JP2013185771A - Heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat exchanger capable of surely vaporizing a low temperature heat medium and surely putting the low temperature heat medium delivered from the heat exchanger into a gas phase state in the heat exchanger having a horizontal shell-and-tube structure with a possibility that the low temperature heat medium which is a temperature rise target, flows in a gas-liquid mixed phase state into the heat exchanger.SOLUTION: Bar-like members stopping a low temperature heat medium in a liquid phase state and forming a liquid surface are provided among heat transfer tube groups, and each bar-like member is provided with a plurality of vertical through-holes.

Description

  An outer cylinder extending in the horizontal direction, and a heat transfer tube group including a plurality of heat transfer tubes disposed in the outer cylinder and through which the high temperature heat medium flows, and the high temperature heat medium received from the high temperature heat medium inlet is in the heat transfer tube group. Shell-and-tube heat exchanger that heats the low-temperature heat medium flowing into the low-temperature heat medium advection space formed between the outer cylinder and the heat transfer tube group and discharges it as a heated gas outside The heating gas with the gas amount corresponding to the amount of the low temperature heat medium flowing into the low temperature heat medium advection space is discharged to the outside, and the low temperature heat medium flows into the low temperature heat medium advection space in a gas-liquid mixed phase state. It relates to a heat exchanger.

As an example of this type of heat exchanger, there are a heater 11 described in Patent Document 1 and a gas overheat heat exchanger 11 described in Patent Document 2. The heat exchangers disclosed in these documents have a structure in which the temperature of the low-temperature heat medium evaporated and vaporized by the evaporator (vaporizer) is raised by the high-temperature heat medium. The horizontal shell and tube structure is used.
That is, a high-temperature heat medium received from a high-temperature heat medium inlet is provided with an outer cylinder that extends in the horizontal direction and a heat transfer tube group that is arranged in the outer cylinder and that includes a plurality of heat-transfer tubes through which the high-temperature heat medium (seawater) flows. (Seawater) flows through the heat transfer tube group, warming the low temperature heat medium (natural gas) flowing into the low temperature heat medium advection space formed between the outer body and the heat transfer tube group To the outside.
A conventional shell-and-tube heat exchanger is shown in FIG. 4 corresponding to the present application.

JP-A-8-269468 JP 2002-309276 A

The above equipment is equipment for obtaining vaporized natural gas (NG) and calorie-adjusted city gas from liquefied natural gas (LNG), but is generally in a gas-liquid mixed phase state or almost vaporized state. In the heat exchanger that raises the temperature of the low-temperature heat medium to be heated by the high-temperature heat medium, the operating state upstream of the heat exchanger changes, or the temperature condition of the surrounding environment changes, There is a case where a low-temperature heat medium in a liquid phase state more than planned as a design condition flows into the heat exchanger.
In such a state, the heat load increases, and the low temperature heat medium accumulates at the bottom of the heat exchanger outer trunk, partially freezes the high temperature heat medium in the heat transfer tube, or destabilizes the operation state. There is a fear. When such an abnormal state occurs, the operation state of the entire system including the heat exchanger is greatly affected, which is not preferable.

  An object of the present invention is a heat exchanger having a horizontally placed shell and tube structure, in which a low temperature heat medium to be heated may flow into the heat exchanger in a gas-liquid mixed phase state. An object of the present invention is to obtain a heat exchanger that can reliably bring the low-temperature heat medium sent from the heat exchanger into a gas phase state without accumulating the low-temperature heat medium at the bottom of the outer copper in the heat exchanger.

To achieve the above purpose,
An outer cylinder extending in the horizontal direction; and a heat transfer tube group including a plurality of heat transfer tubes arranged in the outer cylinder and through which the high-temperature heat medium flows, wherein the high-temperature heat medium received from a high-temperature heat medium inlet is the heat transfer tube A shell-and-tube that heats a low-temperature heat medium flowing into a low-temperature heat medium advection space formed between the outer cylinder and the heat transfer tube group in a state of flowing in the group and discharges it as a heated gas to the outside. Configured as a heat exchanger,
In the configuration in which the heated gas in a gas amount corresponding to the amount of the low temperature heat medium flowing into the low temperature heat medium advection space is released to the outside,
The characteristic configuration of the heat exchanger in which the low-temperature heat medium may flow into the low-temperature heat medium advection space in a gas-liquid mixed phase state,
The heat transfer tube group is provided with a rod-shaped member that receives a low-temperature heat medium in a liquid phase and forms a liquid surface.

