WO2017090558A1

WO2017090558A1 - Moisture separator/heater

Info

Publication number: WO2017090558A1
Application number: PCT/JP2016/084481
Authority: WO
Inventors: 圭吾西田; 大智吉井; 石黒　達男; 太一中村
Original assignee: 三菱日立パワーシステムズ株式会社
Priority date: 2015-11-25
Filing date: 2016-11-21
Publication date: 2017-06-01

Abstract

This moisture separator/heater is provided with a housing, a moisture separation device, a heating device, and a drain discharge device. The moisture separation device includes a lower moisture separation element that extends in a first horizontal direction, and an upper moisture separation element that extends in the first horizontal direction and is disposed above the lower moisture separation element. The drain discharge device includes: a lower drain head that extends in the first horizontal direction and protrudes from the lower moisture separation element in a second horizontal direction orthogonal to the first horizontal direction; an upper drain head that extends in the first horizontal direction and protrudes from the upper moisture separation element in the second horizontal direction; and at least one inner drain pipe that extends vertically between the upper drain head and the lower drain head and connects the upper drain head and the lower drain head.

Description

Moisture separator heater

This disclosure relates to a moisture separator heater.

The moisture separation heater is used in, for example, a nuclear power plant, and is configured to separate moisture from steam discharged from a high-pressure turbine and to heat dry steam to provide it to a low-pressure turbine.
As this type of moisture separation heater, for example, a moisture separator disclosed in Patent Document 1 has a moisture separation element, and the moisture separation element has a plurality of corrugated separator vanes. Further, the moisture separator has a heating tube group as a heating device downstream of the moisture separation element in the steam flow direction. Therefore, the dry steam from which moisture has been separated by the moisture separation element is heated when passing through the heating tube group.

On the other hand, the separator vane of the moisture separation element is supported by upper and lower support frames, and a drain opening is formed in the lower support frame. The moisture separated from the steam by the separator vane flows down as drain along the separator vane, and is discharged from the drain opening to the drain passage.

Further, in the moisture separator structure disclosed in Patent Document 2, corrugated plate-type steam separators are arranged so as to be shifted laterally in two upper and lower stages. In addition, a vertical drain pipe is provided in the separated water reservoir of the upper air / water separator, and a drainage short hanging from the separated water reservoir of the upper air / water separator is provided in an intermediate water collection box formed integrally with the separated water reservoir of the lower air / water separator. The tube is in contact.

International Publication No. 2008/026325 Japanese Utility Model Publication No. 61-98513

Also in the moisture separator disclosed in Patent Document 1, it is conceivable that the moisture separation elements are stacked in two stages up and down in order to increase the flow path area of the steam in the moisture separation element and the heating device. In this case, it becomes a problem how to smoothly drain the drain from each of the moisture separation elements stacked in two stages.

In view of the above circumstances, an object of at least one embodiment of the present invention is to provide a moisture separation heater provided with a drain discharge device capable of smoothly discharging drain from each of the moisture separation elements stacked in two stages above and below. There is to do.

(1) A moisture separator / heater according to at least one embodiment of the present invention comprises:
A housing with a steam channel defined therein;
A moisture separator arranged in the steam flow path and capable of separating the moisture from steam containing moisture;
A heating device that is positioned downstream of the moisture separator and disposed in the steam flow path and capable of heating the steam;
A drain discharger capable of discharging the moisture separated by the moisture separator out of the housing;
With
The moisture separator is
A lower moisture separation element extending in a first horizontal direction;
An upper moisture separation element extending in the first horizontal direction and disposed above the lower moisture separation element;
Including
The drain discharge device
A lower drain header portion protruding from the lower moisture separation element in a second horizontal direction orthogonal to the first horizontal direction and extending in the first horizontal direction;
An upper drain header portion protruding from the upper moisture separation element in the second horizontal direction and extending in the first horizontal direction;
At least one internal drain pipe extending in the vertical direction between the upper drain header portion and the lower drain header portion and communicating between the upper drain header portion and the lower drain header portion;
including.

According to the configuration (1), the drain collected by the upper moisture separation element is discharged through the upper drain header portion protruding from the upper moisture separation element, and the drain collected by the lower moisture separation element is It is discharged through a lower drain header portion protruding from the moisture separation element. For this reason, the drain collected by the upper moisture separation element does not flow down the lower moisture separation element as it is, and the drain once collected by the upper moisture separation element passes through the lower moisture separation element. To be taken away.
The internal drain pipe extends vertically between the upper drain header section and the lower drain header section, and the internal drain pipe can be disposed near the lower moisture separation element. For this reason, it is suppressed by the internal drain pipe that the flow of steam is hindered downstream of the lower moisture separation element, and the pressure loss in the moisture separation heater is reduced.
Furthermore, since the internal drain pipe can be disposed near the lower moisture separation element, the protruding length of the upper drain header portion in the second horizontal direction can be made relatively short. For this reason, even if the upper drain header portion protrudes in the second horizontal direction, the upper drain header portion can be firmly supported.

