Note: Descriptions are shown in the official language in which they were submitted.
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UTILIZATION OF PROCESS HEAT BY-PRODUCT
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority to U.S. Provisional Patent
Application
No. 61/390,397, entitled "Utilizing Waste Heat From R.efineiy Operations" and
filed on
October 6, 2010, in the name of John David Penton et al, the entire disclosure
of which is
hereby fully incorporated herein by reference.
TECHNICAL FIELD
[0002] The present application generally relates to heat recovery and
utilization.
More particularly, the present application relates to the utilization of
process heat by-product
to generate electricity and/or mechanical power.
BACKGROUND
[0003] Objective and regulations surrounding carbon and energy usage has
raised the
importance of designing and retrofitting existing processes for higher levels
of energy
efficiency. The primary driving forces are the need to reduce greenhouse gas
emissions or
local pollution, reducing the energy investment requirement, and best
utilizing existing
supply capacities to improve the access to energy. To increase the energy
efficiency of a
process, it is necessary to improve the utilization of the energy inputted and
reduce the energy
wasted to the atmosphere. One common area of wasted energy is in the heat
exhausted from
sources within the oil and gas industry, from processes such as fluid
catalytic cracking
regenerator column overheads, steam generator exhaust, turbine exhaust, and
other flue gas
sources.
[0004] Currently, methods for recovering higher temperature waste heat
include
utilizing the heat for preheat of other processes or for the production of
steam. This heat can
be utilized in heat recoveiy steam generators or heat exchangers. One such
avenue of
increasing the energy efficiency of a process is to utilize the low
temperature "waste heat",
typically below 500 degrees Fahrenheit ( F), for power generation or
mechanical power. In
geothermal applications and reciprocating engines, an organic Rankine cycle
system is
utilized for the conversion of heat to power. The exhaust gas or brine
exchanges with a
working fluid to produce the desired power output. However, there are
currently several
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drawbacks with utilization of an organic Rankine cycle in a refining process
or various flue
gas exhaust systems. The current technologies have been unable to reach the
necessary
efficiencies at the low temperature ranges of these process streams.
Additionally, current
technologies have been unable to incorporate appropriate exchanger technology
that would
sufficiently decrease fouling and reliability risks in a process with volatile
flowrates and
temperatures. There are also difficulties with structurally integrating the
technology within a
much more complex process setting when compared to the current installations.
[0005]
Therefore, a need exists for a process to effectively and efficiently capture
and
convert this waste heat to a useful energy source.
SUMMARY
[0006] The
present invention is directed to processes for heat recovery from process
heat by-product, wherein such heat recovery is realized by channeling thermal
energy from a
process heat by-product stream to an organic Rankine cycle ......... from
which electricity can be
derived through a turbine-driven generator. The present invention is also
directed to systems
for implementing such processes.
[0007] In one
aspect of the invention, a process for directly utilizing process heat by-
product from refinery operations includes two sub-processes that occur
simultaneously and
that are linked via a heater or heat exchanger. In the first sub-process, a
process heat by-
product stream is directed to a heater and is utilized to heat a working fluid
stream of an
organic Rankine cycle to produce a cooled by-product stream and a heated
working fluid
stream. The cooled by-product stream is then exhausted to atmosphere. In some
instances,
the process heat by-product stream includes flue gas from a fluid catalytic
cracking unit or
recovered heat from a high temperature reactor, such as a fired heater,
incinerator,
hydrotreater, catalytic reformer, or isomerization unit. In the second sub-
process, the
working fluid stream is heated by the process heat by-product stream in the
heater to form. a
heated working fluid stream. In certain aspects, the heated working fluid
stream is vaporized.
The heated working fluid stream is passed through a turbine-generator set to
form an
expanded working fluid stream and produce electricity and/or mechanical power.
The
expanded working fluid stream is then directed to another heat exchanger to
form a
condensed working fluid stream. The condensed working fluid stream is then
passed through
a pump to form the working fluid stream that enters the heater of the organic
Rankine cycle.
[0008] In
another aspect of the invention, a process for directly utilizing waste heat
by-product includes two sub-processes that occur simultaneously and that are
linked via a
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heater or heat exchanger. In the first sub-process, a waste heat by-product
stream is directed
to a heater and is utilized to heat a working fluid stream of an organic
Rankine cycle to
produce a cooled by-product stream and a heated working fluid stream. The
cooled by-
product stream is then exhausted to atmosphere. In certain aspects, the cooled
by-product
stream is directed to an incinerator, a scrubber, or a stack prior to being
exhausted to the
atmosphere. In certain aspects, the process heat by-product stream includes
waste heat from
a steam generator, gas turbine, or diesel generator. In the second sub-
process, the working
fluid stream is heated by the waste heat by-product stream in the heater to
form a heated
working fluid stream. In certain aspects, the heated working fluid stream is
vaporized. The
heated working fluid stream is passed through a turbine-generator set to form
an expanded
working fluid stream and produce electricity and/or mechanical power. The
expanded
working fluid stream is then directed to another heat exchanger to form a
condensed working
fluid stream. The condensed working fluid stream is then passed through a pump
to form the
working fluid stream that enters the heater of the organic Rankine cycle.
[0009] In yet another aspect of the invention, a process for directly
utilizing a heat by-
product stream includes two sub-processes that occur simultaneously and that
are linked via a
heater or heat exchanger. In the first sub-process, a heat by-product stream
is directed to a
heater and is utilized to heat a working fluid stream of an organic Rankine
cycle to produce a
cooled by-product stream and a heated working fluid stream. The cooled by-
product stream
is then exhausted to atmosphere. In certain aspects, the cooled by-product
stream is directed
to an incinerator, a scrubber, or a stack prior to being exhausted to the
atmosphere. In the
second sub-process, the working fluid stream is heated by the heat by-product
stream in the
heater to form a heated working fluid stream. In certain aspects, the heated
working fluid
stream is vaporized. The heated working fluid stream is passed through a
turbine-generator
set to form an expanded working fluid stream and produce electricity and/or
mechanical
power. The expanded working fluid stream is then directed to another heat
exchanger to
form a condensed working fluid stream.
[0010] The features of the present invention will be readily apparent to
those skilled
in the art upon a reading of the description of the preferred embodiments that
follows.
BRIEF DESCRIPTION OF THE, DRAWINGS
[0011] For a more complete understanding of the exemplary embodiments of
the
present invention and the advantages thereof, reference is now made to the
following
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description in conjunction with the accompanying drawings, which are briefly
described as
follows.
[0012] FIG. 1 is a schematic diagram of a heat recovery system for
utilization of
waste heat from a fluid catalytic cracking unit, according to an exemplary
embodiment.
[0013] FIG. 2 is a schematic diagram of a heat recovery system for
utilization of
waste heat from a fluid catalytic cracking unit, according to another
exemplary embodiment.
[0014] FIG. 3 is a schematic diagram of a heat recovery system for
utilization of
waste heat from a fluid catalytic cracking unit, according to yet another
exemplary
embodiment.
[0015] FIG. 4 is a schematic diagram of a heat recovery system for
utilization of
waste heat from a fluid catalytic cracking unit, according to yet another
exemplary
embodiment.
[0016] FIG. 5 is a schematic diagram of a heat recovery system for
utilization of
process heat by-product from a fired heater unit, according to an exemplaiy
embodiment.
[0017] FIG. 6 is a schematic diagram of a heat recovery system for
utilization of
process heat by-product from a fired heater unit, according to another
exemplary
embodiment.
[0018] FIG. 7 is a schematic diagram of a heat recovery system for
utilization of
process heat by-product from a fired heater unit, according to yet another
exemplary
embodiment.
[0019] FIG. 8 is a schematic diagram of a heat recovery system for
utilization of
process heat by-product from a fired heater unit, according to yet another
exemplary
embodiment.
[0020] FIG. 9 is a schematic diagram of a heat recovery system for
utilization of an
exhaust gas stream from a steam generator unit, according to an exemplary
embodiment.
[0021] FIG. 10 is a schematic diagram of a heat recovery system for
utilization of an
exhaust gas stream from a steam generator unit, according to another exemplary
embodiment.
[0022] FIG. 11 is a schematic diagram of a heat recovery system for
utilization of an
exhaust gas stream from a steam generator unit, according to yet another
exemplary
embodiment.
[0023] FIG. 12 is a schematic diagram of a heat recovery system for
utilization of an
exhaust gas stream from a steam generator unit, according to yet another
exemplary
embodiment.
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[0024] FIG. 13 is a schematic diagram of a heat recovery system for
utilization of an
exhaust gas stream from a gas turbine unit, according to an exemplary
embodiment.
[0025] FIG. 14 is a schematic diagram of a heat recovery system for
utilization of an
exhaust gas stream from a gas turbine unit, according to another exemplary
embodiment.
[0026] FIG. 15 is a schematic diagram of a heat recovery system for
utilization of an
exhaust gas stream from a gas turbine unit, according to yet another exemplary
embodiment.
[0027] FIG. 16 is a schematic diagram of a heat recovery system for
utilization of an
exhaust gas stream from a gas turbine unit, according to yet another exemplary
embodiment.
[0028] FIG. 17 is a schematic diagram of a heat recovery system for
utilization of a
process heat stream, according to an exemplary embodiment.
[0029] FIG. 18 is a schematic diagram of a heat recovery system for
utilization of a
process heat stream, according to another exemplary embodiment.
[0030] FIG. 19 is a schematic diagram of a heat recovery system for
utilization of a
process heat stream, according to yet another exemplary embodiment.
[0031] FIG. 20 is a schematic diagram of a heat recovery system for
utilization of a
process heat stream, according to yet another exemplary embodiment.
