FIELD
5
[001] The present subject matter described herein, in general, relates to an air
conditioning mechanism, and more particularly to a controlled method for
recovering heat from combustion gases or combustible gases generated from the power
generating system, which is otherwise, wasted to the atmosphere and generating cooling
10 effect by utilizing the heat.
BACKGROUND
[002] In a power generating system, after utilization of energy, exorbitant
15 amount of heat is generated by way of fuel combustion or chemical reaction, which if
not utilized is released to the environment as a waste heat. It is often observed that out
of the total heat supplied to the power stations in the form of fuel, approximately, 30 to
40% is converted into useful mechanical work, whereas the remaining heat is expelled
to the environment through exhaust gases and engine cooling systems, resulting in to
20 entropy rise and serious environmental pollution.
[003] These large quantity of hot temperature gases/waste gases are generated
from Boilers, Kilns, Ovens and Furnaces etc., employed in a power generating system.
This high temperature gas can be a flue gas and the like. Besides, the power generating
25 system with steam turbines produce a large amount of flue gas carrying a high
temperature heat. These flue gases are normally exited to the atmosphere from the
power generating system through chimneys, to safe guard other components of power
generating station. Further, the wastage of heat with flue gas also results in lower
overall efficiency of the power generating station.
30
3
[004] Reference is made to a non-patent literature, “Nirmal Sajan et.al, “flue
gas low temperature heat recovery system for air-condition”, IJRET, Volume 04, Issue
4, pp.71-79, April 2015”
(http://esatjournals.org/Volumes/IJRET/2015V04/I04/IJRET20150404013.pdf). The
literature teaches about the mechanism to utilize the waste heat available in exhaus5 t
gases coming out of the Boiler of a thermal power plant. It discloses about the use of
waste heat available to run a Vapour Absorption Refrigeration System which replaces
existing Vapour Compression Refrigeration System which is present in the
administrative block of the plant. It also discloses about replacing Freon-12 refrigerant
10 which causes ozone depletion and to reduce the temperature of exhaust gas emitted to
the atmosphere which causes global warming. However, in the mechanism, the flue gas
(recovered from coal based power-station) is not cooled below 125°C due to limitation
by sulphuric acid dew point.
15 [005] Reference is made to a US Patent publication 8074458 B2, wherein a
heat recovery system for a turbo machine system includes a heat removal system and a
refrigeration system is disclosed. The heat removal system is fluidly connected to at
least one component of the turbo machine system. The heat removal system passes a
cooling fluid through the at least one component to absorb heat. The refrigeration
20 system is operatively connected to the heat removal system. The refrigeration system
extracts the heat from the cooling fluid passing through the at least one component of
the turbo machine system to produce a cooling effect.
[006] The prior art US ‘458 B2 primarily teaches the system for recovering
25 heat from generator and steam turbines. Though the teachings of prior art discloses the
system to recover hear and thereby produce a cooling effect, however, it fails to disclose
about the control of heat recovery to match the cooling load as per the requirement and
seasonal condition.
30 [007] Reference is made to a US Patent publication US 7748210 B2, wherein a
system is provided and includes a first condenser configured to fluidly receive a first
4
steam supply and tower water and to output a first water supply, a second condenser
configured to fluidly receive a first portion of a second steam supply and the first water
supply and to output a second water supply, and a vapor-absorption-machine (VAM)
configured to fluidly receive a second portion of the second steam supply and the
second water supply by which a refrigeration cycle is conducted to thereby cool at leas5 t
one of the tower water and a third water supply used to cool the tower water. However,
the system described in US ‘210requires an optimization in the configuration of
combined cycle power plant. This pose a problem, as the steam cycle of the Gas turbine
HRSG system is changed to run a VAM.
10
[008] Reference is made to a US Patent publication US 8037703 B2, wherein a
heat recovery system is disclosed that includes a source of waste heat, and a
refrigeration system operatively connected to the source of waste heat. The refrigeration
system is capable of extracting heat rejected from the source of waste heat to form a
15 cooling medium. However, the solution is simply directed towards a system in which
heat from condenser of a stream power plant is recovered and not from the flue gas.
