FIELD OF INVENTION:
00001. The present invention relates to an improved process of water treatment in fossil
fuel fired steam generators, and more particularly to a condensate water treatment and stripping
volatile alkalizing chemicals from a steam generating system used for power production where
air cooled condensers are used for steam condensation. The invention disclosed herein, the
alkalizing chemicals such as ammonia can be reused and the steam generating system can be
operated with steam separating device working in subcritical pressure or supercritical pressure.
BACKGROUND OF THE INVENTION:
00002. In a fossil fuel fired power boiler the steam is generated for expanding in the
turbine where the thermal and mechanical energy from the steam is extracted for power
generation. The expanded steam is cooled down to a lowest possible temperature in condenser
and steam condensate is collected in a vessel and mixed with a fresh supply of demineralized
water before pumping back into the boiler through feed water pumps.
00003. Traditionally the condenser used for the steam condensation operate with
treated raw water as a cooling medium which is usually obtained from a natural water body
such as lake, river, canal and deep well etc. Treated raw water with low temperature flows
through a heat exchanger where heat is transferred from the steam phase to raw water resulting
in steam condensation.
00004. The cooling water requirement for condenser operation may vary based on the
degree of cooling down required for steam condensation. Also the configuration of condenser
and cooling water supply may vary based on the operating cost and availability of the cooling
water. The cooling water can be freshly obtained from natural water bodies and used once in
the condenser or it can be recirculated in the cooling process with the help of cooling towers.
00005. In arid locations the availability of boiler feed water is highly critical and hence
a huge requirement of cooling water for steam condensation is highly uneconomical and
2
unsustainable for longer period of steam generating power boilers. But for a power plant
operation the steam condensation is essential for various technical requirement for boiler
efficiency.
00006. Consequently, for steam generating power boilers located in such an arid area
the steam condensation is carried by air cooled condensers where atmospheric air is used as
cooling medium instead of cooling water. The steam is passed through an array of heat
exchangers where air is blown from the opposite side for cooling the steam phase.
00007. Since large surface areas are required for air cooled steam condensers the heat
exchanger is usually made up of aluminum alloy pipes with aluminum alloy based fins. The
steam condensate is collected at the bottom of the air cooled condenser sent further for
condensate polisher followed by feed water system and boiler feed pump.
00008. The air cooled condensers are susceptible to severe corrosion attacks provided
the steam condensate is deprived of alkaline chemical.
00009. But for steam generators the usage of alkaline chemical is to be controlled to a
minimum so as to derive benefits from the latest water treatment practices in which reduction
in water treatment chemical consumption is insisted.
PRIOR ART:
000010. U.S. Patent. No. 4632676 describes a method of stripping of ammonia from
ammoniacal water which is produced in gas cooling process in coking plants. Steam is passed
in countercurrent manner along with ammoniacal water which results in the separation
ammonia from the ammoniacal water. The separated ammonia is brought to reacting with
sulfuric acid for producing ammonium sulphate.
000011. U.S. Patent No. 2500291 describes a method of scrubbing ammonia from
ammoniacal water which is produced in gas cooling process in coking plants. Salts of organic
agents such as quinolone, iso quinolone, methylquinoline etc. are used for scrubbing ammonia
from the ammoniated water. The mixture of organic agents along with ammonia is subjected
to series of distillation process resulting in ammonia separation. The separated ammonia is
brought to reacting with sulfuric acid for producing ammonium sulphate.
3
000012. U.S. Patent No. 3920419 describes a method of removal of ammonia from
ammonia liquor in a packed column by using air as a stripping medium. The ammonia
containing air reacted with sulfuric acid for separating the ammonia from the air.
000013. U.S. Patent No. 3428426 discloses a specific arrangement of vertical column
used for the separation of ammonia stripping from ammonium sulphate solution using hot air,
steam or any other liquid as stripping medium.
000014. U.S. Patent No. 3785121 describes a type of stripping system and cooling
system for separating ammonia from waste water using air as a stripping medium. The patent
discusses about a specific process where both stripping of ammonia and cooling of ammonia
gas is coupled together.
000015. U.S. Patent No. 5203286 discusses a type of apparatus for degassing water with
steam and thereby separating gaseous impurities.
000016. GB Patent No. 2040901 discloses a method of ammonia removal from acid
electrolytes in Fuel Cells by using phosphoric acid as a scrubbing material. The reaction
between phosphoric acid and ammonia results in the formation of a solid product. The solid
product is again contacted with a high concentrated ammonia gas for regenerating phosphoric
acid from the ammonium phosphate beds. Here only the phosphoric acid used for the scrubbing
of ammonia is regenerated for further uses.
