Flue gas desulphurization with a water recovery
facilitv
5 The invention is directed at a flue gas treatment
plant, comprising a flue gas desulphurization plant
with an assigned flue gas cooler which is preferably
designed as a spray scrubber, is connected downstream.
with regard to the routing of a flue gas of the flue
10 gas desulphurization plant and which can be set Ln a
line connection carr,ying desulphurized flue gas to the
flue gas desulphurization plant and which has a
connected cooling water circuit, a heat exchanger or a
cooling tower being arranged in the cooling water
15 circuit, and the cooling water circuit has a line
connection to the flue gas desulphurization plant.
The invention is directed, furthermcre, to a flue gas
treatment method in which the flue gas is desulphurized
20 in a flue gas de~ul~hurizatiopnl ant, with the addition
of process water, and is cooled subsequently by means
of cooling water in a flue gas cooler as a function of
an operating mode selected from in each case
alternatively settable operating modes, the cocling
25 water being cooled in a cooling water circuit with a
heat exchanger or cooling tower arranged therein and
being supplied to the flue gas cooler and/or to the
flue gas desulphurization plant. .
30 Flue gas desulphurization plants (FDP) are used, inter
alia, in conventional fossil-fired power stations. In
these flue gas desulphurization plants,. the flue gas is
subjected to treatment with a sulphur-binding
absorbent. This absorbent may be a limestone-containing
35 suspension, th'e limestone consisting predominantly of
.calcium carbonate (CaC03). This lime scrub, as it is
known, has proved the most successful internationally
as a non-regenerative method. In this method, process
water, in addition to the limestone suspension,. is
supplied to the flue gas desulphurization plant, in the
countercurrent scrubber of the flue gas
desulphurization plant, in countercurrent to the flue
gas rising therein. ~ e ~ e n d ion ~t he size of the steam
5 generator assigned to the flue gas desulphurizttion
plant, on the fuel used and on the load range..
different, but always considerable quantities 05
process water are required when the flue gas
desulphurization plant is in oper~tion. The process
10 water required is supplied by external lines, well
water also often serving as a process water source. In
water-rich areas, supplying a flue gas desulphurization
plant with process water does not present a najor
problem. If, however, a power station and a flue gas
15 desulphurization plant assigned to this are installed
in an area which is low in water and without major
regional water reserves, in order to fulfil the prz~cess
water demand it has to be provided, where appropriate,
over long distances, by means of a pipeline, for
20 example. However, the installation and maintenance of a
pipeline entail high investment, operating and
maintenance' costs, depending on size and length.
Furthermore, in.politically hazardous areas, there is
the fear of the theft of water by tapping the pipeline
25 or of sabotage to the installed pipeline. This. may
restrict or even stop the operation of the ?ewer
station.
It is known from the prior art, for example DE 10 2007
30 043 331 Al, to follow a flue gas desulphurization plant
with a flue gas scrubber in which the flue gas is
cooled by means of a cool washing medium supplied. The
washing medium is extracted from the flue gas scrubber,
routed via a heat exchanger and recirculated intzI the
35 flue gas scrubber. Part of the washing medium may a l ~ o
be supplied to the preceding flue gas desulphurization
plant.
- 3 -
r
The object on which the invention is based is to
provide a solution which allows flue gas
desulphurization which saves cooling and process 'water
and recovers cooling and process water.
In a flue gas treatment plant of the type designated in
more detail in the introduction, this object is
achieved in that, downstresm of the, heat exchanger or
the cooling tower (16), the cooling water circuit
10 comprises a water reservoir which is fed from the
cooling water circuit and can be set in a line
connection which feeds in process ard/or cooling wate~
with the cool'ing water circuit (15) and the flue gas
desulphurization plant (2).