[009] Thus, it has been understood that, there exist no considerable solution
which describes a suitable process for recovering heat from a flue gas up to sufficiently
20 low temperature and thereby generating a cooling effect. Accordingly, there exists a dire
need to provide a controlled method for recovering waste heat from a flue gas generated
in a fossil fuel based power generating station and thereby provide means to re-utilize
the said waste heat to generate a cooling effect of a desired temperature.
25 SUMMARY OF THE INVENTION
[0010] The following presents a simplified summary of the invention in order to
provide a basic understanding of some aspects of the invention. This summary is not an
extensive overview of the present invention. It is not intended to identify the key/critical
30 elements of the invention or to delineate the scope of the invention. Its sole purpose is to
5
present some concept of the invention in a simplified form as a prelude to a more
detailed description of the invention presented later.
[0011] An object of the present invention is to provide a controlled method to
recover waste heat from flue gas and generate a cooling effect which matches th5 e
cooling load as per the requirement and seasonal condition.
[0012] Accordingly, in one implementation, the present invention provides a
method for recovering heat from flue gas and generating a cooling effect, said method
10 comprising:
• receiving, by a heat exchanger system, said flue gas produced in a slip
stream duct using one or more variable frequency drive (VFD) fan;
• extracting, by using said heat exchanger system deployed in slip stream,
heat from said flue gas from said slip stream duct, and thereby generating
15 hot fluid at a desired temperature, by passing a cooling fluid through said
heat extracted from said flue gas;
• receiving, by using a vapor absorption system, said hot fluid from said heat
exchanger system, absorbing said heat from said hot fluid to generate a
chilled fluid at a desired temperature for producing a cooling effect.
20
[0013] In one implementation, the method for recovering heat and thereby
generating a cooling effect comprising:
• receiving, by a heat exchanger system, flue gas produced in a slip stream
duct using one or more variable frequency drive (VFD) fan;
25 • extracting, by using said heat exchanger system deployed in slip stream,
heat from said flue gas from said slip stream duct, and thereby generating
hot fluid at a desired temperature, by passing a cooling fluid through said
heat extracted from said flue gas;
6
• receiving, by using a vapor absorption system, said hot fluid from said heat
exchanger system, absorbing said heat from said hot fluid to generate a
chilled water at a desired temperature for producing a cooling effect;
• transferring and controlling said cooling effect by flowing said chilled water
inside a fan coil unit (FCU) to generate cooled air flow to control th5 e
climate of other systems/structures;
• controlling said cooling effect by said cool air flow to a set value by
adjusting said chilled water flow through said fan coil unit (FCU) by
providing a 3-way bypass valve at the inlet of said fan coil unit.
10
[0014] In another implementation, there is provided a method for controlling
changes in the ambient conditions resulted due to day and night climate and/or seasonal
changes during heat recovery in a power generating systems, said method comprising :
i) controlling the generation of cooling effect due to variation in air
15 conditioning load by regulating the chilled water flow using a 3-way valve at
the FCU inlet, resulting in variation of chilled water return temperature to
VAM;
ii) controlling the chilled water temperature at VAM outlet caused due to
variation in chilled water return temperature to VAM as stated in i) by
20 regulating the hot water flow using a 3-way valve at the inlet of VAM
(generator); resulting in variation of hot water return temperature to heat
exchanger, and
iii) controlling the variation in temperature of hot water at heat exchanger outlet
caused due to variation in hot water return temperature to heat exchanger as
25 stated in ii) by regulating the flue gas flow using a VFD driven flue gas
fan.
[0015] By the implementations, the present invention is intended to solve the
problem of recovering heat from flue gas to generate a chilled water for air-conditioning
30 system in accordance with seasonal condition. The method is characterized by the use of
a VFD fan effect for drawing flue gas in a slip stream duct between Induced Draft (ID)
7
fan and exhaust chimney. The VFD fan aims to control the heat recovery to match the
cooling load as per the requirement and seasonal condition.