(2) In some embodiments, in the configuration (1),
In the at least one internal drain pipe, the drain flowing down at least the upper end side of the at least one internal drain pipe flows down in a film shape along the inner peripheral surface of the upper end side of the at least one internal drain pipe. It is configured as follows.
In the configuration (2), since the internal drain pipe is configured such that the drain flows down in a film shape on the upper end side of the internal drain pipe, the drain flowing down the internal drain pipe is prevented from entraining steam. . For this reason, since generation | occurrence | production and extinction of the bubble in an internal drain pipe, and a raise of a bubble are suppressed, a drain can flow stably in an internal drain pipe. For this reason, according to the said structure (2), the drain collected with the upper stage moisture separation element can be smoothly discharged | emitted through an internal drain pipe.

(3) In some embodiments, in the configuration (1) or (2),
The upper drain header portion has an upper drain header outlet that communicates with the internal drain pipe,
The drain discharge device
Two or more pieces positioned on both sides of the upper drain header outlet in the first horizontal direction and disposed on the bottom surface of the upper drain header portion and partially surrounding the upper drain header outlet in the circumferential direction It further includes a protrusion.

When the flow rate of the drain flowing into the upper drain header portion increases, the drain that flows from both sides toward the upper drain header outlet in the first horizontal direction (longitudinal direction of the upper drain header portion) becomes 2 on both sides in the longitudinal direction. It flows into the upper drain header outlet from the location. And the flow of the drain which flowed into the upper drain header outflow port from both sides in the longitudinal direction merges in the internal drain pipe, and it becomes difficult to form self-bending. In this respect, according to the configuration (3), two protrusions are provided on both sides of the first horizontal direction, the flow of drain in the first horizontal direction is weakened, and the drain is circumferential with respect to the internal drain pipe. It will flow evenly. Thereby, the drain flowing down the upper end side of the internal drain pipe can flow down in a film shape along the inner peripheral surface of the upper end side of the internal drain pipe.

(4) In some embodiments, in any one of the configurations (1) to (3),
The area of the lower drain header inlet that communicates the lower drain header part and the at least one internal drain pipe is the area of the upper drain header outlet that communicates the upper drain header part and the at least one internal drain pipe. Smaller than.
In the configuration (4), since the area of the lower drain header inlet is smaller than the area of the upper drain header outlet, the drain flowing down the internal drain pipe can be temporarily stored on the lower end side of the inner drain pipe. it can. Thereby, even if the steam flows into the lower drain header portion together with the drain, the steam is suppressed from rising in the internal drain pipe. As a result, the backflow of the drain in the internal drain pipe is suppressed, and the drain collected by the upper moisture separation element can be smoothly discharged through the internal drain pipe.

(5) In some embodiments, in any one of the configurations (1) to (4),
The drain discharge device further includes a water seal portion capable of sealing the lower end portion of the at least one internal drain pipe.
In the configuration (5), since the lower end portion of the internal drain pipe is sealed by the water seal portion, even if the steam flows into the lower drain header portion together with the drain, the steam is suppressed from rising in the internal drain pipe. The As a result, the backflow of the drain in the internal drain pipe is suppressed, and the drain collected by the upper moisture separation element can be smoothly discharged through the internal drain pipe.

(6) In some embodiments, in the configuration (5),
The water sealing portion is configured by a cup that surrounds a lower end portion of the at least one internal drain pipe and can temporarily store drain that has flowed down in the at least one internal drain pipe.
The ceiling wall of the lower drain header portion has a stepped shape, so that the lower moisture level is higher in the second horizontal direction than the high ceiling portion located on the lower moisture separation element side and the higher ceiling portion. A low ceiling portion located far from the separation element and located below in the vertical direction;
The drain discharge device further includes a shielding plate disposed above the upper end opening of the cup so as to face the upper end opening of the cup at a distance.

In the above configuration (6), when viewed from above, the upper end opening of the cup constituting the water sealing portion is completely hidden by the shielding plate. As a result, it is possible to stabilize the water seal by preventing the fluctuation of the water surface caused by the drain dripping from above hitting the water surface of the drain stored in the cup, or to avoid the re-scattering of the drain from the water surface. it can.

(7) In some embodiments, in the configuration (5) or (6),
The water sealing portion is configured by a cup that surrounds a lower end portion of the at least one internal drain pipe and can temporarily store drain that has flowed down in the at least one internal drain pipe.
The ceiling wall of the lower drain header portion has a stepped shape, so that the lower moisture level is higher in the second horizontal direction than the high ceiling portion located on the lower moisture separation element side and the higher ceiling portion. A low ceiling portion located far from the separation element and located below in the vertical direction;
At least the high ceiling portion of the ceiling wall has an opening edge at a position corresponding to the at least one internal drain pipe in the first horizontal direction,
The drain discharge device further includes a baffle plate extending downward from an opening edge of the high ceiling portion.

In the portion where the internal drain pipe passes in the vertical direction, at least the high ceiling portion of the lower drain header portion is interrupted in the first horizontal direction (longitudinal direction). There is a possibility that the drain bounced off from the surface of the drain stored in the cup will flow backward from this interrupted portion. In this respect, in the configuration (7), the bounce plate extending downward from the opening edge of the high ceiling portion can prevent the drain bounced back from the surface of the drain stored in the cup from flowing back. .