In a flue gas treatment method of the type designated
in more detail in the introduction, this objecz is
achieved, according to the invention in that, as a '
function of the operating mode selected in each case,
20 cooled circuit water is supplied to a water reservoir
which is arranged in the cooling .water circuit of the
cooling water downstream of the .heat exchanger or
cooling tower, is fed from the cooling circuit and can
be set in a line connection which feeds in process
25 and/or ,cooling water , with the cooling water circuit
(15) and the flue gas de~ul~hurizatiopnl ant (2) and/or
circuit cooling water is extracted from the water
reservoir and is supplied as cooling or process water
to the flue gas desulphurization plant and/or the flue
30 gas cooler.
Further expedient refinements and advantageous
developments of the invention- are the subject-matter of
the respective subclaims.
35
By virtue of the fundamental idea on which the
invention is based, flue gas desulphurization :dhich
saves cooling and process water and which recovers
ORIGINAL
- 4 -
I
cooling and process water is possible. With appropriate
dimensioning of the water reservoir, independent flue
gas desulphurization is possible at any operating time
point of flue gas desulphurization, that is to say at
any time of the year, by means of a respective
operating. mode. This is achieved by effective
utilization and configuration of the cooling capac.ity .
In periods of time with cooler ambient temperat~res,
during the cooling of the flue gas in the flue gas
cooler by condensing out from the flue gas, a circuit
cooling - water excess is generated which is
(intermediately) stored in the water reservoir. In
times of higher, that is to say warmer ambien:
temperatures, the cooling water circuit is then fed and
supplemented with additional water from the water
reservoir, and consequently a sufficiently high cooling
water mass flow is supplied both to the flue gas
desulph~rization.planta nd to the flue gas cooler.
In this case, switching in the respective operating
mode takes place, depending on the time of year and/or
time of day, as a function of the ambient temperature
available for cooling.
Expediently, therefore, the flue gas treatment ?lant
according to the invention is equi?ped with a closed
air-cooled system for cooling the cooling water circuit
water or process water. In refinement, therefore, the
invention provides for the cooling tower or the heat
exchanger to constitute dry cooling for the cc~ling
water circuit water. There is likewise provis.io~,
according to a refinement of the invention, foz tke
cooling tower or the heat exchanger to have air coolir-g
with indirect heat transmission to the cooling circuit
35 water.
In order to achieve sufficient condensation of water
out of the flue gas in the flue gas cooler, acccrding
ORIGINAL
to a development of the invention it is advantageous
that the flue gas cooler has a cooling capacity which
cools the flue gas to a temperature below the flue gas
desulphurization plant outlet temperature.
5
So that different operating modes in terms of the
routing of a flue gas and/or the routing of circuit
water or process water can be ~mplemented, depending on
the time of year and/or time of day and on the external
10 ambient temperature established in each case, the flue
gas treatment plant is distinguished, furthermore, in
that the line connection has formed in it a firs:
regulatable cooling water distribution of the circui:
cooling water which distributes the circuit water into
15 a water reservoir supply line leading into the water
reservoir and/or into a cooling water or process water
supply line leading to the flue gas desulphurization
plant and/or into a connecting line line-connected to
the flue gas cooler. By regulatable distribution of the
20 circuit cooling water being formed ~ n dar ranged in the
cooling water circuit, the circuit cooling water can bs
supplied in a directed manner to one or more of th2
elements constituting the water reservoir, flue gas
-desulphurization plant and flue gas cooler, depending
25 on control or regulation.
In this case, it is advantageous to form a further
regulatable distribution of the cooling water by means
of which regulation of cooling or process water
30 extracted from the water reservoir can also be
implemented. In a further refinemerit of the flue gas
treatment plant, therefore, the invention provides fo,r
the line connection to have formed in it a second
regulatable cooling water dist'ribution which
35 distributes cooling water from a water reservoir
extraction line line-connected to the water reservoir
into the cooling water or process water supply line
leading to the flue gas desulphurization plant and/or
into the connecting line line-connected to the flue gas
cooler.
In order, as a function of the operating mode to be set
in each case, also' to provide the possibility of
causing the flue gas leaving the flue gas
desulphurization plant to flow past the flue gas
cooler, according to a further refinement of the
invention it is expedient and advantageous that the
line connection carrying desulphurized flue gas has
formed in it a regulatable flue gas distribution of the
flue gas which distributes the flue gas into a flue gas
supply line leading to the flue gas cooler and/or into
a flue gas discharge line not leading to the flue gas
cooler.
