English language

How to pronounce sparge pipe in English?

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hi john here
in this video we're going to be looking
at the aerators
i'm going to show you three different
data designs
i'll show you all of the connections and
the systems associated with the aerators
i'll explain to you how they work and
then i'll tell you exactly why we have
the aerators
in the first place if you're working in
the power engineering industry
or most industrial settings that use
steam systems
then you're highly likely to encounter a
deaerator
a deaerator has three main purposes
its primary purpose is to release
non-condensable gases
from the boiler feed water its secondary
purpose
is to heat the incoming makeup water
before it's sent to the boiler and to
heat the condensate
that's returned from the steam system
before it's sent back to the boiler
again
its third and final purpose is to allow
us
to store a certain amount of water that
can be sent to the boiler
as the steam demand on the boiler
fluctuates so it gives us a storage
capacity of boiler feed water when we're
talking about non-condensable gases
the two gases that we're most interested
in are oxygen
and carbon dioxide also referred to as
co2
these non-condensable gases are present
in
the boiler feed water and they're
referred to as dissolved
gases because they are dissolved into
the water
the problem with having oxygen in the
boiler feed water
is that it can lead to corrosion the
problem with having carbon dioxide in
the boiler feed water
is that it makes the water more acidic
a typical boiler will use feed water
that has a ph value
of between 8 to 11. so if we have
excess co2 in the feed water we're going
to have feed water with a
lower ph and this is not desired because
it may lead to
corrosion so in order to protect our
boiler and a lot of the
components associated with the boiler
including piping and valves
we need to remove as much oxygen and co2
from the boiler feed water as possible
a typical de-aerator will be designed to
mechanically
remove oxygen down to a level of about
seven parts per billion any oxygen that
remains
after being stripped by the deorator
will be removed
chemically these oxygen scavenging
chemicals are typically sodium sulfite
and hydrazine let's now have a look at
our first derated design
i'll explain to you exactly how it works
and how we can get those non-condensable
gases
out of the boiler feed water and how at
the same time we can
increase the water's temperature in
order that we don't thermal shock the
boiler when we send the feed water
to the boiler so here's our first
3d model of a de-erator i'll do a little
spin so you can
have a look at it you can see it's
horizontally orientated it's actually a
pressure vessel although the pressure
associated with the aerator
is quite low you're looking at about
point five bar which is about seven
psi and the temperature of the d aerator
should be approximately 105 degrees
celsius
or 217 degrees
fahrenheit pressures and temperatures
do vary based upon the data design
let's have a look at the systems that
the aerator is associated with
we can see here we've got a condensate
inlet
this is a return from the steam system
when the steam has done its work and
given up its
heat it's going to condense and we're
going to need to
return that condensate that water
back to the deaerator where we can
increase its temperature again
and remove some of those condensable
gases if they're present
before we send it back to the boiler so
that is a
steam system return or condensate inlet
we have a steam and a gas vent that is
this
connection here although the deorator
is under a very low pressure as i
mentioned before about 0.5 bar or 7 psi
sometimes a little lower than that we
actually have a vent that vents to
atmosphere continuously
and this vent allows us to constantly
vent the non-condensable gases that have
been liberated
from the water it's not possible
to separate the non-condensable gases
from the steam in an efficient
manner so what we do is we actually
allow a bit of the steam
to escape with the non-condensable gases
for this reason you'll often see a
little bit of steam
always escaping the deerata vent
and this is normal you have to be
careful that you don't vent
too much steam because this would be a
waste of energy
but at the same time you also need to
ensure that you're removing all of the
non-condensable
gases if you don't remove all the
non-condensable gases what will actually
happen is you'll have a area inside here
that is full of non-condensable gas or
we'll say air
and this is known as air blanketing if
you have air blanketing
then it is very difficult to reduce the
oxygen and co2 levels
of the water to an acceptable level
let's go over here and have a look at
the next connection
we've got a steam inlet over here we use
the steam
to heat up the water within
the aerator this is low pressure steam
and sometimes in a power station it will
be exhaust steam from the turbine
it is a heat source as we
increase the temperature of the water
inside the de-aerator
the solubility of the condensable gases
the solubility of the dissolved gases
reduces
that means as we increase the
temperature more oxygen is liberated
from the water
and so is more co2 so that's exactly
what we want
so we need to increase the temperature
of the water until we come
