 configured as described above are arranged in a direction (left-right direction in FIG. 2) orthogonal to the panel surface (the vertical surface on which the vaporizing tubes 21 are arranged) in a mutually parallel posture.

  The supply-side manifold 17 is a pipe extending in a direction intersecting with the supply-side header 22 (in the present embodiment, a direction substantially orthogonal to the sheet: a direction orthogonal to the paper surface in FIG. 3), and is included in one vaporization tube block 11. Connected to the supply side header 22 and the distribution pipe 12.

  The delivery-side manifold 19 is a pipe extending in a direction intersecting with the delivery-side header 24 (in the present embodiment, a direction substantially orthogonal to the paper: a direction orthogonal to the paper surface in FIG. 3), and is included in one vaporization tube block 11. Connected to the sending side header 24 and the collecting pipe 14.

  The distribution pipe 12 is a pipe extending substantially parallel to the supply side manifold 17 and is connected to each supply side manifold 17. Further, the distribution pipe 12 is provided with a supply side connection portion 12a for connecting a pipe P1 for supplying LNG to the vaporizer 10 from the outside.

  The collecting pipe 14 is a pipe extending substantially in parallel with the delivery side manifold 19 and is connected to each delivery side manifold 19. Further, the collecting pipe 14 is provided with a sending side connection portion 14a for connecting a pipe P2 for sending NG to the outside such as a consumption area.

  The seawater supply unit 30 includes a trough 31 disposed in the vicinity of the upper end of each vaporization tube panel 16, a seawater header 32 that supplies seawater to each trough 31, a seawater manifold 33 that distributes seawater to each seawater header 32, (See FIGS. 5A and 5B). The trough 31 supplies seawater to the upper end portion of each vaporization tube panel 16 so that the seawater flows down along the surface of the vaporization tube panel 16 (specifically, each vaporization tube 21 constituting the vaporization tube panel 16). The seawater supplied from the trough 31 and flowing down the surface of the vaporization tube panel 16 and the LNG flowing in the vaporization tubes 21 exchange heat through the tube walls of the vaporization tubes 21, whereby LNG is vaporized and NG. It becomes.

  Each vaporization pipe block 11 of the vaporization apparatus 10 configured as described above is arranged in a room H surrounded by a wall of concrete or the like, as shown in FIG. Specifically, each vaporizing pipe block 11 is arranged in the room H such that the supply side manifold 17 and the delivery side manifold 19 in the vaporizing pipe block 11 are located outside the room H. This room H has a partition H1 that partitions the inside of the room and the outside of the room on the supply side header 22 while leaving the supply side header 22 and the delivery side header 24 between the vaporization pipe 21 and the supply side manifold 17. That is, a portion between the end of the supply-side header 22 (the end on the supply-side manifold 17 side) and the vaporizing tube 21 located on the end side passes through the partition wall H1 and also in the delivery-side header 24. A portion between the end (the end on the delivery side manifold 19 side) and the vaporizing tube 21 located on the end passes through the partition wall H1. Each pipe 12, 14, 17, 19 disposed outside the room H is provided with a heat insulating member so as to cover the entire surface.

  The vaporizer 10 configured as described above vaporizes LNG as follows.

  Seawater is supplied from the trough 31 to the surface of each vaporization tube panel 16, and LNG is supplied to the distribution pipe 12 from a supply pump or the like through the pipe P1 connected to the supply side connection portion 12a. The distribution pipe 12 distributes LNG supplied by a supply pump or the like to each supply side manifold 17 connected to the distribution pipe 12, and each supply side manifold 17 supplies the LNG from the distribution pipe 12 to the supply side manifold 17. Are distributed to each supply-side header 22 connected to the. Each supply-side header 22 distributes the supplied LNG to each vaporization tube 21 connected to the supply-side header 22. In each vaporization tube 21, the LNG supplied from the supply-side header 22 flows through the vaporization tube 21 from the lower end to the upper end. At this time, the LNG flowing inside the vaporizing tube 21 exchanges heat with the seawater flowing down the surface of the vaporizing tube 21 through the tube wall of the vaporizing tube 21. By this heat exchange, LNG vaporizes and becomes NG.