Since, with appropriate dimensioning of the .dater
reservoir, it is possible by means of the flue gas
treatment plant according to the invention to opsrate
this independently of any external cooling or process
water supply, the invention provides, furthermore, for
the flue gas treatment plant to have no external or
additional process water and/or cooling water supply.
This is possible when the maximum holding capacity of
the water reservoir is designed such that it contains
and can dispense the cooling or prpcess water quantity
to be added to the cooling circuit water in times of
higher ambient temperature. The maximum st3rage
capacity is therefore designed for the maximum water
reserve required for the respective season of the year.
As stated above, the fundamental idea on which the f l ~ e
gas treatment method is based is to arrange a water
reservoir in' the cooling. water circuit of the cooling
or process water downstream of the heat exchanger or
cooling tower and, as a function of the operatinq mode
selected in each case, which depends in each case on
the external ambient temperatures, to supply cooled
ORIGINAL
circuit cooling water to the water reservoir and/tz~ to
extract circuit' cooling water from the water reservoir
circuit and supply it as cooling or process water to
the flue gas desulphurization plant and/or to the flue
5 gas cooler. As a result, when there is a sufficiently
cool ambient temperature, more water is extracted by
condensation from the flue gas, since it is cooled to a
temperature lying below the flue gas desulphurizction
plant outlet temperature, than would be necessary for
10 the actual flue gas desulphurization method. This water
which is additionally extracted and recovered, in
comparison with conventional plants, .is intermediately
stored in the water reservoir and is supplied as
cooling or process water to the cocling water ciscuis
15 or the desulphurization plant again in times of higher
external ambient temperature.
Within the framework of the various operating states
and method states selectable from a plurality of
20 operating modes, the invention provides for a first
operating mode to be one in which the desulphurized '
flue gas is supplied to the flue gas cooler and heated
cooling circuit water is supplied from the flue gas
cooler to the cooling tower or heat exchanger ar-d is
25 supplied as cooled cooling or process water to.the flue
gas ,desulphurization plant and/or to the flue gas
cooler and the water reservoir.
In a refinement of the invention, a second, alternative
30 operating mode of the flue gas treatment method is
distinguished in that the desulphurized flue gas is
supplied to the flue gas cooler 2nd heated coz~ling
circuit water is supplied from the flue gas cooler to
the cooling tower or heat exchanger and is supplied as
35 cooled cooling or process water, preferably
exclusively, to the flue gas desulphurization plart
and/or to the flue gas cooler.
ORIGINAL
Furthermore, ,in a third alternative operating node,
according to the invention the desulphurized flue gas
is supplied to the flue gas cooler and heated coolin-3
,circuit water is supplied from the flue gas cooler t3
5 the cooling tower or heat exchanger and is supplied as
cooled cooling or process wat'er to the flue gas
desulphurization plant and/or to the flue gas c~oler
and also circuit cooling water is extracted frorc the
water reservoir and is supplied to the flue gas
10 desulphurization plant and/or to the flue gas cooler.
Finally, a fourth operating mode is distinguished in
that the desulphurized flue gas is supplied to a flue
gas discharge line not leading to the flue gas cooler
15 and circuit cooling water is extracted from the water
reservoir and is supplied as (cooled) cooling or
process water to the flue gas desulphurization plant.
I The invention is explained in more detail below, by way
20' of example, with reference to the drawing, in which:
Fig. 1 shows a diagrammatic illustration of the
overall circuitry of a flue gas
desulphurization plant according to the
25 invention, and
Fig. 2 - 5 show a diaqrammatic illustration of the
plant circuitry in different operating
modes.