close to the saturation temperature of
the water
the saturation temperature is the
boiling point we don't want our water to
boil
because we want to keep it in liquid
form but we do want to get it to within
2 degrees celsius or 2 degrees
fahrenheit
of the boiling point if we can do this
then we are
massively reducing the amount of oxygen
and co2
that will be present in the water and at
the same time
reducing the likelihood of corrosion
because we're removing the
non-condensable
gases over here we have a safety
relief valve we may have a safety relief
valve on the d-rater but you
may also have a water column it really
does depend upon the design
remember dr8s are not operating at very
high pressures
so sometimes the water column will be
sufficient although
many many deeratas do have a safety
relief valve this is definitely not
unusual
so how are we going to liberate those
gases and
also heat up the water well this
uh first design of the aerator
we feed the condensate
and also the make up water sometimes
in through this connection here if we
zoom in
you can see it comes out of a spray
nozzle the spray nozzle will be a spring
loaded spray nozzle normally
manufactured from
stainless steel as the water enters
a water box around here or sometimes
slightly higher up
perhaps this section here the pressure
inside the water box will increase
it will overcome the spring pressure of
the valve and the water will spray out
of this spray nozzle the reason we spray
the water out is because we want to have
a
good contact surface area between the
water
and the steam which is actually filling
up this whole section here
when we have a good contact surface area
between
two phases such as water and steam we
have a very good heat transfer rate
this allows us to quickly heat up the
water
and liberate a lot of those
non-condensable gases very quickly
and they'll accumulate within this dome
here
also this section here is referred to as
a spray shroud
and those non-condensable gases will
then travel through the
vent zoom in over here
they'll travel up and out and through
the vents the vent itself here looks
very large
you can see up in the corner although it
looks
large don't be deceived what you'll
actually have
is a round plate with a hole board in
the middle
and you will use that to restrict the
flow through the vent
this round plate has a hole in the
middle and it's actually referred to as
our orifice
that's just a snazzy engineering word
for hole
and by increasing the size of the hole
in the plate
you can vent more air and steam and if
you reduce the size of the plate then
you will vent
less air and steam so very simple but
also
very effective once we've sprayed the
water
and it's been heated up by the steam the
water will then
drop down through this tray here you can
see that the yellow arrows actually
indicate the steam and steam is
traveling up the water's
coming down and it's going to land
in uh the aerator particularly in this
section
here this is a preheating section
we're heating up the water which will
normally come up to say
a level of around here
and we're heating up that water to
liberate more of the non-condensable
gases but also that is a secondary
function of the aerator we need to
preheat it and get it ready to be fed to
the boiler
the steam connection as you can see over
here it comes down
we have a sparger steam pipe
sometimes people refer to it simply as a
sparge pipe and you can see the steam
will come down here
come along here and we will spread the
steam out
and it's going to come out below the
water level within the feed water tank
and it's going to bubble up through the
water
again heating the water and releasing
some of those
non-condensable gases so that's
essentially
how this type of deorator works
this type of deorator is known as a
spray
type deaerator the reason we have the
baffle plate here is to restrict the
flow slightly
so that we can have the hotter water
coming over
to this side on the right and we call
this side on the right the aeration
section whereas the side on the left is
the preheating section
once the water has been heated and
de-aerated
it's going to come over to this pipe
here
and this connection here is for boiler
feed water
and the water will drop down and go to
our boiler feed water
pumps important to realize here that
condensate from the steam system
is sent to the deaerator but once it's
been
deaerated and heated again it becomes
feed water
make up water which is water we add to
the system to replace any losses we
might have had
is totally untreated it will have high
levels of oxygen and co2
and we need to strip those out once the
make up water
enters the deorator and is treated it
becomes
feed water let's go and have a look at a
slightly different design now
which is a spray scrubber design
so here we have a slightly different
design
let me go in a little bit here and show
you some of the parts
you can see we've got an air and steam
vent same as before
we've got some makeup water coming into
the system now that wasn't shown before
got a safety relief valve
we've got a condensate return
and then we have quite a different setup
inside the dearater which we'll
discuss in a moment and some steam
coming in
as well so some of the design
is quite similar to the dr80 we saw
before but there are some
differences you can see here that we've
