U.S. patent application number 12/563659 was filed with the patent office on 2010-04-08 for water production system and method with air bypass.
This patent application is currently assigned to ISLAND SKY CORPORATION. Invention is credited to Thomas MERRITT.
Application Number | 20100083673 12/563659 |
Document ID | / |
Family ID | 42073815 |
Filed Date | 2010-04-08 |
United States Patent
Application |
20100083673 |
Kind Code |
A1 |
MERRITT; Thomas |
April 8, 2010 |
WATER PRODUCTION SYSTEM AND METHOD WITH AIR BYPASS
Abstract
An apparatus and method for condensing water vapor in air to
extract liquid water includes an air duct, an air movement device,
and a refrigeration system. The air duct has an entry port, an
intermediate port, and an exit port; while the refrigeration system
includes at least one evaporator and condenser within the air duct.
The air movement device may be a fan within the air duct, to cause
air flow through the condenser and out the exit port. The air has a
dew point, and the evaporator temperature is at that dew point or
less, to cause liquid water to condense on the evaporator's
exterior surface. The intermediate port of the air duct is between
the evaporator and condenser, such that air can enter the air duct
by at least two paths: through the entry port and evaporator, and
through the intermediate port which bypasses the evaporator.
Inventors: |
MERRITT; Thomas; (Hollywood,
FL) |
Correspondence
Address: |
CHRISTOPHER & WEISBERG, P.A.
200 EAST LAS OLAS BOULEVARD, SUITE 2040
FORT LAUDERDALE
FL
33301
US
|
Assignee: |
ISLAND SKY CORPORATION
Hollywood
FL
|
Family ID: |
42073815 |
Appl. No.: |
12/563659 |
Filed: |
September 21, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61102120 |
Oct 2, 2008 |
|
|
|
61184956 |
Jun 8, 2009 |
|
|
|
Current U.S.
Class: |
62/93 ;
62/285 |
Current CPC
Class: |
Y02A 20/00 20180101;
Y10T 137/7737 20150401; Y02A 20/109 20180101; E03B 3/28
20130101 |
Class at
Publication: |
62/93 ;
62/285 |
International
Class: |
F25D 21/14 20060101
F25D021/14; F25J 1/02 20060101 F25J001/02 |
Claims
1. An apparatus for extracting water from air, comprising: an air
duct having an entry port, an intermediate port, and an exit port;
a refrigeration system, including an evaporator and a condenser
within the air duct, the evaporator having a temperature of at most
a dew point of air contacting the evaporator, to cause liquid water
to condense on an exterior surface of the evaporator; the air duct
defining: a first air flow path sequentially through the entry
port, evaporator, condenser, and exit port; and a second air flow
path sequentially through the intermediate port, condenser, and
exit port; and an air movement device disposed within the air duct,
operable to draw air through the air duct along the first and
second air flow paths.
2. The apparatus according to claim 1, further comprising a bypass
valve affixed to the intermediate port, selectively operable
between an open position and a closed position.
3. The apparatus according to claim 2, wherein the bypass valve is
selectively operable to a plurality of positions between the open
position and the closed position.
4. The apparatus according to claim 2, further comprising a
controller adapted to operate the bypass valve according to a
temperature and a humidity of the air.
5. The apparatus according to claim 4, wherein the controller is
operative to open the bypass valve when the air exceeds a selected
temperature, and to at least partially close the bypass valve when
the air falls below the selected temperature.
6. The apparatus according to claim 1, further comprising three
additional evaporators and three additional condensers, such that
four sets of an evaporator and condenser are orthogonally arranged
to define a rectangular air passage through the air movement
device.
7. The apparatus according to claim 6, wherein the exit port is
positioned at one end of the rectangular passage.
8. The apparatus according to claim 1, further comprising a
compressor, a first and second expansion valve, an additional
evaporator, and an additional condenser, wherein a refrigerant in
the refrigeration system passes sequentially from the compressor to
the condenser, the additional condenser, the expansion valves, the
evaporators, and then returns to the compressor.
9. The apparatus according to claim 8, wherein the evaporator and
additional evaporator are connected to the refrigeration system in
parallel, and the condenser and additional condenser are connected
to the refrigeration system in series.
10. The apparatus according to claim 8, wherein a refrigerant in
the refrigeration system exits the condenser in a gaseous state and
exits the additional condenser in a liquid state such that the
condenser acts as a de-superheater.