30
Fig. 1 shows a flue gas treatment plant, designated as
a whole by 1, which comprises a flue g ~ s
desulphurization plant 2 designed in the form of a
countercurrent scrubber and a flue gas cooler 3
35 designed in the form of a spray sczubber. On the flce
gas outlet side, the flue gas desulphurization plant 2
has a flue gas line 5 leading to a regulatable f l ~ eg ~ s
distribution 4 for the flue gas. A flue gas supply line
ORIGINAL
6 leads from the regulatable flue gas distribution 4 to
the flue gas cooler 3 and issues into the latter. A
flue gas discharge line 7 merges into an exhaust gas
line 8 leading to the chimney. On the flue gas octlet
5 side, the flue gas cooler 3 has a flue gas line 9 which
issues into a distribution 10, by means of which it is
in a line connection to the flue gas discharge line 7
and to the exhaust gas line 8 leading to the chimney.
Via a flue gas supply line 11 issuing into the flue gas
10 desulphurization plant 2, the flue gas coming from the
combustion chamber or steam generator of a fossil-fired
power station, after it has flowed through an
electrostatic filter, is introduced into the flue gas
desulphurization plant 2. In the exemplary embodinent,
15 a limestone-containing liquid, as an absorbent in tht
form of a suspension 12, is supplied as
desulphurization medium to the flue gas
desulphurization plant. The gypsum suspension 13, and
waste water 14 which are formed during desulphurization
20 by the limestone suspension are discharged from the
flue gas desulphurization plant. The flue gas cooler 3
has an assigned cooling water circuit designated as a
whole by 15. A cooling tower 16 with dry cooling for
the cooling water circuit water is arranged ir~ the
25 cooling water circuit 15. Cooling water or process
I
water coming from the flue gas cooler 3 and h3ated
after contact with the flue gas flowing through the
flue gas cooler 3 is supplied to the cooling towsr 16
via a cooling tower supply line 17 and is cooled there
30 within a line section 18 indirectly by cooling air
flowing in countercurrent from the bottom upwards in
the cooling tower. The cooling water or process water
flows from the cooling tower 16 via a cooling tower
discharge line 19 to a first regulatable cooling water
35 distribution 20. Connected to this first regulatable
cooling water dis,tribution is a , cooling water or
process water recirculation line 21, by means of which
the cooling water or process water can be recirculated,
ORIGINAL
cooled, into the flue gas cooler 3. Furthermore,
connected to the first regulatable cooling water
distribution 20 is a water reservoir supply line 22, by
means of which cooled cooling water or process water
5 can be introduced into a water reservoir 23. Moreover,
the water reservoir 23 has a water reservoir extraction
line 24 which issues into a second regulatable cooling
water distribution 25. Via a connecting line 26, the
first regulatable cooling water distribution 20 and the
10 second regulatable cooling water distribution 25 are in
fluid-conducting connection with one another and with
the cooling water or process water recirculation
line 21. The second regulatable .cooling water
distribution 25 is connected via z cooling water or
15 process water supply line 27 :o the flue gas
desulphurization plant 2. Moreover, necessary and
conventional pumps 28, not explained in any more
detail, are arranged in the various lines.
20 The cooling capacity of the dry cooling of the cooling
tower 16 is designed in such a way that, by means of
the cooling water supplied to the flue gas cooler 3 via
the cooling water or process water recirculation
line 21, a temperature of the flue gas flowing in via
25 the respective flue gas supply line 6 is reached and
set in the flue gas cooler 3 which lies below the flue
gas desulphurization plant outlet temperature at which
the flue gas flows into the flue gas line 5.
30 Figures 2 to 5, then, illustrate diagrammatically
various alternative operating modes and runnings of .the
flue gas treatment plant 1, the lines or pl'ant par-s 0.r
plant' elements not used in the respective operating
mode being illustrated by dashes.
Fig. 2 shows a first. operating mode or operating state
designated as "waste water oversupply". This is run
when there are suf.ficiently cool ambient temperatures
and,'where appropriate, there is a low or too low a
water level in the water reservoir 23. In this first
operating mode, the flue gas desulphurized in the flue
gas desulphurization plant 2 is conducted via the flue
5 gas line 5, the regulatable flue gas distribution 4 and
the flue gas supply line 6 into the flue gas cooler 3
before it then passes through the flue gas line 9 and
the distribution 10 into the exhaust gas line 8. In
this first operating mode, the cooling water or process
10 water' heated in the flue gas cooler 3 is pumped viz the
cooling tower supply line 17 into the cooling tower 1,5
or air cooling tower. It comes there into indirecz
contact with the ambient air in the line section 18.