DETAILED DESCRIPTION
[0032] illustrative embodiments of the invention are described below. In
the interest
of clarity, not all features of an actual implementation are described in this
specification. One
of ordinary skill in the art will appreciate that in the development of any
such actual
embodiment, numerous implementation-specific decisions must be made to achieve
the
developers specific goals, such as compliance with system-related and business-
related
constraints, which will vary from one implementation to another. Moreover, it
will be
appreciated that such a development effort might be complex and time-
consuming, but would
nevertheless be a routine undertaking for those of ordinary skill in the art
having the benefit
of this disclosure.
[0033] The present invention may be better understood by reading the
following
description of non-limitative embodiments with reference to the attached
drawings wherein
like parts of each of the figures are identified by the same reference
characters. The words
and phrases used herein should be understood and interpreted to have a meaning
consistent
with the understanding of those words and phrases by those skilled in the
relevant art. No
special definition of a term or phrase, for example, a definition that is
different from the
ordinary and customary meaning as understood by those skilled in the art, is
intended to be
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implied by consistent usage of the term or phrase herein. To the extent that a
term or phrase
is intended to have a special meaning, for instance, a meaning other than that
understood by
skilled artisans, such a special definition will be expressly set forth in the
specification in a
definitional manner that directly and unequivocally provides the special
definition for the
term or phrase. Moreover, various streams or conditions may be referred to
with terms such
as "hot," "cold," "cooled, "warm," etc., or other like terminology. Those
skilled in the art will
recognize that such terms reflect conditions relative to another process
stream, not an
absolute measurement of any particular temperature.
[0034] FIG. 1 shows a direct heat recovery system 100 for utilization of a
flue gas
stream 102 from a fluid catalytic cracking regenerator unit 101. Generally,
the flue gas
stream 102 is a high temperature heat stream that is generated by the
combustion of coke in
the fluid catalytic cracking regenerator unit 101. In certain embodiments, the
flue gas stream
102 has a temperature in the range of from about 1100 to about 1800 'F. In
certain
exemplary embodiments, when the combustion of coke is complete, at least a
portion 102a of
the flue gas stream 102 enters a waste heat steam generator 103. A boiler feed
water stream
104 also enters the waste heat steam generator 103, and heat from the flue gas
stream 102 is
utilized to heat the boiler feed water stream 104 to produce a steam stream
105. In certain
embodiments, the waste heat steam generator 103 generates steam at pressures
in the range of
from about 15 to about 1100 pound-force per square inch gauge (psig). A
reduced heat flue
gas stream 106 then exits the waste heat steam generator 103 and enters an
electrostatic
precipitator 107, which removes any catalyst fines 108 present in the reduced
heat flue gas
stream 106 to produce a reduced lines flue gas stream 109. In certain
exemplary
embodiments, the reduced fines flue gas stream 109 has a temperature in the
range of from
about 350 to about 800 F.
[0035] In certain embodiments, when the combustion of coke is incomplete
and the
flue gas stream 102 contains significant amounts of carbon monoxide, at least
a portion 102b
of the flue gas stream 102 enters a carbon monoxide boiler 110. A fiiel stream
111 and an air
stream 112 also enter the boiler 110 to combust the carbon monoxide in the
flue gas stream
102. A boiler feed water stream 114 also enters the boiler 110, and heat from
the combustion
process and the flue gas stream 102 is utilized to heat the boiler feed water
stream 114 to
produce a steam stream 115. In certain embodiments, the boiler 110 operates at
a pressure in
the range of from about 15 to about 1100 psig. A reduced heat flue gas stream
116 then exits
the boiler 110 and enters an electrostatic precipitator 117 to remove any
catalyst fines 118
present in the reduced heat flue gas stream 116 to produce a reduced fines
flue gas stream
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119. In certain embodiments, the reduced fines flue gas stream 119 has a
temperature in the
range of from about 350 to about 800 F.
[0036] in certain embodiments, a portion 102a of the flue gas stream 102
can be
routed through the waste heat steam generator 103, and the resulting reduced
fines flue gas
stream 109 can be combined with a remainder portion 102c of the flue gas
stream 102
afterwards prior to entering a heat exchanger 120. The heat exchanger 120 is a
part of the
organic Rankine cycle. The heat exchanger 120 may be ally type of heat
exchanger capable
of transferring heat from one fluid stream to another fluid stream. Suitable
examples of heat
exchangers include, but are not limited to, heaters, vaporizers, economizers,
and other heat
recovery heat exchangers. For example, the heat exchanger 120 may be a shell-
and-tube heat
exchanger, a plate-fin-tube coil type of exchanger, a bare tube or finned tube
bundle, a
welded plate heat exchanger, and the like. Thus, the present invention should
not be
considered as limited to any particular type of heat exchanger unless such
limitations are
expressly set forth in the appended claims. In certain other embodiments, the
flue gas stream
102 can be entirely routed through the waste heat steam generator 103. In
certain alternative
embodiments, a portion 102b of the flue gas stream 102 can be routed through
the through
the boiler 110, and the resulting reduced fines flue gas stream 119 can be
combined with the
remainder portion 102c of the flue gas stream 102 afterwards prior to entering
the heat
exchanger 120. In certain other embodiments, the flue gas stream 102 can be
entirely routed
through the boiler 110. In yet other embodiments, a first portion 102a of the
flue gas stream
102 can be routed through the waste heat steam generator 103, a second portion
102b of the
flue gas stream 102 can be routed through the boiler 110, and the resulting
reduced fines flue
gas streams 109, 119 can be combined with a third portion 102c of the flue gas
stream 102
afterwards prior to entering the heat exchanger 120. In certain other
embodiments, the flue
gas stream 102 can directly enter heat exchanger 120. One having ordinary
skill in the art
will recognize that the flue gas stream 102 can be treated any number of ways
and in any
combination to produce an input flue gas stream 125 prior to entering the heat
exchanger 120.
[0037] At least a portion 125a of the input flue gas stream 125 is then
utilized to heat
a working fluid stream 126 in the heat exchanger 120. The portion 125a of the
input flue gas
stream 125 thermally contacts the working fluid stream 126 to transfer heat to
the working
fluid stream 126. As used herein, the phrase "thermally contact" generally
refers to the
exchange of energy through the process of heat, and does not imply physical
mixing or direct
physical contact of the materials. In certain exemplary embodiments, the
working fluid
stream 126 includes any working fluid suitable for use in an organic Rankine
cycle. The
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portion 125a of the input flue gas stream 125 and the working fluid stream 126
enter the heat
exchanger 120 to produce a heated working fluid stream 128 and a reduced heat
flue gas
stream 129. In certain exemplary embodiments, the working fluid stream 126 has
a
temperature in the range of from about 80 to about 150 'F. In certain
exemplary
embodiments, the heated working fluid stream 128 has a temperature in the
range of from
about 160 to about 450 'F. In certain exemplary embodiments, the heated
working fluid
stream 128 is vaporized. In certain exemplary embodiments, the heated working
fluid stream
128 is vaporized within a supercritical process, with conditions at a
temperature and pressure
above the critical point for the heated working fluid stream 128. In certain
exemplary
embodiments, the heated working fluid stream 128 is superheated. In certain
exemplary
embodiments, the working fluid stream 126 enters as a high pressure liquid and
the heated
working fluid stream 128 exits as a superheated vapor. In certain exemplary
embodiments,
the reduced heat flue gas stream 129 has a temperature in the range of from
about 300 to
about 750 F. In certain embodiments, the reduced heat flue gas stream 129 is
cooled to a
temperature just above its dew point. The reduced heat flue gas stream 129 can
then be
vented to the atmosphere. In certain exemplary embodiments, a portion 125b of
the input
flue gas stream 125 is diverted through a bypass valve 130 and then combined
with the
reduced heat flue gas stream 129 to produce an exhaust flue gas stream 131 to
be vented to
the atmosphere. In certain exemplary embodiments, the exhaust flue gas stream
131 has a
temperature in the range of from about 300 F to about 800 'F. In certain
exemplary
embodiments, the entire portion 125a of the input flue gas stream 125 is
directed through the
heat exchanger 120, and is exhausted to the atmosphere at a temperature of
about 300 'F.
[0038] At least a portion 128a of the heated working fluid stream 128 is
then directed
to a turbine-generator system 150, which is a part of the organic Rankine
cycle. For purposes
of the present application, the term "turbine" will be understood to include
both turbines and
expanders or any device wherein useful work is generated by expanding a high
pressure gas
within the device. The portion 128a of the heated working fluid stream 128 is
expanded in
the turbine-generator system 150 to produce an expanded working fluid stream
151 and
generate power. In certain exemplary embodiments, the expanded working fluid
stream 151
has a temperature in the range of from about 80 to about 440 'F. In certain
embodiments, the
turbine-generator system 150 generates electricity or electrical power. In
certain other
embodiments, the turbine-generator system 150 generates mechanical power. In
certain
embodiments, a portion 128b of the heated working fluid stream 128 is diverted
through a
bypass valve 152 and then combined with the expanded working fluid stream 151
to produce
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an intermediate working fluid stream 155. In certain exemplary embodiments,
the
intermediate working fluid stream 155 has a temperature in the range of from
about 85 to
about 445 F.
[0039] The intermediate working fluid stream 155 is then directed to one
or more air-
cooled condensers 157. The air-cooled condensers 157 are a part of the organic
Rankine
cycle. In certain exemplary embodiments, the organic Rankine cycle includes
two air-cooled
condensers 157 in series. Suitable examples of air-cooled condensers include,
but are not
limited to, air coolers and evaporative coolers. In certain exemplary
embodiments, each of
the air-cooled condensers 157 is controlled by a variable frequency drive 158.