11. The apparatus according to claim 8, further comprising a second
refrigeration system, the second refrigeration system including a
second compressor, a third expansion valve, and a fourth expansion
valve, wherein the first and second refrigeration systems define
separate closed-loop refrigerant paths.
12. The apparatus according to claim 2, wherein the air duct
further comprises an additional intermediate port, the intermediate
port providing a conditional air bypass, the additional
intermediate port providing a persistent air bypass.
13. The apparatus according to claim 1, wherein the condenser has a
greater capacity for air flow than the evaporator.
14. The apparatus according to claim 1, further comprising: an ice
sensor, the ice sensor sensing ice buildup on the evaporator; and a
switch coupled to the ice sensor to shut off the refrigeration
system when ice is present.
15. The apparatus according to claim 1, further comprising a water
collection vessel positioned proximate to the evaporator for
collecting water.
16. The apparatus according to claim 1, wherein the air movement
device is a fan.
17. An apparatus for extracting water from air, comprising: an air
duct having an entry port, an intermediate port, and an exit port;
a refrigeration system, the refrigeration system including an
evaporator and a condenser within the air duct, the evaporator
having a temperature of at most a dew point of air contacting the
evaporator to cause liquid water to condense on an exterior surface
of the evaporator; an air movement device disposed within the air
duct, operable to cause air to flow through the condenser and out
the exit port; and the intermediate port being positioned between
the evaporator and condenser, such that air can enter the air duct:
(i) through the entry port and evaporator, and (ii) through the
intermediate port, bypassing the evaporator.
18. A method of using a water production system to extract water
from air, the water production system including a refrigeration
system having a cooling element, and an air duct having an entry
port, an intermediate port, and an exit port, the method
comprising: operating the air movement device to cause air to flow
along: a first flow path into the entry port, through the cooling
element, and out the exit port; and a second flow path into the
intermediate port, and out the exit port, thus bypassing the
cooling element; operating the refrigeration system to cause the
cooling element to maintain a temperature of at most a dew point of
air contacting the cooling element; condensing liquid water on an
exterior surface of the cooling element; and collecting the liquid
water.
19. The method according to claim 18, wherein the water production
system also includes a bypass valve located proximate the
intermediate port, wherein operating the air movement device
further comprises: determining a temperature of air; opening the
bypass valve when the temperature exceeds a selected temperature to
allow air to flow into the intermediate port; and at least
partially closing the bypass valve to resist flow of air into the
intermediate port when the temperature falls below the selected
temperature.
20. The method according to claim 18, wherein the water production
system also includes an additional intermediate port and bypass
valve located proximate the intermediate port, wherein operating
the air movement device further comprises: selectively opening and
closing the bypass valve to allow and resist air flow into the
intermediate port, respectively, and maintaining the additional
intermediate port in an open position.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to U.S. Provisional
Application Ser. No. 61/102,120, entitled "Methods and Systems for
Potable Water Production," filed Oct. 2, 2008, and to U.S.
Provisional Application Ser. No. 61/184,956, entitled "Method And
System For Water Recovery From Air Using Combined Receiver And
Water Cooled Condenser," filed Jun. 8, 2009, the entirety of both
of which are incorporated herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
FIELD OF THE INVENTION
[0003] The present invention relates generally to production of
water, and more specifically to improved systems and methods for
extracting water from water vapor, for example from the
atmosphere.
BACKGROUND OF THE INVENTION
[0004] Ambient air naturally contains some quantity of water vapor,
so the general atmosphere is a potential water source. Extracting
this water from the surrounding atmosphere presents several
challenges. Other attempts to produce water from atmospheric air
have typically fallen short of the desirable criteria, including
efficiency in the amount of water produced per the amount of energy
used, extracting the greatest possible percent of the moisture
available in the air under local conditions, and producing
acceptable quantities of water at all times of day and in various
weather, seasons, and climates. Therefore, atmospheric water vapor
is an essentially untapped source of greatly needed water supplies
that is potentially available worldwide.
[0005] Refrigeration systems have been known for some time.
Vapor-compression cycle refrigeration systems are most common
today, but other types of refrigeration are possible including gas
absorption and heat pumps. If the refrigeration system uses a vapor
compression cycle, it may include a compressor, evaporator,
expansion valve, and condenser. Diagrams of an example vapor
compression refrigeration system, and its thermodynamic operation,
are shown in FIGS. 11-13.