(8) In some embodiments, in any one of the configurations (1) to (7),
The drain discharge device
An assembly part connected to a part of the lower drain header part and projecting downward from the lower drain header part,
A drain discharge pipe extending downward from the gathering portion;
Is further included.
In the configuration (8), since the collecting portion protruding downward from the lower drain header portion is provided, the drain in the lower drain header portion 52 flows into the collecting portion. Thereby, it is possible to prevent the drain from being excessively accumulated in the lower drain header portion, and it is possible to smoothly drain the drain in the lower drain header portion.

(9) In some embodiments, in the configuration (8),
A bottom surface of the lower drain header portion extends while being inclined with respect to the first horizontal direction so as to gradually become lower toward the collecting portion.
In the configuration (9), since the bottom surface of the lower drain header portion is inclined with respect to the first horizontal direction, the drain can be discharged smoothly through the collecting portion.

According to at least one embodiment of the present invention, there is provided a moisture separation heater provided with a drain discharge device capable of smoothly discharging drain from each of the moisture separation elements stacked in two stages.

It is a figure which shows schematic structure of the secondary steam circulation system of the nuclear power plant to which the moisture separation heater which concerns on one Embodiment of this invention was applied. It is a schematic cross-sectional view of a moisture separation heater. FIG. 3 is a schematic sectional view taken along line III-III in FIG. 2. FIG. 4 is a schematic sectional view taken along line IV-IV in FIG. 2. FIG. 5 is a schematic sectional view taken along line VV in FIG. 2. FIG. 3 is a schematic cross-sectional view taken along line VI-VI in FIG. 2. It is a partial notch perspective view which shows the schematic structure of the moisture separation element applied to the moisture separation heater of FIG. It is sectional drawing which shows schematically the structure of the drain discharge device applied to the moisture separation heater of FIG. 1 with a moisture separator. It is a top view which shows roughly a part of structure of the drain discharge device seen in the direction of the arrow IX in FIG. It is a figure for demonstrating an example of the mode of the drain which flows down the inside drain pipe. It is a figure for demonstrating the structure of the drain discharge apparatus of other one Embodiment corresponding to sectional drawing which follows the XI-XI line in FIG. It is a perspective view which shows roughly the structure of the upper stage drain header outflow port periphery of the drain discharge apparatus of FIG. It is sectional drawing which shows schematically a part of drain discharge device applicable to the moisture separation heater which concerns on other embodiment. It is a figure equivalent to FIG. 9 of the drain discharge apparatus applicable to the moisture separation heater which concerns on other embodiment. It is sectional drawing which shows schematically the structure of the drain discharge device which concerns on other one Embodiment with a moisture separator. FIG. 16 is a plan view schematically showing a part of the configuration of the drainage device as seen in the direction of arrow XVI in FIG. 15. It is a figure which expands and shows the lower stage drain header part periphery in FIG. FIG. 18 is a view corresponding to FIG. 17, schematically showing a drain discharge device according to another embodiment. FIG. 18 is a view corresponding to FIG. 17, schematically showing a drain discharge device according to another embodiment. FIG. 20 is a plan view schematically showing a part of the configuration of the drainage device as viewed in the direction of arrow XX in FIG. 19.

Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described in the embodiments or shown in the drawings are not intended to limit the scope of the present invention, but are merely illustrative examples. Absent.
For example, expressions expressing relative or absolute arrangements such as “in a certain direction”, “along a certain direction”, “parallel”, “orthogonal”, “center”, “concentric” or “coaxial” are strictly In addition to such an arrangement, it is also possible to represent a state of relative displacement with an angle or a distance such that tolerance or the same function can be obtained.
For example, an expression indicating that things such as “identical”, “equal”, and “homogeneous” are in an equal state not only represents an exactly equal state, but also has a tolerance or a difference that can provide the same function. It also represents the existing state.
For example, expressions representing shapes such as quadrangular shapes and cylindrical shapes represent not only geometrically strict shapes such as quadrangular shapes and cylindrical shapes, but also irregularities and chamfers as long as the same effects can be obtained. A shape including a part or the like is also expressed.
On the other hand, the expressions “comprising”, “comprising”, “comprising”, “including”, or “having” one constituent element are not exclusive expressions for excluding the existence of the other constituent elements.

FIG. 1 shows a schematic configuration of a secondary steam circulation system 2 of a nuclear power plant to which a moisture separation heater 1 according to an embodiment of the present invention is applied.
The secondary steam circulation system 2 has, for example, a circulation path 4 through which water as a working fluid circulates with phase transformation. The circulation path 4 includes a steam generator 6, a high-pressure turbine 8, and a moisture separation heater. 1, the low-pressure turbine 10, the condenser 12, the deaerator 14, the feed water pump 16, and the high temperature heater 18 are inserted in this order in the flow direction of water. The high-pressure turbine 8 and the low-pressure turbine 10 are connected to a generator 20, and can generate electric power by driving the generator 20 using the steam generated by the steam generator 6.
On the other hand, the moisture separator 1 can remove moisture from the steam containing moisture discharged from the high-pressure turbine 8 and supply dry steam to the low-pressure turbine 10.

