Technical Field
[0001] The present invention relates to a moisture separating and heating device which produces
superheated vapor by separating moisture from vapor and heating the vapor, and a moisture
separating and heating facility which is provided with the moisture separating and
heating device. This application claims the right of priority based on Japanese Patent
Application No.
2013-006110 filed with the Japan Patent Office on January 17, 2013, the contents of which are
incorporated herein by reference.
Background Art
[0002] In a power-generating plant, there is a case where vapor used in a high-pressure
steam turbine is used again in a low-pressure steam turbine. In this case, if moisture
is present in the vapor, not only are turbine blades of the low-pressure steam turbine
eroded, but also the thermal efficiency of the turbine is reduced. Therefore, in this
case, a moisture separating and heating device which separates moisture from the vapor
discharged from the high-pressure steam turbine and heats the vapor, thereby producing
superheated vapor, is provided between the high-pressure steam turbine and the low-pressure
steam turbine.
[0003] As such a moisture separating and heating device, there is, for example, a moisture
separating and heating device disclosed in PTL 1 below.
[0004] The moisture separating and heating device is provided with a cylindrical container
which extends in a horizontal axial direction and into which vapor to be heated flows,
a partition plate which divides the inside of the container in the axial direction
into an end chamber and a vapor chamber into which the vapor to be heated flows, and
a heater which heats the vapor to be heated having flowed into the vapor chamber with
heating vapor. The heater penetrates through the partition plate and has one portion
located in the vapor chamber and the other portion located in the end chamber.
Citation List
Patent Literature
[0005] [PTL 1] Japanese Unexamined Utility Model Registration Application Publication
63-197903
Summary of Invention
Technical Problem
[0006] In the moisture separating and heating device disclosed in PTL 1 described above,
usually, vapor does not flow into the end chamber. However, a slight amount of vapor
in the vapor chamber flows into the end chamber from a gap between the partition plate
and the heater. The vapor having flowed into the end chamber is condensed and accumulated
in the end chamber as drainage. If the amount of drainage in the end chamber increases,
the heater located in the end chamber and the drainage come into contact with each
other, whereby the heater is cooled, and therefore, the heating efficiency of the
vapor to be heated is reduced. For this reason, it is not preferable that drainage
is accumulated in the end chamber.
[0007] Therefore, a method of providing a separate drain tank having an internal pressure
less than or equal to the pressure in an end chamber and discharging drainage accumulated
in the end chamber into the drain tank is conceivable. However, in this method, it
is necessary to provide a separate drain tank, and thus facility cost increases.
[0008] The present invention provides a moisture separating and heating device in which
it is possible to reduce the amount of drainage which is accumulated in an end chamber
of the moisture separating and heating device, while suppressing an increase in facility
cost, and a moisture separating and heating facility provided with the moisture separating
and heating device.
Solution to Problem
[0009] According to a first aspect of the present invention, there is provided a moisture
separating and heating device including: a cylindrical container which extends in
a horizontal axial direction and in which both ends in the axial direction are sealed
and vapor to be heated flows into the inside; an end partition plate which divides
the inside of the container in the axial direction into an end chamber and a vapor
chamber into which the vapor to be heated flows; and a heater which penetrates through
the end partition plate, has one portion located in the end chamber and the other
portion located in the vapor chamber, and heats the vapor to be heated having flowed
into the vapor chamber with heating vapor. The heater is provided with a vapor drain
pipe which discharges the heating vapor having exchanged heat with the vapor to be
heated and/or drainage of the heating vapor to the outside of the container through
the end chamber. The container is provided with a nozzle which is connected to a high-pressure
fluid supply source for supplying a high-pressure fluid having a pressure higher than
pressure in the end chamber, penetrates into the end chamber from below the end chamber,
and jets the high-pressure fluid into the end chamber.
[0010] In the moisture separating and heating device, even if drainage is accumulated on
the bottom of the end chamber, the drainage is blown off by the high-pressure fluid
which is jetted into the end chamber from below the end chamber. Some of the blown-off
drainage comes into contact with the vapor drain pipe of the heater. In the vapor
drain pipe of the heater, vapor for heating the vapor to be heated which flows into
the vapor chamber or drainage of the heating vapor flows. For this reason, the vapor
drain pipe has a higher temperature than the drainage accumulated on the bottom of
the end chamber. Therefore, the drainage being in contact with the vapor drain pipe
is vaporized, thereby becoming vapor. Some of the vapor flows into the vapor chamber
from, for example, a gap between the container and the end partition plate.