[0006] Most refrigeration systems have some cooling element,
through which air passes to shed heat and reach a lower
temperature. In a vapor compression cycle refrigeration system, the
cooling surface of the cooling element will be an exterior surface
of the evaporator. An evaporator having a temperature of at most a
dew point of air contacting the evaporator will cause liquid water
to condense on an exterior surface of the evaporator.
[0007] Whenever this cooling element has a temperature at or less
than the local dew point of the air, water vapor in the air will
tend to condense into droplets of liquid water. When a cooling
element has a temperature at or less than the freezing point of
water, such as in a freezer, water vapor in the air will tend to
condense and then freeze into ice.
[0008] In most residential and commercial refrigeration systems,
this condensation is considered undesirable, and some refrigeration
systems even have features for ameliorating them. However, the
principles causing such condensation can be used to produce liquid
water from water vapor in atmospheric air.
[0009] Exemplary methods of water production and accompanying
apparatus are described in U.S. Pat. No. 6,343,479, entitled
"Potable Water Collection Apparatus" which issued on Feb. 5, 2002,
and U.S. Pat. No. 7,121,101, entitled "Multipurpose Adiabatic
Potable Water Production Apparatus And Method" which issued on Oct.
17, 2006, the entire contents of both of which are incorporated by
reference.
[0010] These patented methods and devices present viable means of
extracting liquid water from atmospheric air, including apparatus
for transforming atmospheric water vapor into potable water, and
particularly for obtaining drinking quality water through the
formation of condensed water vapor on surfaces maintained at a
temperature at or below the dew point for a given ambient
condition. The surfaces upon which the water vapor is condensed are
kept below the dew point by a refrigerant medium circulating
through a closed fluid path, which includes refrigerant evaporation
apparatus, thereby providing cooling of air flowing through the
device, and refrigerant condensing apparatus to complete the
refrigeration cycle.
[0011] It is desirable to be able to control the amount of and
temperature of the air passing over the evaporator to provide
efficient and economical water production during conditions when
the ambient wet bulb and dry bulb temperatures indicate high
relative humidity or less than ideal atmospheric conditions.
SUMMARY OF THE INVENTION
[0012] The present invention advantageously provides a system,
device and method for extracting water from air. A water production
system may include an air duct, an air movement device, and a
refrigeration system. The air duct may have an entry port, an
intermediate port, and an exit port. The air movement device may be
a fan inside the air duct. The refrigeration system may include a
cooling element such as for example an evaporator as well as a
condenser within the air duct, with the evaporator maintaining a
temperature at the dew point or less, to cause liquid water to
condense on the evaporator.
[0013] The air duct defines a first air flow path sequentially
through the entry port, evaporator, condenser, and exit port. And
the air duct also defines a second air flow path sequentially
through the intermediate port, condenser, and exit port. This
second air flow path bypasses the evaporator.
[0014] In some embodiments of the present invention, the
intermediate port may remain open, or may be fitted with a bypass
valve to control the bypass air flow. If a bypass valve is
provided, it may be binary (open or closed) or fully adjustable to
a variety of positions between and including open or closed. A
bypass valve may be manually operated or have an automatic
controller, which may operate the bypass valve according to certain
conditions including the air temperature and humidity. A controller
may for example be programmed to open the bypass valve when the air
exceeds a selected temperature, and to close the bypass valve when
the air falls below that temperature.
[0015] In other embodiments of the present invention, the air duct
may also have at least one additional intermediate port, such that
the intermediate port may provide a conditional air bypass, and the
additional intermediate port may provide a persistent air
bypass.
[0016] The elements of a water production system according to the
present invention may be selected from among many different
suitable materials having the desired physical properties. Some of
these characteristics may include for example strength, thermal
insulation or transmission, corrosion resistance, and material
performance in a broad range of temperatures and pressures.
Acceptable materials may include metals such as for example copper,
aluminum, steel, stainless steel, as well as polymers.
[0017] Of course, a water collection vessel may be positioned
proximate, e.g., under, the evaporator to collect liquid water.