  When LNG is vaporized in the vaporizer 10, the seawater supply unit 30 is not only in the region where the vaporization tube 21 of the vaporization tube panel 16 is provided, but also in its width direction (vaporization in the vaporization tube panel 16. Seawater is also supplied to the region outside the direction in which the tubes 21 are arranged. This is because the vaporization pipes 21 located at both ends in the width direction are sufficiently brought into contact with seawater on the entire circumference. Thereby, when the LNG is vaporized into NG, that is, during the operation of the vaporizer 10, the seawater flowing down toward the first region A1 of the supply side header 22 along the vaporization tube panel 16 is vaporized. The temperature is sufficiently low when it flows down to the position of the supply side header 22 due to heat exchange with the LNG inside, but it flows down outside the vaporization pipe (that is, into the second region A2 of the supply side header 22). Since the seawater flows down with little heat exchange with the LNG in the vaporization pipe 21, the temperature when the seawater reaches the position of the supply-side header 22 compared to the seawater that flows toward the first region A1. Is expensive. Therefore, if the heat insulating member (heat transfer suppressing portion) 23 is not provided in the second region A2 of the supply side header 22, the heat exchange with the seawater is performed more than the tube wall of the first region A1 of the supply side header 22. The tube wall of the second region A2 has a higher temperature, and the LNG (inner header tube 50) supplied to the vaporization tube 21 adjacent to the second region A2 (the vaporization tube 21 at the end portion in the width direction of the vaporization tube panel). LNG) flowing out from the hole 51 and flowing between the header inner pipe 50 and the supply side header 22 toward the vaporization pipe 21 toward the upper side in the circumferential direction of the supply side header 22) is located at the central position of the first region A1. The temperature is higher than LNG supplied to the vaporizing tube 21. However, in the vaporization apparatus 10 of the present embodiment, since the heat insulating member 23 is provided in the second region A2 of the supply side header 22, the unit area from the seawater having a high temperature in the pipe wall of the second region A2 is provided. The amount of heat transfer per unit is suppressed, and as a result, LNG supplied to the vaporization pipe 21 adjacent to the second area A2 of the supply side header 22 and LNG supplied to the vaporization pipe 21 at the center position of the first area A1. It is possible to prevent a temperature difference between the two.

  LNG vaporized in each vaporization tube 21, that is, NG is collected by the delivery side header 24 and delivered to the delivery side manifold 19. The NG sent to the delivery side manifold 19 is sent to the consumption area or the like through the collecting pipe 14 and the pipe P2 connected to the delivery side connection portion 14a.

  According to the above vaporizer 10, even if the temperature of the seawater flowing toward the second region A2 is higher than the seawater flowing toward the first region A1 of the supply side header 22, the heat insulating member (heat transfer suppression unit) 23, transmission per unit area from seawater in the entire second area A2 of the supply-side header 22 (area other than the first area A1 of the supply-side header 22 in the room H in which each vaporizing pipe block 11 is accommodated). The amount of heat is suppressed. Therefore, it becomes possible to prevent the second region A2 from becoming hotter than the first region A1 of the supply-side header 22 by the seawater having different temperatures. Thereby, the temperature difference between the LNG distributed to the vaporizing tube 21 at the end position in the horizontal direction (width direction) of the vaporizing tube panel 16 and the LNG distributed to the vaporizing tube 21 at the central position is suppressed. The bending of the supply-side header 22 due to the amount of thermal expansion and contraction of each vaporizing tube 21 is prevented.

  Moreover, in the vaporization apparatus 10 of this embodiment, the whole area (the whole) of 2nd area | region A2 of the supply side header 22 is enclosed by the heat insulation member 23, The unit area from the seawater in 1st area | region A1 of the supply side header 22 Compared to the heat transfer amount, the heat transfer amount per unit area from seawater in the second region A2 of the supply-side header 22 can be easily and reliably suppressed.

  Moreover, in the vaporization apparatus 10 of this embodiment, since the heat insulation member 23 has predetermined elasticity, damage to the heat insulation member 23 due to thermal expansion and contraction of the supply side header 22 can be prevented. Specifically, the supply-side header 22 thermally expands and contracts due to a temperature difference between the operation of the vaporizer 10 and when the vaporizer 10 is stopped, but the heat insulating member 23 surrounding the supply-side header 22 has a predetermined stretchability. By expanding and contracting, it expands and contracts in accordance with the thermal expansion and contraction of the supply side header 22. Thereby, the damage of the heat insulation member 23 resulting from the thermal expansion / contraction (especially radial thermal expansion / contraction) of the supply side header 22 can be prevented effectively.

  In order to confirm the effect of the heat insulating member, the LNG flowing in the second region of the supply side header 22 during operation of the vaporizer is used by using the vaporizer having the same configuration except the vaporizer 10 and the heat insulator 23 of the above embodiment. The temperature of was examined.

  The supply-side header of this vaporizer is made of aluminum having an outer shape of 165.2 mm and has a heat transfer coefficient of 5000 W / mK. The heat conductivity of the heat insulating member is 1 W / mK.

  Each state of supplying 145 ° C. LNG to this supply-side header, having no heat insulation member, having a heat insulation member having a thickness of 0.5 mm, and having a heat insulation member having a thickness of 1.5 mm The temperature of LNG flowing through the second region of the supply-side header was measured. The result is shown in FIG.