[0016] Other aspects, advantages, and salient features of the invention will
become apparent to those skilled in the art from the following detailed description5 ,
which, taken in conjunction with the annexed drawings, discloses exemplary
implementations of the invention.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
10
[0017] The above and other aspects, features, and advantages of certain
exemplary implementations of the present invention will be more apparent from the
following description taken in conjunction with the accompanying drawings in which:
15 [0018] Figure 1shows a schematic illustration of a heat recovery system for a
fossil fuel based power generating station in accordance with an implementations of the
invention
[0019] Figure 2 shows a schematic illustration of a heat extraction system
20 portion and an absorption system portion of the heat recovery system.
[0020] Figure 3 shows process flow diagram of operating the air conditioning
system, in accordance with an implementation of the invention.
25 [0021] Figure 4 shows process flow diagram for controlling changes in the
ambient conditions resulted due to day and night climate and seasonal changes during
generation of power in power generating systems, in accordance with another
implementation of the present invention.
8
[0022] Persons skilled in the art will appreciate that elements in the figures are
illustrated for simplicity and clarity and may have not been drawn to scale. For example,
the dimensions of some of the elements in the figure may be exaggerated relative to
other elements to help to improve understanding of various exemplary implementations
of the present disclosure. Throughout the drawings, it should be noted that lik5 e
reference numbers are used to depict the same or similar elements, features, and
structures.
DETAILED DESCRIPTION OF THE PRESENT INVENTION
10
[0023] The following description with reference to the accompanying drawings
is provided to assist in a comprehensive understanding of exemplary implementations of
the invention. It includes various specific details to assist in that understanding but these
are to be regarded as merely exemplary.
15
[0024] Accordingly, those of ordinary skill in the art will recognize that various
changes and modifications of the implementations described herein can be made
without departing from the scope of the invention. In addition, descriptions of wellknown
functions and constructions are omitted for clarity and conciseness.
20
[0025] The terms and words used in the following description and claims are not
limited to the bibliographical meanings, but, are merely used by the inventor to enable a
clear and consistent understanding of the invention. Accordingly, it should be apparent
to those skilled in the art that the following description of exemplary implementations
25 of the present invention are provided for illustration purpose only and not for the
purpose of limiting the invention as defined by the appended claims and their
equivalents.
[0026] It is to be understood that the singular forms “a,” “an,” and “the” include
30 plural referents unless the context clearly dictates otherwise.
9
[0027] By the term “substantially” it is meant that the recited characteristic,
parameter, or value need not be achieved exactly, but that deviations or variations,
including for example, tolerances, measurement error, measurement accuracy
limitations and other factors known to those of skill in the art, may occur in amounts
that do not preclude the effect the characteristic was intended to provide5 .
[0028] Features that are described and/or illustrated with respect to one
implementation may be used in the same way or in a similar way in one or more other
implementations and/or in combination with or instead of the features of the other
10 implementations.
[0029] It should be emphasized that the term “comprises/comprising” when
used in this specification is taken to specify the presence of stated features, integers,
steps or components but does not preclude the presence or addition of one or more other
15 features, integers, steps, components or groups thereof.
[0030] Reference is made to figure 1 that shows a schematic illustration of a
heat recovery system for a fossil fuel based power generating station in accordance with
an implementations of the invention.
20
[0031] Reference is made to figure 2 that shows a schematic illustration of a
heat extraction system portion and an absorption system portion of the heat recovery
system, in accordance with an implementations of the invention.
25 [0032] Reference is made to figure 3 that shows a process flow diagram of
operating the air conditioning system.
[0033] Reference is made to figure 4 that shows process flow diagram for
controlling changes in the ambient conditions resulted due to day and night climate and
30 seasonal changes during generation of power in power generating systems.