[0018] In accordance with another aspect the present invention
provides a method of using a water production system to extract
water from air. The water production system includes a
refrigeration system having a cooling element and an air duct
having an entry port, an intermediate port, and an exit port in
which the air movement device is operated to cause air to flow
along a first flow path into the entry port, through the cooling
element, and out the exit port, and along a second flow path into
the intermediate port, and out the exit port, thus bypassing the
cooling element. The refrigeration system is operated to cause the
cooling element to maintain a temperature of at most a dew point of
air contacting the cooling element. Liquid water is condensed on an
exterior surface of the cooling element and the liquid water is
collected.
[0019] A more complete understanding of the present invention, and
its associated advantages and features, will be more readily
understood by reference to the following description and claims,
when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] A more complete understanding of the present invention, and
the attendant advantages and features thereof, will be more readily
understood by reference to the following detailed description when
considered in conjunction with the accompanying drawings
wherein:
[0021] FIG. 1 is a partial perspective view of an exemplary water
production system with air bypass constructed in accordance with
the principles of the present invention;
[0022] FIG. 2 is an exterior perspective view of a water production
system constructed in accordance with the principles of the present
invention;
[0023] FIG. 3 is a top view of a water production system
constructed in accordance with the principles of the present
invention;
[0024] FIG. 4 is a diagrammatic top view of the exemplary water
production system of FIGS. 1-3;
[0025] FIG. 5 is a diagrammatic side view of the exemplary water
production system of FIGS. 1-3;
[0026] FIG. 6 is a partial exploded view of refrigeration system
components of an exemplary water production system, constructed in
accordance with the principles of the present invention;
[0027] FIG. 7 is a partial exploded view of refrigeration and
structural components of an exemplary water production system,
constructed in accordance with the principles of the present
invention;
[0028] FIG. 8 is a partial perspective view of an exemplary water
production system with air bypass constructed in accordance with
the principles of the present invention;
[0029] FIG. 9 is a partial perspective view of an exemplary water
production system with air bypass constructed in accordance with
the principles of the present invention;
[0030] FIG. 10 is a partial perspective view of the water
production system of FIG. 9;
[0031] FIG. 11 is a psychrometric chart of water, showing the
physical properties of moist air at sea level;
[0032] FIG. 12 is a representative diagram of temperature and
entropy for an exemplary refrigerant; and
[0033] FIG. 13 is a representative diagram of a known refrigeration
system.
DETAILED DESCRIPTION OF THE INVENTION
[0034] The present invention advantageously provides an improved
system and method for extracting water from water vapor, for
example from the atmosphere. The water production system of the
present invention may have various sizes, arrangements and
features.
[0035] Some aspects of the present invention relate to combinations
of components and method steps for implementing systems and methods
to improve the efficiency and operation of water production
systems. Accordingly, some components have been represented where
appropriate by conventional symbols in the drawings, showing only
those specific details that are pertinent to understanding the
embodiments of the present invention, so as to avoid details that
will be readily apparent to those of ordinary skill in the art
having the benefit of this description.
[0036] Relational terms, such as "first" and "second," "top" and
"bottom," and the like, may be used solely to distinguish one
entity or element from another entity or element, without
necessarily requiring or implying any physical or logical
relationship or order between such entities or elements.
[0037] Referring to the drawings, various embodiments of water
production devices are illustrated. The illustrations of course
depict only some of many different possible designs that are within
the scope of the present invention. In particular, the present
invention encompasses water production systems having numerous
combinations of elements, and the description of any element also
contemplates providing more than one of that element. For clarity
and convenience, the present detailed description will only
describe a few specific embodiments of the present invention.
[0038] An apparatus for extracting water from the water vapor in
atmospheric air may generally include an air duct, a refrigeration
system, and an air movement device. The air duct may have one or
more ports, including an entry port and an exit port. The air
movement device may be a fan disposed within the air duct, operable
to draw air through the air duct.
[0039] In some embodiments of the present invention, an
intermediate port may be provided between the entry port and exit
port, such that the air duct defines a first and second air flow
path. The first air flow path may proceed sequentially through the
entry port, evaporator, condenser, and exit port. In contrast, the
second air flow path may proceed sequentially through the
intermediate port, condenser, and exit port, thus bypassing the
evaporator. In other words, with the intermediate port being
positioned between the evaporator and condenser, air can enter the
air duct: (i) through the entry port and evaporator, and (ii)
through the intermediate port, bypassing the evaporator. The air
movement device in such embodiments is capable of moving air
through the air duct along the first and second air flow paths.