Here, FIG. 2 shows a schematic cross section of the moisture separator heater 1. FIG. 3 is a schematic cross-sectional view taken along line III-III in FIG. FIG. 4 is a schematic sectional view taken along line IV-IV in FIG. FIG. 5 is a schematic cross-sectional view taken along the line VV in FIG. FIG. 6 is a schematic cross-sectional view taken along the line VI-VI in FIG. FIG. 7 is a partially cutaway perspective view showing a schematic configuration of a moisture separation element 27 applied to the moisture separation heater 1 of FIG. 1.

As shown in FIGS. 2 to 6, the moisture separation heater 1 includes a housing 24, a moisture separation device 26, a heating device 28, and a drain discharge device 30, and a manifold as necessary. 32.
The housing 24 has, for example, a cylindrical shape, and is placed horizontally so that the axial direction of the housing 24 matches the horizontal direction. The housing 24 is provided with a steam inlet 34 for steam containing moisture (wet steam) and a steam outlet 36 for steam (dry steam) from which moisture has been removed and heated. A steam flow path 38 for steam extending from the steam inlet 34 to the steam outlet 36 is defined inside the housing 24. For example, the steam inlet 34 is provided at one end of the housing 24, and the steam outlet 36 is provided in the center of the housing 24 in the axial direction (first horizontal direction). The steam outlet 36 is opened, for example, in the horizontal direction.

The manifold 32, the moisture separator 26, and the heating device 28 are accommodated in the housing 24, and are arranged in the steam flow path 38 in this order in the flow direction of the steam. For example, the manifold 32, the moisture separator 26, and the heating device 28 are sequentially arranged in a horizontal direction (second horizontal direction) orthogonal to the axial direction of the housing 24.
The manifold 32 is made of, for example, punching metal and has a function of distributing wet steam to the entire moisture separator 26. The punching metal extends, for example, in the vertical direction and the axial direction of the housing 24, and divides the interior of the housing 24 into two regions adjacent to each other in the horizontal direction. In this case, the wet steam sequentially passes through the punching metal, the moisture separator 26 and the heater 28 in the second horizontal direction, and flows out from the steam outlet 36 in the horizontal direction.

The moisture separator 26 can separate moisture from steam containing moisture. The moisture separator 26 has two moisture separation elements 27 stacked in two stages, ie, a lower moisture separation element 27a and an upper moisture separation element 27b.
The lower moisture separation element 27 a extends in the axial direction (first horizontal direction) of the housing 24.
The upper moisture separation element 27b extends in the axial direction of the housing 24 and is disposed above the lower moisture separation element 27a.
The lower moisture separation element 27a and the upper moisture separation element 27b can be configured by the moisture separation element 27, respectively. In this case, two moisture separation elements 27 are stacked one above the other.

As shown in FIG. 7, the moisture separation element 27 includes a plurality of vanes 40, a lower frame 42, an upper frame 44, and holding

portions

46 and 47.
The vane 40 is, for example, a chevron vane, and is configured by a plate bent so as to have a plurality of peaks and valleys. The plurality of vanes 40 are arranged in the axial direction (first horizontal direction) of the housing 24 with a gap between them. The gaps between the vanes 40 extend in a zigzag manner in a horizontal direction (second horizontal direction) orthogonal to the axial direction of the housing 24, and moisture contained in the steam flows through the gaps between the vanes 40. Separated from the steam. And the separated moisture flows down along the vane 40 as a drain.

Each of the lower frame 42 and the upper frame 44 has a U-shaped cross section and extends in the axial direction of the housing 24. The lower frame 42 and the upper frame 44 sandwich the plurality of vanes 40 in the vertical direction while being separated from each other in the vertical direction. Therefore, the steam can flow in the second horizontal direction between the lower frame 42 and the upper frame 44.
The holding

portions

46 and 47 are attached to the inside of the

side walls

42 a and 44 a of the lower frame 42 and the upper frame 44, and have a plurality of notches that can receive the side edges of the vane 40. With the side edges of the vanes 40 engaged with the notches, the vanes 40 are held with a gap between them.

The heating device 28 is located in the downstream of the moisture separator 26 and is disposed in the steam flow path 38, and can heat the steam. The heating device 28 includes a heating medium header 48 and a plurality of heating medium tubes 50 connected to the heating medium header 48. High temperature steam as a heating medium is supplied to the plurality of heating medium tubes 50 through the heating medium header 48, and the steam that has passed through the moisture separator 26 passes through the gaps between the heating medium tubes 50. To be heated. That is, the heating device 28 is configured by a tube-type heat exchanger.
In the present embodiment, the two heating devices 28 are arranged in series downstream of the moisture separator 26.

