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How Coal Thermal Power Stations Work (Part 3)

WEBVTT
Kind: captions
Language: en

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- [Jon] Hi, Jon here, in this video
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we're gonna be looking at
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a coal-fired power
station's water systems.
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Specifically, we're gonna be looking at
00:00:09.497 --> 00:00:13.210
the condensate system, the makeup system
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and the boiler feedwater system.
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This video continues on from
some of the other videos
00:00:18.900 --> 00:00:21.890
we created in the coal-fired
power plant series,
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so be sure to check those out
00:00:23.100 --> 00:00:24.650
if you haven't done so already.
00:00:26.080 --> 00:00:27.720
So here is our drawing,
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showing each of the main systems
00:00:29.400 --> 00:00:31.760
of a coal-fired power station.
00:00:31.760 --> 00:00:33.400
The systems that we're interested in
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are the condensate system,
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the makeup water system and
the boiler feedwater system.
00:00:38.650 --> 00:00:42.210
These systems are shown
on the diagram in blue
00:00:42.210 --> 00:00:45.760
although the raw water
system is also shown in blue.
00:00:45.760 --> 00:00:48.620
The condensate system on our diagram
00:00:48.620 --> 00:00:53.620
consists of a condenser, a
condensate pump, a heater
00:00:54.890 --> 00:00:57.881
and at the point the condensate
enters, the deaerator,
00:00:57.881 --> 00:01:01.150
the condensate becomes feedwater.
00:01:01.150 --> 00:01:02.520
The makeup water system,
00:01:02.520 --> 00:01:06.990
usually taken from a lake
or river or city water grid,
00:01:06.990 --> 00:01:10.133
is shown here and it
flows to the deaerator.
00:01:11.630 --> 00:01:14.560
The boiler feedwater
system begins directly
00:01:14.560 --> 00:01:16.000
after the deaerator
00:01:16.000 --> 00:01:18.663
and it continues all
the way to our boiler.
00:01:19.790 --> 00:01:21.520
In our coal-fired power station,
00:01:21.520 --> 00:01:24.703
this particular boiler
is a water tube boiler.
00:01:25.800 --> 00:01:29.250
Let's start by having a look
at the makeup water system.
00:01:29.250 --> 00:01:33.860
Makeup water is sourced
externally from the power plant.
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It is water that you
add to the condensate,
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or boiler feedwater system,
00:01:38.860 --> 00:01:42.000
in order to make up for any water losses
00:01:42.000 --> 00:01:43.853
that may have occurred in the system.
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We can't just add makeup
water to the system
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because the water needs
to be treated first.
00:01:50.200 --> 00:01:53.740
It contains too much Oxygen, too much CO2,
00:01:53.740 --> 00:01:56.070
we need to correct the pH level
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and we also need to filter the water
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to reduce the number of
total suspended solids
00:02:01.410 --> 00:02:05.540
and pass the water through
a demineralizer plant.
00:02:05.540 --> 00:02:07.170
So there's a lot of
stuff that needs to occur
00:02:07.170 --> 00:02:10.503
before we can add water
to power plant system.
00:02:12.090 --> 00:02:15.670
Makeup water is often added to a deaerator
00:02:15.670 --> 00:02:19.280
where it can be treated both
mechanically and chemically
00:02:19.280 --> 00:02:20.660
although it may also be added to
00:02:20.660 --> 00:02:22.723
the steam turbine condenser.
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Let's now take a look
at the condensate system
00:02:25.820 --> 00:02:28.300
because as condensate
flows through the system
00:02:28.300 --> 00:02:30.607
it is then gonna become boiler feedwater.
00:02:31.780 --> 00:02:35.620
Condensate may be gathered
at any part of the system
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and fed back to the deaerator
or perhaps even the condenser.
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Condensate is water, specifically
it is condensed steam.
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The steam that we created
by a water tube boiler
00:02:49.550 --> 00:02:53.090
has given up a bit of its
heat and it has condensed.
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Throughout the entire system,
00:02:54.720 --> 00:02:58.670
not all of the steam will give
up its heat at the same time.