got make up water coming
in and it is going into the water box
and as the pressure in the water box
increases the valves are going to
open and the water is going to be
sprayed into the deerata
so that's much the same as what we saw
before
but we can also see that the condensate
is not going into the water box it's
actually just being fed
straight into the deorator now why
would we do this well the reason we do
this
is because makeup water has a high
concentration of oxygen
and co2 depending on where you get the
water from it may be a river
it may be a lake it may be groundwater
it may be city water
and that means we're going to need to
treat that water a lot more than perhaps
the condensate
let's imagine for a moment that our
steam system is
fully enclosed it's totally sealed off
there's no chance of
any oxygen or co2 getting into the
system then we can assume that the
condensate that we send back to the
deorator
is actually quite clean that means it
has
low levels of o2 low levels of co2
because it did not encounter any oxygen
or co2 in the system
so it could not have absorbed any oxygen
or co2
so there's no need to treat that
condensate to the same level
as for the makeup water for example
so that's the reason why the makeup
water will pass through the spray
nozzles
and the condensate will not it will just
be returned to the inside of the
deorator
now that's not to say that we don't need
to do anything with the condensate we
still do
and what we're going to do with it is
still try and liberate any
non-condensable gases
if they are present but we're also going
to heat up that condensate before we
send it back to the boiler
so we have our water that's sprayed out
here this is our makeup water
it's going to fall into this tray here
the condensate comes down as well and
the water this mixture of condensate and
makeup water
will then go into this pipe here and
let's follow the pipe down
you can see it's coming down here down
here
and it's going into this section here
and what we have
is a scrubber this is a spray
scrubber type deerata because of the
scrubber
inside the scrubber we have a steam
inlet
see our steam connection comes down here
and the steam itself will come down here
and it will come
out of these sort of vents or these
little
long holes the grilles maybe we could
call them
steam will come out and it will bubble
through the water
remember the water's draining down here
it's probably going to fill up the
entire
scrubber up to about here the entire
thing is full of water
the steam comes down the fresh steam
heats up the water liberates some of
those non-condensable gases
scrubs it essentially that's what we
refer to as scrubbing
and slowly as the water passes up
through the scrubber the non-condensable
gases will be released
the water will be heated and the steam
will accumulate at the top of the
aerator
in the steam space around here and the
water level will be somewhere around
here so that's a spray scrubber
type deorator once the water's been
heated and the non-condensable gases
have been removed
we can then send the feed water out
through the connection here
and it will go usually to a single or
multi-stage centrifugal pump or series
of pumps
before it's fed to the boiler although
it's not
shown on this model or any of the others
keep in mind
that chemical dosing often occurs in the
deorator
on the makeup water line or after the
deaerator
before the boiler the position of
chemical dosing
really does depend upon the steam system
design for example if you're drawing
makeup water from a reverse osmosis
plant
the water tends to be quite acidic
so you'll need to treat that water
before it comes to the deorator
so you'll add chemical treatment on the
makeup water line
other times it won't be acceptable to
chemically dose
the aerator so you'll dose the boiler
feed water as it comes
out of the deorator but as i mentioned
it really does depend upon the design
but do keep a look out for your chemical
dosing position
because you're highly likely to have one
the dr8 is only going to strip down the
oxygen to seven parts per billion
and you'll need to use oxygen scavenging
chemicals to remove the rest of that
oxygen
co2 is not such a big issue because when
you heat water
close to its saturation temperature or
boiling point
almost all of that co2 is going to be
removed
from the water let's go and have a look
at our final design of the aerator
which is slightly different from the
other two that we've seen thus far
so here's our final design of deerata as
you can see the data
shown looks different to the other two
that we have seen
and this type of deorator is known as a
spray
tray deerata many of the connections are
the same as before
we can see that we've got condensate not
going into the deerata
it's actually going into the feed water
tank
it's important to make a distinction
here between the feed water tank and the
de-aerator
when we have a design like this the
d-rater is actually the
top section the section above the feed
water
tank we de-aerate in this section
once the water drops down into this
holding tank
it becomes feed water and that's why we
call this
our feed water tank i know that might
seem fairly
obvious but a lot of the time when
people talk about the aerators they're
referring
to the entire package the feed water
tank
and the deorator but it's important to
make a distinction between the two