The air-cooled
condensers 157 cool the intermediate working fluid stream 155 to form a
condensed working
fluid stream 159. In certain exemplary embodiments, the condensed working
fluid stream
159 has a temperature in the range of from about 80 to about 150 'F. The
condensed working
fluid stream 159 is then directed to a pump 160. The pump 160 is a part of the
organic
Rankine cycle. The pump 160 may be any type of commercially available pump
sufficient to
meet the pumping requirements of the systems disclosed herein. In certain
exemplary
embodiments, the pump 160 is controlled by a variable frequency drive 161. The
pump 160
returns the condensed working fluid stream 159 to a higher pressure to produce
the working
fluid stream 126 that is directed to the heat exchanger 120.
[0040] FIG. 2 shows a direct heat recovery system 200 according to another
exemplary embodiment. The heat recovery system 200 is the same as that
described above
with regard to heat recovery system 100, except as specifically stated below.
For the sake of
brevity, the similarities will not be repeated hereinbelow. Referring now to
FIG. 2, the
intermediate working fluid stream 155 is then directed to one or more water-
cooled
condensers 257. The water-cooled condensers 257 are a part of the organic
Rankine cycle.
In certain exemplary embodiments, the organic Rankine cycle includes two water-
cooled
condensers 257 in series. The water-cooled condensers 257 cool the
intermediate working
fluid stream 155 to form a condensed working fluid stream 259. In certain
exemplary
embodiments, the condensed working fluid stream 259 has a temperature in the
range of from
about 80 to about 150 F. The condensed working fluid stream 259 is then
directed to the
pump 160 and is returned to a higher pressure to produce the working fluid
stream 126 that is
directed to the heat exchanger 120.
[0041] FIG. 3 shows an indirect heat recovery system 300 for utilization
of an input
flue gas stream 325. The input flue gas stream 325 is the same as that
described above with
regard to input flue gas stream 125, and for the sake of brevity, the
similarities will not be
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repeated hereinbelow. Referring now to FIG. 3, at least a portion 325a of the
input flue gas
stream 325 is utilized to heat a working fluid stream 326 in a heat exchanger
320. The
portion 325a of the input flue gas stream 325 thermally contacts the working
fluid stream 326
and transfers heat to the working fluid stream 326. Suitable examples of the
working fluid
stream 326 include, but are not limited to, water, glycols, therminol fluids,
alkanes, alkenes,
chlorofluorocarbons, hydrofluorocarbons, carbon dioxide (CO2), refrigerants,
and mixtures
of other hydrocarbon components. The portion 325a of the input flue gas stream
325 and the
working fluid stream 326 enter the heat exchanger 320 to produce a heated
working fluid
stream 328 and a reduced heat flue gas stream 329. In certain exemplary
embodiments, the
working fluid stream 326 has a temperature in the range of from about 85 to
about 160 F. In
certain exemplary embodiments, the heated working fluid stream 328 has a
temperature in the
range of from about 165 to about 455 'F. In certain exemplary embodiments, the
reduced
heat flue gas stream 329 has a temperature in the range of from about 300 to
about 750 'F. In
certain embodiments, the reduced heat flue gas stream 329 is cooled to a
temperature just
above its dew point. The reduced heat flue gas stream 329 can then be vented
to the
atmosphere. In certain exemplary embodiments, a portion 325b of the input flue
gas stream
325 is diverted through a bypass valve 330 and then combined with the reduced
heat flue gas
stream 329 to produce an exhaust flue gas stream 331 to be vented to the
atmosphere. In
certain exemplary embodiments, the exhaust flue gas stream 331 has a
temperature in the
range of from about 300 to about 800 'F. In certain exemplary embodiments, the
input flue
gas stream 325 is entirely directed through the heat exchanger 320, and is
exhausted to the
atmosphere at a temperature of about 300 'F.
[0042] A portion 328a of the heated working fluid stream 328 enters a heat
exchanger
335 to heat a working fluid stream 336 to produce a heated working fluid
stream 337 and a
reduced heat working fluid stream 338. The portion 328a of the heated working
fluid stream
328 thermally contacts the working fluid stream 336 and transfers heat to the
working fluid
stream 336. In certain exemplary embodiments, the working fluid stream 336
includes any
working fluid suitable for use in an organic Rankine cycle. In certain
exemplary
embodiments, the working fluid stream 336 has a temperature in the range of
from about 80
to about 150 'F. In certain exemplary embodiments, the heated working fluid
stream 337 has
a temperature in the range of from about 160 to about 450 'F. In certain
exemplary
embodiments, the heated working fluid stream 337 is vaporized. In certain
exemplary
embodiments, the heated working fluid stream 337 is vaporized within a
supercritical
process. In certain exemplary embodiments, the heated working fluid stream 337
is
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superheated. In certain exemplary embodiments, the reduced heat working fluid
stream 338
has a temperature in the range of from about 85 to about 155 'F. In certain
embodiments, a
portion 328b of the heated working fluid stream 328 is diverted through a
bypass valve 339
and then combined with the reduced heat working fluid stream 338 to produce an
intermediate working fluid stream 340. In certain exemplary embodiments, the
intermediate
working fluid stream 340 has a temperature in the range of from about 85 to
about 160 "F.
The intermediate working fluid stream 340 is then directed to a pump 342. In
certain
exemplary embodiments, the pump 342 is controlled by a variable frequency
drive 343. The
pump 342 returns the intermediate working fluid stream 340 to produce the
working fluid
stream 326 that enters the heat exchanger 320.
[0043] At least a portion 337a of the heated worldng fluid stream 337 is
then directed
to a turbine-generator system 350, which is a part of the organic Rankine
cycle. The portion
337a of the heated working fluid stream 337 is expanded in the turbine-
generator system 350
to produce an expanded working fluid stream 351 and generate power. In certain
exemplary
embodiments, the expanded working fluid stream 351 has a temperature in the
range of from
about 80 to about 440 'F. In certain embodiments, the turbine-generator system
350
generates electricity or electrical power. In certain other embodiments, the
turbine-generator
system 350 generates mechanical power. In certain embodiments, a portion 337b
of the
heated working fluid stream 337 is diverted through a bypass valve 352 and
then combined
with the expanded working fluid stream 351 to produce an intermediate working
fluid stream
355. In certain exemplary embodiments, the intermediate working fluid stream
355 has a
temperature in the range of from about 85 to about 445 'F.
[0044] The intermediate working fluid stream 355 is then directed to one
or more air-
cooled condensers 357. The air-cooled condensers 357 are a part of the organic
Rankine
cycle. In certain exemplary embodiments, the organic Rankine cycle includes
two air-cooled
condensers 357 in series. In certain exemplary embodiments, each of the air-
cooled
condensers 357 is controlled by a variable frequency drive 358. The air-cooled
condensers
357 cool the intermediate working fluid stream 355 to form a condensed working
fluid stream
359. In certain exemplary embodiments, the condensed worldng fluid stream 359
has a
temperature in the range of from about 80 to about 150 'F. The condensed
working fluid
stream 359 is then directed to a pump 360. The pump 360 is a part of the
organic Rankine
cycle. In certain exemplary embodiments, the pump 360 is controlled by a
variable
frequency drive 361. The pump 360 returns the condensed working fluid stream
359 to a
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higher pressure to produce the working fluid stream 336 that is directed to
the heat exchanger
335.
[0045] FIG. 4 shows an indirect heat recovery system 400 according to
another
exemplary embodiment. The heat recovery system 400 is the same as that
described above
with regard to heat recovery system 300, except as specifically stated below.
For the sake of
brevity, the similarities will not be repeated hereinbelow. Referring now to
FIG. 4, the
intermediate working fluid stream 355 is directed to one or more water-cooled
condensers
457. The water-cooled condensers 457 are a part of the organic Rankine cycle.
In certain
exemplary embodiments, the organic Rankine cycle includes two water-cooled
condensers
457 in series. The water-cooled condensers 457 cool the intermediate working
fluid stream
355 to form a condensed working fluid stream 459. In certain exemplary
embodiments, the
condensed working fluid stream 459 has a temperature in the range of from
about 80 to about
150 "F. The condensed working fluid stream 459 is then directed to the pump
360 and is
returned to a higher pressure to produce the working fluid stream 336 that is
directed to the
heat exchanger 335.
[0046] Referring now to FIG. 5, a direct heat recovery system 500 for
utilizing heat
from a high temperature reactor, such as a convection section of a fired
heater 502, is shown.
In certain embodiments, the high temperature reactor is an incinerator,
hydrotreater, catalytic
reformer, or isomerization unit. Generally, the fired heater 502 is used in a
refinery to heat a
feedstock stream 503 going to a refinery unit. Suitable examples of refinery
units include,
but are not limited to, crude distillation units and vacuum distillation
units. In certain
embodiments, a fuel stream 505 and an air stream 506 enter a burner section of
the fired
heater 502 and heat the feedstock stream 503 to produce a heated feedstock
stream 507. In
certain embodiments, the heat from the resulting flue gas stream 508 can then
be used to heat
a steam stream 509 to produce a saturated or superheated steam stream 510 and
a flue gas
stream 511. In certain exemplary embodiments, the flue gas stream 511 has a
temperature in
the range of from about 350 to about 800 F.
[0047] The flue gas stream 511 can then be utilized to heat a portion 512a
of a
working fluid stream 512. In certain exemplary embodiments, the working fluid
stream 512
includes any working fluid suitable for use in an organic Rankine cycle. The
flue gas stream
511 and the portion 512a of the working fluid stream 512 enter a heater 513 to
produce a
heated working fluid stream 514 and a reduced heat flue gas stream 515. The
flue gas stream
511 thermally contacts the working fluid stream 512 and transfers heat to the
working fluid
stream 512. The heater 513 is a part of the organic Rankine cycle, and can be
integrated into
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the convection section of the fired heater 502. In certain exemplary
embodiments, the portion
512a of the working fluid stream 512 has a temperature in the range of from
about 80 to
about 150 F. In certain exemplary embodiments, the heated working fluid
stream 514 has a
temperature in the range of from about 160 to about 450 F. In certain
exemplary
embodiments, the heated working fluid stream 514 is vaporized. In certain
exemplary
embodiments, the heated working fluid stream 514 is vaporized within a
supercritical
process. In certain exemplary embodiments, the heated working fluid stream 514
is
superheated. In certain exemplary embodiments, the reduced heat flue gas
stream 515 has a
temperature in the range of from about 300 to about 750 "F. In certain
embodiments, the
reduced heat flue gas stream 515 has a temperature of about 300 F. The
reduced heat flue
gas stream 515 can then be vented to the atmosphere. In certain exemplary
embodiments, a
portion 512b of the working fluid stream 512 is diverted through a bypass
valve 517 and then
combined with the heated working fluid stream 514 to produce a working fluid
stream 518.