  As can be seen from this figure, the temperature rise due to seawater of LNG flowing through the inside by providing the heat insulating member in the second region of the supply-side header, even if it is a thin heat insulating member, compared to the state in which the heat insulating member is not provided. Was confirmed to be suppressed.

  Thereby, even if the temperature of the seawater that flows down toward the second region is higher than the temperature of the seawater that flows down toward the first region, by providing the heat insulating member in the second region, It was confirmed that it was possible to suppress the temperature difference between the two regions.

  In addition, the low temperature liquefied gas vaporization apparatus of this invention is not limited to the said embodiment, Of course, in the range which does not deviate from the summary of this invention, a various change can be added.

  The specific configuration of the heat insulating member 23 is not limited. For example, the heat insulating member 23 of the above embodiment is configured by winding (wrapping) a tape made of foamed plastic such as urethane foam around the second region A2 of the supply side header 22, but is not limited thereto. That is, as shown in FIG. 8, the heat insulating member has a cylindrical or formed shape made of a material having a low thermal conductivity such as a resin such as silicon or polyvinyl chloride, a foamed resin, a resin woven with glass fiber, or rubber. The bottom cylindrical members 23A and 23B may be used. The cylindrical heat insulating member 23A and the bottomed cylindrical heat insulating member 23B have a diameter (inner diameter) corresponding to the diameter (outer diameter) of the outer peripheral surface of the second region A2 of the supply side header 22 or the outer diameter. Each of the inner peripheral surfaces 123 has a large inner diameter. The heat insulating members 23A and 23B are covered with a cylindrical heat insulating member 23A around the second region A2 on the supply side manifold 17 side of the supply side header 22, and the bottomed cylindrical heat insulation member 23B is provided on the supply side header. 22 is covered with the second region A2 on the opposite side of the supply side manifold 17. Thereby, the whole area of 2nd field A2 is surrounded by heat insulation members 23A and 23B.

  The heat insulating member may be formed by spraying foamed plastic such as urethane foam on the surface of the second region A2 of the supply-side header 22 until a predetermined thickness is reached.

  Further, the heat transfer suppression unit is not limited to the configuration surrounding the second region A2 of the supply side header 22. For example, it may be a cover member 60 (see FIG. 9) that is disposed above the second region A2 of the supply-side header 22 and has a shape that covers the second region A2 of the supply-side header 22 in plan view. Specifically, the cover member 60 has a width (horizontal width) larger than the outer diameter of the supply header 22 so as to cover the second region A2 of the supply header 22 in plan view. And this cover member 60 is arrange | positioned in the 2nd area | region A2 above the 2nd area | region A2 of the supply side header 22 at intervals (or so that it may contact). According to such a configuration, the seawater that flows down outside the vaporization tube at the end position in the longitudinal direction (horizontal direction) of the supply header and hardly exchanges heat with LNG flowing in the vaporization tube, It is possible to prevent hitting the second region of the supply header. Thereby, even if the temperature of the seawater flowing toward the second area is higher than the seawater flowing toward the first area of the supply-side header, the temperature between the first area and the second area of the pipe between the vaporization pipes is higher. It is possible to prevent the difference in temperature from occurring. That is, by providing the cover member 60 so that the seawater flowing down from the seawater supply unit 30 does not hit the second area A2 of the supply-side header 22, the heat from the seawater in the second area A2 of the supply-side header 22 is provided. Thus, the temperature difference of LNG flowing in the first region A1 and the second region A2 of the supply side header 22 may be suppressed.

  Further, the tube wall of the second region A2 of the supply side header may be made of a material having a smaller thermal conductivity than the tube wall of the first region A1. Specifically, for example, the tube wall of the first region A1 is formed of a metal having high thermal conductivity such as aluminum or an aluminum alloy as in the first embodiment, and the tube wall of the second region A2 is made of iron or SUS. Form. As a result, the thermal conductivity of the tube wall is smaller in the second region A2 than in the first region A1 of the supply-side header, and seawater having a higher temperature than the first region A1 in the supply-side header is in the second region A2. In this case, it is possible to prevent a temperature difference from occurring between the temperature of the LNG flowing inside the first area A1 of the supply side header and the temperature of the LNG flowing inside the second area A2. As a result, it is possible to prevent the supply-side header from being bent due to this temperature difference.

