JP2015183861A - Normal-temperature water type vaporizer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase over a wide range, a flow velocity of normal-temperature water in a lower region in a normal-temperature water type vaporizer which vaporize liquefied gas flowing from a lower side to an upper side by indirectly contacting the liquefied gas with normal-temperature water .SOLUTION: There is provided a normal-temperature water type vaporizer 100 that comprises: a transversely installed cylindrical body container 1 into which normal-temperature water is supplied; a heat transfer tube bundles 2 which are arranged in an axial direction of the body container 1 and within the body container 1 and in which liquefied gas flows from a lower part to an upper part; normal-temperature water guide plates 5 arranged within the body container 1 and at both sides of the heat transfer tube bundles 2 as seen from an axial direction of the body container 1; a normal-temperature water supply pipe 3 for supplying normal-temperature water from lower part of the heat transfer tube bundles 2 into the body container 1; and heat-removed water discharging pipe 4 for discharging water from which heat is removed through heat exchanging with liquefied gas within the heat transfer tube bundles 2 from the upper part of the heat transfer tube bundle 2 to the outside of the body container. The normal-temperature water guide plates 5 are provided with slant segments 14 that are narrowed inward as they come close to the upside as seen from an axial direction of the body container 1.

Description

  The present invention relates to a room temperature water vaporizer that vaporizes a liquefied gas such as LNG with heat of room temperature water.

  As a fluid vaporizer that vaporizes a liquefied gas such as LNG (liquefied natural gas) with the heat of the fluid, there is one described in Patent Document 1, for example. The normal temperature water vaporizer described in Patent Document 1 vaporizes the liquefied gas in the heat transfer tube bundle by bringing the normal temperature water into contact with the heat transfer tube bundle in which the liquefied gas flows upward from below. By using room temperature water as a heat source fluid, liquefied gas can be vaporized even in a place where hot water cannot be easily secured.

  Here, in the room temperature water vaporizer of Patent Document 1, the room temperature water guide plates are provided on both sides of the heat transfer tube bundle in order to suppress freezing of room temperature water on the surface of the heat transfer tube in the lower region where the low temperature liquefied gas is introduced. Is provided, and the interval between the guide plates is configured to be narrower in the lower region. By doing so, in the lower region where the distance between the guide plates is narrow, the flow rate of the normal temperature water flowing between the guide plates is increased, and freezing of the normal temperature water in the lower region can be suppressed.

JP2013-155912A

  However, in the room temperature water vaporizer of Patent Document 1, although the flow rate of room temperature water is certainly large in the lower region, room temperature water having a large flow rate tends to flow directly to the upper region along the guide plate. (See FIG. 3 of Patent Document 1). That is, it cannot be said that room temperature water having a large flow velocity can be effectively utilized in the lower region, and there is room for improvement in this respect.

  The present invention has been made in view of the above circumstances, and in a room temperature water vaporizer that vaporizes a liquefied gas flowing upward from below by indirect contact with room temperature water, the flow rate of room temperature water in the lower region is The purpose is to increase the temperature over a wide range and more effectively suppress freezing of room temperature water.

  The present invention is a room temperature water vaporizer that vaporizes the liquefied gas by indirect contact between the liquefied gas and the normal temperature water, and is disposed horizontally, and a cylindrical main body container that is supplied with the normal temperature water inside, A heat transfer tube bundle that is arranged inside the main body container along the axial direction of the main body container and in which liquefied gas flows from below to above, and the inside of the main body container and the heat transfer tube when viewed from the axial direction of the main body container. Heat exchange between room temperature water guide plates arranged on both sides of the heat tube bundle, a room temperature water supply pipe for supplying room temperature water to the inside of the main body container from below the heat transfer tube bundle, and a liquefied gas in the heat transfer tube bundle A heat-extracted water discharge pipe for discharging the water removed by heat from above the heat transfer tube bundle to the outside of the main body container, and the upper portion of the room temperature water guide plate as viewed from the axial direction of the main body container. It is characterized by an inclined part that narrows toward the inside as it goes to That.

  According to the room temperature water vaporizer of the present invention, when the room temperature water supplied from the room temperature water supply pipe is directed to the upper heat removal water discharge pipe, a part of the room temperature water is bounced off at the inclined portion and flows downward. A reverse flow is formed. For this reason, the flow rate of room temperature water in the lower region is increased over a wide range, and freezing of room temperature water can be more effectively suppressed.