00:02:58.670 --> 00:03:01.600
And because of this, we'll
need to have steam traps
00:03:01.600 --> 00:03:03.790
and drains throughout the entire system
00:03:03.790 --> 00:03:07.510
so that we can direct that
condensate back to a storage area
00:03:07.510 --> 00:03:09.953
or a deaerator or the condenser.
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The majority of the steam,
00:03:12.950 --> 00:03:17.170
is gonna be condensed in
00:03:17.170 --> 00:03:19.300
The steam turbine condenser is installed
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directly underneath the
low pressure steam turbine.
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By the time the steam
reaches the condenser,
00:03:25.420 --> 00:03:28.930
it has given up the majority of its heat
00:03:28.930 --> 00:03:32.980
and we've used that heat to
rotate the steam turbine.
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Now in order to return the
steam back to the boiler
00:03:35.770 --> 00:03:37.730
in an efficient manner,
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we're gonna cool the
steam in the condenser
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and cause it to condense.
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When it condenses, we have condensate.
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On our example of a power station here,
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if we go round the back
of the power station
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we can actually have a
look at the condenser
00:03:56.290 --> 00:03:59.263
which is installed
underneath the steam turbine.
00:04:00.220 --> 00:04:01.490
We have our high pressure
00:04:01.490 --> 00:04:03.490
and intermediate pressure turbines here,
00:04:04.690 --> 00:04:06.590
and we have our lower pressure turbine
00:04:07.880 --> 00:04:09.333
within this casing here.
00:04:10.430 --> 00:04:13.070
Steam from the low pressure turbine
00:04:13.070 --> 00:04:17.100
is exhausted to the space
underneath the turbine
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which is a condenser.
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After we've condensed the steam,
00:04:20.630 --> 00:04:23.700
it will gather in the
lower part of the condenser
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in an area that we
refer to as the hotwell,
00:04:26.809 --> 00:04:28.459
that is this section around here.
00:04:29.580 --> 00:04:32.840
Once that has occurred, we'll
then pump the condensate
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using a centrifugal pump.
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We can actually see that the
condensate is being drained out
00:04:40.433 --> 00:04:41.740
through this pipe here
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and is going back into our power station.
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These other large connections
that come along here,
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these are actually our
cooling water lines,
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you can see them on this side.
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And if we zoom out,
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we can see that they
connect to a cooling tower
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and the water is coming along here,
00:05:02.320 --> 00:05:05.090
passing through the condenser along here
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and going back to our cooling tower.
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In this way, we can use the cooling water
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from the cooling tower
to cool down the steam
00:05:13.634 --> 00:05:14.963
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So we've left the condenser,
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we've sucked the condensate
out of the hotwell area
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and it's gonna pass
through a centrifugal pump.
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So now we're looking
at a centrifugal pump.
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Specifically, this is a single stage
00:05:34.280 --> 00:05:37.000
overhung centrifugal pump.
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I'll pause the animation for a moment
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and I'll show you exactly how it works.
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The condensate from the hotwell
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is gonna be sucked in
through this area here,
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it's gonna go towards
the eye of the impeller,
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which is the center point,
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and it's gonna fill up this whole section
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and then it's gonna flow
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through the impeller outwards radially.
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If we push the play
button on the animation,
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you'll see that the impeller
is rotating this way,
00:06:05.430 --> 00:06:09.030
we're gonna throw the
condensate radially outwards
00:06:09.030 --> 00:06:10.620
from the shaft
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and it's gonna enter the volute casing.
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The volute casing surrounds the impeller
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and it looks a little bit like a snail.
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The liquid comes around
and as it comes around
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it's gonna be discharged at
the top of the centrifugal pump
00:06:26.093 --> 00:06:27.690
through this section here
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and we're gonna send the
condensate through a heater
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or a series of heaters
00:06:32.940 --> 00:06:34.923
before it reaches a deaerator.
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Depending upon the set up at
your coal-fired power station,
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you may utilize anywhere
between three to nine
00:06:43.140 --> 00:06:47.890
or even more condensate and
boiler feedwater heaters.
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These heaters are simply shell
00:06:49.960 --> 00:06:52.200
and tube type heat exchangers
00:06:52.200 --> 00:06:54.690
and we're gonna use them
to heat up the condensate
00:06:54.690 --> 00:06:56.560
or boiler feedwater
00:06:56.560 --> 00:06:59.140
in order to increase
the process efficiency
00:06:59.140 --> 00:07:02.083
and not shock our water tube boiler.