[0011] Therefore, in the moisture separating and heating device, even if drainage is accumulated
on the bottom of the end chamber, it is possible to vaporize the drainage, thereby
making the drainage flow out to the outside of the end chamber. Further, in a steam
plant provided with a moisture separating and heating device, many devices or the
like which retain a high-pressure fluid such as vapor having a pressure higher than
the pressure in an end chamber of the moisture separating and heating device exist.
For this reason, in the moisture separating and heating device, a device or the like
in the steam plant can be easily utilized as a high-pressure fluid supply source.
In addition, it is possible to suppress an increase in facility cost compared with
separately providing a drain tank having an internal pressure less than or equal to
the pressure in the end chamber in order to recover drainage in the end chamber.
[0012] According to a second aspect of the present invention, the moisture separating and
heating device may further include a guide member which guides the high-pressure fluid
such that the high-pressure fluid jetted from the nozzle into the end chamber is directed
to the vapor drain pipe.
[0013] In the heater, the heating vapor having passed through a heat transfer tube and/or
drainage of the heating vapor temporarily stays in a vapor recovery chamber and is
then discharged from the vapor drain pipe to the outside. For this reason, in the
vapor drain pipe of the heater, drainage or the like of the heating vapor flows at
a flow velocity higher than the flow velocity of drainage or the like in the vapor
recovery chamber. Therefore, in the heater, a heat exchange rate between fluids on
the inside and the outside of the vapor drain pipe is higher than a heat exchange
rate between fluids on the inside and the outside of an outer wall of a bonnet or
the like which forms a vapor recovery chamber on the inside thereof.
[0014] In the moisture separating and heating device, the high-pressure fluid jetted from
the nozzle into the end chamber is actively led to the vapor drain pipe of the heater
by the guide member, whereby a contact ratio (the probability of contact) between
the drainage accumulated on the bottom of the end chamber and the vapor drain pipe
is increased. As a result, in the moisture separating and heating device, it is possible
to efficiently vaporize the drainage accumulated on the bottom of the end chamber.
[0015] According to a third aspect of the present invention, the vapor drain pipe may meander
in the end chamber.
[0016] In the moisture separating and heating device, the vapor drain pipe meanders in the
end chamber, and thus a pipe length in the end chamber is long, and therefore, a contact
ratio of blown-off drainage with respect to the vapor drain pipe increases.
[0017] According to a fourth aspect of the present invention, there is provided a moisture
separating and heating facility including: the moisture separating and heating device
according to any one of the above aspects; a drain tank as the high-pressure fluid
supply source, which receives drainage accumulated at a lower portion in the vapor
chamber of the moisture separating and heating device; and a high-pressure fluid line
which connects an upper portion of the drain tank and the nozzle and supplies vapor
in the drain tank to the nozzle as the high-pressure fluid.
[0018] In a case where a moisture separating and heating device is installed, a drain tank
which receives drainage from the moisture separating and heating device is also installed
in conjunction with the installation. In the moisture separating and heating facility,
the drain tank is utilized as a high-pressure fluid supply source, and therefore,
it is possible to suppress an increase in facility cost.
[0019] Here, in the moisture separating and heating facility, the high-pressure fluid line
may be provided with a flow rate regulating valve which regulates the flow rate of
the vapor which is supplied from the drain tank to the end chamber through the nozzle.
[0020] In the moisture separating and heating facility, it is possible to regulate the flow
rate of vapor which is supplied from the drain tank to the end chamber through the
nozzle.
Advantageous Effects of Invention
[0021] According to the above aspects, it is possible to reduce the amount of drainage which
is accumulated in the end chamber of the moisture separating and heating device, while
suppressing an increase in facility cost. Brief Description of Drawings
[0022]
Fig. 1 is a perspective view, with a main section cut away, of a moisture separating
and heating device in an embodiment related to the present invention.
Fig. 2 is a vertical cross-sectional view of the moisture separating and heating device
in the embodiment related to the present invention.
Fig. 3 is a cross-sectional view taken along line III-III in Fig. 2.
Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 3.
Fig. 5 is a cross-sectional view taken along line V-V in Fig. 2.
Fig. 6 is an enlarged perspective view, with a main section cut away, of the moisture
separating and heating device in the embodiment related to the present invention.
Fig. 7 is a vertical cross-sectional view of main sections of the moisture separating
and heating device and a drain tank in the embodiment related to the present invention.
