U.S. patent application number 15/503702 was filed with the patent office on 2017-09-28 for condenser for a steam power plant.
This patent application is currently assigned to Siemens Aktiengesellschaft. The applicant listed for this patent is Siemens Aktiengesellschaft. Invention is credited to Kai Brune, Stefan Brussk, Nigel-Philip Cox, Daniel Dreier, Tobias Gabl-Zimmek, Andrei Ghicov, Marie Hu, Mario Koebe, Marc Lange, Teresa Pott, Stefan Riemann, Andreas Ulma, David Veltmann, Gerta Zimmer.
Application Number | 20170276432 15/503702 |
Document ID | / |
Family ID | 51383597 |
Filed Date | 2017-09-28 |
United States Patent
Application |
20170276432 |
Kind Code |
A1 |
Brune; Kai ; et al. |
September 28, 2017 |
CONDENSER FOR A STEAM POWER PLANT
Abstract
A method for operating a condenser, wherein the condenser is
designed for condensing water vapor to form water and during
operation a condensate having water accumulates in the condenser,
wherein on the condensate surface a plurality of floating bodies
are arranged on the condensate, wherein the floating bodies float
on the condensate, wherein a large number of floating bodies are
used in such a way that the condensate surface is covered, wherein
the floating bodies are of spherical and/or sphere-like design, and
wherein floating bodies with different sizes are used.
Inventors: |
Brune; Kai; (Rheinberg,
DE) ; Brussk; Stefan; (Mulheim an der Ruhr, DE)
; Cox; Nigel-Philip; (Mulheim an der Ruhr, DE) ;
Dreier; Daniel; (Essen, DE) ; Gabl-Zimmek;
Tobias; (Essen, DE) ; Ghicov; Andrei; (Mulheim
an der Ruhr, DE) ; Hu; Marie; (Mulheim an der Ruhr,
DE) ; Koebe; Mario; (Mulheim an der Ruhr, DE)
; Lange; Marc; (Koln, DE) ; Pott; Teresa;
(Essen, DE) ; Riemann; Stefan; (Kaarst, DE)
; Ulma; Andreas; (Mulheim an der Ruhr, DE) ;
Veltmann; David; (Essen, DE) ; Zimmer; Gerta;
(Mulheim an der Ruhr, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Siemens Aktiengesellschaft |
Munich |
|
DE |
|
|
Assignee: |
Siemens Aktiengesellschaft
Munich
DE
|
Family ID: |
51383597 |
Appl. No.: |
15/503702 |
Filed: |
August 19, 2015 |
PCT Filed: |
August 19, 2015 |
PCT NO: |
PCT/EP2015/069010 |
371 Date: |
February 13, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F28B 9/08 20130101; F01K
11/00 20130101; F28B 9/00 20130101; F01K 9/00 20130101; F28F 19/002
20130101 |
International
Class: |
F28B 9/00 20060101
F28B009/00; F28F 19/00 20060101 F28F019/00; F28B 9/08 20060101
F28B009/08 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 20, 2014 |
EP |
14181545.6 |
Claims
1.-8. (canceled)
9. A method for operating a condenser, wherein the condenser is
designed for condensing water vapor to form water and during
operation a condensate consisting of water accumulates in the
condenser, the method comprising: arranging on the condensate
surface a plurality of floating bodies on the condensate, wherein
the floating bodies float on the condensate, wherein a large number
of floating bodies are used such that the condensate surface is
covered, wherein the floating bodies are of spherical and/or
sphere-like design, and wherein floating bodies with different
sizes are used.
10. The method as claimed in claim 9, wherein floating bodies with
different shapes are used.
11. The method as claimed in claim 9, wherein a large number of
floating bodies are arranged in the condenser such that they lie
one above the other.
12. The method as claimed in claim 9, wherein floating bodies with
different densities are used.
13. Floating bodies for floating on a condensate in a condenser,
comprising: floating bodies designed for the method as claimed in
claim 9.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is the US National Stage of International
Application No. PCT/EP2015/069010 filed Aug. 19, 2015, and claims
the benefit thereof. The International Application claims the
benefit of European Application No. EP14181545 filed Aug. 20, 2014.
All of the applications are incorporated by reference herein in
their entirety.
FIELD OF INVENTION
[0002] The invention relates to a method for operating a
condenser.
BACKGROUND OF INVENTION
[0003] Modern power plants as a rule comprise a gas and steam
turbine plant and electric generators which are designed for
generating electric energy. The torque-transmitting drive for the
electric generators is carried out via the shafts of the gas
turbine and/or steam turbine.