000017. Based on the prior art search it is clear that the control of steam condensate pH
and reusing of ammonia for further alkalizing the upcoming steam condensate is not addressed
anywhere for power plant application by removing ammonia from ammoniated steam
condensate by steam stripping.
000018. Hence considering the air cooled condenser, an alkaline chemical is to be dosed
to achieve higher pH in the condenser and thereby controlling the condenser corrosion where
as in the case boiler operation, dosing of alkaline chemical is to be curtailed. The reduction in
alkaline dosing chemical is also better for condenser polishing for its longer run otherwise with
increased chemical loading the condenser polishing unit may exhaust frequently resulting into
the requirement of multiple regenerations which would include high operating costs and
consumable costs.
4
000019. The present invention of condenser water treatment addresses this problem by
implementing alkaline dosing chemical upstream of air cooled condenser and immediate
reclaiming of the same at downstream. In this process the alkaline chemical used for increasing
the steam condensate pH reused within the air cooled condenser system and no additional
chemical is allowed to pass to condensate polishing unit and feed water system.
OBJECTS OF THE INVENTION
000020. It is therefore an object of the present invention is to overcome the shortcomings
of the prior art and to provide an improved process of condensate water treatment by stripping
alkalizing chemicals from steam condensates by using steam as stripping medium in the
downstream of air cooled condensers in subcritical or super critical steam generating power
boilers.
000021. Another object of the present invention is to protect the air cooled condensers
from corrosion damage and the reuse of alkalizing chemical or ammonia reduces chemical
consumption cost for alkalizing chemical procurement.
000022. Yet another object of the present invention is to reduce load on condensate
polishing unit and feed water treatment.
000023. Further object of the present invention is to reduce the consumption of
alkalizing chemical for increasing the pH of input water for air cooled condensers since the
alkalizing chemical is recaptured in the downstream and stored for further use.
000024. Another object of the present invention to provide an amine separating
apparatus for water treatment to condensate water in subcritical or supercritical steam
generating power boilers.
SUMMARY OF THE INVENTION
000025. One or more drawbacks of conventional systems for improved process of water
treatment in fossil fuel fired steam generators are overcome, and additional advantages are
provided through the method as claimed in the present disclosure. Additional features and
5
advantages are realized through the technicalities of the present disclosure. Other embodiments
and aspects of the disclosure are described in details herein and are considered to be part of the
claimed disclosure.
000026. A method to condensate water treatment of fossil fuel fired steam generators in
a steam generating system for power production, said method comprises the steps of:
i) collection of steam from turbine (1) floor and sending the same counter
currently into the upright vessel (7) where the steam condensate is contacted with upcoming
steam;
ii) collection of stripped ammonia and steam mixture in a separate vessel inside
the accumulator and sending it to the condenser for condensation through cooling tubes (4) &
(5);
iii) collection of steam condensate without ammonia at the bottom of the
accumulator (6) and send it to the condensate polishing unit and then to the feed pump;
iv) cooling of ammonia enriched steam condensate by cooling tubes and collecting
in another compartment of the accumulator and sending it to the air cooled condenser (3).
000027. Another aspect of the present invention is to provide an amine separating
apparatus for water treatment to condensate water in subcritical or super critical steam
generating power boilers, said apparatus comprises:
i) turbines (1);
ii) steam inlet to air cooled condenser (2);
iii) air cooled condenser (3);
iv) cooling tubes such as feed cooling tube (4) and return cooling tube (5) for
condensation of stripped ammonia and steam mixture;
v) accumulator (6) placed at the bottom of the upright vessel (7) for collecting the
condensed ammoniated water;
vi) dosing line (8) to air cooled condensers for dosing ammonia;
vii) feed water train (9) and boiler feed pump (10) which also stores the steam
condensate, boiler and super heater and reheaters (11);
viii) condensate pump (12) for pumping the condensed liquid into the feed water
train;
ix) condensate polishing unit (13) placed at bottom of the accumulator (6) for
polishing the condensed liquid collected in accumulator; and
6
x) a high temperature steam line obtained from turbine floor for stripping (14)
wherein the ammonia containing steam condensate is stored from further usage,
so that higher pH can be maintained in the input water to the air cooled condenser and ammonia
dosage also reduces the consumption of ammonia for increasing the pH of input water for air
cooled condenser since ammonia is captured in downstream and subjected for further uses.