00:07:03.050 --> 00:07:04.633
If we take a cross section.
00:07:06.270 --> 00:07:10.610
You can see that we have a fluid
coming in on the left side,
00:07:10.610 --> 00:07:12.740
it's flowing along through the tubes,
00:07:12.740 --> 00:07:14.860
comes out here, comes back around,
00:07:14.860 --> 00:07:17.620
and flows back the other way.
00:07:17.620 --> 00:07:20.260
We have another fluid
which comes in through here
00:07:20.260 --> 00:07:23.050
and is directed around some baffles
00:07:23.050 --> 00:07:25.923
and drops down out of this nozzle here.
00:07:27.230 --> 00:07:28.940
So just have a look from another angle
00:07:28.940 --> 00:07:31.000
for those that haven't seen it before.
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We would have, for example,
00:07:33.370 --> 00:07:35.830
condensate entering
through this lower pipe
00:07:36.840 --> 00:07:41.780
flowing into our tubes,
flows along the tubes,
00:07:41.780 --> 00:07:44.730
to the opposite end of the heat exchanger,
00:07:44.730 --> 00:07:49.050
does a U-turn, flows back the other way,
00:07:49.050 --> 00:07:52.340
so we're gonna go all the
way over to the left here
00:07:52.340 --> 00:07:54.810
and then the condensate or feedwater,
00:07:54.810 --> 00:07:58.000
depending on where in the
system this heater is installed,
00:07:58.000 --> 00:08:00.663
will flow out of the heater.
00:08:02.000 --> 00:08:07.000
Meanwhile, the steam will
be flowing in to the heater,
00:08:07.490 --> 00:08:11.060
through these baffles here,
00:08:11.060 --> 00:08:12.230
that surround the tubes
00:08:12.230 --> 00:08:16.013
and drop out of this
nozzle or pipe over here.
00:08:17.250 --> 00:08:18.790
If I take away the exterior,
00:08:18.790 --> 00:08:21.490
we can have a better look at the baffles.
00:08:21.490 --> 00:08:23.580
We'll come around the other side
00:08:23.580 --> 00:08:25.190
and you can see the baffles,
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they surround the tubes
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and you can take the tubes away as well.
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And these baffles are
gonna direct the steam
00:08:33.530 --> 00:08:36.603
as it flows across the tubes.
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The steam itself is gonna be taken from
00:08:41.610 --> 00:08:44.040
high pressure, intermediate pressure
00:08:44.040 --> 00:08:46.763
or low pressure steam turbines.
00:08:48.180 --> 00:08:49.650
You'll often see these heaters
00:08:49.650 --> 00:08:53.590
fitted in a cascade style system
00:08:53.590 --> 00:08:55.400
and as the steam condenses,
00:08:55.400 --> 00:08:59.350
as it gives up its heat to
the condensate or feedwater,
00:08:59.350 --> 00:09:00.430
some of it will collect
00:09:00.430 --> 00:09:03.210
in a lower part of the heat exchanger
00:09:03.210 --> 00:09:06.680
and we're gonna drain that condensate off
00:09:06.680 --> 00:09:09.700
to the next heater which
is at a lower pressure
00:09:09.700 --> 00:09:12.670
and we'll use the steam again to heat up
00:09:12.670 --> 00:09:14.603
the condensate or the feedwater.
00:09:15.710 --> 00:09:18.940
In this way, we can make sure
we're extracting enough heat
00:09:18.940 --> 00:09:20.530
from the steam as possible
00:09:20.530 --> 00:09:22.930
before it enters the condensate system
00:09:22.930 --> 00:09:24.850
and it's treated and heated
00:09:24.850 --> 00:09:26.813
and turned into boiler feedwater again.
00:09:27.920 --> 00:09:30.110
Another item that's
installed on these heaters,
00:09:30.110 --> 00:09:33.280
is a vent and that allows us to vent off
00:09:33.280 --> 00:09:35.950
non-condensable gases.
00:09:35.950 --> 00:09:38.563
Particularly CO2 and Oxygen.
