FIELD OF THE INVENTION
The present invention relates to a device installed inside a deaerator. In
particular, the present invention relates to a novel device for high dissolved
oxygen venting adaptable to deareators.
BACKGROUND OF THE INVENTION
Deaerator is a direct contact heat exchanger which is used in a steam heating
cycle either in a power plant or in a process steam generating industry.
The input to deaerator is condensate (water) carrying high dissolved oxygen and
traces of carbon dioxide present in the condensate coming from low pressure
heater.

The function of deaerator is to remove these dissolved oxygen and CO2 to a
minimum level (i.e. upto 7 parts per Bilion) so that corrosion does not attack in
the boiler tubes.
Oxygen is removed from condensate (water) in deaerator as shown in Fig. 1.
Water is admitted into the deaerator (1) from the condensate inlet nozzle (10)
on the top of the deaerator.
This condensate in collected in the water box (11) which is a water chamber on
the top of the deaerator.
A plurality of spray valves (3) are mounted in the water chamber (11) and these
nozzles spray the water into a fine jet which again gets divided into fine droplets.
Steam is admitted into deaerator (1) from extraction steam inlet connection (12)
on the first side of deaerator (1). After entering into deaerator (1) from the
bottom of the tray stack (13) mounted in the tray box (14) below the spray
nozzles.
This steam goes up and meets the water sprayed by the spray valves and falling
down on the trays.
In this process steam heats the water to saturation temperature and thereby
reducing the solubility of dissolved oxygen to zero level in water.
Since the solubility has become zero dissolved oxygen cannot stay any longer in
water and comes out of water droplets and gets carried away by steam coming
in the opposite direction.
The same process repeats in the trays also. Here water falls on the trays and fills
each trough of the tray and when it is full, overflows to the trays below.
While falling from the top tray to bottom tray in the tray stack, again water gets
divided into fine droplets, meets steam coming in the opposite direction, gets
heated up this process dissolved oxygen comes out of droplets of water. It is
carried away by steam which goes out of 2 or 3 vents nozzles (8) provided
through the water chamber.
Nearly 90% of deaeration takes place in the spray zone i.e. the space between
spray valves and top tray and 10% of deaeration takes place in the tray zone.
Generally the incoming oxygen levels will be of the order of 42 ppb in normal
deareator which is to be reduced to 7ppb with a deaeration ratio of 42 +7 = 6.
But in case of high make up deaerators with inlet oxygen concentration of the
order of 9800 ppb, the deaeration ratio is 9800 ÷ 7= 1400.
Normally, dissolved oxygen is liberated around the spray nozzles and is collected
by the steam which goes out from the vent nozzles to the atmosphere. To
minimize the loss of steam, an orifice is provided in the vent nozzles to restrict
the loss of quantity of steam to 0.5% of total steam quantity.
Problems faced in the existing system (prior art)
The deaeration system explained above was working alright with low oxygen
levels present in the input, i.e. upto 42 ppb and deaeration ratio of 6. But when