The drain discharge device 30 can discharge the moisture separated by the moisture separation device 26 out of the housing 24.
Here, FIG. 8 is a cross-sectional view schematically showing the configuration of the drain discharge device 30a together with the moisture separation device 26 as one embodiment of the drain discharge device 30 applied to the moisture separation heater 1 of FIG. It is.
FIG. 9 is a plan view schematically showing a part of the configuration of the drain discharge device 30a as viewed in the direction of the arrow IX in FIG.
FIG. 10 is a view for explaining an example of the state of the drain flowing down in the internal drain pipe 56 in the drain discharge device 30a.
FIG. 11 is a view for explaining a configuration of a drain discharge device 30b as an embodiment of the drain discharge device 30 corresponding to a cross-sectional view taken along the line XI-XI in FIG.
FIG. 12 is a perspective view schematically showing a configuration around the upper drain header outlet 54a of the drain discharge device 30b.
FIG. 13 is a cross-sectional view schematically showing a part of a drain discharge device 30c according to another embodiment.
FIG. 14 is a view corresponding to FIG. 9 schematically showing a drain discharge device 30d according to another embodiment.
FIG. 15 is a cross-sectional view schematically showing the configuration of the drain discharge device 30e according to another embodiment together with the moisture separator 26.
FIG. 16 is a plan view schematically showing a part of the configuration of the drain discharge device 30e as seen in the direction of the arrow XVI in FIG.
FIG. 17 is an enlarged view showing the periphery of the lower drain header portion 52 in FIG.
FIG. 18 is a view corresponding to FIG. 17 schematically showing a drain discharge device 30f according to another embodiment.
FIG. 19 is a view corresponding to FIG. 17 schematically showing a drain discharge device 30g according to another embodiment.
FIG. 20 is a plan view schematically showing a part of the configuration of the drain discharge device 30g as seen in the direction of the arrow XX in FIG.
In the following description, the drain discharge devices 30a to 30g are collectively referred to as the drain discharge device 30.

As shown in FIGS. 8, 9, 14 to 16 and 20, the drain discharge device 30 includes a lower drain header portion 52, an upper drain header portion 54, and at least one internal drain pipe 56. .
The lower drain header portion 52 protrudes from the lower moisture separation element 27a in a second horizontal direction orthogonal to the axial direction (first horizontal direction) of the housing 24, and extends in the first horizontal direction. The lower drain header portion 52 defines a lower drain channel 58 extending along the lower moisture separation element 27a on the side of the bottom of the lower moisture separation element 27a.
Note that the lower drain header portion 52 is positioned adjacent to the downstream side of the lower frame 42 of the lower moisture separation element 27a in the flow direction of the steam passing through the lower moisture separation element 27a.

The upper drain header portion 54 protrudes from the upper moisture separation element 27b in the second horizontal direction and extends in the first horizontal direction. The upper drain header portion 54 defines an upper drain flow path 60 extending along the upper moisture separation element 27b on the side of the bottom of the upper moisture separation element 27b.
Note that the upper drain header portion 54 is positioned adjacent to the downstream side of the lower frame 42 of the upper moisture separation element 27b in the flow direction of the steam passing through the upper moisture separation element 27b.

The internal drain pipe 56 extends in the vertical direction between the upper drain header portion 54 and the lower drain header portion 52, and is provided at the upper drain header outlet 54 a and the lower drain header portion 52 provided in the upper drain header portion 54. The lower drain header inflow port 52a is in communication. That is, the internal drain pipe 56 communicates between the lower drain channel 58 and the upper drain channel 60. The plurality of internal drain pipes 56 are arranged at intervals in the axial direction of the housing 24.

On the other hand, the lower drain flow path 58 communicates with the inside of the lower frame 42 through a drain hole 62 that penetrates the side wall 42 a of the adjacent lower frame 42. Similarly, the upper drain flow path 60 communicates with the inside of the lower frame 42 through a drain hole 64 that penetrates the side wall 42 a of the adjacent lower frame 42.
Further, the lower drain flow path 58 communicates with the inside of the lower frame 42 through the side wall 42a of the adjacent lower frame 42 and, if necessary, the gas vent hole 66 penetrating the holding member 46. The gas vent hole 66 is located above the drain hole 62. Similarly, the upper drain flow path 60 communicates with the inside of the lower frame 42 through the side wall 42a of the adjacent lower frame 42 and, if necessary, the gas vent hole 68 that penetrates the holding member 47. The gas vent hole 68 is located above the drain hole 64.

According to the above configuration, the drain collected by the upper moisture separation element 27b is discharged through the upper drain header portion 54 protruding from the upper moisture separation element 27b, and the drain collected by the lower moisture separation element 27a is It is discharged through the lower drain header portion 52 protruding from the lower moisture separation element 27a. For this reason, the drain collected by the upper moisture separation element 27b does not flow down the lower moisture separation element 27a as it is, and the drain once collected by the upper moisture separation element 27b becomes lower. It is prevented from being taken away by steam passing through the.

Further, the internal drain pipe 56 extends in the vertical direction between the upper drain header section 54 and the lower drain header section 52, and the internal drain pipe 56 can be disposed near the lower moisture separation element 27a. For this reason, it is suppressed by the internal drain pipe | tube 56 that the flow of a vapor | steam is interrupted downstream of the lower stage moisture separation element 27a, and the pressure loss in the moisture separation heater 1 is reduced.
Furthermore, since the internal drain pipe 56 can be disposed near the lower moisture separation element 27a, the protruding length of the upper drain header portion 54 in the second horizontal direction can be made relatively short. For this reason, even if the upper drain header portion 54 protrudes in the second horizontal direction, the upper drain header portion 54 can be firmly supported.