Fig. 8 is a system diagram of a steam plant in the embodiment related to the present
invention.
Fig. 9 is a vertical cross-sectional view of main sections of a moisture separating
and heating device and a drain tank in a modified example of the embodiment related
to the present invention.
Description of Embodiments
[0023] Hereinafter, an embodiment and a modified example of a moisture separating and heating
facility according to the present invention will be described in detail with reference
to the drawings.
[Embodiment of Moisture Separating and Heating Facility]
[0024] First, an embodiment of a moisture separating and heating facility according to the
present invention will be described by using Figs. 1 to 8.
[0025] The moisture separating and heating facility of this embodiment configures a portion
of a steam plant, as shown in Fig. 8. The steam plant is provided with a BWR (Boiling
Water Reactor) type reactor pressure vessel 1, a reactor containment vessel 2 covering
the reactor pressure vessel 1, a high-pressure steam turbine 3 which is driven by
steam generated in the reactor pressure vessel 1, a moisture separating and heating
facility 4 which separates moisture from vapor exhausted from the high-pressure steam
turbine 3 and heats the vapor, a low-pressure steam turbine 5 which is driven by the
vapor from the moisture separating and heating facility 4, a power generator 6 which
generates electric power with the driving of the high-pressure steam turbine 3 and
the low-pressure steam turbine 5, a condenser 7 which returns the vapor exhausted
from the low-pressure steam turbine 5 to water, and a water feed pump 8 which sends
the water in the condenser 7 to the reactor pressure vessel 1.
[0026] The moisture separating and heating facility 4 is provided with a moisture separating
and heating device M which separates moisture from the vapor exhausted from the high-pressure
steam turbine 3 and heats the vapor, and a drain tank T which receives drainage accumulated
in the moisture separating and heating device M.
[0027] The moisture separating and heating device M is provided with a cylindrical container
10 into which vapor to be heated S enters, and a heater 55 which heats the vapor to
be heated S having entered into the container 10, as shown in Figs. 1 to 5. In addition,
Fig. 3 is a cross-sectional view taken along line III-III in Fig. 2. Fig. 4 is a cross-sectional
view taken along line IV-IV in Fig. 3. Fig. 5 is a cross-sectional view taken along
line V-V in Fig. 2.
[0028] The container 10 has a cylindrical shell 15 which extends in a horizontal axial direction
H, and end plates 16 which block ends in the axial direction H of the shell 15. The
inside of the container 10 is divided into an end chamber 62 and a vapor chamber 20
in the axial direction H by an end partition plate 60. In addition, in the following,
a direction which is a horizontal direction and is perpendicular to the axial direction
H is referred to as a transverse width direction W.
[0029] In the container 10, there are formed a vapor inlet 11 through which the vapor to
be heated S is received into the vapor chamber 20, a plurality of vapor outlets 12
which send out superheated vapor HS subjected to moisture separation and heated in
the vapor chamber 20, and a plurality of vapor drainage outlets 13 which discharge
vapor drainage D from the vapor chamber 20. The vapor inlet 11 is formed at a lower
portion of the container 10 and at a central portion of the container 10 in the axial
direction H. Further, the plurality of vapor drainage outlets 13 are formed at the
lower portion of the container 10 and on both sides in the axial direction H on the
basis of the vapor inlet 11. The plurality of vapor outlets 12 are formed side by
side in the axial direction H at an upper portion of the container 10. In addition,
one vapor outlet 12 among the plurality of vapor outlets 12 is formed at the central
portion of the container 10 in the axial direction H, similarly to the vapor inlet
11.
[0030] In the vapor chamber 20, there are formed a vapor receiving chamber 21 into which
the vapor to be heated S flowing in from the vapor inlet 11 enters, a supply manifold
chamber 22 (refer to Figs. 4 and 5) which communicates with the vapor receiving chamber
21 and is adjacent to both sides of the vapor receiving chamber 21 in the axial direction
H, a moisture separation chamber 23 (refer to Figs. 4 and 5) which communicates with
the supply manifold chamber 22 and is adjacent to the lower side of the supply manifold
chamber 22, a heating chamber 24 which communicates with the moisture separation chamber
23 and in which the heater 55 is accommodated, a vapor drainage recovery chamber 25
(refer to Figs. 4 and 5) which communicates with the moisture separation chamber 23
and is adjacent to the lower sides of the moisture separation chamber 23 and the heating
chamber 24, and a vapor recovery manifold chamber 26 which communicates with the heating
chamber 24 and the vapor outlets 12 and is adjacent to the upper sides of the vapor
receiving chamber 21, the supply manifold chamber 22, and the heating chamber 24.