the input deaerator is 100% make up water with inlet oxygen level 9800 ppb,
the present system was unable to deaerate to 7ppb. The maximum oxygen level
that could be achieved was 200 ppb instead of 7ppb required
To come out of the above problem, the inventor emphasizes on a new novel
device vent piping, which was introduced to overcome the existing problem and
to generate the required deaerator 7ppb, dissolved oxygen in deaerator as input
in the spray zone. With the introduction of the invented vent piping system,
required deaeration of 7ppb was achieved.
OBJECTS OF THE INVENTION
It is therefore an object of the present invention to propose a novel device for
high dissolved oxygen venting in deaerator which eliminates the disadvantages
of the existing state of arts.
Another object of the present invention is to propose a novel device for high
dissolved oxygen venting in deaerator which reduces the corrosion of the boiler
tube.
A further object of the present invention is to propose a novel device for high
dissolved oxygen venting in deaerators which reduces chemical dosing like
hydrogen dosing.
An yet further object of the present invention is to propose a novel device for
high dissolved oxygen venting in deaerators which improves the efficiency of the
deaerator from 6 to 1400 deaeration ratio.
SUMMARY OF THE INVENTION
The present invention is provided with a novel device for high dissolve oxygen
venting in deaerator comprises a set of parallel three pipes assembled disposed
at different levels, being interconnected by a small pipe from central pipe to the
outer pipe; one manifold is provided at the connecting junction point of central
pipe which in turn connected to the vent pipe line disposed at the top of the
deaerator; each pipe line is covered with a stainless steel sheets to prevent
water carry over; one supporting means from the water box provided inside the
deaeration to hold firmly the device; characterized in that the device reduces the
liberated oxygen concentration inside the deaerator by providing a means for
escape of the liberated oxygen to go out of deaerator through the vents.
BRIEF DESCRIPTION OF THE INVENTION WITH ACCOMPANYING
DRAWINGS
Fig. 1 shows a schematic view of a deaerator as per prior art.
Fig. 2 shows a schematic view showing the new device installed in the existing
deaerator.
Fig. 3 shows a schematic sketch showing novel device as per invention and the
end view of the device.

Fig. 4 shows a schematic diagram of the novel device covered up with a stainless
steel sheet to prevent water carry over along with steam.
BRIEF DESCRIPTION OF A PREFERRED EMBODIMENT OF THE
INVENTION
The novel device (1) comprises an assembled of three parallel pipes (2,3,4)
disposed at different levels and being interconnected by a small connect pipes
(5,5) from the central pipe (3) to the outer two pipes (2 and 4). The junction
point is provided with a main fold (6) and the manifold is connected the existing
vent nozzles (8). Each pipe is covered up with a stainless steel sheet (7) (Fig.4)
along the configuration of the pipes to prevent water carry over by steam. One
deaerators contains a plurality of such devices according to the requirement of
deaeration ratio and size of the deaerator.
The function of such deaerator incorporating the new device is provide means
for collection dissolve oxygen liberated at every nook and corner of the spray
zone.
Furthermore, to prevent any stagment pockets of oxygen which leads bad
deaeration.

WE CLAIM:
1. A novel device for high dissolve oxygen venting in deaerator comprises:
a set of parallel three pipes assembled disposed at different levels,
being interconnected by a small pipe from central pipe to the outer
pipe;
one manifold is provided at the connecting junction point of central
pipe which in turn connected to the vent pipe line disposed at the
top of the deaerator.
each pipe line is covered with a stainless steel sheets to prevent
water carry over;
one supporting means from the water box provided inside the
deaeration to hold firmly the device;
characterized in that the device reduces the liberated oxygen concentration
inside the deaerator by providing a means for escape of the liberated oxygen to
go out of deaerator through the vents.
2. The device as claimed in claim 1 wherein one deaerator provided with a
plurality of devices according to the size of deaerators.
3. The device as claimed in claim 1 wherein the parallel three pipes are
assembled and welded.
4. The device as claimed in claim 1 wherein the pipes are made of stainless
steel or copper pipe.
5. The device as claimed in claim 1 wherein the support means are steel
plates and pipes assembly.
6. A novel device for high dissolve oxygen venting in deaerator as
substantially described in the specification and illustrated in the accompanying
drawings.

A novel device for high dissolve oxygen venting in deaerator comprises:
a set of parallel three pipes assembled disposed at different levels,
being interconnected by a small pipe from central pipe to the outer
pipe;
one manifold is provided at the connecting junction point of central
pipe which in turn connected to the vent pipe line disposed at the
top of the deaerator.
each pipe line is covered with a stainless steel sheets to prevent
water carry over;
one supporting means from the water box provided inside the
deaeration to hold firmly the device;
characterized in that the device reduces the liberated oxygen concentration
inside the deaerator by providing a means for escape of the liberated oxygen to
go out of deaerator through the vents.