In some embodiments, as shown in FIG. 10, the internal drain pipe 56 has a drain flowing down at least the upper end side of the internal drain pipe 56 along the inner peripheral surface on the upper end side of the internal drain pipe 56. It is configured to flow down like a film. That is, the internal drain pipe 56 is configured such that the drain flows down along the inner peripheral surface of the internal drain pipe 56 without the whole inside of the internal drain pipe 56 being filled with drain. Such draining down into a film is also called self-bending.

In the above configuration, the internal drain pipe 56 is configured such that the drain flows down in the form of a film at the upper end side of the internal drain pipe 56, so that the drain flowing down the internal drain pipe 56 is prevented from entraining steam. . For this reason, the generation and disappearance of bubbles in the internal drain pipe 56 and the rise of the bubbles are suppressed, so that the drain can flow stably in the internal drain pipe 56. For this reason, according to the said structure, the drain collected by the upper stage moisture separation element 27b through the internal drain pipe 56 can be discharged | emitted smoothly.
In some embodiments, the flow area of each internal drain pipe 56, the number of internal drain pipes 56, and the like are set so that self-bending is realized.

In order to realize self-bending, the limit value (limit Fr number) of the fluid number (Fr number) in the internal drain pipe 56 capable of realizing self-bending is experimentally obtained, and the Fr number becomes equal to or less than the limit Fr number. Should be designed as follows.
The Fr number is the ratio of inertial force and gravity, the apparent flow velocity (m / s) in the internal drain pipe 56 is Up, the inner diameter (m) of the internal drain pipe 56 is Du, and the gravitational acceleration (m / s ² ) Is g, the Fr number is given by the following formula:
Fr = Up / (Du × g) ^0.5
It is represented by
Here, the flow rate Q of the drain is fixed according to the specification of the plant to which the moisture separator / heater 1 is applied, so that the number of the internal drain pipes 56 is n, the following formula:
Q = 0.25π × Du ^ 2 × n × Up
It is represented by
Therefore, self-bending can be realized by selecting the number n of inner drain pipes 56 and the inner diameter Du so that the Fr number is equal to or less than the limit Fr number while taking the flow rate Q into consideration.

In some embodiments, as shown in FIGS. 11 and 12, the drain discharge device 30 further includes two or more protrusions 69. The protrusions 69 are disposed on both sides of the upper drain header outlet 54a in the first horizontal direction (longitudinal direction of the upper drain header portion 54), and are disposed so as to protrude upward from the bottom surface of the upper drain header portion 54. The drain header outlet 54a is partially surrounded in the circumferential direction. For example, the protrusion 69 is configured by a curved plate that is curved on an arc so as to follow the opening edge of the upper drain header outlet 54a.

When the flow rate of the drain flowing into the upper drain header portion 54 increases, the drain that has flowed from both sides toward the upper drain header outlet 54a in the first horizontal direction (the longitudinal direction of the upper drain header portion 54) becomes longer in the longitudinal direction. It flows into the upper drain header outlet 54a intensively from two places on both sides. And the flow of the drain which flowed into the upper stage drain header outlet 54a from the longitudinal direction both sides merges in the internal drain pipe 56, and it becomes difficult to form self-bending. In this regard, according to the above configuration, the two protrusions 69 are provided on both sides of the first horizontal direction, the flow of drain in the first horizontal direction is weakened, and the drain is evenly distributed in the circumferential direction with respect to the internal drain pipe 56. Will flow into. Thereby, the drain flowing down the upper end side of the internal drain pipe 56 can flow down in a film shape along the inner peripheral surface of the upper end side of the internal drain pipe 56. That is, the self-bending can be maintained by the protrusion 69.

In some embodiments, as shown in FIG. 8 or FIG. 10, the area of the lower drain header inlet 52 a that communicates the lower drain header portion 52 and the at least one internal drain pipe 56 is the upper drain header portion 54. Is smaller than the area of the upper drain header outlet 54 a that communicates with the at least one internal drain pipe 56.
In the above configuration, since the area of the lower drain header inlet 52a is smaller than the area of the upper drain header outlet 54a, the drain flowing down the internal drain pipe 56 can be temporarily stored on the lower end side of the internal drain pipe 56. it can. Thereby, even if the steam flows into the lower drain header portion 52 together with the drain, the steam is suppressed from rising in the internal drain pipe 56. As a result, the backflow of the drain in the internal drain pipe 56 is suppressed, and the drain collected by the upper moisture separation element 27 b can be smoothly discharged through the internal drain pipe 56.