10
[0034] In accordance with one implementation of the invention, as shown in
figure 1, the air conditioning system for a fossil fuel based power generating station (27)
includes a heat extraction system (30) and vapor absorption system (8)/vapor absorption
machine (VAM). The fluid in heat extraction system may flow to at least on5 e
component of the fossil fuel based power generating station to extract heat and then this
heated fluid may flow through at least one component of absorption system to release
the heat. The absorption system receives the heat from the heated fluid and generates a
cooling effect. The fluid after releasing the heat in the absorption system may flow back
10 to the heat extraction system.
[0035] In one implementation, the method for recovering heat and thereby
generating air conditioning effect, comprising:
• absorbing, by at least one heat extraction system, heat from one or more
15 component of said fossil fuel fired power generating system. The heat
extraction system further comprises: at least one heat recovery unit
fluidly coupled to at least one discharge of Induced Draught (ID) fan
installed in a slip stream duct of said fossil fuel fired power generating
station, to receive said flue gas;
20 • flowing, by at least one module, one or more fluid through said heat
recovery unit; wherein said heat recovery unit adapted to absorb heat
from said flue gas by means of said fluid passing through said heat
recovery unit, and thereby generating a hot liquid; and
• at least one vapor absorption system operatively coupled to said heat
25 extraction system, said vapor absorption system adapted to receive heat
from said hot liquid from said heat extraction system and thereby
produce a cooling effect.
[0036] In one implementation, the waste heat recovery system of the present
30 invention may be utilized for recovering heat from a large amount of flue gas carrying
heat at preferable temperature of 130°C and above.
11
[0037] As shown in figure 1, a fossil fuel fired power generating system (27)
that may be based on simple Rankine cycle as constructed in accordance with
exemplary implementations. According to the implementation, the power generating
system 27may include a boiler 22, turbine 23, condenser 24, Induced draught (ID) fa5 n
16, chimney 26 and pump 25. All may be fluidly connected. The turbine 23 may
operatively couple to a generator 29 by means of a shaft 28.
[0038] In one implementation, as shown in figure 3, a flue gas is supplied to
10 heat exchanger/heat recovery unit in a slip stream duct following an ID-fan outlet and a
100 TR capacity vapor absorption machine may be connected in closed loop
recirculation system with a hot water pump and associated piping and valves. A flue gas
booster fan with variable frequency drive (VFD)is provided in the bypass duct to
regulate the flue gas flow rate. The heat is transferred from flue gas to generate hot
15 water in the Gas-Water Heat exchanger. The hot water generated may be used to run the
Vapor Absorption Machine. The chilled water generated by VAM is circulated through
FCUs to produce Air-Conditioning in ESP Control Rooms of unit 4, 5, 6, Ash slurry
pump house control room and PLC control cabin of the system. A cooling tower may
also be provided to supply cooling water to condenser of VAM.
20
[0039] In the implementation of waste heat recovery-Air conditioning system,
hot flue Gas containing residual ash in Coal based power plant is utilized to achieve
cooling effect. Flue gas may be drawn in a slip stream duct between Induced Draft (ID)
fan and exhaust chimney using a variable frequency Drive(VFD) Fan. A Gas to water
25 heat exchanger may be placed in the slip stream to recover waste heat from flue gas to
generate hot water. Only partial extraction of desired quantity of waste exhaust gas (by
using VFD fan), from the main duct in a slip stream where heat recovery unit is
installed for producing hot water used for running Vapour Absorption Machine (VAM)
and thereby producing cooling effect. The VFD fan adapted to control the heat recovery
30 to match the cooling load as per the requirement and seasonal condition. By installing
the heat exchanger system in the main flue gas duct then additional power consumption
12
due to pressure drop will be there in all the seasons. The installation of heat exchanger
in slip stream, along with VFD fan ensure optimum power consumption. Thus, this
arrangement may reduce the power consumption to about 0.45kW/TR as compared to
conventional compressor power consumption of about 1 kW/TR. In one application, for
a 100 TR system It has been observed that with the use of variable quantity of flue t5 o
gas, to meet air conditioning requirement, the desired cooling effect in winter require
much lesser power consumption which may be around 11 kW than the power required
during summer while may be around 33kW. In conventional system around 100- 120
kW of power consumption may be obtained when the system is running.