000028. Various objects, features, aspects, and advantages of the inventive subject
matter will become more apparent from the following detailed description of preferred
embodiments.
000029. It is to be understood that the aspects and embodiments of the disclosure
described above may be used in any combination with each other. Several of the aspects and
embodiments may be combined to form a further embodiment of the disclosure.
000030. The foregoing summary is illustrative only and is not intended to be in any way
limiting. In addition to the illustrative aspects, embodiments, and features described above,
further aspects, embodiments, and features will become apparent by reference to the drawings
and the following detailed description.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
000031. The illustrated embodiments of the subject matter will be best understood by
reference to the drawings, wherein like parts are designated by like numerals throughout. The
following description is intended only by way of example, and simply illustrates certain
selected embodiments of devices, systems, and processes that are consistent with the subject
matter herein, wherein:
000032. Figure 1 illustrates the arrangement of condensate water treatment in fossil fuel
fired boiler.
000033. The figure depict embodiments of the disclosure for purposes of illustration
only. One skilled in the art will readily recognize from the following description that alternative
7
embodiments of the methods illustrated herein may be employed without departing from the
principles of the disclosure described herein.
DETAILED DESCRIPTION OF THE PRESENT INVENTION
000034. While the embodiments of the disclosure are subject to various modifications
and alternative forms, specific embodiment thereof have been shown by way of the figures and
will be described below. It should be understood, however, that it is not intended to limit the
disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all
modifications, equivalents and alternative falling within the scope of the disclosure.
000035. It is to be noted that a person skilled in the art would be motivated from the
present disclosure to arrive at improved process of water treatment in fossil fuel fired steam
generators. Such a method for evaluating the same may vary based on combination of one or
more ingredients. However, such modifications should be construed within the scope of the
disclosure. Accordingly, the drawings illustrate only those specific details that are pertinent to
understand the embodiments of the present disclosure, so as not to obscure the disclosure with
details that will be clear to those of ordinary skill in the art having benefit of the description
herein.
000036. As used in the description herein and throughout the claims that follow, the
meaning of “a”, “an”, and “the” includes plural reference unless the context clearly dictates
otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on”
unless the context clearly dictates otherwise.
000037. The terms “comprises”, “comprising”, or any other variations thereof used in
the disclosure, are intended to cover a non-exclusive inclusion, such that a method, turbines,
condenser, feed pump, accumulator, upright vessel, cooling line, dosing line, heaters and
reheaters polishing unit, ammonia that comprises a list of components does not include only
those components but may include other components not expressly listed or inherent to such
method, or assembly. In other words, one or more elements in a system or device proceeded
by “comprises…..a “does not, without more constraints, preclude the existence of other
elements or additional elements in the system, apparatus or device.
8
000038. The present disclosure provides a method to condensate water treatment by
stripping ammonia from steam condensates by using steam as stripping medium in the
downstream of air cooled condensers used for power production. The steam generating system
can be operating with steam separating device working in subcritical pressure or supercritical
pressure. In this method, the ammonia containing steam got condensed and the ammoniated
steam condensate can be reused as it goes back to input water for air cooled condenser.
000039. The method comprises the steps of:
i) collection of steam from turbine (1) floor and sending the same counter
currently into the upright vessel (7) where the steam condensate is contacted with upcoming
steam;
ii) collection of stripped ammonia and steam mixture in a separate vessel inside
the accumulator and sending it to the condenser for condensation through cooling tubes (4) &
(5);
iii) collection of steam condensate without ammonia at the bottom of the
accumulator (6) and send it to the condensate polishing unit and then to the feed pump;
iv) cooling of ammonia enriched steam condensate by cooling tubes and collecting
in another compartment of the accumulator and sending it to the air cooled condenser (2);
wherein because rich ammonia content, this steam condensate pH will be higher
and air cooled condenser will work well at this higher pH without any corrosion issues.
000040. In this water treatment process, simple volatile amine or mixture of volatile
amines are used for conditioning the condensate received from the turbines for increasing the
pH to about 9.2.
000041. The volatile amines is dosed upstream of air cooled condenser alongwith
upcoming steam from the turbines.
000042. The volatile amine collected from the return cooling line is sent to the collecting
vessel located in the amine separating apparatus.