The then (re)cooled cooling water or process water is
15 supplied by means of the cooling tower discharge
line 19 to the first regulatable cooling water
distribution 20. In this first oper~ting mode, this is
set in such a way that both cooling water is cond.~cted
into the connecting line 26 and from there through ths
20 second regulatable cooling water distribution 25 and
the cooling water or process water supply line 27 int3
the flue gas desulphurization plant 2 and cooling uater
is supplied through the cooling water or process iqater
recirculation line 21 to the flue gas cooler 3.
25 Moreover, cooling water or process water is introduced
into the water reservoir supply line 22 and is supplied
to the water reservoir 23 by means of this line. With
sufficient cool ambient temperatures, this operating
mode is maintained until the water reservoir is filled
30 up to its intended maximum filling level 29. The
maximum filling level 29 can be adapted to the water
reserves required for the respective season of the
year.
35 In the second operating mode illustrated in Fig. 3,
there are sufficiently cool ambient temperatures and
there is a sufficiently full water reservoir 23, and
therefore the latter must not or cannot be filled any
ORIGINAL
further. In this second operating mode, the flue gas
desulphurization plant 2 and flue gas cooler 3 operate
in equilibrium. Once again, as in the first operating
mode, the flue gas is supplied from the flue gas
5 desulphurization plant 2 to the flue gas cooler 3 and
is introduced from this into the exhaust gas line 8.
The warmed or heated cooling water or process water is
again supplied from the flue gas cooler 3 tc the
cooling tower or air cooling tower 16, but then, in the
10, first regulatable cooling water distribution 20, is
supplied only to the line 26, the cooling water or
process water recirculation line 21 branching off from
this, and via the second regulatable cooling xater
distribution 25 of the line 27. In this case, an
15 equilibzium is established in as much as the recooled
cooling water or process water is distributed unif3rmly
or in a respectively desired ratio to the cooling water
.or process water recirculation line 21 and to the
cooling water or process water supply line 27, so that
20 the mass flow of cooling water or process ~ater
introduced into the flue gas desulphurization plant 2
is equal to the mass flow of warmed cooling water xhich
is drawn off from the flue gas cooler 3 via the cc~ling
tower supply line 17.
25
In a third operating mode illustrared in Fig. 4, the
operating state of a "waste water under supply" is
illustrated. This third operating'mode is established
or is set when the ambient temperatures are too hich
30 for sufficient or desired cooling of the cooling xater.
In this operating mode, as in the previously described
operating modes, the flue gas is conduct'ed from the
flue gas desulphurization plant 2 into the flue g ~ s
cooler 3 and from this into the exhaust g.as line 8. The
35 recooled cooling water is once again supplied via the
cooling water or process water recirculation line.21 to
the flue gas cooler 3 and, via the lines 26 and 27, to
the flue gas desuhphurization plant 2. ow ever, the
cooling water or process water flowing into the cooling
tower discharge line 19 from the cooling tower 16 or
air cooling tower has a higher ternper'ature than, in
particular, the first and the second operating mode.
5 Only a small mass of water would have to be condensed
out of the flue gas by means of the cooling water or
process water having this higher temperature.
Particularly for operating the flue gas
desulphurization plant 2, however, this would nct be
10 sufficient. In order, nevertheless, to ensure
continuous desulphurization in the flue gas
' desulphurization plant 2, there is provision, in this
third operating mode, that a part of the cooling water
or process water previously recovered during earlier
15 operating phases in other operating modes and stored in
the water reservoir 23 is supplied via the water
reservoir discharge line 24 to the second regulatable
cooling water distribution 25 and is fed into the
cooling water or process water supply line 27 or, if
20 desired, additionally also into the connecting line 26
and is thereby supplied to the plant units connected in
each case. In this third operating mode, the additional
cooling water or process water fed into the system from
the water reservoir 23 compensates for the lower
25 extracted mass flow of water from the flue gas.