In some embodiments, as shown in FIGS. 13, 15, and 17 to 19, the

drain discharge devices

30c, 30e, 30f, and 30g are water seals that can seal the lower end of the internal drain pipe 56. A portion 70 is further included.
In the above configuration, since the lower end portion of the internal drain pipe 56 is sealed by the water sealing part 70, even if the steam flows into the lower drain header part 52 together with the drain, the steam may rise in the internal drain pipe 56. It is suppressed. As a result, the backflow of the drain in the internal drain pipe 56 is suppressed, and the drain collected by the upper moisture separation element 27 b can be smoothly discharged through the internal drain pipe 56.
In some embodiments, the water seal portion 70 is constituted by a cup and is disposed so as to surround the lower end portion of the internal drain pipe 56. In this case, for example, the internal drain pipe 56 reaches the inside of the lower drain header portion 52, and the water seal portion 70 is disposed in the lower drain header portion 52.

In some embodiments, as shown in FIGS. 15 to 20, the ceiling wall of the lower drain header portion 52 has a stepped shape so that the high ceiling portion 78a located on the lower moisture separation element 22a side has a stepped shape. Compared with the high ceiling part 78a, the low ceiling part 78b, which is located far from the lower moisture separation element 22a in the second horizontal direction and is located downward in the vertical direction, the high ceiling part 78a and the low ceiling part 78b And a stepped portion 78c connecting the two. The high ceiling portion 78a and the low ceiling portion 78b extend in the horizontal direction, and the stepped portion 78c extends in the vertical direction.
In some embodiments, as shown in FIGS. 15 to 20, the water seal portion 70 is located below the low ceiling portion 78 b or the drain hole 62.

In some embodiments, as shown in FIG. 18, the drain discharge device 30 f is opposed to the upper end opening of the cup at a distance above the upper end opening of the cup constituting the water seal 70. A shielding plate 80 is further included. The shielding plate 80 has, for example, an annular shape, and is fixed to the internal drain pipe 56 so as to surround the inner drain pipe 56.

In the above configuration, the upper end opening of the cup constituting the water seal portion 70 is completely hidden by the shielding plate 80 when viewed from above. As a result, it is possible to stabilize the water seal by preventing the fluctuation of the water surface caused by the drain dripping from above hitting the water surface of the drain stored in the cup, or to avoid the re-scattering of the drain from the water surface. it can.

In some embodiments, as shown in FIGS. 15 and 17-19, the high ceiling portion 78a has an opening edge 82 at a position corresponding to at least one internal drain pipe 56 in the first horizontal direction. .
In some embodiments, as shown in FIGS. 19 and 20, the drain discharge device 30g further includes at least one baffle plate 84 extending downward from the opening edge 82 of the high ceiling portion 78a. For example, the baffle plates 84 are located on both sides of the internal drain pipe 56, and each baffle plate 84 extends in a plane orthogonal to the first horizontal direction. Each baffle plate 84 closes at least a part of the opening defined by the opening edge 82 of the high ceiling portion 78a.

In the portion where the internal drain pipe 56 passes in the vertical direction, at least the high ceiling portion 78a of the lower drain header portion 52 is interrupted in the first horizontal direction (longitudinal direction). There is a possibility that the drain bounced off from the surface of the drain stored in the cup will flow backward from this interrupted portion. In this regard, in the above configuration, the baffle plate 84 extending downward from the opening edge 82 of the high ceiling portion 78a can prevent the drain bounced off the surface of the drain stored in the cup from flowing back. .

In some embodiments, as shown in FIGS. 8, 9, 14 to 16 and 20, the drain discharge device 30 is connected to a part of the lower drain header portion 52, and the lower drain header portion 52 is connected. And a drain discharge pipe 74 that extends downward from the collection portion 72. The collecting section 72 defines a collecting channel 76 that communicates the lower drain channel 58 and the drain discharge pipe 74, and is collected by the lower moisture separation element 27 a and the upper moisture separation element 27 b through the drain discharge pipe 74. The drain that has been discharged is discharged out of the housing 24.
In the above configuration, since the collecting portion 72 protruding downward from the lower drain header portion 52 is provided, the drain in the lower drain header portion 52 flows into the collecting portion 72. Thereby, it is possible to prevent the drain from being excessively accumulated in the lower drain header portion 52, and the drain in the lower drain header portion 52 can be smoothly discharged.
The volume of the collecting portion 72 is set so that the drain does not accumulate excessively in the lower drain header portion 52 according to the expected drain flow rate.

In some embodiments, the flow area of each drain discharge pipe 74 and the number of drain discharge pipes 74 are set so that self-bending is also realized in the drain discharge pipe 74.
In some embodiments, as shown in FIGS. 8 and 15, the cross-sectional area of the collecting portion 72 is larger than the cross-sectional area of the lower drain header portion 52.
In some embodiments, as shown in FIGS. 8 and 15, the collecting portion 72 protrudes from the lower drain header portion 52 in the second horizontal direction, and in the second horizontal direction, the drain discharge pipe 74 is The internal drain pipe 56 is disposed at a different position.

In some embodiments, as shown in FIGS. 14, 16, and 20, the bottom surface of the lower drain header portion 52 is gradually lowered toward the collecting portion 72 in the axial direction of the housing 24 (first 1 horizontal direction) and extending at an inclination angle θ.
In the above configuration, since the bottom surface of the lower drain header portion 52 is inclined with respect to the first horizontal direction, the drain can be discharged smoothly through the collecting portion 72.

The present invention is not limited to the above-described embodiments, and includes forms obtained by changing the above-described embodiments and forms obtained by combining these forms.