[0031] The vapor recovery manifold chamber 26 is formed at an upper portion in the vapor
chamber 20 over almost the whole of the vapor chamber 20 in the axial direction H,
as shown in Figs. 1 and 2. On the other hand, the vapor receiving chamber 21 is formed
adjacent to the lower side of the vapor recovery manifold chamber 26 at a central
portion in the axial direction H of the vapor chamber 20. The vapor recovery manifold
chamber 26 and the vapor receiving chamber 21 are separated from each other by a ceiling
plate 30, as shown in Figs. 3 and 6.
[0032] All of the supply manifold chamber 22, the moisture separation chamber 23, the heating
chamber 24, and the vapor drainage recovery chamber 25 are adjacent to both sides
of the vapor receiving chamber 21 in the axial direction H, as shown in Figs. 1, 2,
and 4. As shown in Figs. 2 and 5, the heating chamber 24 is formed at the center in
the transverse width direction W at a position deviated from the vapor receiving chamber
21 in the axial direction H. Further, the supply manifold chamber 22 is formed on
both sides of the heating chamber 24 in the transverse width direction W, and the
moisture separation chamber 23 is formed on both sides of the heating chamber 24 in
the transverse width direction W and on the lower side of the supply manifold chamber
22. The vapor recovery manifold chamber 26 is formed on the upper sides of the vapor
receiving chamber 21, the heating chamber 24, and the supply manifold chamber 22.
Further, the vapor drainage recovery chamber 25 is formed on the lower sides of the
heating chamber 24 and the moisture separation chamber 23 at a position deviated from
the vapor receiving chamber 21 in the axial direction H.
[0033] The moisture separation chamber 23, the heating chamber 24, and the vapor drainage
recovery chamber 25 among the supply manifold chamber 22, the moisture separation
chamber 23, the heating chamber 24, and the vapor drainage recovery chamber 25 which
are adjacent to the vapor receiving chamber 21 in the axial direction H are separated
from the vapor receiving chamber 21 by a transverse partition plate 33, as shown in
Figs. 1 to 3 and 6. In addition, the supply manifold chamber 22 is open without being
separated from the vapor receiving chamber 21 by the transverse partition plate 33
in order to communicate with the vapor receiving chamber 21.
[0034] The supply manifold chamber 22 is separated from the vapor recovery manifold chamber
26 adjacent to the upper side of the supply manifold chamber 22 by inclined plates
35, as shown in Figs. 5 and 6. Each of the inclined plates 35 gradually slopes upward
with increasing distance from the central portion of the container 10 in the transverse
width direction W, and an end portion farthest from the central portion is joined
to the inner surface of the container 10.
[0035] The moisture separation chamber 23 is separated from the supply manifold chamber
22 adjacent to the upper side of the moisture separation chamber 23 by distribution
plates 36, as shown in Figs. 4 and 5. In the distribution plate 36, a plurality of
slits 37 which penetrate in an up-down direction V and are long in the transverse
width direction W are formed. The vapor drainage recovery chamber 25 is separated
from the heating chamber 24 and the moisture separation chamber 23 adjacent to the
upper side of the vapor drainage recovery chamber 25 by a bottom plate 38. The heating
chamber 24 is separated from the supply manifold chamber 22 and the moisture separation
chamber 23 adjacent to both sides of the heating chamber 24 in the transverse width
direction W by longitudinal partition plates 43. An end edge in the axial direction
H of the ceiling plate 30 which separates the vapor recovery manifold chamber 26 and
the vapor receiving chamber 21 from each other is joined to an upper end 43u of the
longitudinal partition plate 43, as shown in Fig. 6. In addition, a center-side end
portion of each of the inclined plates 35 which separate the supply manifold chamber
22 and the vapor recovery manifold chamber 26 from each other is joined to the upper
end 43u of the longitudinal partition plate 43, as shown in Figs. 5 and 6. Further,
a center-side end portion of each of the distribution plates 36 which separate the
moisture separation chamber 23 and the supply manifold chamber 22 from each other
is joined to a central portion in the up-down direction V of the longitudinal partition
plate 43.