[0040] The refrigeration system may be of various types, including
vapor compression cycles, gas absorption and heat pumps. Regardless
of which type of refrigeration system is chosen, the refrigeration
system should have at least one cooling element, with an exterior
cooling surface. During operation, the cooling surface is
maintained at a temperature which is at or less than a dew point of
air. In other words, atmospheric air flowing through a water
production system can contact a cooling element of a refrigeration
system having a temperature of at most the dew point, to cause
liquid water to condense on a cooling surface.
[0041] With specific reference to the drawings, in which like
reference designators refer to like elements, an exemplary
embodiment of a water production system according to the present
invention is shown in FIG. 1, and is generally designated as "10."
Water production system 10 has a substantially rectangular air duct
or passage 12, a refrigeration system 14a-b, and an air movement
device in the form of a fan 16.
[0042] As is shown in FIGS. 1 and 2, the air duct 12 may have
various configurations of entry ports, intermediate ports, and exit
ports. In the embodiment depicted in the drawings, air duct 12 has
four entry ports 18a-d (referred to collectively herein as "entry
port 18"), at least four intermediate ports 20a-d (referred to
collectively herein as "intermediate port 20"), and a large exit
port 22. The exit port 22 is positioned at one end of the air duct
12, and the fan 16 is positioned near the exit port 22.
[0043] The refrigeration systems 14a and 14b (referred to
collectively herein as "refrigeration system 14") of the present
invention may also have various arrangements of refrigeration
components, including for example compressors 24a and 24b (referred
to collectively herein as "compressor 24"), evaporators 28a-d
(referred to collectively herein as "evaporators 28"), expansion
valves 26a-d (referred to collectively herein as "expansion valves
26"), and condensers 30a-d (referred to collectively herein as
"condensers 30"). An evaporator 28 and a condenser 30 may both be
positioned within an air duct 12 of the present invention. The
refrigeration system may provide one or more closed circuits for a
refrigerant medium. For example, a refrigeration circuit may be
arranged from a compressor, to a condenser, to an expansion valve,
to an evaporator, and back to the compressor.
[0044] The particular embodiment of a water production system shown
in FIGS. 1 and 2 provides two separate refrigeration systems 14a
and 14b, including two compressors 24 and four expansion valves 26,
and four matching sets of evaporators 28 and condensers 30. The
sets of evaporators 28 and condensers 30 are orthogonally arranged
to define a rectangular air duct 12 through the fan 16.
[0045] Water production systems according to the present invention
may have one or more bypass ports that remain open, or may be
selectively opened and closed, either in a binary or selectively
adjustable fashion. For example, water production system 10 may be
provided with intermediate ports 20 defined on the top of the water
production system between each pair of evaporators 28 and
condensers 30, and additional intermediate ports 32a and 32b
(referred to collectively herein as "intermediate ports 32")
defined on both sides of each pair of evaporators 28 and condensers
30.
[0046] Accordingly, in the present embodiment there are: (i) four
sets of first flow paths, each of which begins with an entry port
18, proceeds through an evaporator 28, then a condenser 30, and out
the exit port 22; and (ii) four sets of second flow paths, each of
which begins with intermediate ports 20 and 32, proceeds through a
condenser 30, and out the exit port 22, thus bypassing the
evaporators.
[0047] The operating temperature of the evaporator depends upon the
pressure of the refrigerant flowing through it. This refrigerant
pressure is affected, in turn, by the volume of air flowing through
the evaporator. By passing a portion of air flowing through the air
duct directly to the condenser without passing through the
evaporator, refrigerant pressure in the evaporator is lowered, and
the operating temperature of the evaporator is lowered, thereby
improving the efficiency of the system to produce water.
[0048] Differing types of intermediate ports are possible. For
example, intermediate ports may have a variety of shapes, including
square, rectangular, polygonal, rounded, circular, and even
irregular shapes. Likewise, intermediate ports may have any
suitable arrangement, positioning, number, or layout. A singular
intermediate port may suffice, or a series of smaller intermediate
ports may be used.
[0049] Bypass ports may also be controllable, with bypass valves
that may be opened or closed, or may be selectively adjusted to
numerous discrete partially-open positions, or may be manipulated
continuously to any arbitrary position inclusively between an open
or closed position. If more than one intermediate port is provided
or more than one bypass valve is provided, then they may all be
collectively adjusted or movable as a group, or individually, or in
any desired combination or arrangement.