It is sectional drawing along the axial direction which shows a normal temperature water vaporizer. It is AA sectional drawing of FIG. It is a figure which shows the result of having analyzed the flow velocity distribution of the normal temperature water in a main body container numerically.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In the following embodiments, the liquefied gas to be vaporized is LNG, but the vaporization target is not limited to LNG.

(Configuration of room temperature water vaporizer)
As shown in FIG. 1, the room temperature water vaporizer 100 includes a main body container 1, a heat transfer tube bundle 2, a room temperature water supply pipe 3, a hot water discharge pipe 4, and the like. The room-temperature water vaporizer 100 is a room-temperature water-type vaporizer that vaporizes LNG by indirectly contacting LNG and room-temperature water. Here, the room temperature water refers to water at room temperature, and refers to water at a natural temperature that does not heat or cool, for example, about 15 to 35 ° C.

(Main body container)
The main body container 1 is a cylindrical container into which normal temperature water is supplied, and is placed horizontally (installed so that the axial direction of the main body container 1 is horizontal). Both ends of the main body container 1 are closed by lid plates 22. The main body container 1 is supported by leg members 8.

(Heat transfer tube bundle)
Inside the main body container 1, a heat transfer tube bundle 2 through which LNG flows is disposed. The heat transfer tube bundle 2 is a bundle of heat transfer tubes including a large number of heat transfer tubes 11 and a number of 180 ° return bends 12 (hereinafter referred to as return bends 12) that connect the heat transfer tubes 11 to each other. The LNG is caused to flow through the heat transfer tube bundle 2 from below to above.

  The heat transfer tube 11 is a straight tube and is disposed along the axial direction of the main body container 1. By connecting the heat transfer tubes 11 with a return bend 12, the heat transfer tubes 11 are folded back 180 ° a plurality of times along the axial direction of the main body container 1. The return bend 12 is arranged to include an oblique direction.

  Here, the upstream end of the heat transfer tube bundle 2 is connected to the LNG distribution pipe 20, and the downstream end of the heat transfer tube bundle 2 is connected to the vaporized gas merging pipe 21. The LNG distribution pipe 20 is a pipe for distributing and supplying the LNG supplied from the LNG receiving pipe 6 to the heat transfer pipe bundle 2, and is connected to the LNG receiving pipe 6. In the present embodiment, LNG supplied from the LNG receiving pipe 6 is caused to flow through the heat transfer tube bundle 2 through three paths (three paths). The vaporized gas merging pipe 21 is a pipe for collecting vaporized gas (NG) vaporized by flowing in the heat transfer tube bundle 2 through a plurality of paths (multiple paths), and is connected to the vaporized gas outlet pipe 7. Yes. In the present embodiment, the vaporized gas that has flowed through the heat transfer tube bundle 2 through three paths and vaporized is combined into one by the vaporized gas junction tube 21.

  As shown in FIG. 2, there are a plurality of LNG paths flowing through the heat transfer tube bundle 2, and in this embodiment, there are three paths (three paths). In each of these three paths (three paths), seven return bends 12 are provided in the present embodiment. That is, each of the three paths (three paths) in the heat transfer tube bundle 2 is formed by folding the heat transfer tubes 11 seven times, and in this embodiment, there are eight straight pipe portions (eight stages). ing. Note that the number of paths, the number of stages, and the like are not limited to those of the present embodiment.

(Normal temperature water supply pipe)
The room temperature water supply pipe 3 is a pipe for supplying room temperature water into the main body container 1 from below the heat transfer tube bundle 2. The room temperature water supply pipe 3 includes a room temperature water supply header pipe 16 (mother pipe) attached to the lower side surface of the main body container 1 in a horizontally arranged state, and a plurality of branch pipes from the room temperature water supply header pipe 16 ( In this embodiment, two normal temperature moisture pipes 17 (branch pipes) are provided.

  The room temperature moisture pipe 17 is piped along the axial direction of the main body container 1 inside the main body container 1 and in the vicinity of the bottom thereof. The room temperature moisture pipe 17 is piped below the heat transfer tube bundle 2 (lowermost heat transfer tube 11) over the entire length of the heat transfer tube bundle 2 (heat transfer tube 11).