  In addition, by configuring only the tube wall of the second region A2 of the supply side header 22 in a layered manner in the thickness direction of the tube wall, the second region from the surface (outer peripheral surface) of the second region A2 of the supply side header. By suppressing the thermal conductivity to the inside of A2 (inner peripheral surface of the supply-side header), the thermal conductivity (equivalent thermal conductivity) of the tube wall of the second region A2 of the supply-side header 22 is reduced to that of the first region A1. It may be smaller than the thermal conductivity of the tube wall. Specifically, as shown in FIG. 10, the tube wall in the second region A2 of the supply side header 22 is composed of a plurality of layers (two layers in the example of FIG. 10), and air or a heat insulating member is provided between the layers. The heat conduction suppressing layer 62 filled with is formed. Even with such a configuration, the thermal conductivity (equivalent thermal conductivity) in the tube wall of the second region A2 of the supply side header 22 becomes smaller than the thermal conductivity in the tube wall of the first region A1. Note that the number of layers constituting the tube wall may be three or more.

  Moreover, in the said embodiment, although the header inner pipe | tube 50 is provided in the inside of the supply side header 22, it is not limited to this structure. In other words, the LNG may be directly supplied from the supply side manifold 17 to the supply side header 22 without providing the header inner pipe 50.

DESCRIPTION OF SYMBOLS 10 Low-temperature liquefied gas vaporizer 11 Evaporation pipe block 12 Distribution pipe 14 Collecting pipe 16 Evaporation pipe panel 17 Supply side manifold 19 Delivery side manifold 21 Evaporation pipe 22 Supply side header (distribution pipe between vaporization pipes)
23 Heat transfer suppression part (heat insulation member)
24 Delivery side header 30 Seawater supply part (liquid supply part)
50 Header inner pipe 51 Hole A1 First area A2 of supply-side header Second area of supply-side header

Claims (6)

An apparatus for vaporizing a low-temperature liquefied gas,
There are a plurality of vaporization tubes for evaporating the low-temperature liquefied gas flowing in the vertical direction and flowing inside by heat exchange with the outside, and an inter-vaporization pipe distribution pipe for distributing the low-temperature liquefied gas to each of the vaporization tubes. And a plurality of vaporization tubes arranged in a horizontal direction on a vertical plane, and the vaporization pipe distribution pipe extends in the horizontal direction and is connected to a lower end portion of each vaporization pipe, and
A liquid supply section for supplying a heat exchange liquid from an upper end of the vaporization tube panel so as to flow down along the plurality of vaporization tubes;
Compared to the temperature of the heat exchange liquid flowing down toward the first region of the inter-vaporization tube distribution pipe in which the plurality of vaporization tubes are arranged, the space between the vaporization tubes outside the first region in the horizontal direction even if better temperature higher heat exchange fluid flows down towards the second region of the distribution pipe, in comparison with the amount of heat transfer per unit area from the heat transfer fluid that Tsutawa to the first region, before SL vaporizer of low-temperature liquefied gas and a heat transfer suppressing portion REDUCE below comparable amount of heat transfer per unit area of the heat transfer fluid that Tsutawa the second region. The heat transfer suppression unit is a heat insulating member that surrounds a second region of the inter-vaporization pipe distribution pipe,
The low-temperature liquefied gas vaporizer according to claim 1, wherein a thermal conductivity of the heat insulating member is smaller than a thermal conductivity of the inter-vaporization pipe distribution pipe.   The low-temperature liquefied gas vaporizer according to claim 2, wherein the heat insulating member has a predetermined elasticity.   2. The low temperature according to claim 1, wherein the heat transfer suppression unit is a cover member that is disposed above the second region of the inter-vaporization pipe distribution pipe and has a shape that covers the second area of the distribution pipe in a plan view. Liquefied gas vaporizer. The portion between the end of the inter-vaporization pipe distribution pipe and the vaporization pipe located on the end side passes through the partition wall,
The low-temperature liquefied gas vaporizer according to any one of claims 1 to 4, wherein the second region is a region from the partition wall to a vaporization tube located on the end side. An apparatus for vaporizing a low-temperature liquefied gas,
There are a plurality of vaporization tubes for evaporating the low-temperature liquefied gas flowing in the vertical direction and flowing inside by heat exchange with the outside, and an inter-vaporization pipe distribution pipe for distributing the low-temperature liquefied gas to each of the vaporization tubes. And a plurality of vaporization tubes arranged in a horizontal direction on a specific vertical plane, and the vaporization pipe distribution pipes extending in the horizontal direction and connected to the lower ends of the vaporization pipes, respectively,
A liquid supply unit for supplying a heat exchange liquid from an upper end of the vaporization tube panel so as to flow down along the plurality of vaporization tubes,
The tube wall in the second region of the inter-vaporization tube distribution pipe outside the first region in the horizontal direction, rather than the tube wall in the first region of the inter-vaporization tube distribution tube in which the plurality of vaporization tubes are arranged. Is a low-temperature liquefied gas vaporizer with lower thermal conductivity.

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