00:09:39.580 --> 00:09:41.430
So we've gone through our first heater,
00:09:41.430 --> 00:09:44.200
directly after the centrifugal
pump, but just remember,
00:09:44.200 --> 00:09:47.200
there may be more than one set of heaters,
00:09:47.200 --> 00:09:50.730
on very large plants you may
see three different stages
00:09:50.730 --> 00:09:53.360
of heaters, lower pressure,
intermediate pressure
00:09:53.360 --> 00:09:55.450
and high pressure.
00:09:55.450 --> 00:09:58.220
The condensate has been heated up by steam
00:09:58.220 --> 00:10:02.613
in our heater and it's then
gonna be passed to a deaerator.
00:10:04.730 --> 00:10:06.693
So here is a deaerator.
00:10:07.770 --> 00:10:10.190
There are several different
designs that you might have,
00:10:10.190 --> 00:10:11.920
notice that the deaerator itself
00:10:11.920 --> 00:10:14.390
is sitting on a raised platform.
00:10:14.390 --> 00:10:15.750
You'll often find deaerator
00:10:15.750 --> 00:10:18.340
quite high up in power stations.
00:10:18.340 --> 00:10:19.300
And the reason for this,
00:10:19.300 --> 00:10:22.890
is it gives the pumps which
draw from the deaerator,
00:10:22.890 --> 00:10:25.350
a positive head of pressure.
00:10:25.350 --> 00:10:27.240
The pumps are often centrifugal
00:10:27.240 --> 00:10:29.950
so they need liquid in
order to be able to pump.
00:10:29.950 --> 00:10:31.750
They will not pump air.
00:10:31.750 --> 00:10:32.583
And for this reason,
00:10:32.583 --> 00:10:35.520
it just makes sense to sit the deaerator
00:10:35.520 --> 00:10:37.943
as high up in the power plant as possible.
00:10:39.070 --> 00:10:43.533
Our condensate is going to
enter through this inlet here.
00:10:44.730 --> 00:10:48.010
It's gonna be sprayed
out of a spray nozzle
00:10:48.010 --> 00:10:50.940
which is represented by this section here.
00:10:50.940 --> 00:10:54.170
And we're gonna spray
it into this spray area
00:10:54.170 --> 00:10:55.650
and it's gonna drop down
00:10:56.730 --> 00:10:59.930
and then it's gonna gather
in the lower part of the tank
00:10:59.930 --> 00:11:01.680
at about this level,
00:11:01.680 --> 00:11:02.513
and at that point,
00:11:02.513 --> 00:11:06.627
our condensate is now
classified as feedwater.
00:11:07.970 --> 00:11:12.250
The tank itself is a boiler feedwater tank
00:11:12.250 --> 00:11:15.310
although people will often
call it a deaerator tank.
00:11:15.310 --> 00:11:18.280
We deaerate to reduce the
number of dissolved gases
00:11:18.280 --> 00:11:21.253
in the boiler feedwater and condensate.
00:11:23.040 --> 00:11:26.810
Can see that steam enters the deaerator
00:11:27.927 --> 00:11:29.293
through this pipe here,
00:11:30.300 --> 00:11:31.650
it comes down the pipe
00:11:31.650 --> 00:11:34.780
and it's then discharged
through a sparge pipe
00:11:34.780 --> 00:11:36.353
or sparger pipe.
00:11:37.880 --> 00:11:40.640
Steam comes out here, you
can see our yellow arrows,
00:11:40.640 --> 00:11:44.020
it will bubble up through
our boiler feedwater,
00:11:44.020 --> 00:11:46.590
it will enter the top of the deaerator
00:11:46.590 --> 00:11:48.930
and some of the steam will also rise up
00:11:48.930 --> 00:11:50.960
through this section here,
00:11:50.960 --> 00:11:53.153
looks a little bit like a demister,
00:11:54.070 --> 00:11:55.270
and as it rises up,
00:11:55.270 --> 00:11:57.960
we've got a very large
contact surface area
00:11:57.960 --> 00:12:00.870
between our condensate
which is being sprayed in
00:12:00.870 --> 00:12:02.440
and our steam
00:12:02.440 --> 00:12:04.600
and as we heat up that condensate
00:12:04.600 --> 00:12:08.520
it's gonna release a lot of
the non-condensable gases,
00:12:08.520 --> 00:12:11.010
and we're gonna vent those
non-condensable gases
00:12:11.010 --> 00:12:12.263
and a little bit of steam,
00:12:12.263 --> 00:12:15.853
through this pipe here which is a vent.