DESCRIPTION OF SYMBOLS 1 Moisture separation heater 2 Secondary steam circulation system 4 Circulation path 6 Steam generator 8 High pressure turbine 10 Low pressure turbine 12 Condenser 14 Deaerator 16 Feed water pump 18 High temperature heater 20 Generator 22 Humidity separation element 22a Lower stage Moisture separation element 22b Upper stage moisture separation element 24 Housing 26 Moisture separation device 28

Heating device

30, 30a-30g Drain discharge device 32 Manifold 34 Steam inlet 36 Steam outlet 38 Steam flow path 40 Lower frame 40a Side wall 42 Upper frame 42a Side wall 44 Corrugated plate 46 Holding member 47 Holding member 48 Heating medium header 50 Heating medium tube 52 Lower drain header portion 52a Lower drain header inlet 54 Upper drain header section 54a Upper drain header outlet 56 Internal drain pipe 58 Lower drain flow path 60 Upper drain flow path 62 Drain hole 64 Drain hole 66 Gas vent hole 68 Gas vent hole 69 Projection 70 Water seal part 72 Collecting part 74 Drain discharge Pipe 76 Collective flow path 78a High ceiling part 78b Low ceiling part 78c Step part 80 Shielding plate 82 Opening edge 84 Baffle plate

Claims

A housing with a steam channel defined therein;
A moisture separator arranged in the steam flow path and capable of separating the moisture from steam containing moisture;
A heating device that is positioned downstream of the moisture separator and disposed in the steam flow path and capable of heating the steam;
A drain discharger capable of discharging the moisture separated by the moisture separator out of the housing;
With
The moisture separator is
A lower moisture separation element extending in a first horizontal direction;
An upper moisture separation element extending in the first horizontal direction and disposed above the lower moisture separation element;
Including
The drain discharge device
A lower drain header portion protruding from the lower moisture separation element in a second horizontal direction orthogonal to the first horizontal direction and extending in the first horizontal direction;
An upper drain header portion protruding from the upper moisture separation element in the second horizontal direction and extending in the first horizontal direction;
At least one internal drain pipe extending in the vertical direction between the upper drain header portion and the lower drain header portion and communicating between the upper drain header portion and the lower drain header portion;
A moisture separator and heater.
In the at least one internal drain pipe, the drain flowing down at least the upper end side of the at least one internal drain pipe flows down in a film shape along the inner peripheral surface of the upper end side of the at least one internal drain pipe. The moisture separator / heater according to claim 1, wherein the moisture separator heater is configured as described above.
The upper drain header portion has an upper drain header outlet that communicates with the internal drain pipe,
The drain discharge device
Two or more pieces positioned on both sides of the upper drain header outlet in the first horizontal direction and disposed on the bottom surface of the upper drain header portion and partially surrounding the upper drain header outlet in the circumferential direction The moisture separation heater according to claim 1, further comprising a protrusion.
The area of the lower drain header inlet that communicates the lower drain header part and the at least one internal drain pipe is the area of the upper drain header outlet that communicates the upper drain header part and the at least one internal drain pipe. The moisture separator / heater according to any one of claims 1 to 3, wherein the moisture separator / heater is smaller.
The moisture separator / heater according to any one of claims 1 to 4, wherein the drain discharge device further includes a water seal portion capable of sealing a lower end portion of the at least one internal drain pipe. .
The water sealing portion is configured by a cup that surrounds a lower end portion of the at least one internal drain pipe and can temporarily store drain that has flowed down in the at least one internal drain pipe.
The ceiling wall of the lower drain header portion has a stepped shape, so that the lower moisture level is higher in the second horizontal direction than the high ceiling portion located on the lower moisture separation element side and the higher ceiling portion. A low ceiling portion located far from the separation element and located below in the vertical direction;
6. The moisture according to claim 5, wherein the drain discharge device further includes a shielding plate disposed above the upper end opening of the cup so as to face the upper end opening of the cup at a distance. Separation heater.
The water sealing portion is configured by a cup that surrounds a lower end portion of the at least one internal drain pipe and can temporarily store drain that has flowed down in the at least one internal drain pipe.
The ceiling wall of the lower drain header portion has a stepped shape, so that the lower moisture level is higher in the second horizontal direction than the high ceiling portion located on the lower moisture separation element side and the higher ceiling portion. A low ceiling portion located far from the separation element and located below in the vertical direction;
At least the high ceiling portion of the ceiling wall has an opening edge at a position corresponding to the at least one internal drain pipe in the first horizontal direction,
The moisture separation heater according to claim 5 or 6, wherein the drain discharge device further includes a baffle plate extending downward from an opening edge of the high ceiling portion.
The drain discharge device
An assembly part connected to a part of the lower drain header part and projecting downward from the lower drain header part,
A drain discharge pipe extending downward from the gathering portion;
The moisture separation heater according to any one of claims 1 to 7, further comprising:
9. The moisture according to claim 8, wherein a bottom surface of the lower drain header portion extends while being inclined with respect to the first horizontal direction so as to be gradually lowered toward the collecting portion. Separation heater.