[0004] During operation, steam, which is produced in a steam
generator, flows to a high-pressure turbine section and from there
to a reheater in which the steam is brought up to a certain
temperature. After the reheating, the steam flows to an
intermediate-pressure turbine section and from there flows via a
crossover pipe to a low-pressure turbine section. Downstream of the
low-pressure turbine section, the steam flows into a condenser and
condenses there to form water. In the condenser, the water is
collected to form a condensate. The condensate has a condensate
surface which in the main is fluidically connected to the flow
passage of the steam turbine. Therefore, an evaporating condensate
is connected to the fact that via the fluidic connection a certain
proportion of water vapor from the condensate flows back into the
steam turbine.
[0005] The current market requirements lead to the power plant
operators having to put their power plants into more frequent,
unscheduled shutdown states of unforeseeable duration. This means,
however, that after the shutting down of a steam turbine the steam
which is present in the steam turbine condenses as soon as the
temperature falls below the dew point. As a rule, the seal steam
system is no longer in operation after such a shutdown. The
combination with the water which is available from the condenser,
with the oxygen which is provided by means of the vacuum breaker
and the shaft bushing, and with the metal, leads to a possible
occurrence of corrosion. Therefore, in the case of a stationary
steam turboset the risk of stagnant-condition corrosion inside the
turbine casing, valve housings and condensers may exist as soon as
the relative air moisture of the ambient air inside the respective
components exceeds a limit value or the surface temperature of the
metal parts inside the turbine and valve housings and also
condensers cools down in such a way that the metal parts can fall
below the dew point temperature.
[0006] In particular, the final stages of low-pressure turbine
sections and the condenser are at risk of corrosion since even
during operation their temperatures lie close to the dew point or
already lie below it.
[0007] In order to be able to put the steam power plant quickly
into operation again and in order to minimize the operating costs,
the condensate in the hotwell in the condenser is not released and
remains inside the condenser. This, however, results in the
evaporation leading to an increase of the moisture in the condenser
and in the low-pressure turbine section adjoining it.
[0008] In order to avoid corrosion, provision is made for
installing dry-air equipment after the first day of the shutdown.
As a result of the operation using dry-air equipment, dried air
from the environment is continuously introduced into the turbine
casing and therefore the entry of moist ambient air from the
turbine hall is prevented. The introduced dry air absorbs moisture
from the inside of the turbine casing and valve housings and also
from the condensers and is discharged again at defined
openings.
SUMMARY OF INVENTION
[0009] The invention has set itself an object of specifying another
way of effectively preventing corrosion in the steam turbine after
a shutdown.
[0010] This object is achieved by means of a method for operating a
condenser as claimed.
[0011] The evaporation of the condensate is directly dependent on
the size of the contact area between water and air. With the
invention, the size of the contact area is effectively reduced by
floating bodies being arranged on the condensate. The contact area
is reduced as a result of the floating bodies. Consequently, the
evaporation in the hotwell is also reduced. A lower moisture
content is achieved and the risk of local moisture points is
especially reduced.
[0012] Furthermore, a lower volumetric flow of dry air is required,
which leads to a lowering of operating costs during the drying. By
means of the invention, the drying of the turbine is therefore
effectively supported.
[0013] The floating bodies are arranged according to the invention
in a sufficiently large number in a floating manner on the
condensate surface.
[0014] Advantageous developments are disclosed in the dependent
claims.
[0015] The floating bodies are advantageously of spherical and/or
sphere-like design. In this case, shapes such as a strict spherical
shape can feature, i.e. the floating body is a sphere with a
determined radius. As opposed to this spherical shape, the floating
body can also be of sphere-like design, e.g. ellipsoidal.
[0016] The floating bodies advantageously have different sizes.
Therefore, the condensate surface can be still further effectively
reduced since the points between the large floating bodies can be
closed off by smaller floating bodies.
[0017] Furthermore, in an advantageous embodiment the floating
bodies are designed and arranged in such a way that the floating
bodies have different shapes. So, in addition to a spherical
floating body, sphere-like floating bodies can therefore also be
arranged next to each other on the condensate surface. As a result,
the condensate surface is likewise effectively reduced.
[0018] In a further advantageous development, the floating bodies
are designed in such a way that rotation of the floating body is
prevented. Due to the impeded rotation of the floating body, it is
possible that the same surface always points to the condensate
surface and the non-wetted surface points opposite to the
condensate surface. As a result, the non-wetted surface remains
dry. An increase of the air humidity is prevented as a
consequence.
[0019] In an advantageous development, the floating bodies have
different densities. This leads to the floating bodies being able
to be arranged in different layers on the condensate surface. The
floating bodies in an advantageous development are provided with a
material surface which is as hydrophobic as possible. A hydrophobic
surface results in a non-wettable surface. Therefore, the moisture
is retained in the condensate.