In certain exemplary embodiments, the working fluid stream 518 has a
temperature in the
range of from about 155 to about 455 F. In certain exemplary embodiments, the
working
fluid stream 512 is entirely directed through the heater 513.
[0048] At least a portion 518a of the working fluid stream 518 is then
directed to a
turbine-generator system 550 where the portion 518a of the working fluid
stream 518 is
expanded to produce an expanded working fluid stream 551 and generate power.
In certain
exemplary embodiments, the expanded working fluid stream 551 has a temperature
in the
range of from about 80 to about 440 F. In certain embodiments, the turbine-
generator
system 550 generates electricity or electrical power. In certain other
embodiments, the
turbine-generator system 550 generates mechanical power. In certain
embodiments, a portion
518b of the working fluid stream 518 is diverted through a bypass valve 552
and then
combined with the expanded working fluid stream 551 to produce an intermediate
working
fluid stream 555. In certain exemplary embodiments, the intermediate working
fluid stream
555 has a temperature in the range of from about 85 to about 445 'F.
[0049] The intermediate working fluid stream 555 is then directed to one
or more air-
cooled condensers 557. The air-cooled condensers 557 are a part of the organic
Rankine
cycle. In certain exemplary embodiments, the organic Rankine cycle includes
two air-cooled
condensers 557 in series. In certain exemplary embodiments, each of the air-
cooled
condensers 557 is controlled by a variable frequency drive 558. The air-cooled
condensers
557 cool the intermediate working fluid stream 555 to form a condensed working
fluid stream
559. In certain exemplary embodiments, the condensed working fluid stream 559
has a
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temperature in the range of from about 80 to about 150 T. The condensed
working fluid
stream 559 is then directed to a pump 560. The pump 560 is a part of the
organic Rankine
cycle. In certain exemplary embodiments, the pump 560 is controlled by a
variable
frequency drive 561. The pump 560 returns the condensed working fluid stream
559 to a
higher pressure to produce the working fluid stream 512 that is directed to
the heater 513.
[0050] FIG. 6 shows a direct heat recovery system 600 according to another
exemplary embodiment. The heat recovery system 600 is the same as that
described above
with regard to heat recovery system 500, except as specifically stated below.
For the sake of
brevity, the similarities will not be repeated hereinbelow. Referring now to
FIG. 6, the
intermediate working fluid stream 555 is then directed to one or more water-
cooled
condensers 657. The water-cooled condensers 657 are a part of the organic
Rankine cycle.
In certain exemplary embodiments, the organic Rankine cycle includes two water-
cooled
condensers 657 in series. The water-cooled condensers 657 cool the
intermediate working
fluid stream 555 to form a condensed working fluid stream 659. In certain
exemplary
embodiments, the condensed working fluid stream 659 has a temperature in the
range of from
about 80 to about 150 F. The condensed working fluid stream 659 is then
directed to the
pump 560 and is returned to a higher pressure to produce the working fluid
stream 512 that is
directed to the heater 513.
[0051] FIG. 7 shows an indirect heat recovery system 700 for utilization
of a flue gas
stream 711. The flue gas stream 711 is the same as that described above with
regard to flue
gas stream 511, and for the sake of brevity, the similarities will not be
repeated hereinbelow.
Referring now to FIG. 7, the flue gas stream 711 is utilized to heat a working
fluid stream
712 in a heater 713. The flue gas stream 711 thermally contacts the working
fluid stream 712
and transfers heat to the working fluid stream 712. Suitable examples of the
working fluid
stream 712 include, but are not limited to, water, glycols, therminol fluids,
alkanes, alkenes,
chlorofluorocarbons, hydrofluorocarbons, carbon dioxide (CO2), refrigerants,
and mixtures
of other hydrocarbon components. The flue gas stream 711 and the portion 712a
of the
working fluid stream 712 enter the heater 713 to produce a heated working
fluid stream 714
and a reduced heat flue gas stream 715. The heater 713 can be integrated into
the convection
section of a fired heater 702. In certain exemplary embodiments, the portion
712a of the
working fluid stream 712 has a temperature in the range of from about 85 to
about 160 T. In
certain exemplary embodiments, the heated working fluid stream 714 has a
temperature in the
range of from about 165 to about 455 "F. In certain exemplary embodiments, the
reduced
heat flue gas stream 715 has a temperature in the range of from about 300 to
about 750 'F.
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The reduced heat flue gas stream 715 can then be vented to the atmosphere. In
certain
exemplary embodiments, a portion 712b of the working fluid stream 712 is
diverted through
a bypass valve 717 and then combined with the heated working fluid stream 714
to produce a
working fluid stream 718. In certain exemplary embodiments, the working fluid
stream 718
has a temperature in the range of from about 165 to about 455 T. In certain
exemplary
embodiments, the working fluid stream 712 is entirely directed through the
heater 713.
[0052] A portion 718a of the working fluid stream 718 enters a heater 735
to heat a
working fluid stream 736 to produce a heated working fluid stream 737 and a
reduced heat
working fluid stream 738. The portion 718a of the working fluid stream 718
thermally
contacts the working fluid stream 736 and transfers heat to the working fluid
stream 736. In
certain exemplary embodiments, the working fluid stream 736 includes any
working fluid
suitable for use in an organic Rankine cycle. In certain exemplary
embodiments, the working
fluid stream 736 has a temperature in the range of from about 80 to about 150
T. In certain
exemplary embodiments, the heated working fluid stream 737 has a temperature
in the range
of from about 160 to about 450 'F. In certain exemplary embodiments, the
heated working
fluid stream 737 is vaporized. In certain exemplary embodiments, the heated
working fluid
stream 737 is vaporized within a supercritical process. In certain exemplary
embodiments,
the heated working fluid stream 737 is superheated. In certain exemplary
embodiments, the
reduced heat working fluid stream 738 has a temperature in the range of from
about 85 to
about 155 "F. In certain embodiments, a portion 718b of the working fluid
stream 718 is
diverted through a bypass valve 739 and then combined with the reduced heat
working fluid
stream 738 to produce an intermediate working fluid stream 740. In certain
exemplary
embodiments, the intermediate working fluid stream 740 has a temperature in
the range of
from about 85 to about 160 'F. The intermediate working fluid stream 740 is
directed to a
pump 742. In certain exemplary embodiments, the pump 742 is controlled by a
variable
frequency drive 743. The pump 742 returns the intermediate working fluid
stream 740 to
produce the working fluid stream 712 that enters the heater 713.
[0053] At least a portion 737a of the heated working fluid stream 737 is
then directed
to a turbine-generator system 750, which is a part of the organic Rankine
cycle. The portion
737a of the heated working fluid stream 737 is expanded in the turbine-
generator system 750
to produce an expanded working fluid stream 751 and generate power. In certain
exemplary
embodiments, the expanded working fluid stream 751 has a temperature in the
range of from
about 80 to about 440 'F. In certain embodiments, the turbine-generator system
750
generates electricity or electrical power. In certain other embodiments, the
turbine-generator
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system 750 generates mechanical power. In certain embodiments, a portion 737b
of the
heated working fluid stream 737 is diverted through a bypass valve 752 and
then combined
with the expanded working fluid stream 751 to produce an intermediate working
fluid stream
755. In certain exemplary embodiments, the intermediate working fluid stream
755 has a
temperature in the range of from about 80 to about 445 F.
[0054] The intermediate working fluid stream 755 is then directed to one
or more air-
cooled condensers 757. The air-cooled condensers 757 are a part of the organic
Rankine
cycle. In certain exemplary embodiments, the organic Rankine cycle includes
two air-cooled
condensers 757 in series. In certain exemplary embodiments, each of the air-
cooled
condensers 757 is controlled by a variable frequency drive 758. The air-cooled
condensers
757 cool the intermediate working fluid stream 755 to form a condensed working
fluid stream
759. In certain exemplary embodiments, the condensed working fluid stream 759
has a
temperature in the range of from about 80 to about 150 F. The condensed
working fluid
stream 759 is then directed to a pump 760. The pump 760 is a part of the
organic Rankine
cycle. In certain exemplary embodiments, the pump 760 is controlled by a
variable
frequency drive 761. The pump 760 returns the condensed working fluid stream
759 to a
higher pressure to produce the working fluid stream 736 that is directed to
the heater 735.
[0055] FIG. 8 shows an indirect heat recovery system 800 according to
another
exemplary embodiment. The heat recovery system 800 is the same as that
described above
with regard to heat recovery system 700, except as specifically stated below.
For the sake of
brevity, the similarities will not be repeated hereinbelow. Referring now to
FIG. 8, the
intermediate working fluid stream 755 is directed to one or more water-cooled
condensers
857. The water-cooled condensers 857 are a part of the organic Rankine cycle.
In certain
exemplary embodiments, the organic Rankine cycle includes two water-cooled
condensers
857 in series. The water-cooled condensers 857 cool the intermediate working
fluid stream
755 to form a condensed working fluid stream 859. In certain exemplary
embodiments, the
condensed working fluid stream 859 has a temperature in the range of from
about 80 to about
150 F. The condensed working fluid stream 859 is then directed to the pump
760 and is
returned to a higher pressure to produce the working fluid stream 736 that is
directed to the
heater 735.