[0050] Again, differing types and shapes of bypass valves are
possible. For example, bypass valves may be planar, louvered, an
iris diaphragm, or any other suitable shape. Bypass valves may also
move in different ways, including for example rotating, sliding,
hinged turning, expansion and contraction. Moreover, the elements
of a bypass valve 34 may have various physical characteristics,
including flexible, inflexible, and resilient.
[0051] In particular, a bypass valve 34a-d (referred to
collectively herein as "bypass valves 32") may be affixed to
intermediate ports 20, selectively operable between open and closed
positions. Bypass valves 34 may also be selectively operable to a
plurality of partially open positions between the open and closed
positions. Bypass valves may be manually operable or automatic,
programmed to change positions in response to any suitable
condition(s), including at selected times, temperatures, humidity,
geographic location, the presence or absence of sunlight or other
weather conditions, etc. In addition, although the drawing figures
show four bypass valves 34, fewer or greater than four can be
implemented as needed. It is also contemplated that the bypass
valves 34 can be operated, i.e., opened/closed, together or each
individual bypass valve 34 can be separately controlled.
[0052] As is shown in FIG. 3, one or more controllers 36 may be
provided to operate the bypass valves according one or more
selected criteria, which may for example include air temperature,
humidity, time of day, or even the amount of water in a collection
container. In other words, the controller 36 may be operative to
open the bypass valve 34 when the air exceeds a selected
temperature, and to close or partially close the bypass valve when
the air falls below the selected temperature. This transition
temperature may be selected by determining the temperature at
which, with the bypass valves closed, the evaporator reaches its
maximum air flow capacity.
[0053] The controller 36 may have any configuration suitable for
controlling one or more bypass valves as desired, including for
example electromechanical timers and apparatus for manipulating
valve components, or computer or CPU-based systems that are
programmable to adjust bypass valve(s) according to a variety of
inputs and conditions. Different sensors or input devices may be
used to guide the controller, including for example a clock, timer,
thermometer, humidity sensor, rain sensor, light sensor, etc.
[0054] In differing conditions, whether for example atmospheric,
climate, time, humidity, or daylight, a different component or
subsystem of a refrigeration system may reach its capacity. For
example, at high temperatures and high humidity, operation of the
refrigeration system may be limited by the capacity of an
evaporator, so it may be desirable to allow some or more air flow
to bypass that evaporator. Conversely for example, at lower
temperatures, operation of the refrigeration system will tend not
to exceed the capacity of an evaporator, so it may be desirable to
lessen the bypass air flow.
[0055] Accordingly, the bypass valves may be closed at lower
temperatures, thereby allowing more air to flow over the
evaporator. At higher temperatures, the bypass valves may be
opened, thereby allowing more air over the condenser in comparison
to the amount of air flowing over the evaporator. Less air over the
evaporator will tend to lower the refrigerant temperature in the
evaporator.
[0056] In one embodiment, the bypass valve position may be
controlled by a stepper motor. A specific example water production
system may operate with the bypass valves closed, for example at
approximately 10 pounds of air per minute. With the bypass valves
open, the air pressure capacity may drop to about 8 pounds per
minute, thereby requiring less energy to operate. With larger
bypass ports, the air pressure capacity may be able to be lowered
to approximately 5 pounds per minute.
[0057] The additional intermediate ports 32 may remain open and
provide a persistent air bypass, in that air flowing into
additional intermediate ports 32 bypasses the evaporators 28. In
contrast, adjustable intermediate ports 20 may provide a
conditional air bypass. Depending on the condition of the bypass
valves 34, whether they are open, partially open, or closed, air
may flow into intermediate ports 20 and bypass the evaporators 28
to a greater or lesser extent.
[0058] While conventional refrigeration systems may be optimized
for cooling the air in a chamber, water production systems are
optimized for production of water. Accordingly, bypass ports may be
desirable because otherwise a water production system such as
system 10 will tend to exceed the air flow capacity of the
evaporators. If desired for improved efficiency and operation, the
water production system may be optimized by selecting condensers
with a greater capacity for air flow than the evaporators.
[0059] In embodiments having more than one evaporator and
condenser, it may also be desirable to connect the evaporators to
the refrigeration system in parallel, and yet connect the
condensers to the refrigeration system in series. In this case, the
refrigeration system may be arranged to cause the refrigerant to
exit the first condenser in a gaseous state, and to exit the second
condenser in a liquid state, such that the first condenser acts as
a de-superheater.