  Here, the room temperature moisture pipe 17 is provided with a plurality of holes 17a (17b) for supplying room temperature water into the main body container 1 at predetermined intervals. As shown in FIG. 2, the plurality of holes 17 a (17 b) are opened so that room temperature water blows obliquely upward as viewed from the axial direction of the main body container 1. In the present embodiment, the position of the hole 17a (17b) is inclined by 30 ° from the vertical direction, and the normal temperature water discharged from the hole 17a is the inclined portion 14 of the normal temperature water guide plate 5 described later. Configured to head towards. In addition, the holes 17 a and 17 b are symmetrical positions when viewed from the axial direction of the main body container 1.

(Heat removal water discharge pipe)
The heat removal water discharge pipe 4 is a body container for water obtained by removing normal temperature water from LNG and room temperature water through indirect contact with the heat transfer pipe 11 (water removed by heat exchange with LNG). 1 is a tube for discharging to the outside. In addition, after returning the low temperature water discharged | emitted outside the main body container 1 to normal temperature, it returns to the normal temperature water supply pipe 3 (normal temperature water supply header pipe | tube 16), and circulates and uses it as normal temperature water which vaporizes LNG. It is preferable. As a method of returning the low temperature water discharged to the outside of the main body container 1 to room temperature, for example, the discharged low temperature water is once received in a tank of a predetermined capacity and returned to the normal temperature water supply header pipe 16. There is a method of naturally raising the temperature to room temperature.

  The heat removal water discharge pipe 4 is branched from the heat removal water discharge header pipe 18 (mother pipe) attached to the upper side surface of the main body container 1 in a horizontally disposed state, and the heat removal water discharge header pipe 18. And a plurality of (two in this embodiment) heat removal water collecting pipes 19 (branch pipes).

  The hot water collecting pipe 19 is piped along the axial direction of the main body container 1 inside the main body container 1 and in the vicinity of the ceiling portion thereof. Further, the heat removal water collecting pipe 19 is piped above the heat transfer pipe bundle 2 (uppermost heat transfer pipe 11) over the entire length of the heat transfer pipe bundle 2 (heat transfer pipe 11).

  Here, a plurality of holes 19a (19b) are formed in the heat removal water collecting pipe 19 at predetermined intervals for collecting the heat removed. As shown in FIG. 2, the plurality of holes 19 a (19 b) are opened in the horizontal direction on the side surface of the hot water collecting pipe 19. Furthermore, a hole 19 a (19 b) is formed in the center of the side surface of the hot water collecting pipe 19 as viewed from the axial direction of the main body container 1. The hole 19a (19b) does not necessarily have to be opened in the horizontal direction. It is not always necessary that the hole 19a (19b) is located at the center of the side surface of the hot water collecting pipe 19.

(Room temperature water guide plate)
A pair of room-temperature water guide plates 5 (5a, 5b) are disposed symmetrically on both sides of the heat transfer tube bundle 2 inside the main body container 1 as viewed from the axial direction of the main body container 1. The room temperature water guide plate 5 (5a, 5b) is disposed along the axial direction of the main body container 1 over the entire length of the heat transfer tube bundle 2 (heat transfer tube 11).

  The plate material constituting the room temperature water guide plate 5 a (5 b) is disposed in the horizontally placed main body container 1, and is seen from the upper vertical portion 13 extending in the vertical direction and the axial direction of the main body container 1. The lower vertical portion 15 is disposed on the inner side of the upper vertical portion 13 and similarly extends in the vertical direction, and the inclined portion 14 extends from the lower end of the upper vertical portion 13 to the upper end of the lower vertical portion 15. That is, the inclined portion 14 has a shape that narrows inward as it goes upward as viewed from the axial direction of the main body container 1. The room temperature water guide plate 5a (5b) may be formed by bending a single plate material, or may be formed by joining a plurality of plate materials by welding or the like.

  In the following description, for the sake of convenience, the upper half region (the region between the upper vertical portion 13 and the upper portion of the inclined portion 14) of the region between the pair of room temperature water guide plates 5a and 5b is the upper region. The lower half region (the region between the lower vertical portion 15 and the lower portion of the inclined portion 14) is referred to as a lower region.

  In the present embodiment, the wide lower region is effectively used, and the number of times the heat transfer tube 11 is folded back is greater in the lower region than in the upper region. In other words, more return bends 12 are arranged in the lower region than in the upper region, and the number of stages of the heat transfer tubes 11 is increased in the lower region than in the upper region. Specifically, in the upper region, the number of straight pipe sections per path (one pass) is three, whereas in the lower area, the number of stages of the heat transfer tubes 11 per path (one pass) is five.