000043. Hence the condenser water treatment method discussed is an effective method
for protecting the air cooled condensers from corrosion damage and the reuse of ammonia
9
reduces chemical consumption cost for ammonia procurement. It also reduces load on
condensate polishing unit and feed water treatment.
000044. In accordance to another embodiment of the present invention, there is provided
an amine separating apparatus, which comprises:
i) turbines (1);
ii) steam inlet to air cooled condenser (2);
iii) air cooled condenser (3);
iv) cooling tubes such as feed cooling tube (4) and return cooling tube (5) for
condensation of stripped ammonia and steam mixture;
v) accumulator (6) placed at the bottom of the upright vessel (7) for collecting the
condensed ammoniated water;
vi) dosing line (8) to air cooled condensers for dosing ammonia;
vii) feed water train (9) and boiler feed pump (10) which also stores the steam
condensate, boiler and super heater and reheaters (11);
viii) condensate pump (12) for pumping the condensed liquid into the feed water
train (9);
ix) condensate polishing unit (13) placed at bottom of the accumulator (6) for
polishing the condensed liquid collected in accumulator (6); and
x) a high temperature steam line obtained from turbine floor for stripping (14)
wherein the ammonia containing steam condensate is stored from further usage,
so that higher pH can be maintained in the input water to the air cooled condenser and ammonia
dosage also reduces the consumption of ammonia for increasing the pH of input water for air
cooled condenser since ammonia is captured in downstream and subjected for further uses.
000045. The present invention consists of an upright stripping vessel (7) and an
accumulator (6) at the bottom of the upright vessel for collecting the condensed ammoniated
water. The apparatus is located at the downstream of the air cooled condenser and the ammonia
enriched steam condensate coming from the stripping process is sent to the air cooled
condensers separately for condensing the same. The ammonia containing steam condensate is
stored for further usage by dosing back (8) to the condensate received from the turbine floor so
that higher pH can be maintained in the input water for air cooled condenser. Also this kind of
ammonia dosage reduces the consumption of ammonia for increasing the pH of input water
10
for air cooled condensers since the ammonia is recaptured in the downstream and stored for
further use.
000046. The amine separating apparatus is having parts such as upright vessel for
contacting hot steam with condensed liquid for separating the volatile amine chemical. The
amine separating apparatus also equipped with collecting vessel for condensing the separated
volatile amine chemical. This apparatus is also equipped with cooling line made up of
aluminum alloy after the collecting vessel and a feed cooling line is fitted with the air cooled
condensers for cooling the evaporated volatile amines. The return from the cooling line is set
to attached to the bottom of the collecting vessel. The feed cooling line fitted to the collecting
vessel is joined above the liquid level.
000047. The condensed liquid collected in the collecting vessel is sent to the dosing line
which is connected to the steam inlet for air cooled condensers. The steam inlet for air cooled
condensers is also equipped with an amine dosing set up for making up the losses of volatile
amines during the cooling process.
000048. This amine separating unit is effective in protecting air cooled condenser from
corrosion also protect condensate polisher from excessive ionic loading and further to reduce
the consumption of ammonia as per the latest water treatment guidelines.
000049. Each of the appended claims defines a separate invention, which for
infringement purposes is recognized as including equivalents to the various elements or
limitations specified in the claims. Depending on the context, all references below to the
“invention” may in some cases refer to certain specific embodiments only. In other cases, it will
be recognized that references to the “invention” will refer to subject matter recited in one or
more, but not necessarily all, of the claims.
000050. Groupings of alternative elements or embodiments of the invention disclosed
herein are not to be construed as limitations. Each group member can be referred to and claimed
individually or in any combination with other members of the group or other elements found
herein. One or more members of a group can be included in, or deleted from, a group for reasons
of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written
description of all groups used in the appended claims.
Equivalents:
000051. With respect to the use of substantially any plural and/or singular terms herein,
those having skill in the art can translate from the plural to the singular and/or from the singular
to the plural as is appropriate to the context and/or application. The various singular/plural
permutations may be expressly set forth herein for sake of clarity.