00:12:16.750 --> 00:12:19.110
By removing the non-condensable gases,
00:12:19.110 --> 00:12:24.110
specifically CO2, carbon
dioxide and O2, Oxygen,
00:12:24.400 --> 00:12:28.070
we're gonna reduce the risk of corrosion.
00:12:28.070 --> 00:12:31.070
CO2 makes the water more acidic,
00:12:31.070 --> 00:12:34.933
and Oxygen can lead to Oxygen
pitting and general corrosion.
00:12:36.040 --> 00:12:39.080
We may also add chemicals
such as Hydrazine
00:12:39.080 --> 00:12:40.420
to the deaerator,
00:12:40.420 --> 00:12:43.460
which is gonna further
reduce the amount of Oxygen
00:12:43.460 --> 00:12:46.080
dissolved in the boiler feedwater.
00:12:46.080 --> 00:12:49.680
As I say, this is now
our boiler feedwater tank
00:12:50.550 --> 00:12:53.210
and we're gonna draw out boiler feedwater
00:12:53.210 --> 00:12:57.320
through this pipe in
the bottom of the tank.
00:12:57.320 --> 00:12:58.883
That's represented over here.
00:13:00.910 --> 00:13:03.370
Once we draw out the boiler feedwater,
00:13:03.370 --> 00:13:08.240
we can send it to a booster
pump or series of booster pumps,
00:13:08.240 --> 00:13:10.770
maybe we'll also pass it
through another heater,
00:13:10.770 --> 00:13:12.280
a high pressure heater
00:13:12.280 --> 00:13:16.090
and it will go then to
our boiler feedwater pumps
00:13:16.090 --> 00:13:19.493
which are multi-stage centrifugal pumps.
00:13:21.380 --> 00:13:24.993
So here is our multi-stage
centrifugal pump.
00:13:26.440 --> 00:13:29.180
I'll explain to you
exactly how this works.
00:13:29.180 --> 00:13:32.600
These are quite large items
normally and the reason is,
00:13:32.600 --> 00:13:35.930
they actually have to deal
with quite high pressures.
00:13:35.930 --> 00:13:38.180
The reason we have to
increase the pressure
00:13:38.180 --> 00:13:42.140
after the deaerator is because
the water tube boiler itself
00:13:42.140 --> 00:13:45.290
operates with pressures exceeding 200 bar
00:13:45.290 --> 00:13:48.620
which is about 2,900 Psi.
00:13:48.620 --> 00:13:51.030
So we're working with high pressures
00:13:51.030 --> 00:13:52.560
and when you work with high pressures
00:13:52.560 --> 00:13:55.740
you need to have strong
pressure boundaries
00:13:55.740 --> 00:13:58.070
and that's why our boiler feedwater pump
00:13:58.070 --> 00:14:00.500
is quite heavy, quite bulky,
00:14:00.500 --> 00:14:03.500
it's because it needs to
withstand these high pressures
00:14:03.500 --> 00:14:05.103
that it's gonna create.
00:14:06.010 --> 00:14:07.880
So we fed our boiler feedwater
00:14:08.720 --> 00:14:12.453
in through this nozzle or pipe over here,
00:14:13.850 --> 00:14:16.130
it's gonna flow downwards
00:14:16.130 --> 00:14:18.900
into the center of our impeller.
00:14:18.900 --> 00:14:20.700
You can actually see that over here.
00:14:22.320 --> 00:14:26.930
Once the feedwater flows in
to the center of the impeller,
00:14:26.930 --> 00:14:28.720
we're gonna throw it out radially,
00:14:28.720 --> 00:14:31.320
much like we did with the
single stage centrifugal pump
00:14:31.320 --> 00:14:34.950
and we're gonna throw it into a diffuser.