[0020] A further advantage of the invention is that existing
condenser plants can be retrofitted without restriction in a very
simple and inexpensive manner according to the invention. Since an
adaptation to the specific condenser geometry is carried out
exclusively via the quantity of floating bodies, the invention can
be put into operation inexpensively. No individual installed parts
are necessary.
[0021] The floating bodies can be secured by measures such as an
interconnection or covering against undesirable suction by
pumps.
[0022] Using the invention, the advantage of attaining a reduced
evaporation in the hotwell is therefore achieved. This means that a
smaller quantity of moisture is created, as a result of which the
air quantity which is required for the drying is reduced in turn.
This benefits the drying especially in the region of the
low-pressure turbine section and in the region of the final stages.
As a result, the cost of drying is lower and regions with increased
moisture because of evaporation of the condensate are minimized.
Furthermore, the risk of corrosion and the subsequent damage to the
turbine which is associated therewith is reduced.
[0023] Furthermore, by using a large number of floating bodies no
individual adaptation to the shape of the condenser is required.
The floating bodies are automatically adapted to the current
condenser geometry. Consequently, retrofitting of existing plants
is possible in a simple manner.
[0024] The characteristics, features and advantages of this
invention which are described above, and also the way in which
these are achieved, become more clearly and more plainly
comprehensible in conjunction with the following description of the
exemplary embodiments which are explained in more detail in
conjunction with the drawings.
[0025] Exemplary embodiments of the invention are described below
with reference to the drawings. This drawing is not intended to
definitively represent the exemplary embodiments, but rather the
drawing, where useful for explanation, is embodied in schematized
and/or slightly distorted form. With regard to supplements to the
teachings which are directly recognizable in the drawing, reference
is made to the applicable prior art.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] In the drawing:
[0027] FIG. 1 shows a cross-sectional view of a condenser,
[0028] FIG. 2 shows a cross-sectional view of a first embodiment
according to the invention of the floating bodies,
[0029] FIG. 3 shows a further embodiment of the floating bodies
according to the invention.
DETAILED DESCRIPTION OF INVENTION
[0030] FIG. 1 shows a cross-sectional view of a condenser 1 for a
steam power plant, which is not shown in more detail. The condenser
1 comprises a plurality of tube bundles 2 which are arranged in a
steam flow 3. Cooled water flows through the tube bundles 2, which
leads to the water vapor from the steam flow 3 condensing on the
surfaces of the tube bundles 2 and, as water, coming into a region
4 in which the water collects to form a condensate 5. The steam
flow 3 is fluidically connected to a low-pressure turbine section.
Furthermore, the condenser 1 comprises air coolers 6 which are
arranged in the region of the tube bundles 2.
[0031] The condensate 5 forms a condensate surface 7.
[0032] According to the invention, floating bodies 8 are arranged
on this condensate surface 7. In FIG. 1, for reasons of clarity,
only three floating bodies 8 are provided with the designation 8.
These floating bodies 8 wet the condensate surface 7 and
consequently reduce the contact area of the condensate surface 7
with the environment. The floating bodies 8 are of spherical and/or
sphere-like design. Optionally, other shapes are also possible, as
is the simultaneous use of different shapes and sizes.
[0033] Shown in FIG. 2 by way of example is an arrangement in which
the floating bodies 8 are arranged one above the other in a
plurality of rows, wherein the floating bodies 8 have different
sizes and are of spherical design in a first approximation.
[0034] FIG. 3 shows a further embodiment of the invention. The
floating bodies 8 are of sphere-like design in FIG. 3 and are also
arranged one above the other in layers. Similarly, the floating
bodies 8 are designed with different sizes.
[0035] A further embodiment of the floating bodies 8 lies in the
fact that these are of unsymmetrical design, which prevents
rotation. As a result, the surface can dry more quickly.
[0036] The specific gravity of the floating bodies 8 is different
and can be selected so that the steam flow cannot lift these out of
the condensate. The floating bodies 8 can also have different
weights so that, for example, a better covering of the condensate
surface 7 is achieved. By the same token, a different density is
suitable for this purpose.
[0037] The number of floating bodies 8 is selected to be of
sufficient size in order to cover the surface of the condensate in
the hotwell 9. The number of floating bodies 8, however, can also
be significantly greater in order to therefore form a second layer
of floating bodies 8, for example.
[0038] The floating bodies 8 are preferably equipped with
non-absorbent surfaces so that in the ideal case no wetting of the
surfaces takes place.
[0039] Although the invention has been fully illustrated and
described in detail by means of the preferred exemplary embodiment,
the invention is not then limited by the disclosed examples and
other variations can be derived by the person skilled in the art
without departing from the scope of protection of the patent.
* * * * *