[0036] All of end portions on the side opposite to the vapor receiving chamber 21 in the
axial direction H, in the vapor recovery manifold chamber 26, the supply manifold
chamber 22, the moisture separation chamber 23, the heating chamber 24, and the vapor
drainage recovery chamber 25 which are shown in Fig. 5, are blocked with the end partition
plate 60, as shown in Figs. 1 and 2. For this reason, all of ends in the axial direction
H of the inclined plate 35 which separates the supply manifold chamber 22 and the
vapor recovery manifold chamber 26 from each other, the distribution plate 36 disposed
between the moisture separation chamber 23 and the supply manifold chamber 22, the
longitudinal partition plate 43 which separates the supply manifold chamber 22 and
the moisture separation chamber 23 from the heating chamber 24, and the bottom plate
38 disposed between the heating chamber 24 and the moisture separation chamber 23,
and the vapor drainage recovery chamber 25 are joined to the end partition plate 60.
In addition, in an upper end of the end partition plate 60, as shown in Fig. 7, an
air vent hole 61 making the vapor recovery manifold chamber 26 and the end chamber
62 communicate with each other, thereby extracting air in the vapor chamber 20, is
formed.
[0037] In the vapor receiving chamber 21, as shown in Figs. 1 to 3 and 6, a baffle plate
50 in which a cross-sectional shape perpendicular to the axial direction H is a U-shape
and a portion equivalent to a curved portion of the U-shape faces the lower side is
disposed.
[0038] Mist separators 53 are disposed in the moisture separation chamber 23, as shown in
Figs. 4 and 5. The mist separator 53 is made by disposing a plurality of corrugated
plates (not shown) at equal intervals in the axial direction H and has a baffle (not
shown) provided to face the flow of the vapor to be heated S at the top of each of
the corrugated plates. All of the tops and the bottoms of the plurality of corrugated
plates extend in the up-down direction V. In the bottom plate 38 separating the moisture
separation chamber 23 and the vapor drainage recovery chamber 25 from each other,
openings 39 penetrating in the up-down direction V at positions equivalent to lower
portions of the plurality of corrugated plates configuring the mist separator 53 are
formed.
[0039] The heater 55 includes a first heater 55A disposed on the lower side in the container
10, and a second heater 55B disposed on the upper side in the container 10, as shown
in Figs. 1 to 3.
[0040] Each of the first heater 55A and the second heater 55B has a heat transfer tube 56
formed with a U-shaped tube, a tube plate 57 to which an end portion of the heat transfer
tube 56 is fixed, a bonnet 58 covering the side opposite to the side from which the
heat transfer tube 56 extends, of the tube plate 57, and a partition plate 59 dividing
a space which is formed by the tube plate 57 and the inner surface of the bonnet 58,
into an upper space and a lower space. In the heat transfer tube 56 which is a U-shaped
tube, an end portion 56a on the curved side faces the central portion side in the
axial direction H of the container 10 and a tube end 56b of the heat transfer tube
56 faces the end portion side in the axial direction H of the container 10. In the
space which is formed by the tube plate 57 and the inner surface of the bonnet 58,
the space above the partition plate 59 forms a vapor receiving chamber 59a and the
space below the partition plate 59 forms a vapor recovery chamber 59b. A vapor supply
pipe 58i for supplying heating vapor to the vapor receiving chamber 59a and a vapor
drain pipe 58o for discharging the heating vapor and/or drainage of the heating vapor
in the vapor recovery chamber 59b to the outside are connected to the bonnet 58.
[0041] First heating vapor S1 is supplied from the outside to the heat transfer tube 56
of the first heater 55A through the vapor supply pipe 58i and the vapor receiving
chamber 59a. Further, second heating vapor S2 is supplied to the heat transfer tube
56 of the second heater 55B through the vapor supply pipe 58i and the vapor receiving
chamber 59a.
[0042] In addition, the first heating vapor S1 is vapor having a temperature higher than
the temperature of the vapor to be heated S flowing from the high-pressure steam turbine
3 (refer to Fig. 8) into the vapor receiving chamber 21 of the moisture separating
and heating device M. Further, the second heating vapor S2 is vapor having a temperature
higher than the temperature of the first heating vapor S1.
[0043] The bonnet 58 of the first heater 55A is disposed in the end chamber 62, and the
heat transfer tube 56 of the first heater 55A penetrates through the end partition
plate 60 and is located in the heating chamber 24. Further, the bonnet 58 of the second
heater 55B is disposed outside the container 10, and the heat transfer tube 56 of
the second heater 55B penetrates through the end plate 16 of the container 10 and
the end partition plate 60 and is located in the end chamber 62 and the heating chamber
24. As shown in Fig. 6, the end portion 56a on the curved side of the heat transfer
tube 56 in each of the first heater 55A and the second heater 55B penetrates through
the transverse partition plate 33 in the axial direction H, is located further toward
the central portion side in the axial direction H of the container 10 than the end
portions in the axial direction H of the transverse partition plate 33 and the ceiling
plate 30, and is covered with a shroud 44.