[0060] Water production systems of the present invention may also
be provided with an ice sensor 38 capable of sensing ice buildup on
an evaporator 28, and a switch 40 coupled with the ice sensor 38 to
shut off the refrigeration system 14 when ice is present, with the
air movement device 16 remaining in operation.
[0061] With specific reference to FIGS. 4 and 5, each refrigeration
circuit may include a compressor 24, a first and second evaporator
28, a first and second expansion valve 26, and a first and second
condenser 30. The refrigerant passes sequentially from the
compressor 24 to the first condenser 30, then to the second
condenser 30, then to the expansion valve 26, then simultaneously
to both of the first and second evaporators 28, and then returns to
the compressor 24.
[0062] Another embodiment of the present invention may provide one
or more additional refrigeration systems. For example, the
illustrated embodiment includes an additional compressor and
expansion valve. The first and second refrigeration systems define
separate closed-loop refrigerant paths, and each refrigeration
system is arranged in a similar fashion.
[0063] Of course, one or more water collection vessels or
containers 42 may be positioned near the evaporators 28 for
collecting the liquid water. If desired, these containers 42 may be
further coupled to additional water treatment apparatus, or
filtration systems, etc.
[0064] In operation of the water production systems of the present
invention, a method of extracting water from air may include, for
example, providing an air duct having an entry port, an
intermediate port, and an exit port; providing an air movement
device; and providing a refrigeration system including a cooling
element. The method may also include operating the air movement
device to cause air to flow along a first and second air flow path.
The first flow path may be into the entry port, through the cooling
element, and out the exit port, while the second flow path may be
into the intermediate port, and out the exit port, thus bypassing
the cooling element. The method according to the present invention
may further include operating the refrigeration system to cause the
cooling element to maintain a temperature of at most a dew point of
air contacting the cooling element. The present invention may also
include condensing liquid water on an exterior surface of the
cooling element, and collecting the liquid water.
[0065] In the method of the present invention, a bypass valve may
further be provided, and may also include determining a temperature
of the air, opening the bypass valve when the temperature exceeds a
selected temperature, and closing the bypass valve when the
temperature falls below the selected temperature. The method of the
present invention may also include adjusting one or more bypass
valves in response to a variety of conditions, inputs or sensors,
including for example a thermometer, clock, timer, humidity sensor,
rain sensor, light sensor, etc.
[0066] The method of the present invention may also include, when
the air duct further has an additional intermediate port and a
bypass valve capable of opening and closing the intermediate port,
maintaining the additional intermediate port open during operation
of the water production system.
[0067] In a specific example embodiment of the present invention, a
water production system may be provided as shown in the drawings,
with various components being selected as follows: two matching
refrigeration systems, each having a 5 hp compressor, a pair of
evaporators with an air flow capacity of 100 pounds of air per
minute, an expansion valve, and a pair of condensers with an air
flow capacity of 200 pounds of air per minute. The fan was selected
having a capacity of 200 pounds of air per minute, and adjustable
bypass valves were provided with a controller set to open them
above an ambient air temperature selected at 78 degrees Fahrenheit,
or 25.6 degrees Celsius. The resulting example embodiment produced
approximately 0.5 liters of water per minute.
[0068] With specific reference to FIGS. 9 and 10, another
embodiment of a water production system is depicted, showing an
evaporator 44, condenser 46, expansion valve 48, fan housing 50, as
well as an air bypass port 52 enclosed by an air bypass duct
54.
[0069] Several advantages may be achieved with the present
invention, including for example enhanced efficiency, lowering the
amount of energy used to produce a specific amount of water when
operating the water production system. Another advantage of the
present invention includes broadening the possible environments,
geographical areas, weather conditions, and times of day when the
water production system of the present invention may be used
effectively and efficiently. Moreover, the present invention may
provide the advantage of balancing the respective capacities of the
various refrigeration system components, such as for example the
capacity of one or more evaporators and condensers.
[0070] It should be understood that an unlimited number of
configurations for the present invention could be realized. The
foregoing discussion describes merely exemplary embodiments
illustrating the principles of the present invention, the scope of
which is recited in the following claims. In addition, unless
otherwise stated, all of the accompanying drawings are not to
scale. Those skilled in the art will readily recognize from the
description, claims, and drawings that numerous changes and
modifications can be made without departing from the spirit and
scope of the invention.
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