In the heat exchanger of this configuration, when the low-temperature heat medium of the low-temperature heat medium in the liquid phase enters the low-temperature heat medium advection space, the liquid is received by the rod-shaped member, and is received by the rod-shaped member, A liquid level is formed. On the other hand, the low-temperature heat medium in a gas phase mainly exchanges heat with the high-temperature heat medium flowing in the heat transfer tube, and the temperature is sequentially increased. Therefore, the warming gas formed in this way flows in a state of being in contact with the surface of the low-temperature heat medium liquid formed on the rod-like member. Vaporization (evaporation) is promoted.
As a result, it was possible to obtain a heat exchanger capable of reliably vaporizing the low-temperature heat medium and reliably bringing the low-temperature heat medium sent from the heat exchanger into a gas phase state.

In this heat exchanger, it is preferable that a plurality of through holes in the vertical direction are provided in the rod-shaped member.
Here, the vertical direction does not mean a through-hole formed in a completely vertical direction,
From the liquid phase low-temperature heat medium liquid pool formed on the upper side of the rod-shaped member, the low-temperature heat medium liquid descends and drops to the lower side of the rod-shaped member. The through-hole inlet into which the low-temperature heat medium liquid flows from the liquid reservoir only needs to be located above the through-hole outlet from which the liquid flows out. It is desirable to design the size and interval of the through holes in consideration of the operation state of the heat exchanger.

  By providing such a through hole, the low-temperature heat medium in the liquid phase state is sequentially moved from the rod-shaped member positioned on the upper side to the rod-shaped member positioned on the lower side, and while sequentially forming the liquid surface, Vaporization (evaporation) can be promoted.

In this type of heat exchanger, it is preferable that the rod-like member is supported by a tube plate that supports the plurality of heat transfer tubes.
In horizontal and shell-and-tube heat exchangers, basically, the low-temperature heat medium in the vapor phase is horizontally in the low-temperature heat medium advection space, and the high-temperature heat medium is horizontally in the heat transfer tube group. A structure that moves in the direction (from one tube sheet to the other tube sheet) is employed. In such a horizontal advection, in a structure in which a plurality of baffles are provided in a direction perpendicular to the outer cylinder axis direction, the low-temperature heat medium flows through a zigzag path that repeats advection in the vertical direction and the horizontal direction. In some cases, the advection in the horizontal direction as a whole. Therefore, the low-temperature heat medium in the gas phase basically becomes a heated gas along with the horizontal advection.
Therefore, by providing the rod-shaped member across the tube plates, it is possible to ensure the opportunity of contact between the heated gas and the low-temperature heat medium in the liquid phase, and the low-temperature heat medium is separated from the inlet nozzle. Vaporization (evaporation) can be realized satisfactorily because the heat transfer tubes located at different positions can be dispersed and contacted.

Here, it is preferable that the rod-shaped member is a U-shaped bowl-shaped member formed in a U shape whose cross-sectional shape opens upward when viewed in the longitudinal direction.
The liquid surface can be satisfactorily formed by using the concave portion on the upper side of the U-shaped bowl-shaped member as a reservoir for the low-temperature heat medium in the liquid phase.

It is also preferable that the rod-shaped member includes at least a pair of weir members extending obliquely upward as viewed in the longitudinal direction, and forming a liquid receiving portion that receives the low-temperature heat medium in the liquid phase state between the pair of weir members.
At least a pair of dam members are provided, and a liquid receiving part that receives the low-temperature heat medium in the liquid phase is formed between the pair of dam members, so that the low-temperature heat medium in the liquid phase is formed. As the storage part, the liquid level can be satisfactorily formed.