[0044] In the end plate 16 of the container 10, as shown in Figs. 1 and 7, a nozzle 63 penetrating
from below the end plate 16 into the end chamber 62 and jetting spraying vapor S3
into the end chamber 62 is provided.
[0045] In an upper portion of the drain tank T, as shown in Fig. 7, a drainage receiving
port 71 which receives the vapor drainage D accumulated in the vapor drainage recovery
chamber 25 of the moisture separating and heating device M, and a vapor outlet 72
which discharges vapor in the drain tank T are formed. Further, in a lower portion
of the drain tank T, a drainage outlet 73 which discharges the vapor drainage D in
the drain tank T is formed.
[0046] The vapor outlet 72 of the drain tank T and the nozzle 63 of the moisture separating
and heating device M are connected by a spraying vapor line (a high-pressure fluid
line) 75 in order to supply vapor staying in an upper portion in the drain tank T
into the end chamber 62 as the spraying vapor S3. In the spraying vapor line 75, a
flow rate regulating valve 76 which regulates the flow rate of the spraying vapor
S3 passing through the spraying vapor line 75 is provided.
[0047] Next, the flow of vapor and drainage in the moisture separating and heating facility
4 described above will be described.
[0048] As shown in Figs. 1 to 3 and 6, if the vapor to be heated S used in the high-pressure
steam turbine 3 (refer to Fig. 8) flows from the vapor inlet 11 into the vapor receiving
chamber 21, the vapor to be heated S is guided to the upper side and to both sides
in the transverse width direction W while an impact at the time of inflow into the
vapor receiving chamber 21 is alleviated at the baffle plate 50, thereby flowing into
the supply manifold chamber 22.
[0049] The vapor to be heated S having flowed into the supply manifold chamber 22 flows
into the moisture separation chamber 23 through the slits 37 of the distribution plates
36, as shown in Figs. 4 and 5. In the moisture separation chamber 23, the vapor to
be heated S comes into contact with the plurality of corrugated plates, the baffles,
and the like configuring the mist separator 53, whereby moisture in the vapor to be
heated S is captured by the plurality of corrugated plates and the baffles, then flows
down to the lower side, and flows from the openings 39 of the bottom plate 38 into
the vapor drainage recovery chamber 25. The moisture, that is, the vapor drainage
D, which has flowed into the vapor drainage recovery chamber 25, flows out from the
vapor drainage outlet 13 along with some of the vapor to be heated S and flows into
the drain tank T.
[0050] On the other hand, the vapor to be heated S having passed through the mist separators
53 flows into the heating chamber 24 and is heated by the first heater 55A and the
second heater 55B in the process of flowing upward through the heating chamber 24,
thereby becoming the superheated vapor HS. The superheated vapor HS flows from the
heating chamber 24 into the vapor recovery manifold chamber 26 and then flows out
from the vapor outlet 12 to the outside. The superheated vapor HS having flowed out
from the moisture separating and heating device M is sent to the low-pressure steam
turbine 5 (refer to Fig. 8).
[0051] The vapor drainage D and some of the vapor to be heated S having flowed into the
drain tank T are divided into a gas phase and a liquid phase and temporarily accumulated
in the drain tank T, as shown in Fig. 7. Pressure P4 in the drain tank T is almost
the same as pressures P1 and P2 in the drainage recovery chamber and the heating chamber
of the moisture separating and heating device M. On the other hand, pressure P3 in
the end chamber 62 of the moisture separating and heating device M is lower than the
pressures P1 and P2 in the vapor drainage recovery chamber 25 and the heating chamber
24, and therefore, the pressure is also lower than the pressure P4 in the drain tank
T. For this reason, a gas phase fluid (a high-pressure fluid), that is, the spraying
vapor S3, staying at the upper portion in the drain tank T is jetted into the end
chamber 62 of the moisture separating and heating device M from below the end chamber
62 through the vapor outlet 72 formed at the upper portion of the drain tank T, the
spraying vapor line (the high-pressure fluid line) 75, and the nozzle 63 of the moisture
separating and heating device M.
