Power plants – Motive fluid energized by externally applied heat – Process of power production or system operation
Reexamination Certificate
2000-03-14
2001-03-06
Nguyen, Hoang (Department: 3748)
Power plants
Motive fluid energized by externally applied heat
Process of power production or system operation
C060S649000, C060S651000, C060S671000
Reexamination Certificate
active
06195997
ABSTRACT:
TECHNICAL FIELD
This invention pertains to the field of energy conversion and specifically to the conversion of heat energy to mechanical energy.
BACKGROUND OF THE INVENTION
Energy conversion engines have long been employed to recover process heat and convert it to mechanical energy as in the familiar Rankine cycle. Typical systems are in a series of patents by Alexander Kalina and various coworkers such as U.S. Pat. Nos. 5,095,708; 5,029,444; 4,982,568; 4,899,545; 4,732,005; 4,604,867; 4,586,340; 4,548,043; and 4,489,563. Scharpf, U.S. Pat. No. 5,842,345 teaches the use of two component working fluids, preferring ammonia and water, in a heat recovery method. DeVault U.S. Pat. No. 5,555,738, teaches use of an ammonia water refrigeration system to cool the inlet air of a gas turbine for improved efficiency.
The art has not heretofore recognized the unexpected advantage of using a two component working fluid which is separated into it's a more volatile and a less volatile component and the more volatile component used in a refrigerant loop to provide refrigeration capacity then recombined with the less volatile component to provide a multi-component working fluid for heat recovery.
SUMMARY OF THE INVENTION
The invention may be described in several ways as alternate embodiments of the same novel discovery. In one embodiment, the invention provides a method of recovering energy that comprises:
a. providing a selected working fluid comprising at least two components to a first pump;
b. feeding the selected working fluid to a dividing means;
c. dividing the working fluid into a first stream and a second stream,
d. feeding the first stream at an intermediate pressure to a first heat transfer zone to transfer heat to the working fluid stream thereby heating the stream to a higher temperature,
e. feeding the higher temperature stream to a separation means,
f. separating a volatile component enriched stream and a volatile component depleted stream;
g. cooling the volatile component enriched stream;
h. further cooling the volatile component enriched stream in a heat exchanger;
i. feeding the volatile component enriched stream to an expansion means;
j. expanding the volatile component enriched stream to a lower temperature and pressure;
k. feeding the expanded lower temperature and pressure volatile component enriched stream to a heat exchanger where the volatile enriched stream is partially or completely vaporized by heat exchange while absorbing heat from an external stream;
l. feeding the at least partially vaporized volatile component enriched stream to a heat exchanger;
m. feeding the volatile component enriched stream to the mixing means;
n. feeding the volatile component depleted stream to the mixing means;
o. feeding the second working fluid stream to a second pump and increasing the pressure of the second working fluid stream to a high pressure;
p. feeding the high pressure second working fluid stream to a second heat exchange zone wherein heat is transferred to the high pressure second working fluid stream to produce a higher temperature and pressure condition of the second working fluid stream;
q. work expanding the higher temperature and pressure second working fluid stream to convert a portion of the heat energy to mechanical energy;
r. returning the second working fluid stream to the mixer; and
s. repeating the cycle as set out above.
In a preferred embodiment the method further comprises:
a. feeding the second working fluid through one or more heat exchangers to recover heat while cooling this stream;
b. feeding the work expanded second stream to the mixing means;
c. mixing the streams to provide a combined working fluid stream;
d. cooling and condensing the combined working fluid stream by heat exchanging with a bulk heat sink such as ambient air or water; and
e. returning the combined working fluid stream to the feed-line of the low pressure pumping stage to provide the selected working fluid.
In another preferred embodiment the method further comprising providing multiple expansion means in series relationship and expanding the volatile component to provide a series of partially condensed working fluid intermediate fractions and passing such intermediate fractions to a reboiler.
Preferably, the selected working fluid is selected from the group consisting of ammonia and water; sulfur dioxide and water; mixed hydrocarbons; ammonia and brine; or sulfur dioxide and brine. More preferably, the selected working fluid comprises ammonia and water or ammonia, water and salts. Most preferably, the selected working fluid consists essentially of ammonia and water. In an especially preferred embodiment, the volatile component enriched stream is substantially a pure component.
In an optional embodiment the method further comprises the steps of feeding the expanded volatile component enriched stream to a second mixing means and feeding a third component into the second mixing means to provide a mixed components stream and feeding the mixed components stream to a refrigerant condenser, separating the mixed components and recycling the separated components.
The stream may also be fed back through multiple heat exchangers to further increase heat uptake and process efficiency and/or to produce a lower refrigerant temperature.
Alternate pumping arrangements can be utilized to provide the intermediate pressure stream that generates the volatile component enriched stream and the second working fluid stream
Alternately the volatile enriched stream can be heat exchanged to partially or completely vaporize this stream while providing refrigeration to a separate fluid-circulating stream.
In an alternate embodiment, the invention is an energy recovery apparatus that comprises:
a. fluid conduit means connecting all components listed below;
b. a vessel for receiving a working fluid;
c. a dividing means positioned between said vessel and a low pressure pumping means;
d. a low pressure pumping means connected to receive a divided portion of a working fluid and connected on the pressure side to a first heat transfer means;
e. a separation means operably connected to the first heat transfer means and configured to separate a more volatile component of the working fluid from a less volatile component of the working fluid, having a discharge point for discharging a separated more volatile component and a discharge point for the less volatile component;
f. a heat transfer means positioned to receive the more volatile component from the separation means;
g. an expansion means connected to the heat transfer means and configured to receive a cooled more volatile component from the heat transfer means and expand said component to a lower pressure zone, thereby lowering the temperature of the more volatile component;
h. a mixing means operably connected to the separation means and configured to receive the less volatile component from the separation means and the more volatile component from the expansion means;
i. a high pressure pump means connected on its suction side to the dividing means and configured to receive a portion of the selected working fluid and connected on its high pressure side to a second heat transfer means;
j. work expansion means connected to the second heat transfer means on its high pressure side and to the mixing means on its low pressure side;
k. a heat sink means configured to provide a fully liquefied working fluid for feeding to the dividing means;
l. a working fluid comprising at least one more volatile component and a less volatile component in a ratio such that the at least one more volatile component is vaporized by heat available from the energy to be recovered in sufficient quantity to provide the desired product temperature when expanded in the expansion means while the combined working fluid can be fully condensed by the available heat sink means at pressures acceptable in the heat sink means.
In a preferred embodiment the invention further provides:
a. a second mixer connected by fluid conduit means to the expansion means to receive the expanded more volatile compon
Lewis Larry
Monroe Walter D.
Pinion James H.
Lewis Monroe Power Inc.
McGregor Martin L.
Nguyen Hoang
LandOfFree
Energy conversion system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Energy conversion system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Energy conversion system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2455370