00:14:34.950 --> 00:14:37.020
A diffuser allows us to convert even more
00:14:37.020 --> 00:14:39.740
of the kinetic energy that we generated
00:14:39.740 --> 00:14:44.070
by throwing the liquid out
radially, into pressure.
00:14:44.070 --> 00:14:45.270
Once we've done that,
00:14:45.270 --> 00:14:47.220
we're gonna repeat that process
00:14:47.220 --> 00:14:50.930
by feeding the discharge
water from the first stage
00:14:50.930 --> 00:14:54.580
into the eye of the second stage impeller.
00:14:54.580 --> 00:14:57.120
We'll then throw the liquid out,
00:14:57.120 --> 00:15:00.610
or in our case the boiler
feedwater out, radially,
00:15:00.610 --> 00:15:01.680
the impeller will convert
00:15:01.680 --> 00:15:03.390
some of that kinetic energy to pressure.
00:15:03.390 --> 00:15:05.890
The diffuser ring which is stationery,
00:15:05.890 --> 00:15:08.100
this stainless steel item here,
00:15:08.100 --> 00:15:09.850
is gonna convert even more
00:15:09.850 --> 00:15:12.790
of that kinetic energy into pressure
00:15:12.790 --> 00:15:14.830
and we'll repeat the process by feeding it
00:15:14.830 --> 00:15:18.280
into the next stage
impeller, that third stage,
00:15:18.280 --> 00:15:22.010
our fourth stage and our fifth stage
00:15:22.010 --> 00:15:25.140
which, in our case, is the final stage.
00:15:25.140 --> 00:15:28.800
We've increased the
pressure at every stage,
00:15:28.800 --> 00:15:29.810
once we get to the end
00:15:29.810 --> 00:15:31.770
we have quite a high pressure,
00:15:31.770 --> 00:15:33.870
remember the boiler might be operating
00:15:33.870 --> 00:15:35.780
with feedwater pressures in excess
00:15:35.780 --> 00:15:38.763
of 200 bar or 2,900 Psi.
00:15:39.660 --> 00:15:42.240
And we discharge that boiler feedwater
00:15:42.240 --> 00:15:44.430
up through this pipe
00:15:44.430 --> 00:15:46.880
and then we can feed the boiler feedwater
00:15:46.880 --> 00:15:49.443
then to our water tube boiler.
00:15:50.290 --> 00:15:53.660
So we've taken our condensate
from the condenser,
00:15:53.660 --> 00:15:56.950
we've drawn it out using
a centrifugal pump,
00:15:56.950 --> 00:15:58.420
we've then pumped it to the heater
00:15:58.420 --> 00:16:00.200
to increase its temperature,
00:16:00.200 --> 00:16:01.940
we've then sent it to a deaerator
00:16:01.940 --> 00:16:04.230
to increase its temperature still further,
00:16:04.230 --> 00:16:07.870
whilst also stripping out
some non-condensable gases,
00:16:07.870 --> 00:16:11.220
and then we've then sent it
to a boiler feedwater pump
00:16:11.220 --> 00:16:13.573
and pumped it to our water tube boiler.
00:16:14.420 --> 00:16:15.580
Remember that typically,
00:16:15.580 --> 00:16:18.280
you'll have more than one stage of heaters
00:16:18.280 --> 00:16:22.200
because you want to continuously
increase the temperature
00:16:22.200 --> 00:16:24.300
of the condensate and the boiler feedwater
00:16:25.210 --> 00:16:29.140
before it gets to your water tube boiler.
00:16:29.140 --> 00:16:31.080
The reason you can continually increase
00:16:31.080 --> 00:16:33.220
the temperature of the boiler feedwater
00:16:33.220 --> 00:16:36.210
is because you're increasing the pressure,
00:16:36.210 --> 00:16:38.660
remember that if you
increase the pressure,
00:16:38.660 --> 00:16:42.200
then you increase the
boiling point of a liquid.
00:16:42.200 --> 00:16:43.550
If you decrease the pressure,
00:16:43.550 --> 00:16:46.533
then you decrease the
boiling point of the liquid.