000052. It will be understood by those within the art that, in general, terms used herein,
and especially in the appended claims (e.g., bodies of the appended claims) are generally
intended as “open” terms (e.g., the term “including” should be interpreted as “including but not
limited to”, the term “having” should be interpreted as “having at least”, the term “includes”
should be interpreted as “includes but is not limited to”, etc.). It will be further understood by
those within the art that if a specific number of an introduced claim recitation is intended, such
an intent will be explicitly recited in the claim, and in the absence of such recitation no such
intent is present. For example, as an aid to understanding, the following appended claims may
contain usage of the introductory phrases “at least one” and “one or more” to introduce claim
recitations. However, the use of such phrases should not be construed to imply that the
introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular
claim containing such introduced claim recitation to inventions containing only one such
recitation, even when the same claim includes the introductory phrases “one or more” or “at
least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be
interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite
articles used to introduce claim recitations. In addition, eve it a specific number of an
introduced claim recitation is explicitly recited, those skilled in the art will recognize that such
recitation should typically be interpreted to mean at least the recited number (e.g., the bare
recitation of “two recitations”, without other modifiers, typically means at least two recitations,
or two or more recitations).
000053. The terminology used herein is for the purpose of describing particular
embodiments only and is not intended to be limiting of the present disclosure. It will be
appreciated that several of the above-disclosed and other features and functions, or alternatives
thereof, may be combined into other systems or applications. Various presently unforeseen or

unanticipated alternatives, modifications, variations, or improvements therein may
subsequently be made by those skilled in the art without departing from the scope of the present
disclosure as encompassed by the following claims.
000054. While various aspects and embodiments have been disclosed herein, other
aspects and embodiments will be apparent to those skilled in the art. The various aspects and
embodiments disclosed herein are for purposes of illustration and are not intended to be
limiting, with the true scope and spirit being indicated by the following claims.

We Claim:

1. A method to condensate water treatment of fossil fuel fired steam generators in a steam
generating system for power production, said method comprises the steps of:
i) collection of steam from turbine (1) floor and sending the same counter
currently into the upright vessel (7) where the steam condensate is contacted with upcoming
steam;
ii) collection of stripped ammonia and steam mixture in a separate vessel inside
the accumulator and sending it to the condenser for condensation through cooling tubes (4) &
(5);
iii) collection of steam condensate without ammonia at the bottom of the
accumulator (6) and send it to the condensate polishing unit and then to the feed pump;
iv) cooling of ammonia enriched steam condensate by cooling tubes and collecting
in another compartment of the accumulator and sending it to the air cooled condenser (3).
wherein pH of steam condensate is higher, so that the air-cooled condenser can
work well without any corrosion issues.
2. The method as claimed in claim 1, wherein no volatile amine or mixture of volatile
amines have used for conditioning the condensate.
3. The method as claimed in claim 1, wherein the pH of closed upstream has increased to
9.2.
4. The method as claimed in claim 1, wherein said steam from the turbines is condensed
in the air cooled condenser along with the volatile amine and the condensed liquid is used for
separating the amine from the steam condensate.
5. The method as claimed in claim 1, wherein the volatile amine collected from the return
cooling line is sent to the collecting vessel located in the amine separating apparatus.

6. An amine separating apparatus for water treatment to condensate water in subcritical or
super critical steam generating power boilers, said apparatus comprises:
i) turbines (1);
ii) steam inlet to air cooled condenser (2);
iii) air cooled condenser (3);
iv) cooling tubes such as feed cooling tube (4) and return cooling tube (5) for
condensation of stripped ammonia and steam mixture;
v) accumulator (6) placed at the bottom of the upright vessel (7) for collecting the
condensed ammoniated water;
vi) dosing line (8) to air cooled condensers for dosing ammonia;
vii) feed water train (9) and boiler feed pump (10) which also stores the steam
condensate, boiler and super heater and reheaters (11);
viii) condensate pump (12) for pumping the condensed liquid into the feed water
train (9);
ix) condensate polishing unit (13) placed at bottom of the accumulator (6) for
polishing the condensed liquid collected in accumulator; and
x) a high temperature steam line obtained from turbine floor for stripping (14)
wherein the ammonia containing steam condensate is stored from further usage,
so that higher pH can be maintained in the input water and ammonia dosage also reduces the
consumption of ammonia for increasing the pH of input water for air cooled condenser since
ammonia is captured in downstream and subjected for further uses.
7. The apparatus as claimed in claim 6, where the upright vessel for helps contacting hot
steam with condensed liquid for separating the volatile amine chemical.
8. The apparatus as claimed in claim 6, where the cooling lines are made of aluminium
alloy.
9. The apparatus as claimed in claim 6, wherein the return from the cooling line is set to
attached to the bottom of the collecting vessel.

10. The apparatus as claimed in claim 6, wherein the steam inlet for air cooled condensers
is also equipped with an amine dosing set up for making up the losses of volatile amines during the cooling process.