  Further, a guide member 9 is attached to the upper end portion of the room temperature water guide plate 5a (5b), and a guide member 10 is attached to the lower end portion thereof by welding or the like. On the other hand, a pair of left and right support members 23 are attached near the ceiling in the main body container 1, and a pair of left and right support members 24 are attached near the bottom by welding or the like. The guide member 9 is slidable with respect to the support member 23, and the guide member 10 is slidable with respect to the support member 24 in the axial direction of the main body container 1. The guide members 9 and 10 and the support members 23 and 24 are all made of angle steel (angle steel), but are not limited thereto. The heat removal water discharge pipe 4 (heat removal water collection pipe 19) is disposed between the pair of left and right support members 23, and the room temperature water supply pipe 3 (room temperature water pipe 17) is interposed between the pair of left and right support members 24. ) Is arranged.

  The room temperature water guide plate 5 and the heat transfer tube bundle 2 are fixed and integrated with each other by a steel material or the like. The LNG receiving pipe 6, the LNG distribution pipe 20, the vaporized gas junction pipe 21, the vaporized gas outlet pipe 7, the heat transfer pipe bundle 2, and the room temperature water guide plate 5 support the guide members 9 and 10 along the support members 23 and 24. While being slid with respect to the members 23 and 24, it can be extracted integrally from the main body container 1, and has a structure excellent in maintenance and management.

(Manufacture of LNG vaporized gas)
LNG is supplied from the inlet 6 a of the LNG receiving pipe 6 to the room temperature water vaporizer 100. The supplied LNG is distributed into three paths by the LNG distribution pipe 20, and flows through the heat transfer tube bundle 2 from below to above while meandering. On the other hand, normal temperature water is supplied from the inlet 16a of the normal temperature water supply header pipe 16 into the main body container 1 as a heat source fluid.

  The supplied room temperature water rises between the pair of room temperature water guide plates 5a and 5b. At this time, LNG is vaporized by the indirect contact between LNG and room temperature water via the heat transfer tube 11. The vaporized gas (NG) merges in the vaporized gas junction pipe 21 and then exits from the outlet 7 a of the vaporized gas outlet pipe 7. The water removed by indirect contact with LNG is collected by the heat removal water collecting pipe 19 and then comes out from the outlet 18 a of the heat removal water discharge header pipe 18.

  Of the region between the pair of room temperature water guide plates 5a and 5b where the heat transfer tube bundle 2 is disposed, the lower region is basically an evaporation region for mainly vaporizing LNG in a liquid state. On the other hand, basically, the upper region is mainly vaporized gas (or vaporized gas in which liquid LNG is mixed) so that the liquid LNG is mixed in the vaporized gas and does not leave the main body container 1. ) Is heated to completely vaporize LNG, that is, a heating region.

(Action / Effect)
In this embodiment, a pair of normal temperature water guide plates 5a and 5b are arranged on both sides of the heat transfer tube bundle 2 when viewed from the axial direction of the main body container 1, and the normal temperature water guide plates 5a (5b) An inclined portion 14 is formed which narrows toward the inside as it goes to the front. By providing such an inclined portion 14, when the normal temperature water supplied from the normal temperature water supply pipe 3 is directed to the upper hot water discharge pipe 4, a part of the normal temperature water is bounced back by the inclined portion 14. Form a reversal flow to For this reason, the flow rate of room temperature water in the lower region, which is the evaporation region of the liquefied gas, is increased and the high flow rate region can be maintained over a wide range, so that freezing of room temperature water can be more effectively suppressed. it can.

  Moreover, in this embodiment, the normal temperature water guide plate 5 is arrange | positioned over the full length of the heat exchanger tube bundle 2 along the axial direction of the main body container 1. FIG. For this reason, the flow rate of room temperature water in the lower region can be increased over the entire length of the heat transfer tube bundle 2, and freezing of room temperature water can be more reliably suppressed or prevented.

  Moreover, in this embodiment, the part below the inclination part 14 among the normal temperature water guide plates 5a (5b) is the lower vertical part 15 extending along the vertical direction. Here, in the lower region, which is the evaporation region of the liquefied gas, it is desirable to reduce the cross-sectional area as much as possible and increase the flow rate of room temperature water. On the other hand, if the cross-sectional area is too small, it is difficult to fold and dispose the heat transfer tubes 11 in the lower region, and the vaporization efficiency of the liquefied gas may be reduced. Therefore, as described above, by setting the lower portion of the inclined portion 14 as the lower vertical portion 15, the cross-sectional area of the lower region becomes appropriate, and the request and transmission of increasing the flow rate of room temperature water in the lower region are achieved. The demand for multi-stage arrangement of the heat tubes 11 can be realized in a balanced manner.