10
[0040] In the implementation, a fossil fuel fired power generating system 27
may further be provided with an air conditioning system comprising a heat extraction
system 30 and vapor absorption system 8. The heat extraction system 30 recovers heat,
typically lost to ambient, from one or more components of fossil fuel fired power
15 generating system 27, such as, but not limited to flue gas exiting to the chimney 26. The
heat may be re-utilized in an absorption system 8 to provide cooling effect which may
be employed for, but not limited to, climate control for other systems/structures of the
power generating system. It is to be understood that the heat extraction system can be
selected from any of the existing heat recovering device and the like, while the vapor
20 absorption system can be selected from any of the existing vapor absorption machines
(VAM) or refrigeration system and the like.
[0041] In the implementation, the heat recovery unit 4 of the heat extraction
system can be fluidly installed in a slip stream after ID fan 16 which may be carrying
25 flue gas to the chimney 26. The heat extraction system includes a module or circuit 9
which flows the fluid through a heat recovery unit 4. It should be understood that the
term “fluid” should be construed to include both liquids and gases. The fluid passing
through heat recovery unit 4 absorbs heat from the flue gas passing to the chimney 26.
More specifically, the fluid passing through heat recovery unit 4 may absorb heat and
13
transforms it into a heated fluid. The heated fluid is utilized by a vapor absorption
system 8 to produce a cooling effect.
[0042] A typical vapor absorption system 8 may comprise a condenser, a
refrigerant generator, an absorber and an evaporator. The evaporator 17 may be fluidl5 y
connected to a chilling coil. The Vapor absorption system 8 may include a cooling
circuit fluidly connecting condenser, absorber and a cooling tower (as shown in figure
3). The cooling circuit may contain a fluid that can serves as a heat sink for the vapor
absorption cycle. The cooling fluid flows through condenser and through piping
10 towards the cooling tower. The fluid flowing from the cooling tower passes through
additional piping and back into absorber before re-entering condenser to take on
additional heat from the heated fluid present within heat extraction system.
[0043] In one application, the vapor absorption system 8, by virtue of absorption
15 cycle operation, may generate a chilled fluid that flows through chilling coil 20 of a Fan
coil unit (FCU). Airflow may pass over the FCU. The airflow loses heat to the cooling
fluid to form a cooling air flow. The cool air flow may then be directed for climate
control of other systems/structures of the power generating system. More specifically,
evaporator 17 is fluidly connected to FCU or chilling coil 20by a chilling
20 circuit/module18. The chilling circuit/module 18 contains a fluid that circulates between
evaporator 17 and chilling coil 20. Airflow passing across chilling coil 20, passes
through chilling circuit/module 18, and loses heat to the cooling fluid within the chilling
circuit/module18. Thus, airflow entering chilling coil 20 or FCU at a temperature, and
exits from said FCU at a temperature lower than the input temperature. The chilled fluid
25 within chilling circuit/module18 may further pass through evaporator 17 to exchange
heat captured from the airflow passing over the chilling coil 20 with refrigerant.
[0044] The chilled water generated by VAM may be circulated through Fan coil
units (FCUs) to produce Air-Conditioning in ESP Control Rooms of unit U # 4, 5, 6,
30 Ash slurry pump house control room and control cabin of the new system. The fan coil
unit may be installed in the control rooms to be air conditioned. The chilled water
14
piping may be connected to the inlet & outlet of fan coil unit. This arrangement does not
require cooling ducts (normally employed in control rooms). A cooling tower may also
be provided to supply cooling water to condenser of VAM.