[0052] Incidentally, in a case where the nozzle 63 is not provided, the end chamber 62 does
not form a portion of a pathway through which vapor flows, and therefore, usually,
vapor does not flow into the end chamber 62. However, as described above, the pressures
P1 and P2 in the heating chamber 24 are higher than the pressure P3 in the end chamber
62, and therefore, the vapor to be heated S in the heating chamber 24 flows in from
gaps between the end partition plate 60 and the heat transfer tubes 56 of the first
and second heaters 55A and 55B. In particular, the vapor to be heated S in the heating
chamber 24 flows in from the gap between the end partition plate 60 and the heat transfer
tube 56 of the first heater 55A. This is because the pressure P1 of the vapor to be
heated S around the heat transfer tube 56 of the first heater 55A is slightly higher
than the pressure P2 of the vapor to be heated around the heat transfer tube 56 of
the second heater 55B because the first heater 55A is located further toward the upstream
side than the second heater 55B for the vapor to be heated S.
[0053] The vapor having flowed from the heating chamber 24 into the end chamber 62 is condensed
and accumulated in the end chamber 62 as drainage. If the amount of drainage in the
end chamber 62 increases and thus a drainage level in the end chamber 62 becomes higher,
the upper portion or the vapor supply pipe 58i of the bonnet 58 of the first heater
55A located in the end chamber 62 comes into contact with the drainage. As a result,
the first heating vapor S1 flowing through the vapor supply pipe 58i or the vapor
receiving chamber 59a of the first heater 55A is cooled, and thus the heating efficiency
of the vapor to be heated S is reduced.
[0054] For this reason, it is not preferable that drainage is accumulated in the end chamber
62.
[0055] In this embodiment, if the flow rate regulating valve 76 in the spraying vapor line
75 is opened, the vapor in the drain tank T is jetted into the end chamber 62 as the
spraying vapor S3, and therefore, the pressure in the end chamber 62 is increased,
and thus the amount of the vapor to be heated S in the heating chamber 24 which flows
into the end chamber 62 from the gaps between the end partition plate 60 and the heat
transfer tubes 56 of the first and second heaters 55A and 55B is reduced.
[0056] Further, even if drainage is accumulated on the bottom of the end chamber 62, the
drainage is blown off by the spraying vapor S3 which is jetted into the end chamber
62 from below the end chamber 62, and some of the blown-off drainage comes into contact
with the lower surface or the vapor drain pipe 58o of the bonnet 58 of the first heater
55A. Furthermore, the vapor drain pipe 58o meanders in the end chamber 62, as shown
in Figs. 1 and 7, and thus the pipe length in the end chamber 62 is long, and therefore,
the contact ratio of the blown-off drainage with respect to the vapor drain pipe 58o
is increased. In the bonnet 58 or the vapor drain pipe 58o of the first heater 55A,
the high-temperature first heating vapor S1 supplied to the heat transfer tube 56
of the first heater 55A or drainage of the first heating vapor flows, and therefore,
the lower surface or the vapor drain pipe 58o of the bonnet 58 of the first heater
55A has a higher temperature than the drainage accumulated on the bottom of the end
chamber 62. For this reason, the drainage which is in contact with the lower surface
or the vapor drain pipe 58o of the bonnet 58 of the first heater 55A is vaporized,
thereby becoming vapor. Some of the vapor flows from, for example, the gap between
the end partition plate 60 and the heat transfer tube 56 of the second heater 55B
into the heating chamber 24 and some other vapor flows from the air vent hole 61 of
the end partition plate 60 into the vapor recovery manifold chamber 26 having even
lower pressure than the heating chamber 24.
[0057] Therefore, in this embodiment, even if drainage is accumulated on the bottom of the
end chamber 62, it is possible to vaporize the drainage, thereby causing the drainage
to flow out to the outside of the end chamber 62.
[0058] Accordingly, in this embodiment, it is possible to reduce the amount of drainage
which is accumulated in the end chamber 62 of the moisture separating and heating
device M. Furthermore, in a case where the moisture separating and heating device
M is installed, the drain tank T which is installed in conjunction with the installation
is used as a supply source of a high-pressure fluid for blowing off the drainage accumulated
in the end chamber 62, and therefore, it is possible to suppress an increase in facility
cost.
[0059] In addition, the flow rate regulating valve 76 in the spraying vapor line 75 may
be opened at all times, but may be made so as to be periodically and temporarily opened.