[0056] Referring now to FIG. 9, a direct heat recovery system 900 for
utilizing a
waste heat by-product stream 901 from a steam generator 902 is shown.
Generally, the steam
generator 902 is used wherever a source of steam is required. In certain
embodiments, a fuel
stream 905 and an air stream 906 enter a burner section 902a of the steam
generator 902 and
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heat a water stream 903 to produce a steam stream 907 and the waste heat by-
product stream
901. In certain exemplary embodiments, the waste heat by-product stream 901
has a
temperature in the range of from about 400 to about 1000
[0057] In certain exemplary embodiments, the waste heat by-product stream
901 is
directed to a diverter valve 908 and can be separated into an exhaust stream
909 and a
discharge stream 910. The discharge stream 910 can be directed to a bypass
stack 911 and
then discharged to the atmosphere. A portion 909a of the exhaust stream 909
can be utilized
to heat a working fluid stream 912. The portion 909a of the exhaust stream 909
thermally
contacts the working fluid stream 912 and transfers heat to the working fluid
stream 912. In
certain exemplary embodiments, the working fluid stream 912 includes any
working fluid
suitable for use in an organic Rankine cycle. The portion 909a of the exhaust
stream 909 and
the working fluid stream 912 enter a heater 913 to produce a heated working
fluid stream 914
and a reduced heat exhaust stream 915. The heater 913 is a part of the organic
Rankine cycle.
In certain exemplary embodiments, the working fluid stream 912 has a
temperature in the
range of from about 80 to about 150 'F. In certain exemplary embodiments, the
heated
working fluid stream 914 has a temperature in the range of from about 160 to
about 450 'F.
In certain exemplary embodiments, the heated working fluid stream 914 is
vaporized. In
certain exemplary embodiments, the heated working fluid stream 914 is
vaporized within a
supercritical process. In certain exemplary embodiments, the heated working
fluid stream
914 is superheated. In certain exemplary embodiments, the reduced heat exhaust
stream 915
has a temperature in the range of from about 300 to about 900 F. The reduced
heat exhaust
stream 915 can then be directed to a primary stack 916 and discharged to the
atmosphere. In
certain exemplary embodiments, the steam generator 902 and the heater 913 can
be integrated
into the primary stack 916. In certain exemplary embodiments, the reduced heat
exhaust
stream 915 can be directed to an incinerator or a scrubber prior to being
discharged to the
atmosphere. In certain exemplary embodiments, a portion 909b of the exhaust
stream 909 is
diverted through a bypass valve 917 and then combined with the reduced heat
exhaust stream
915 to produce an exhaust stream 918. In certain exemplary embodiments, the
exhaust
stream 918 has a temperature in the range of from about 300 to about 905 'F.
In certain
exemplary embodiments, the exhaust stream 909 is entirely directed through the
heater 913.
[0058] At least a portion 914a of the heated working fluid stream 914 is
then directed
to a turbine-generator system 950 where the portion 914a of the heated working
fluid stream
914 is expanded to produce an expanded working fluid stream 951 and generate
power. In
certain exemplary embodiments, the expanded working fluid stream 951 has a
temperature in
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the range of from about 80 to about 440 F. In certain embodiments, a portion
914b of the
heated working fluid stream 914 is diverted through a bypass valve 952 and
then combined
with the expanded working fluid stream 951 to produce an intermediate working
fluid stream
955. In certain exemplary embodiments, the intermediate working fluid stream
955 has a
temperature in the range of from about 80 to about 445 F.
[0059] The intermediate working fluid stream 955 is then directed to one
or more air-
cooled condensers 957. The air-cooled condensers 957 are a part of the organic
Rankine
cycle. In certain exemplary embodiments, the organic Rankine cycle includes
two air-cooled
condensers 957 in series. In certain exemplary embodiments, each of the air-
cooled
condensers 957 is controlled by a variable frequency drive 958. The air-cooled
condensers
957 cool the intermediate working fluid stream 955 to form a condensed working
fluid stream
959. In certain exemplary embodiments, the condensed working fluid stream 959
has a
temperature in the range of from about 80 to about 150 F. The condensed
working fluid
stream 959 is then directed to a pump 960. The pump 960 is a part of the
organic Rankine
cycle. In certain exemplary embodiments, the pump 960 is controlled by a
variable
frequency drive 961. The pump 960 returns the condensed working fluid stream
959 to a
higher pressure to produce the working fluid stream 912 that is directed to
the heater 913.
[0060] FIG. 10 shows a direct heat recovery system 1000 according to
another
exemplary embodiment. The heat recovery system 1000 is the same as that
described above
with regard to heat recovery system 900, except as specifically stated below.
For the sake of
brevity, the similarities will not be repeated hereinbelow. Referring now to
FIG. 10, the
intermediate working fluid stream 955 is then directed to one or more water-
cooled
condensers 1057. The water-cooled condensers 1057 are a part of the organic
Rankine cycle.
In certain exemplary embodiments, the organic Rankine cycle includes two water-
cooled
condensers 1057 in series. The water-cooled condensers 1057 cool the
intermediate working
fluid stream 955 to form a condensed working fluid stream 1059. In certain
exemplary
embodiments, the condensed working fluid stream 1059 has a temperature in the
range of
from about 80 to about 150 F. The condensed working fluid stream 1059 is then
directed to
the pump 960 and is returned to a higher pressure to produce the working fluid
stream 912
that is directed to the heater 913.
[0061] FIG. 11 shows an indirect heat recovery system 1100 for utilization
of an
exhaust stream 1109 from a steam generator 1102. The exhaust stream 1109 is
the same as
that described above with regard to exhaust stream 909, and for the sake of
brevity, the
similarities will not be repeated hereinbelow. A portion 1109a of the exhaust
stream 1109
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can be utilized to heat a working fluid stream 1112. The portion 1109a of the
exhaust stream
1109 thermally contacts the working fluid stream 1112 and transfers heat to
the working fluid
stream 1112. Suitable examples of the working fluid stream 1112 include, but
are not limited
to, water, glycols, therminol fluids, alkanes, alkenes, chlorofluorocarbons,
hydrofluorocarbons, carbon dioxide (CO2), refrigerants, and mixtures of other
hydrocarbon
components. The portion 1109a of the exhaust stream 1109 and the working fluid
stream
1112 enter a heater 1113 to produce a heated working fluid stream 1114 and a
reduced heat
exhaust stream 1115. In certain exemplary embodiments, the working fluid
stream 1112 has
a temperature in the range of from about 85 to about 160 'F. In certain
exemplary
embodiments, the heated working fluid stream 1114 has a temperature in the
range of from
about 165 to about 455 F. In certain exemplary embodiments, the reduced heat
exhaust
stream 1115 has a temperature in the range of from about 300 to about 900 'F.
The reduced
heat exhaust stream 1115 can then be directed to a primary stack 1116 and
discharged to the
atmosphere. In certain exemplary embodiments, the steam generator 1102 and the
heater
1113 can be integrated into the primary stack 1116. In certain exemplary
embodiments, the
reduced heat exhaust stream 1115 can be directed to an incinerator or a
scrubber prior to
being discharged to the atmosphere. In certain exemplary embodiments, a
portion 1109b of
the exhaust stream 1109 is diverted through a bypass valve 1117 and then
combined with the
reduced heat exhaust stream 1115 to produce an exhaust stream 1118. In certain
exemplary
embodiments, the exhaust stream 1118 has a temperature in the range of from
about 300 to
about 905 'F. In certain exemplary embodiments, the exhaust stream 1109 is
entirely
directed through the heater 1113.
[0062] At least a portion 1114a of the heated working fluid stream 1114
enters a
heater 1135 to heat a working fluid stream 1136 to produce a heated working
fluid stream
1137 and a reduced heat working fluid stream 1138. The portion 1114a of the
heated
working fluid stream 1114 thermally contacts the working fluid stream 1136 and
transfers
heat to the working fluid stream 1136. In certain exemplary embodiments, the
working fluid
stream 1136 includes any working fluid suitable for use in an organic Rankine
cycle. In
certain exemplary embodiments, the working fluid stream 1136 has a temperature
in the
range of from about 80 to about 150 'F. In certain exemplary embodiments, the
heated
working fluid stream 1137 has a temperature in the range of from about 160 to
about 450 'F.
In certain exemplary embodiments, the heated working fluid stream 1137 is
vaporized. In
certain exemplary embodiments, the heated working fluid stream 1137 is
vaporized within a
supercritical process. In certain exemplary embodiments, the heated working
fluid stream
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1137 is superheated. In certain exemplary embodiments, the reduced heat
working fluid
stream 1138 has a temperature in the range of from about 85 to about 155 F.
In certain
embodiments, a portion 1114b of the working fluid stream 1114 is diverted
through a bypass
valve 1139 and then combined with the reduced heat working fluid stream 1138
to produce
an intermediate working fluid stream 1140. In certain exemplary embodiments,
the
intermediate working fluid stream 1140 has a temperature in the range of from
about 85 to
about 160 F. The intermediate working fluid stream 1140 is directed to a pump
1142. In
certain exemplary embodiments, the pump 1142 is controlled by a variable
frequency drive
1143. The pump 1142 returns the intermediate working fluid stream 1140 to
produce the
working fluid stream 1112 that enters the heater 1113.
[0063] At least a portion 1137a of the heated working fluid stream 1137 is
then
directed to a turbine-generator system 1150, which is a part of the organic
Rankine cycle.
The portion 1137a of the heated working fluid stream 1137 is expanded in the
turbine-
generator system 1150 to produce an expanded working fluid stream 1151 and
generate
power. In certain exemplary embodiments, the expanded working fluid stream
1151 has a
temperature in the range of from about 80 to about 440 "F. In certain
embodiments, the
turbine-generator system 1150 generates electricity or electrical power. In
certain other
embodiments, the turbine-generator system 1150 generates mechanical power. In
certain
embodiments, a portion 1137b of the heated working fluid stream 1137 is
diverted through a
bypass valve 1152 and then combined with the expanded working fluid stream
1151 to
produce an intermediate working fluid stream 1155. In certain exemplary
embodiments, the
intermediate working fluid stream 1155 has a temperature in the range of from
about 80 to
about 445 "F.