[0045] In one implementation, as shown in figure 3, the following technica5 l
features may be utilized with the following used with the following specification:
Components Optimum Parameters
Vapor absorption System 100 TR Capacity
Heat extraction system 500 KWth
System Aux power 80 KWe
Flue Gas flow at the rate of 40.5 T/hr , temperature
152°C to 110°C
Hot water flow from heat extraction
system
flow at the rate 42.5 T/hr, temperature
range 80° C-90°C
Cooling water flow flow at the rate 117 T/hr , temperature
range 32°C- 38°C
Chilled water flow from Vapor absorption
System
Flow at the rate of 60 T/hr, temperature
range 7°C -12°C
Heat Exchanger H-finned
Chilling to Electrostatic precipitator
(ESP), CRs unit and ASPH
-NA-
[0046] The control and monitoring of whole system may be from the Operator
10 Work Stations (OWS) located in a cabin near ID-fan area of unit 4. The programmable
logic controller (PLC) control cabinet, VFD panel and electrical panel may also be
located in the cabin. One UPS 240 V AC, 10 amp may be provided for control supply to
PLC and OWS. Binary control i.e., interlock and protection for all auxiliaries and
motorized valves, gate, may be provided in the PLC. Sequence logics are built in the
15 PLC for various modes of operations that may include but not limited to, startup,
15
shutdown, emergency shutdown, changeover to steam heat exchanger based on
measurement, interlock, protection and limits of the system capability.
[0047] As shown in figure 4, , the method for controlling changes in the ambient
conditions resulted due to day and night climate and/or seasonal changes during hea5 t
recovery in a power generating systems. In the implementation, the following
modulating controls are provided in the method:
1. Hot water temperature control: The temperature of hot water at the outlet
of Flue Gas Heat Exchanger is measured by a temperature transmitter
10 and controlled to a set value by controlling the speed of Flue gas fan
VFD i.e adjusting the flow of the flue gas and thereby heat transfer. The
speed of Flue gas fan VFD is controlled by using any of the existing
techniques that may include but not limited to v/f, v/f with encoders,
open loop vectors or close loop vectors or any combination thereof. In
15 Steam heat exchanger mode operation the temperature of the hot water is
controlled by adjusting the steam flow.
2. Chilled water temperature control: The chilled water temperature is
measured at the VAM outlet and controlled to a set value by adjusting
the hot water flow through VAM by a 3-way bypass valve at the inlet of
20 VAM.
3. FCU’s Temperature control: Depending on the load and the temperature
of the room to be air conditioned, the chilled water flow to the FCU shall
be regulated by a controller and 3-way valve located at the inlet of each
FCU. The controller is provided in each ESP Control room and is not
25 controlled through PLC.
[0048] Based on the above it may be understood that the method of the present
invention utilizes heat typically lost from power generating system to provide cool air to
other system components. In this manner, the auxiliary power consumption of power
30 generating system can be reduced. It has been shown that by generating cool air using
an vapor absorption system powered by waste heat, which is otherwise generated using
16
electricity driven vapor compression systems, approximately 0.5 KW/TR (of air
conditioning) of auxiliary power is saved.
[0049] Some of the benefits of the present invention is as follows:
1. Steam cycle of power plant is not modified at all. The flue gas path afte5 r
leaving the boiler is changed to recover heat and thereby to run VAM.
2. The method is characterized by the use of a VFD fan effect for drawing
flue gas in a slip stream duct between Induced Draft (ID) fan and exhaust
chimney. The VFD fan aims to control the heat recovery to match the
10 cooling load as per the requirement and seasonal condition.
3. By installing the heat exchanger system in the main flue gas duct then
additional power consumption due to pressure drop will be there in all
the seasons. The installation of heat exchanger in slip stream, along with
VFD fan ensure optimum power consumption.
15 4. Power Saving upto 55 KWe with respect to Conventional AC systems.
5. Eco friendly system.
[0050] Of course, the above description primarily focuses on the power
generating plant but these concepts are equally applicable to domestic system and other
20 power plant which may be known to generate flue gas into the air.
[0051] Although a controlled method for generating air conditioning effect have
been described in language specific to structural features and/or methods, it is to be
understood that the implementations disclosed in the above system are not necessarily
limited to the specific features or methods or devices described. Rather, the specific
25 features are disclosed as examples of implementations of a controlled method for
generating air conditioning effect.