[Modified Example of Moisture Separating and Heating Device]
[0060] Next, a modified example of the moisture separating and heating device described
above will be described by using Fig. 9.
[0061] The moisture separating and heating device M of this modified example is provided
with a guide member 65 for actively leading the spraying vapor S3 jetted from the
nozzle 63 into the end chamber 62 to the vapor drain pipe 58o of the first heater
55A.
[0062] In a case where the guide member 65 is not provided, as described above, the drainage
accumulated on the bottom of the end chamber 62 comes into contact with the lower
surface or the vapor drain pipe 58o of the bonnet 58 of the first heater 55A due to
the spraying vapor S3 jetted from the nozzle 63 into the end chamber 62. The first
heating vapor S1 supplied to the heat transfer tube 56 of the first heater 55A and/or
drainage of the first heating vapor temporarily stays in the vapor recovery chamber
59b in the bonnet 58 of the first heater 55A. On the other hand, in the vapor drain
pipe 58o of the first heater 55A, the first heating vapor S1 and/or drainage of the
first heating vapor flows at a higher flow velocity than the flow velocity of drainage
in the vapor recovery chamber 59b. Therefore, a heat exchange rate between fluids
on the inside and the outside of the vapor drain pipe 58o is higher than a heat exchange
rate between fluids on the inside and the outside of the bonnet 58.
[0063] Therefore, in this modified example, the spraying vapor S3 jetted from the nozzle
63 into the end chamber 62 is actively led to the vapor drain pipe 58o of the first
heater 55A by the guide member 65, whereby a contact ratio between the drainage accumulated
on the bottom of the end chamber 62 and the vapor drain pipe 58o is increased. As
a result, in this modified example, it is possible to efficiently vaporize the drainage
accumulated on the bottom of the end chamber 62.
[0064] In addition, in the embodiment and the modified example described above, the drain
tank T of the moisture separating and heating device M is used as a high-pressure
fluid supply source and the spraying vapor S3 in the drain tank T is jetted to the
end chamber 62 of the moisture separating and heating device M as a high-pressure
fluid. However, vapor from another high-pressure fluid supply source in the steam
plant may be jetted to the end chamber 62 of the moisture separating and heating device
M as a high-pressure fluid. Even with such a configuration, since many devices or
the like which retain vapor having a pressure higher than the pressure in the end
chamber 62 of the moisture separating and heating device M exist in the steam plant,
it is possible to suppress an increase in facility cost compared with separately providing
a drain tank having an internal pressure less than or equal to the pressure in the
end chamber 62.
Industrial Applicability
[0065] According to the moisture separating and heating device and the moisture separating
and heating facility, it is possible to reduce the amount of drainage which is accumulated
in the end chamber of the moisture separating and heating device, while suppressing
an increase in facility cost.
Reference Signs List
[0066]
- 3:
- high-pressure steam turbine
- 4:
- moisture separating and heating facility
- 5:
- low-pressure steam turbine
- 10:
- container
- 11:
- vapor inlet
- 12:
- vapor outlet
- 15:
- shell
- 16:
- end plate
- 20:
- vapor chamber
- 21:
- vapor receiving chamber
- 22:
- supply manifold chamber
- 23:
- moisture separation chamber
- 24:
- heating chamber
- 25:
- vapor drainage recovery chamber
- 26:
- vapor recovery manifold chamber
- 30:
- ceiling plate
- 33:
- transverse partition plate
- 35:
- inclined plate
- 36:
- distribution plate
- 38:
- bottom plate
- 43:
- longitudinal partition plate
- 44:
- shroud
- 50:
- baffle plate
- 53:
- mist separator
- 55:
- heater
- 55A:
- first heater
- 55B:
- second heater
- 56:
- heat transfer tube
- 58:
- bonnet
- 58i:
- vapor supply pipe
- 58o:
- vapor drain pipe
- 59:
- partition plate
- 59a:
- vapor receiving chamber
- 59b:
- vapor recovery chamber
- 60:
- end partition plate (or partition plate)
- 61:
- air vent hole
- 62:
- end chamber
- 63:
- nozzle
- 65:
- guide member
- 75:
- spraying vapor line (high-pressure fluid line)
- 76:
- flow rate regulating valve
- M:
- moisture separating and heating device
- T:
- drain tank (high-pressure fluid supply source)
- S:
- vapor to be heated
- HS:
- superheated vapor
- S1:
- first heating vapor
- S2:
- second heating vapor
- S3:
- spraying vapor (high-pressure fluid)