[0064] The intermediate working fluid stream 1155 is then directed to one
or more
air-cooled condensers 1157. The air-cooled condensers 1157 are a part of the
organic
Rankine cycle. In certain exemplary embodiments, the organic Rankine cycle
includes two
air-cooled condensers 1157 in series. In certain exemplary embodiments, each
of the air-
cooled condensers 1157 is controlled by a variable frequency drive 1158. The
air-cooled
condensers 1157 cool the intermediate working fluid stream 1155 to form a
condensed
working fluid stream 1159. In certain exemplary embodiments, the condensed
working fluid
stream 1159 has a temperature in the range of from about 80 to about 150 F.
The condensed
working fluid stream 1159 is then directed to a pump 1160. The pump 1160 is a
part of the
organic Rankine cycle. In certain exemplary embodiments, the pump 1160 is
controlled by a
variable frequency drive 1161. The pump 1160 returns the condensed working
fluid stream
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1159 to a higher pressure to produce the working fluid stream 1136 that is
directed to the
heater 1135.
[0065] FIG. 12 shows an indirect heat recovery system 1200 according to
another
exemplary embodiment. The heat recovery system 1200 is the same as that
described above
with regard to heat recovery system 1100, except as specifically stated below.
For the sake of
brevity, the similarities will not be repeated hereinbelow. Referring now to
FIG. 12, the
intermediate working fluid stream 1155 is directed to one or more water-cooled
condensers
1257. The water-cooled condensers 1257 are a part of the organic Rankine
cycle. In certain
exemplary embodiments, the organic Rankine cycle includes two water-cooled
condensers
1257 in series. The water-cooled condensers 1257 cool the intermediate working
fluid stream
1155 to form a condensed working fluid stream 1259. In certain exemplary
embodiments,
the condensed working fluid stream 1259 has a temperature in the range of from
about 80 to
about 150 T. The condensed working fluid stream 1259 is then directed to the
pump 1160
and is returned to a higher pressure to produce the working fluid stream 1136
that is directed
to the heater 1135.
[0066] Referring now to FIG. 13, a direct heat recovery system 1300 for
utilizing a
waste heat by-product stream 1301 from a gas turbine 1302 is shown. In certain
alternative
embodiments, the gas turbine is replaced with a diesel generator (not shown).
In certain
embodiments, a fuel stream 1305 and an air stream 1306 enter the gas turbine
1302 and is
combusted to produce energy and the waste heat by-product stream 1301. In
certain
exemplary embodiments, the waste heat by-product stream 1301 has a temperature
in the
range of from about 450 to about 1400 F.
[0067] In certain exemplary embodiments, the waste heat by-product stream
1301 is
directed to a diverter valve 1308 and can be separated into an exhaust stream
1309 and a
discharge stream 1310. The discharge stream 1310 can be directed to a bypass
stack 1311
and then discharged to the atmosphere. A portion 1309a of the exhaust stream
1309 can be
utilized to heat a working fluid stream 1312. The portion 1309a of the exhaust
stream 1309
thermally contacts the working fluid stream 1312 and transfers heat to the
working fluid
stream 1312. In certain exemplary embodiments, the working fluid stream 1312
includes any
working fluid suitable for use in an organic Rankine cycle. The portion 1309a
of the exhaust
stream 1309 and the working fluid stream 1312 enter a heater 1313 to produce a
heated
working fluid stream 1314 and a reduced heat exhaust stream 1315. The heater
1313 is a part
of the organic Rankine cycle. In certain exemplary embodiments, the working
fluid stream
1312 has a temperature in the range of from about 80 to about 150 'F. In
certain exemplary
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embodiments, the heated working fluid stream 1314 has a temperature in the
range of from
about 160 to about 450 F. In certain exemplary embodiments, the heated
working fluid
stream 1314 is vaporized. In certain exemplary embodiments, the heated working
fluid
stream 1314 is vaporized within a supercritical process. In certain exemplary
embodiments,
the heated working fluid stream 1314 is superheated. In certain exemplary
embodiments, the
reduced heat exhaust stream 1315 has a temperature in the range of from about
250 to about
1000 GE The reduced heat exhaust stream 1315 can then be directed to a primary
stack 1316
and discharged to the atmosphere. In certain exemplary embodiments, the
reduced heat
exhaust stream 1315 can be directed to an incinerator or a scrubber prior to
being discharged
to the atmosphere. In certain exemplary embodiments, a portion 1309b of the
exhaust stream
1309 is diverted through a bypass valve 1317 and then combined with the
reduced heat
exhaust stream 1315 to produce an exhaust stream 1318. In certain exemplary
embodiments,
the exhaust stream 1318 has a temperature in the range of from about 250 to
about 1100 "F.
In certain exemplary embodiments, the exhaust stream 1309 is entirely directed
through the
heater 1313.
[0068] At least a portion 1314a of the heated working fluid stream 1314 is
then
directed to a turbine-generator system 1350 where the portion 1314a of the
heated working
fluid stream 1314 is expanded to produce an expanded working fluid stream 1351
and
generate power. In certain exemplary embodiments, the expanded working fluid
stream 1351
has a temperature in the range of from about 80 to about 440 "F. In certain
embodiments, a
portion 1314b of the heated working fluid stream 1314 is diverted through a
bypass valve
1352 and then combined with the expanded working fluid stream 1351 to produce
an
intermediate working fluid stream 1355. In certain exemplary embodiments, the
intermediate
working fluid stream 1355 has a temperature in the range of from about 80 to
about 445 F.
[0069] The intermediate working fluid stream 1355 is then directed to one
or more
air-cooled condensers 1357. The air-cooled condensers 1357 are a part of the
organic
Rankine cycle. In certain exemplary embodiments, the organic Rankine cycle
includes two
air-cooled condensers 1357 in series. In certain exemplary embodiments, each
of the air-
cooled condensers 1357 is controlled by a variable frequency drive 1358. The
air-cooled
condensers 1357 cool the intermediate working fluid stream 1355 to form a
condensed
working fluid stream 1359. In certain exemplary embodiments, the condensed
working fluid
stream 1359 has a temperature in the range of from about 80 to about 150 F.
The condensed
working fluid stream 1359 is then directed to a pump 1360. The pump 1360 is a
part of the
organic Rankine cycle. In certain exemplary embodiments, the pump 1360 is
controlled by a
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variable frequency drive 1361. The pump 1360 returns the condensed working
fluid stream
1359 to a higher pressure to produce the working fluid stream 1312 that is
directed to the
heater 1313.
[0070] FIG. 14 shows a direct heat recovery system 1400 according to
another
exemplary embodiment. The heat recovery system 1400 is the same as that
described above
with regard to heat recovery system 1300, except as specifically stated below.
For the sake of
brevity, the similarities will not be repeated hereinbelow. Referring now to
FIG. 14, the
intermediate working fluid stream 1355 is then directed to one or more water-
cooled
condensers 1457. The water-cooled condensers 1457 are a part of the organic
Rankine cycle.
In certain exemplary embodiments, the organic Rankine cycle includes two water-
cooled
condensers 1457 in series. The water-cooled condensers 1457 cool the
intermediate working
fluid stream 1355 to form a condensed working fluid stream 1459. In certain
exemplary
embodiments, the condensed working fluid stream 1459 has a temperature in the
range of
from about 80 to about 150 F. The condensed working fluid stream 1459 is then
directed to
the pump 1360 and is returned to a higher pressure to produce the working
fluid stream 1312
that is directed to the heater 1313.
[0071] FIG. 15 shows an indirect heat recovery system 1500 for utilization
of an
exhaust stream 1509. The exhaust stream 1509 is the same as that described
above with
regard to exhaust stream 1309, and for the sake of brevity, the similarities
will not be
repeated hereinbelow. A portion 1509a of the exhaust stream 1509 can be
utilized to heat a
working fluid stream 1512. The portion 1509a of the exhaust stream 1509
thermally contacts
the working fluid stream 1512 and transfers heat to the working fluid stream
1512. Suitable
examples of the working fluid stream 1512 include, but are not limited to,
water, glycols,
therminol fluids, alkanes, alkenes, chlorofluorocarbons, hydrofluorocarbons,
carbon dioxide
(CO2), refrigerants, and mixtures of other hydrocarbon components. The portion
1509a of
the exhaust stream 1509 and the working fluid stream 1512 enter a heater 1513
to produce a
heated working fluid stream 1514 and a reduced heat exhaust stream 1515. In
certain
exemplary embodiments, the working fluid stream 1512 has a temperature in the
range of
from about 85 to about 160 F. In certain exemplary embodiments, the heated
working fluid
stream 1514 has a temperature in the range of from about 165 to about 455 'F.
In certain
exemplary embodiments, the reduced heat exhaust stream 1515 has a temperature
in the
range of from about 250 to about 1000 'F. The reduced heat exhaust stream 1515
can then be
directed to a primary stack 1516 and discharged to the atmosphere. In certain
exemplary
embodiments, the reduced heat exhaust stream 1515 can be directed to an
incinerator or a
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scrubber prior to being discharged to the atmosphere. In certain exemplary
embodiments, a
portion 1509b of the exhaust stream 1509 is diverted through a bypass valve
1517 and then
combined with the reduced heat exhaust stream 1515 to produce an exhaust
stream 1518. In
certain exemplary embodiments, the exhaust stream 1518 has a temperature in
the range of
from about 250 to about 1100 F. In certain exemplary embodiments, the exhaust
stream
1509 is entirely directed through the heater 1513.