  Moreover, in this embodiment, the normal temperature water supplied from the normal temperature water supply pipe 3 (normal temperature moisture piping 17) is discharged toward the inclination part 14. FIG. For this reason, the normal temperature water supplied from the normal temperature water supply pipe 3 can be positively rebounded by the inclined portion 14, and a downward reversal flow is more easily formed. As a result, the flow rate of room temperature water in the lower region can be further increased over a wide range.

  In addition, on both sides of the room temperature water supply pipe 3 (room temperature moisture pipe 17) when viewed from the axial direction of the main body container 1, a function of an outflow suppression member that suppresses the outflow of room temperature water to the outside of the room temperature water guide plate 5 is provided. A supporting member 24 is provided. For this reason, the room temperature water supplied from the room temperature water supply pipe 3 can be more reliably directed to the area inside the room temperature water guide plate 5, that is, the area where the heat transfer tube bundle 2 is disposed. Can be used effectively without waste.

(Example)
FIG. 3 is a diagram showing the result of numerical analysis of the flow rate distribution of room temperature water in the main body container 1. The unit of the flow velocity is [m / s]. As can be seen from FIG. 3, the normal temperature water supplied from the normal temperature water supply pipe 3 (normal temperature moisture pipe 17) and going upward is rebounded by the inclined portion 14 to form a reversal flow and escapes to the upper region as it is. It is suppressed to go. For this reason, the flow rate of room temperature water in the lower region is large over a wide range.

  Here, the superficial velocity calculated by dividing the supply amount of room temperature water by the cross-sectional area of the lower region is about 0.006 [m / s]. On the other hand, in order to prevent freezing of room temperature water in the lower region, it is preferable that a flow rate of about 10 times or more the superficial velocity is generated around the heat transfer tube 11 in the lower region. In the present embodiment, a high flow velocity of approximately 0.06 [m / s] or more and 10 times or more of the superficial velocity is achieved around the heat transfer tube 11 in the lower region, and icing is effectively suppressed in the lower region. It was also shown from the results of numerical analysis that it was possible.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims. .

  For example, in the above embodiment, only one inclined portion 14 is provided on the room temperature water guide plate 5a (5b), but a plurality of inclined portions 14 may be provided on the room temperature water guide plate 5a (5b). In addition, the inclined portion 14 may be curved, for example, as long as it has a shape that narrows inward as it goes upward.

1: Main body container 2: Heat transfer tube bundle 3: Room temperature water supply tube 4: Heat extraction water discharge tube 5: Room temperature water guide plate 13: Upper vertical portion 14: Inclined portion 15: Lower vertical portion 24: Support member (outflow suppression) Element)
100: Room temperature water vaporizer

Claims (5)

A room temperature water vaporizer that vaporizes the liquefied gas by indirectly contacting the liquefied gas with normal temperature water,
A cylindrical body container that is placed horizontally and supplied with room temperature water inside,
A heat transfer tube bundle that is arranged inside the main body container along the axial direction of the main body container, and in which liquefied gas flows from below to above,
A room-temperature water guide plate disposed inside the main body container and on both sides of the heat transfer tube bundle, as viewed from the axial direction of the main body container,
A normal temperature water supply pipe for supplying normal temperature water into the main body container from below the heat transfer tube bundle;
A heat removal water discharge pipe for discharging water extracted by heat exchange with the liquefied gas in the heat transfer pipe bundle to the outside of the main body container from above the heat transfer pipe bundle;
With
The room temperature water guide plate is formed with an inclined portion that narrows inward as it goes upward as viewed from the axial direction of the main body container.   The normal temperature water guide plate is a normal temperature water vaporizer disposed along the axial direction of the main body container over the entire length of the heat transfer tube bundle.   The room-temperature water vaporizer according to claim 1 or 2, wherein a part of the room-temperature water guide plate that is lower than the inclined part is a vertical part extending along a vertical direction.   The normal temperature water vaporizer according to any one of claims 1 to 3, wherein the normal temperature water supplied from the normal temperature water supply pipe is discharged toward the inclined portion.   The outflow suppression member which suppresses that normal temperature water flows out to the outer side of the said normal temperature water guide plate is provided in the both sides of the said normal temperature water supply pipe seeing from the axial direction of the said main body container. The room temperature water vaporizer of any one of Claims.