WE CLAIM:
1. A method for recovering heat and thereby generating a cooling effect, said method
comprising5 :
receiving, by a heat exchanger system, flue gas produced in a slip stream duct using
one or more variable frequency drive (VFD) fan;
extracting, by using said heat exchanger system deployed in slip stream, heat from
said flue gas from said slip stream duct, and thereby generating hot fluid at a
10 desired temperature, by passing a cooling fluid through said heat extracted from
said flue gas;
receiving, by using a vapor absorption system, said hot fluid from said heat
exchanger system, absorbing said heat from said hot fluid to generate a chilled
water at a desired temperature for producing a cooling effect.
15
2. The method as claimed in claim 1, wherein said heat exchanger system deployed in
slip stream duct parallel to a main flue gas duct at the discharge of Induced Draft
(ID) fan.
20 3. The method as claimed in claim 2, wherein said flue gas produced in a slip stream
duct between Induced Draft (ID) fan and exhaust chimney, is received by said using
said variable frequency Drive(VFD) Fan at a desired quantity.
4. The method as claimed in claim 1, wherein temperature of said hot fluid from the
25 outlet of said heat exchanger system is measured by at least one temperature
transmitter, and controlled to a set value by controlling the speed of said VFD fan.
5. The method as claimed in claim 1, wherein temperature of said chilled water is
controlled to a set value by adjusting said hot fluid flow through said vapor
30 absorption system by providing a 3-way bypass valve at the inlet of said vapor
absorption system.
18
6. The method as claimed in claim 1, wherein said vapor absorption system is actuated
by said hot fluid from said heat exchanger system.
7. The method as claimed in claim 1, wherein said chilled water flow produced by sai5 d
vapor absorption system is thereby directed to cool an air flow for climate control of
other systems/structures.
8. The method as claimed in claim 1, wherein said hot fluid from said heat extraction
10 system flow at the rate 42.5 T/hr and at a temperature range 80°C-90°C.
9. The method as claimed in claim 1, wherein said Chilled water from said Vapor
absorption System flow at the rate of 60 T/hr and at a temperature range 7°C -12°C.
15 10. A method for recovering heat and thereby generating a cooling effect, said method
comprising:
receiving, by a heat exchanger system, flue gas produced in a slip stream duct using
one or more variable frequency drive (VFD) fan;
extracting, by using said heat exchanger system deployed in slip stream, heat from
20 said flue gas from said slip stream duct, and thereby generating hot fluid at a
desired temperature, by passing a cooling fluid through said heat extracted from
said flue gas;
receiving, by using a vapor absorption system, said hot fluid from said heat
exchanger system, absorbing said heat from said hot fluid to generate a chilled
25 water at a desired temperature for producing a cooling effect;
transferring and controlling said cooling effect by flowing said chilled water inside
a fan coil unit (FCU) to generate cooled air flow to control the climate of other
systems/structures;
controlling said cooling effect by said cool air flow to a set value by adjusting said
30 chilled water flow through said fan coil unit (FCU) by providing a 3-way bypass
valve at the inlet of said fan coil unit.
19
11. A method for controlling changes in the ambient conditions resulted due to day and
night climate and/or seasonal changes during heat recovery in a power generating
systems, said method comprising :
i) controlling the generation of cooling effect due to variation in ai5 r
conditioning load by regulating the chilled water flow using a 3-way
valve at the FCU inlet, resulting in variation of chilled water return
temperature to VAM;
ii) controlling the chilled water temperature at VAM outlet caused due
10 to variation in chilled water return temperature to VAM as stated in i)
by regulating the hot water flow using a 3-way valve at the inlet of
VAM (generator); resulting in variation of hot water return
temperature to heat exchanger, and
iii) controlling the variation in temperature of hot water at heat
15 exchanger outlet caused due to variation in hot water return
temperature to heat exchanger as stated in ii) by regulating the flue
gas flow using a VFD driven flue gas fan.