[0072] At least a portion 1514a of the heated working fluid stream 1514
enters a
heater 1535 to heat a working fluid stream 1536 to produce a heated working
fluid stream
1537 and a reduced heat working fluid stream 1538. The portion 1514a of the
heated
working fluid stream 1514 thermally contacts the working fluid stream 1536 and
transfers
heat to the working fluid stream 1536. In certain exemplary embodiments, the
working fluid
stream 1536 includes any working fluid suitable for use in an organic Rankine
cycle. In
certain exemplary embodiments, the working fluid stream 1536 has a temperature
in the
range of from about 80 to about 150 F. In certain exemplary embodiments, the
heated
working fluid stream 1537 has a temperature in the range of from about 160 to
about 450 'F.
In certain exemplary embodiments, the heated working fluid stream 1537 is
vaporized. In
certain exemplary embodiments, the heated working fluid stream 1537 is
vaporized within a
supercritical process. In certain exemplary embodiments, the heated working
fluid stream
1537 is superheated. In certain exemplary embodiments, the reduced heat
working fluid
stream 1538 has a temperature in the range of from about 85 to about 155 "F.
In certain
embodiments, a portion 1514b of the working fluid stream 1514 is diverted
through a bypass
valve 1539 and then combined with the reduced heat working fluid stream 1538
to produce
an intermediate working fluid stream 1540. In certain exemplary embodiments,
the
intermediate working fluid stream 1540 has a temperature in the range of from
about 85 to
about 160 F. The intermediate working fluid stream 1540 is directed to a pump
1542. In
certain exemplary embodiments, the pump 1542 is controlled by a variable
frequency drive
1543. The pump 1542 returns the intermediate working fluid stream 1540 to
produce the
working fluid stream 1512 that enters the heater 1513.
[0073] At least a portion 1537a of the heated working fluid stream 1537 is
then
directed to a turbine-generator system 1550, which is a part of the organic
Rankine cycle.
The portion 1537a of the heated working fluid stream 1537 is expanded in the
turbine-
generator system 1550 to produce an expanded working fluid stream 1551 and
generate
power. In certain exemplary embodiments, the expanded working fluid stream
1551 has a
temperature in the range of from about 80 to about 440 F. In certain
embodiments, the
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turbine-generator system 1550 generates electricity or electrical power. In
certain other
embodiments, the turbine-generator system 1550 generates mechanical power. In
certain
embodiments, a portion 1537b of the heated working fluid stream 1537 is
diverted through a
bypass valve 1552 and then combined with the expanded working fluid stream
1551 to
produce an intermediate working fluid stream 1555. In certain exemplary
embodiments, the
intermediate working fluid stream 1555 has a temperature in the range of from
about 80 to
about 445 cf.
[0074] The intermediate working fluid stream 1555 is then directed to one
or more
air-cooled condensers 1557. The air-cooled condensers 1557 are a part of the
organic
Rankine cycle. In certain exemplary embodiments, the organic Rankine cycle
includes two
air-cooled condensers 1557 in series. In certain exemplary embodiments, each
of the air-
cooled condensers 1557 is controlled by a variable frequency drive 1558. The
air-cooled
condensers 1557 cool the intermediate working fluid stream 1555 to form a
condensed
working fluid stream 1559. In certain exemplary embodiments, the condensed
working fluid
stream 1559 has a temperature in the range of from about 80 to about 150 'F.
The condensed
working fluid stream 1559 is then directed to a pump 1560. The pump 1560 is a
part of the
organic Rankine cycle. In certain exemplary embodiments, the pump 1560 is
controlled by a
variable frequency drive 1561. The pump 1560 returns the condensed working
fluid stream
1559 to a higher pressure to produce the working fluid stream 1536 that is
directed to the
heater 1535.
[0075] FIG. 16 shows an indirect heat recovery system 1600 according to
another
exemplary embodiment. The heat recovery system 1600 is the same as that
described above
with regard to heat recovery system 1500, except as specifically stated below.
For the sake of
brevity, the similarities will not be repeated hereinbelow. Referring now to
FIG. 16, the
intermediate working fluid stream 1555 is directed to one or more water-cooled
condensers
1657. The water-cooled condensers 1657 are a part of the organic Rankine
cycle. In certain
exemplary embodiments, the organic Rankine cycle includes two water-cooled
condensers
1657 in series. The water-cooled condensers 1657 cool the intermediate working
fluid stream
1555 to form a condensed working fluid stream 1659. In certain exemplary
embodiments,
the condensed working fluid stream 1659 has a temperature in the range of from
about 80 to
about 150 'F. The condensed working fluid stream 1659 is then directed to the
pump 1560
and is returned to a higher pressure to produce the working fluid stream 1536
that is directed
to the heater 1535.
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[0076] Referring now to FIG. 17, a direct heat recovery system 1700 for
utilizing a
heat by-product stream 1701 from a process column 1702 is shown. Suitable
examples of
process columns include, but are not limited to, distillation columns and
strippers. In certain
exemplary embodiments, the heat by-product stream 1701 has a temperature in
the range of
from about 170 to about 700 F. A portion 1701a of the heat by-product stream
1701 can be
utilized to heat a working fluid stream 1712. The portion 1701a of the heat by-
product
stream 1701 thermally contacts the working fluid stream 1712 and transfers
heat to the
working fluid stream 1712. In certain exemplary embodiments, the working fluid
stream
1712 includes any working fluid suitable for use in an organic Rankine cycle.
The portion
1701a of the heat by-product stream 1701 and the working fluid stream 1712
enter a heater
1713 to produce a heated working fluid stream 1714 and a reduced heat exhaust
stream 1715.
The heater 1713 is a part of the organic Rankine cycle. In certain exemplary
embodiments,
the working fluid stream 1712 has a temperature in the range of from about 80
to about 150
GE In certain exemplary embodiments, the heated working fluid stream 1714 has
a
temperature in the range of from about 160 to about 450 F. In certain
exemplary
embodiments, the heated working fluid stream 1714 is vaporized. In certain
exemplary
embodiments, the heated working fluid stream 1714 is vaporized within a
supercritical
process. In certain exemplary embodiments, the heated working fluid stream
1714 is
superheated. In certain exemplary embodiments, the reduced heat exhaust stream
1715 has a
temperature in the range of from about 90 to about 500 F. The reduced heat
exhaust stream
1715 can then be vented to the atmosphere. In certain exemplary embodiments, a
portion
170 lb of the heat by-product stream 1701 is diverted through a bypass valve
1717 and then
combined with the reduced heat exhaust stream 1715 to produce an exhaust
stream 1718. In
certain exemplary embodiments, the exhaust stream 1718 has a temperature in
the range of
from about 90 to about 510 F. In certain exemplary embodiments, the heat by-
product
stream 1701 is entirely directed through the heater 1713.
[0077] At least a portion 1714a of the heated working fluid stream 1714 is
then
directed to a turbine-generator system 1750 where the portion 1714a of the
heated working
fluid stream 1714 is expanded to produce an expanded working fluid stream 1751
and
generate power. In certain exemplary embodiments, the expanded working fluid
stream 1751
has a temperature in the range of from about 80 to about 440 'F. In certain
embodiments, a
portion 1714b of the heated working fluid stream 1714 is diverted through a
bypass valve
1752 and then combined with the expanded working fluid stream 1751 to produce
an
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intermediate working fluid stream 1755. In certain exemplary embodiments, the
intermediate
working fluid stream 1755 has a temperature in the range of from about 80 to
about 455 T.
[0078] The intermediate working fluid stream 1755 is then directed to one
or more
air-cooled condensers 1757. The air-cooled condensers 1757 are a part of the
organic
Rankine cycle. In certain exemplary embodiments, the organic Rankine cycle
includes two
air-cooled condensers 1757 in series. In certain exemplary embodiments, each
of the air-
cooled condensers 1757 is controlled by a variable frequency drive 1758. The
air-cooled
condensers 1757 cool the intermediate working fluid stream 1755 to form a
condensed
working fluid stream 1759. In certain exemplary embodiments, the condensed
working fluid
stream 1759 has a temperature in the range of from about 80 to about 150 F.
The condensed
working fluid stream 1759 is then directed to a pump 1760. The pump 1760 is a
part of the
organic Rankine cycle. In certain exemplary embodiments, the pump 1760 is
controlled by a
variable frequency drive 1761. The pump 1760 returns the condensed working
fluid stream
1759 to a higher pressure to produce the working fluid stream 1712 that is
directed to the
heater 1713.
[0079] FIG. 18 shows a direct heat recovery system 1800 according to
another
exemplary embodiment. The heat recovery system 1800 is the same as that
described above
with regard to heat recovery system 1700, except as specifically stated below.
For the sake of
brevity, the similarities will not be repeated hereinbelow. Referring now to
FIG. 18, the
intermediate working fluid stream 1755 is then directed to one or more water-
cooled
condensers 1857. The water-cooled condensers 1857 are a part of the organic
Rankine cycle.
In certain exemplary embodiments, the organic Rankine cycle includes two water-
cooled
condensers 1857 in series. The water-cooled condensers 1857 cool the
intermediate working
fluid stream 1755 to form a condensed working fluid stream 1859. In certain
exemplary
embodiments, the condensed working fluid stream 1859 has a temperature in the
range of
from about 80 to about 150 T. The condensed working fluid stream 1859 is then
directed to
the pump 1760 and is returned to a higher pressure to produce the working
fluid stream 1712
that is directed to the heater 1713.