00:16:47.430 --> 00:16:48.560
So knowing this,
00:16:48.560 --> 00:16:50.740
then we know we're gonna
be able to maintain
00:16:50.740 --> 00:16:53.590
a liquid state or a liquid phase,
00:16:53.590 --> 00:16:57.630
and we're not gonna get that
liquid flashing off to steam
00:16:57.630 --> 00:17:01.100
until we add a considerable
amount of heat.
00:17:01.100 --> 00:17:01.960
And that's quite lucky
00:17:01.960 --> 00:17:03.430
'cause that's exactly what we're gonna do
00:17:03.430 --> 00:17:05.673
when we get to our water tube boiler.
00:17:07.530 --> 00:17:10.810
Here is our water tube boiler.
00:17:10.810 --> 00:17:12.883
Let's take a cross section of the boiler.
00:17:14.300 --> 00:17:17.187
If we spin it around, you
can see the internals.
00:17:18.540 --> 00:17:21.070
The boiler feedwater is first gonna be fed
00:17:21.070 --> 00:17:24.433
into this section of the boiler.
00:17:25.890 --> 00:17:28.840
The reason we feed into this section first
00:17:28.840 --> 00:17:31.150
is because this is the coolest area
00:17:31.150 --> 00:17:32.663
of the boiler that we have.
00:17:33.560 --> 00:17:35.227
Combustion takes place in this area
00:17:35.227 --> 00:17:37.833
of the boiler here, the furnace.
00:17:38.900 --> 00:17:40.940
The exhaust gases from combustion
00:17:40.940 --> 00:17:42.410
which are very hot,
00:17:42.410 --> 00:17:45.080
are gonna pass along this way, over here,
00:17:45.080 --> 00:17:47.430
and down the opposite side
00:17:47.430 --> 00:17:49.170
and they're gonna come
all the way down here
00:17:49.170 --> 00:17:52.210
and then we're gonna exhaust
those hot exhaust gases,
00:17:52.210 --> 00:17:54.090
who are now relatively cool,
00:17:54.090 --> 00:17:56.220
to our exhaust gas cleaning system.
00:17:56.220 --> 00:17:58.270
Which we're gonna cover in a later video.
00:17:59.600 --> 00:18:03.193
So our boiler feedwater
has entered through here,
00:18:04.230 --> 00:18:06.130
it's passed through the economizer,
00:18:06.130 --> 00:18:07.790
can see it flowing through here,
00:18:07.790 --> 00:18:11.243
this entire bank of tubes
is known as the economizer,
00:18:12.200 --> 00:18:14.303
and then it's gonna be sent up,
00:18:15.680 --> 00:18:18.190
all the way to our steam drum
00:18:18.190 --> 00:18:20.910
by going along here and across,
00:18:20.910 --> 00:18:22.193
and to our steam drum.
00:18:23.790 --> 00:18:25.410
I'm gonna stop the video at this point
00:18:25.410 --> 00:18:27.230
because round about now,
00:18:27.230 --> 00:18:30.230
we're generating some steam.
00:18:30.230 --> 00:18:33.370
Not much, but that's what the
rest of the boiler is for.
00:18:33.370 --> 00:18:34.490
In our next video,
00:18:34.490 --> 00:18:35.710
we're gonna have a look at
00:18:35.710 --> 00:18:38.780
a coal-fired power plant's steam system.
00:18:38.780 --> 00:18:42.360
But specifically, I'm
gonna spend an entire video
00:18:42.360 --> 00:18:46.303
showing you how a water tube boiler works.
00:18:47.380 --> 00:18:49.700
Hope to see you on the next video!
00:18:49.700 --> 00:18:52.960
If you want to learn even
more about steam systems,
00:18:52.960 --> 00:18:55.500
water tube boilers, fire tube boilers,
00:18:55.500 --> 00:18:57.270
or engineering in general,
00:18:57.270 --> 00:19:00.200
then check out some of
our online video courses.
00:19:00.200 --> 00:19:03.950
We've got over 30 hours of video content.
00:19:03.950 --> 00:19:07.010
And over 25 different courses.
00:19:07.010 --> 00:19:10.170
So if you really want to expand
your engineering knowledge,
00:19:10.170 --> 00:19:13.160
then please do check out
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00:19:13.160 --> 00:19:14.240
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00:19:14.240 --> 00:19:17.020
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00:19:19.620 --> 00:19:21.110
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