  The arrangement of such rod-shaped members in the outer cylinder is a configuration in which a plurality of the rod-shaped members are distributed in the vertical and horizontal directions as viewed in the cylinder axis direction of the outer cylinder, or are distributed based on specific rules. By adopting, the space in the outer cylinder can be used effectively to vaporize (evaporate) the low-temperature heat medium well.

The longitudinal cross-sectional view along the longitudinal direction of the heat exchanger tube which shows the structure of the heat exchanger which concerns on embodiment. The longitudinal cross-sectional view of the direction orthogonal to the heat exchanger tube which shows the structure of the heat exchanger which concerns on embodiment. The longitudinal cross-sectional view which shows the detailed structure of a bowl-shaped member. The schematic diagram of the heat exchanger of the conventional shell and tube structure.

  The heat exchanger 100 according to the present application will be described below with reference to the drawings.

  As shown in FIG. 1, a heat exchanger 100 according to the present application includes a heat transfer tube group including an outer cylinder 3 that extends in the horizontal direction and a plurality of heat transfer tubes 4 that are arranged in the outer cylinder 3 and through which a high-temperature heat medium flows. 40, and the high temperature heat medium received from the high temperature heat medium inlet 5 flows into the heat transfer tube group 40 and flows into the low temperature heat medium advection space 50 formed between the outer body 3 and the heat transfer tube group 40. The structure is adopted.

  In these drawings, a pair of tube plates 6 are provided on the left and right ends of the outer body 3, and the high temperature heat medium chambers connected to the high temperature heat medium inlets 5 respectively on the side ends in the lateral direction from the tube plates 6. 7 and a high-temperature heat medium chamber 9 connected to the high-temperature heat medium outlet 8 are provided. Further, a heat transfer tube group 40 is provided between the pair of tube plates 6. Accordingly, the high temperature heat medium h flowing into the high temperature heat medium chamber 7 from the high temperature heat medium inlet 5 flows through the heat transfer tube group 40, flows into the high temperature heat medium chamber 9, and flows out from the high temperature heat medium outlet 8.

A space formed outside the pair of tube plates 6 and the heat transfer tube group 40 in the outer body 3 is configured as a low-temperature heat medium advection space 50. An example of such a low-temperature heat medium c is natural gas in a gas-liquid mixed phase state.
A low-temperature heat medium inlet 10 and a heated gas discharge port 11 are provided at the upper part of the outer cylinder 3.
As the medium moves in the low-temperature heat medium advection space 50, the low-temperature heat medium c is heated and heated by the high-temperature heat medium h flowing in the heat transfer tube 4, and is heated as a heated gas w. 11 is discharged to the outside.

The heated gas w having a gas amount corresponding to the total amount of the low-temperature heat medium c flowing into the low-temperature heat medium advection space 50 is released to the outside.
That is, the heated gas w corresponding to the amount of the low-temperature heat medium c fed into the low-temperature heat medium advection space 50 per unit time is sent out from the heat exchanger 100 in the unit time.

  The heat exchanger 100 according to the present application includes a flange-like member 30 (an example of a rod-like member) provided across the tube plate 6 between the heat transfer tube groups 40.

Hereinafter, the characteristic configuration of the heat exchanger according to the present application will be described in more detail.
As can be seen from FIGS. 1 and 2, in the heat exchanger 100 according to the present application, a bowl-shaped member 30 that receives the low-temperature heat medium c in the liquid phase and forms a liquid surface is provided between the heat transfer tube groups 40. It has been.
As shown in FIG. 2, the bowl-shaped members 30 are arranged in an appropriate manner dispersed in the outer body 3, and are in a liquid phase state where they are dropped from the outer peripheral surface of the heat transfer tube 4 or from another bowl-shaped member 30. It is configured to receive the low-temperature heat medium c.
FIG. 3 shows the cross-sectional shapes of the hook-shaped members 30. In the example shown in FIG. 3A, the hook-shaped members 30 are shown in the upper direction as viewed in the longitudinal direction (viewed in the axial direction of the outer cylinder 3). It is configured as a U-shaped bowl-shaped member 30a formed in an open U-shape. A plurality of vertical through holes 31 are provided in the bowl-shaped member 30a.