If a fourth operating mode illustrated in Fig. 5 is
u'sed, there are such high temperatures that cooling cf
the process water or cooling water is not possible. In
30 this fourth operating mode, the flue gass leaving the
' flue gas desulphurization plant 2 then 'flows past the
flue gas cooler 3 by being introduced in the _
regulatable distribution 4 directly into the flue gas
discharge line 7 and being guided from there' throuqh
35 the distribution 10 to the exhaust gas line 8.. The
process water required in the flue gas desulphurization
plant 2 is provided from the water reservoir 23 and is
introduced via t.he water reservoir discharge line 24,
ORIGINAL
the second regulatable cooling water distribution 25
and the cooling water or process water supply1 lins 27
into the flue gas desulphurization plant 2. In this
mode, therefore, the process water required in the flue
5 gas 'desulphu.rization plant also comes 100% and
exclusively from the water reservoir 23.
Furthermore, overall, the flue gas treatment plant 21
is not connected to a further fluid line which supplies
10' cooling water or process water from outside. The system
therefore operates independently in terms of cooling
water and process water in all four operating modes.
Overall, therefore, the invention provides a flue gas
15 treatment plant 1, the flue gas desulphurization
plant 2 of which and the assigned flue gas cooler 3 of
which together both operate and can be operatei
independently in terms of the supply of cooling -dater
and/or process wafer. There is no need for the external
20 supply of cooling water or process water, for example
by means of. a pipeline, and therefore the problems
mentioned in the introduction and the costs caused
thereby are avoided. The required cooling water or
process water is provided and (re-)cooled in a .self-
25 sufficient manner by the plant.

ORIGINAL
Patent Claims
1. Flue gas treatment plant (I), comprising a flue
gas desulphurization plant (2) with an assigned flue
5 gas cooler (3) which is preferably designed as a spray
scrubber, is connected downstream with regard to the
routing of a flue gas of the flue gas desulphurization
plant (2) and which can be set (4) in a line conneztion
(5, 6) carrying desulphurized flue Gas to the flue gas
10 desulphurization plant (2) and .which has a connected
cooling water circuit (15), a. heat exchanger or 'a
cooling tower (16) being arranged in the cooling water
circuit (15), and the cooling water circuit (15) has a
line connection (26, 27) to the flue gas
15 desulphurization ' plant (2), charasterized' in :hat,
downstream of the heat exchanger or the cooling xower
(16), the cooling water circuit (15) comprises a water
reservoir (23)' which is fed from, the cooling water
circuit (15) and can be set in a line connection wh'ich
20 feeds in process and/or cooling water with the cooling
water circuit (15)' and the flue gas desulphurization
plant (2) .
2. Flue gas treatment plant (1) according to Claim 1,
'25 characterized in that the heat exchanger,or the cooling
tower (16) constitutes dry cooling for the co3ling
water circuit water.
3. Flue gas treatment plant (1) according to Cl2im 1
30 or 2, characterized in that the heat exchanger or the
cooling tower (16) has air cooling with indirect heat
transmission to the cooling circuit water.
4. Flue gas treatment plant (1) according to one of
35 the preceding claims, characterized in that the flue
gas cooler (3) has a cooling capacity which cools the
flue gas to a temperature below the flue gas
desulphurization plant outlet temperature.
ORIGINAL
5. Flue gas treatment plant (1) according to one of
the preceding claims, characterized in that the line
connection (26, 27) has formed in it a first
5 regulatable cooling water distribuzion (20) of the
circuit cooling water which distributes the circuit
cooling water into a water reservoir supply line (22)
leading into the water reservoir (23) and/or into a
cooling water or process water supply line (27) leading
10 to the flue gas desulphurization plant (2) and/or into
a connecting line (26) line-connected to the flue gas
cooler (3).