and the deerata is usually mounted above
the feed water
tank although as we've seen it's also
sometimes inside the tank itself
let's have a look at our connections
we've got
make up water this is the water really
does need to be treated as it enters the
system
we've seen that the condensate goes
straight to the feed water tank so it's
most likely a closed
steam system got a relief valve
connection we have a vent
the d-aerator which is the entire piece
we're looking at here
you can see that the water's been
sprayed out into this section
and it's going to land on these trays
here is one tray here is another tray
here is another tray and these top trays
are referred to as heating trays
sometimes you'll actually refer to these
trays as first stage
trays the trays lower down
that would be these ones here these are
referred to as
air separating trays also sometimes
referred to as duration trays
or secondary stage trays we've got an
access door
on the side which allows us to get to
the trays
although it looks slightly small here
and we've got a steam inlet
the steam comes in you can see that
it actually comes in comes down
it'll go around the trays and then it
will come
up and pass through the trays
and it's flowing in a counter
flow direction to the water sometimes
people call counterflow contraflow so
don't be thrown off by that term
so we have a counter or contraflow flow
through the deorato the steam is coming
up the water is coming down
the trays give us a very large contact
surface
area between the water and the steam
that gives us a
high heat transfer rate and allows us to
liberate
a lot of those non-condensable gases
very quickly
whilst also heating up the water believe
it or not about 95
of the non-condensable gases are
actually stripped out in this section
here
with the remainder being removed by the
trays
the trays though are required if we
don't have the trays then we won't be
able to
strip the oxygen down to seven parts per
billion
the non-condensable gases go out through
the vent once again
with a little bit of steam the
deorated water falls into the lower
section here
and it will drop down into this hole
and it will be discharged to the feed
water tank
and the feed water level will be
approximately here which allows us to
maintain
a buffer of steam in the top of the tank
we also have a steam inlet on this side
here
see we've got some low pressure steam or
exhaust steam coming in through the pipe
goes to our steam sparge pipe or sparger
pipe
comes along here and it will bubble up
through the feed water
heating the water up liberating some of
those non-condensable gases again
and then the water is ready to be sent
to
the boiler or specifically the boiler
feed water pumps
if you do have chemical dosing inside
the feed water tank with this design
it is ideal because we've got steam
bubbling up through the water
it agitates the water and this means
that if we add chemicals
inside the feed water tank then those
chemicals are going to mix very
effectively with the water
which means that the chemicals are going
to reliably do their job
there's no point adding chemicals to a
tank that's just completely stationary
and not agitated
because chemicals are not going to mix
properly and they won't work
effectively
once the deo rated and heated up water
is ready it's going to go out through
the exit discharge here
and it will go to the pumps we also have
a drain
on the feed water tank here and we may
need to drain the deorator periodically
perhaps once a year when we do our
boiler inspections
and we will be able to inspect the
inside of the aerator looking for
things like corrosion cracks scale
formation
sedimentation and anything like that
so in summary the aerators are designed
to
liberate non-condensable gases from feed
water
which can cause corrosion in the system
the aerators also increase the
temperature of the feed water
so that we don't thermal shock the
boiler when the water enters the boiler
and finally deorators or specifically
the feed water tank itself
gives us a reserve storage capacity of
water
that we can send to the boiler as steam
demands on the boiler fluctuate
the typical storage capacity for a feed
water tank
is 10 minutes when the boiler is under
full load
there are two main designs of the
aerator these are the spray type
and the tray type de-aerators allow us
to mechanically
remove non-condensable gases from the
feed water
after we've done this we're going to
chemically remove
the remaining oxygen using oxygen
scavengers
these are typically sodium sulfite and
hydrazine
if you like this video then please do
like it or share it on social media we
really do appreciate it
please do subscribe to the youtube
channel and if you want to learn more
about the aerators
then check out our introduction to steam
video course
or our introduction to dr8's video
course
thank you very much for your time and i
hope to see you on another video soon

hi john here

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sparge pipe::noun | Spocien Dictionary

sparge pipe

noun

/spɑrdʒ_paɪp/

a horizontal pipe having fine holes drilled throughout its length so as to deliver a spray of water

Type	Words
Type of	pipage, pipe, piping

How to pronounce sparge pipe in English?

sparge pipe::noun | Spocien Dictionary

abandonment

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