[0080] FIG. 19 shows an indirect heat recovery system 1900 for utilization
of heat by-
product stream 1901. The heat by-product stream 1901 is the same as that
described above
with regard to heat by-product stream 1701, and for the sake of brevity, the
similarities will
not be repeated hereinbelow. it portion 1901a of the heat by-product stream
1901 can be
utilized to heat a working fluid stream 1912. The portion 1901a of the heat by-
product
stream 1901 thermally contacts the working fluid stream 1912 and transfers
heat to the
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working fluid stream 1912. Suitable examples of the working fluid stream 1912
include, but
are not limited to, water, glycols, therminol fluids, alkanes, alkenes,
chlorofluorocarbons,
hydrofluorocarbons, carbon dioxide (CO2), refrigerants, and mixtures of other
hydrocarbon
components. The portion 1901a of the heat by-product stream 1901 and the
working fluid
stream 1912 enter a heater 1913 to produce a heated working fluid stream 1914
and a reduced
heat exhaust stream 1915. In certain exemplary embodiments, the working fluid
stream 1912
has a temperature in the range of from about 85 to about 160 'F. In certain
exemplary
embodiments, the heated working fluid stream 1914 has a temperature in the
range of from
about 165 to about 455 F. In certain exemplary embodiments, the reduced heat
exhaust
stream 1915 has a temperature in the range of from about 90 to about 500 F.
The reduced
heat exhaust stream 1915 can then be vented to the atmosphere. In certain
exemplary
embodiments, a portion 190 lb of the heat by-product stream 1901 is diverted
through a
bypass valve 1917 and then combined with the reduced heat exhaust stream 1915
to produce
an exhaust stream 1918. In certain exemplary embodiments, the exhaust stream
1918 has a
temperature in the range of from about 90 to about 510 F. In certain
exemplary
embodiments, the heat by-product stream 1901 is entirely directed through the
heater 1913.
[0081] At least a portion 1914a of the heated working fluid stream 1914
enters a
heater 1935 to heat a working fluid stream 1936 to produce a heated working
fluid stream
1937 and a reduced heat working fluid stream 1938. The portion 1914a of the
heated
working fluid stream 1914 thermally contacts the working fluid stream 1936 and
transfers
heat to the working fluid stream 1936. In certain exemplary embodiments, the
working fluid
stream 1936 includes any working fluid suitable for use in an organic Rankine
cycle. In
certain exemplary embodiments, the working fluid stream 1936 has a temperature
in the
range of from about 80 to about 150 'F. In certain exemplary embodiments, the
heated
working fluid stream 1937 has a temperature in the range of from about 160 to
about 450 F.
In certain exemplary embodiments, the heated working fluid stream 1937 is
vaporized. In
certain exemplary embodiments, the heated working fluid stream 1937 is
vaporized within a
supercritical process. In certain exemplary embodiments, the heated working
fluid stream
1937 is superheated. In certain exemplary embodiments, the reduced heat
working fluid
stream 1938 has a temperature in the range of from about 85 to about 155 'F.
In certain
embodiments, a portion 1914b of the working fluid stream 1914 is diverted
through a bypass
valve 1939 and then combined with the reduced heat working fluid stream 1938
to produce
an intermediate working fluid stream 1940. In certain exemplary embodiments,
the
intermediate working fluid stream 1940 has a temperature in the range of from
about 85 to
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about 160 T. The intermediate working fluid stream 1940 is directed to a pump
1942. In
certain exemplary embodiments, the pump 1942 is controlled by a variable
frequency drive
1943. The pump 1942 returns the intermediate working fluid stream 1940 to
produce the
working fluid stream 1912 that enters the heater 1913.
[0082] At least a portion 1937a of the heated working fluid stream 1937 is
then
directed to a turbine-generator system 1950, which is a part of the organic
Rankine cycle.
The portion 1937a of the heated working fluid stream 1937 is expanded in the
turbine-
generator system 1950 to produce an expanded working fluid stream 1951 and
generate
power. In certain exemplary embodiments, the expanded working fluid stream
1951 has a
temperature in the range of from about 80 to about 440 F. In certain
embodiments, the
turbine-generator system 1950 generates electricity or electrical power. In
certain other
embodiments, the turbine-generator system 1950 generates mechanical power. In
certain
embodiments, a portion 1937b of the heated working fluid stream 1937 is
diverted through a
bypass valve 1952 and then combined with the expanded working fluid stream
1951 to
produce an intermediate working fluid stream 1955. In certain exemplary
embodiments, the
intermediate working fluid stream 1955 has a temperature in the range of from
about 80 to
about 445 T.
[0083] The intermediate working fluid stream 1955 is then directed to one
or more
air-cooled condensers 1957. The air-cooled condensers 1957 are a part of the
organic
Rankine cycle. In certain exemplary embodiments, the organic Rankine cycle
includes two
air-cooled condensers 1957 in series. In certain exemplary embodiments, each
of the air-
cooled condensers 1957 is controlled by a variable frequency drive 1958. The
air-cooled
condensers 1957 cool the intermediate working fluid stream 1955 to form a
condensed
working fluid stream 1959. In certain exemplary embodiments, the condensed
working fluid
stream 1959 has a temperature in the range of from about 80 to about 150 F.
The condensed
working fluid stream 1959 is then directed to a pump 1960. The pump 1960 is a
part of the
organic Rankine cycle. In certain exemplary embodiments, the pump 1960 is
controlled by a
variable frequency drive 1961. The pump 1960 returns the condensed working
fluid stream
1959 to a higher pressure to produce the working fluid stream 1936 that is
directed to the
heater 1935.
[0084] FIG. 20 shows an indirect heat recovery system 2000 according to
another
exemplary embodiment. The heat recovery system 2000 is the same as that
described above
with regard to heat recovery system 1900, except as specifically stated below.
For the sake of
brevity, the similarities will not be repeated hereinbelow. Referring now to
FIG. 20, the
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intermediate working fluid stream 1955 is directed to one or more water-cooled
condensers
2057. The water-cooled condensers 2057 are a part of the organic Rankine
cycle. In certain
exemplary embodiments, the organic Rankine cycle includes two water-cooled
condensers
2057 in series. The water-cooled condensers 2057 cool the intermediate working
fluid stream
1955 to form a condensed working fluid stream 2059. In certain exemplary
embodiments,
the condensed working fluid stream 2059 has a temperature in the range of from
about 80 to
about 150 F. The condensed working fluid stream 2059 is then directed to the
pump 1960
and is returned to a higher pressure to produce the working fluid stream 1936
that is directed
to the heater 1935.
[0085] The present invention may employ any number of working fluids in
the
organic Rankine cycle. Suitable examples of worldng fluids for use in the
organic Rankine
cycle include, but are not limited to, ammonia (NII3), bromine (Br2), carbon
tetrachloride
(CC14), ethyl alcohol or ethanol (CH3CH2OH, C2H60), furan (C4H40),
hexafluombenzene
or perfluoro-benzene (C6F6), hydrazine (N2H4), methyl alcohol or methanol
(CH3OH),
monochlorobenzene or chlorobenzene or chlorobenzol or benzine chloride
(C6H5C1), n-
pentane or normal pentane (nC5), i-hexane or isohexane (iC5), pyridene or
azabenzene
(C5H5N), refrigerant 11 or freon 11 or CFC-11 or R-11 or
trichlorofluoromethane (CC131;),
refrigerant 12 or freon 12 or R-12 or dichlorodifluoromethane (CC12F2),
refrigerant 21 or
freon 21 or CFC-21 or R-21 (CIIC12F), refrigerant 30 or freon 30 or CFC-30 or
R-30 or
dichloromethane or methylene chloride or methylene dichloride (CH2C12),
refrigerant 115 or
freon 115 or CFC-115 or R-115 or chloro-pentafluoroethane or
monochloropentafluoroethane, refrigerant 123 or freon 123 or HCFC-123 or R-123
or 2,2
dichloro-1,1,1-trifluoroethane, refrigerant 123a or freon 123a or HCFC-123a or
R-123a or
1,2-dichloro-1,1,2-trifluoroethane, refrigerant 123b1 or freon 123b1 or HCFC-
123b1 or R-
123b1 or halothane or 2-bromo-2-chloro-1,1,1-trifluoroetharie, refrigerant
134A or freon
134A or HFC-134A or R-134A or 1,1,1,2-tetrafluoroethane, refrigerant 150A or
freon 150A
or CFC-150A or R-150A or dichloroethane or ethylene dichloride (CH3CHC12),
thiophene
(C4H4S), toluene or methylbenzene or phenylmethane or toluol (C7H8), water
(H20),
carbon dioxide (CO2), and the like. In certain exemplary embodiments, the
working fluid
may include a combination of components. For example, one or more of the
compounds
identified above may be combined or with a hydrocarbon fluid, for example,
isobutene.
However, those skilled in the art will recognize that the present invention is
not limited to any
particular type of working fluid or refrigerant. Thus, the present invention
should not be
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considered as limited to any particular working fluid unless such limitations
are clearly set
forth in the appended claims.
[0086] The present application is generally directed to various heat
recoveiy systems
and methods for producing electrical and/or mechanical power from a heat
source. The
exemplary systems may include a heat exchanger, a turbine-generator set, a
condenser heat
exchanger, and a pump. The present invention is advantageous over conventional
heat
recovery systems and methods as it utilizes heat that would otherwise be
rejected to the
atmosphere to produce electricity and/or mechanical power, thus increasing
process
efficiency
[0087] Therefore, the present invention is well adapted to attain the ends
and
advantages mentioned as well as those that are inherent therein. The
particular embodiments
disclosed above are illustrative only, as the present invention may be
modified and practiced
in different but equivalent manners apparent to those skilled in the art
having the benefit of
the teachings herein. While numerous changes may be made by those skilled in
the art, such
changes are encompassed within the spirit of this invention as defined by the
appended
claims. Furthermore, no limitations are intended to the details of
constniction or design
herein shown, other than as described in the claims below. It is therefore
evident that the
particular illustrative embodiments disclosed above may be altered or modified
and all such
variations are considered within the scope and spirit of the present
invention. The terms in the
claims have their plain, ordinary meaning unless otherwise explicitly and
clearly defined by
the patentee.
31