6. Flue gas treatment plant (1) according to one of
15 the preceding claims, characterized in that the line
connection , (26, 27) has formed in it a second
regulatable cooling water distrikution (25) which
distributes cooling water from a water .reservoir
extraction ' line (24) line-connected to the water
20 . reservoir (23) into the cooling water or process water
supply line (27) leading to .the flue gas
desulphurizat-ion plant (2) and./or into the connect in^
line (26) line-connected to the flue gas cooler (3).
25 7. Flue gas treatment plant (1) according to oEe of
the preceding claims, characterized in that. the lins
connection (5, 6) carrying desulphurized flue gas has
formed in it. a regulatable flue gas distribution (4)
which distributes the flue gas into a flue gas supply
30 line .(6) leading to the flue gas cooler (3) and/or into
a flue gas discharge line (7) not leading to the flue
gas cooler (3).
8. Flue gas treatment plant (1) according t,o one of
35 the preceding claims, characterized in that it has no
external or additional process water and/or coaling
water supply.
ORIGINAL
9. Flue gas treatment method, in which the flue gas
is desulphurized in a flue gas desulphuriz~tior!
plant (2), with the addition. of process water, and is
subsequently cooled in a flue gas cooler (3) by means
of cooling water as a function of an operating mode
selected fr;m in each case alternatively settable
operating modes, the cooling water being cooled in a
cooling water circuit (15) with a heat exchanger or
cooling tower (16) arranged therein and being supplied
to the flue gas cooler (3) and/or to the flue gas
desulphurization plant (2), characterized in that, as a
function of the operating mode selected in each case,
cooled circuit cooling water is supplied to a vatez
reservoir (23) which is arranged in the cooling watez
circuit (15) of the cooling water downstream of the
heat exchanger or cooling tower (16), is fed frorr the
cooling water circuit (15) and can be set in a line
connection which feeds in process and/or cooling water
with the cooling water circuit (15) and the flue gas
desulphurization plant (2) and/or circuit cooling water
is extr.acted from the water reservoir (23) and is
supplied as cooling or process water to the flue gas
desulphurization plant (2) and/or to the flue gas
cooler (3).
10. Flue gas treatment method acc3rding to Claim 9,
characterized in that, in a first operating mode of the
alternative operating modes, the desulphurized flue gas
is supplied to the flue gas cooler (3) and heated
cooling circuit water is supplied from the flu€ gas
cooler (3) to the cooling tower (16) or heat exchmger
and is supplied as cooled cooling or process watsr to
the flue gas desulphurization plant (2) and/or to,the
flue gas cooler (3) and the water reservoir (23).
11. Flue gas treatment method according to Claim 5,
characterized in that, in a second operating mode of
the alternative operating modes, the desulphurized flue
ORIGINAL
-gas is supplied to the flue gas cooler (3) and heated
cooling circuit water is supplied from the flue gas
a cooler (3) to the cooling tower (16) or heat exchcnger
.and is supplied as cooled cooling or process w~ter,
5 preferably exclusively, to the flue gas
desulphurization plant (2) and/or to the flue gas
cooler (3).
, 12. Flue gas treatment method according to Claim 9..
10 characterized in that, in a third operating mode of the
alternative operating modes, the desulphurized flue gas
is supplied to the flue gas cooler (3). and heated
cooling circuit water is supplied from the flue gas
cooler (3) to the cooling tower (16) br heat exchanger
15 and is supplied as cooled cobling or process water to
the flue gas desulphurization plant (2) and/or tc the
flue gas cooler (3) and also circuit cooling water is
extracted from the water reservoir (23) and is sup?lied
to the flue gas desulphurization plant (2) and/or t.3
20 the flue gas cooler (3) .
13. Flue gas treatment method according to Claim 9,
characterized in that, in a fourth operating mode of
the alternative operating modes, the desulphurized flue
25 gas is supplied .to a flue gas discharge line ( 7 : 30t
leading to the flue gas cooler and circuit cooling
water is extracted from the water reservoir .(23) and is
supplied as cooling or process water to the flue gas
desulphurization plant (2).
Dated this the 8th day of June 2012.