  In the example shown in FIG. 3B, the hook-shaped member 30 is configured as a star-shaped hook-shaped member 30b that exhibits a star-shaped cross section when viewed in the longitudinal direction (viewed in the axial direction of the outer cylinder 3). Specifically, in the star-shaped bowl-shaped member 30b in this example, the plate-shaped members 36a are radially distributed around the periphery of the rod-shaped member main body 35, and the plate-shaped members 36a located on the upper side are used as the weir members. A liquid receiving portion 38 is formed between the plate-like members 36a.

[Another embodiment]
(1) In the embodiment described so far, an example in which the high-temperature heat medium flows from the right to the left has been described. However, a structure in which the high-temperature heat medium flows from the left to the right may be adopted.
(2) FIG. 3A shows an example in which vertical holes 31 are provided radially downward in the U-shaped bowl-shaped member 30a. Of course, also in the star-shaped bowl-shaped member 30b (an example of the rod-shaped member) shown in FIG. 3B, a through-hole may be provided in the plate-shaped member 36 constituting the dam member.
Therefore, the rod-shaped member referred to in the present application has a shape having a function of increasing the gas-liquid contact time until the liquid falls to the outer trunk bottom part and enhancing the liquid dispersion function in the outer trunk, separately from the heat transfer tube. For example, the shape is not particularly limited, and it may be configured as a rod having a longitudinal axis.

  A heat exchanger having a horizontal shell and tube structure, in which a low-temperature heat medium to be heated flows into the heat exchanger in a gas-liquid mixed phase state, and heat exchange is performed in the heat exchanger. It was possible to obtain a heat exchanger that can reliably bring the low-temperature heat medium sent from the heat exchanger into a gas-phase state without generating a liquid pool at the bottom of the outer shell in the chamber.

3 Outer Cylinder 4 Heat Transfer Tube 10 Low Temperature Heat Medium Inlet 11 Heated Gas Release 30 Gutter-Shaped Member (Bar-Shaped Member)
30a U-shaped bowl-shaped member (bar-shaped member)
30b Star-shaped bowl-shaped member (bar-shaped member)
31 Through-hole 35 Bar-shaped member body 36 Plate-shaped member (weir member)
38 Liquid receiving portion 40 Heat transfer tube group 50 Low temperature heat medium advection space

Claims (6)

An outer cylinder extending in the horizontal direction; and a heat transfer tube group including a plurality of heat transfer tubes arranged in the outer cylinder and through which the high-temperature heat medium flows, wherein the high-temperature heat medium received from a high-temperature heat medium inlet is the heat transfer tube A shell-and-tube that heats a low-temperature heat medium flowing into a low-temperature heat medium advection space formed between the outer cylinder and the heat transfer tube group in a state of flowing in the group and discharges it as a heated gas to the outside. Configured as a heat exchanger,
In the configuration in which the heated gas in a gas amount corresponding to the amount of the low temperature heat medium flowing into the low temperature heat medium advection space is released to the outside,
The heat exchanger in which the low temperature heat medium may flow into the low temperature heat medium advection space in a gas-liquid mixed phase state,
A heat exchanger in which a rod-shaped member that receives a low-temperature heat medium in a liquid phase and forms a liquid surface is provided between heat transfer tube groups.   The heat exchanger according to claim 1, wherein the rod-shaped member is provided with a plurality of vertical through holes.   The heat exchanger according to claim 1 or 2, wherein the rod-like member is supported by a tube plate that supports the plurality of heat transfer tubes.   The heat exchanger according to any one of claims 1 to 3, wherein the rod-shaped member is a U-shaped bowl-shaped member that is formed in a U-shape that opens upward as viewed in the longitudinal direction.   The rod-shaped member includes at least a pair of weir members extending obliquely upward as viewed in the longitudinal direction, and forms a liquid receiving portion that receives the low-temperature heat medium in the liquid phase state between the pair of weir members. The heat exchanger according to any one of 3.   The heat exchanger according to any one of claims 1 to 5, wherein a plurality of the rod-like members are dispersedly arranged in the vertical and horizontal directions, or are dispersedly arranged based on a specific rule, as viewed in the axial direction of the outer cylinder. .

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