U.S. patent application number 15/317781 was filed with the patent office on 2017-04-20 for air supply system and method.
The applicant listed for this patent is THERMO KING CORPORATION. Invention is credited to Radim CERMAK, Lubos FOREJT, Jiri ZITA.
Application Number | 20170108263 15/317781 |
Document ID | / |
Family ID | 54834330 |
Filed Date | 2017-04-20 |
United States Patent
Application |
20170108263 |
Kind Code |
A1 |
CERMAK; Radim ; et
al. |
April 20, 2017 |
AIR SUPPLY SYSTEM AND METHOD
Abstract
An air supply system of an atmosphere control system is
provided. The air supply system may incorporate features to
condition an air stream before the air stream is directed toward an
air separation device. A temperature of the air stream to the air
separation device may be reduced to help condense moisture in the
air stream. The air stream with the lowered temperature may be
directed through a moisture removal device to help remove moisture
in the air stream. The air stream may also be directed through a
particle removal device to help remove particles in the air stream.
The air stream may be directed through a heat recovery device to
regulate the temperature of the air stream before being directed to
the air separation device.
Inventors: |
CERMAK; Radim; (Prague,
CZ) ; ZITA; Jiri; (Brno, CZ) ; FOREJT;
Lubos; (Statenice, CZ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
THERMO KING CORPORATION |
Minneapolis |
MN |
US |
|
|
Family ID: |
54834330 |
Appl. No.: |
15/317781 |
Filed: |
June 11, 2015 |
PCT Filed: |
June 11, 2015 |
PCT NO: |
PCT/US2015/035368 |
371 Date: |
December 9, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62010757 |
Jun 11, 2014 |
|
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|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F25D 17/042 20130101;
F25D 11/003 20130101; F25B 7/00 20130101; F25D 2317/0411 20130101;
F25B 9/004 20130101 |
International
Class: |
F25D 17/04 20060101
F25D017/04; F25D 11/00 20060101 F25D011/00 |
Claims
1. An air supply system, comprising: a first heat exchanger; a
second heat exchanger; and a moisture reduction device; wherein the
first heat exchanger is configured to lower a temperature of an air
stream supplied to the air supply system, the moisture reduction
device is configured to remove moisture in the air stream after the
air stream is directed out of the first heat exchanger; and the
second heat exchanger is configured to raise the temperature of the
air stream after the air stream is directed out of the moisture
reduction device.
2. The air supply system of claim 1, further comprising: a particle
reduction device, wherein the particle reduction device is
configured to remove particles in the air stream after the air
stream is directed out of the moisture reduction device.
3. The air supply system of claim 1, wherein an air stream to the
air supply system is provided by an air compressor.
4. The air supply system of claim 1, wherein the first heat
exchanger is configured to form a heat exchange relationship with a
cold part of a refrigeration system.
5. The air supply system of claim 4, wherein the first heat
exchanger is configured to form the heat exchange relationship with
an evaporator of the refrigeration system.
6. The air supply system of claim 1, wherein the first heat
exchanger is configured to be positioned inside a temperature
controlled storage unit.
7. The air supply system of claim 5, wherein the first heat
exchanger is configured to be positioned in an airflow inside the
temperature controlled storage unit.
8. The air supply system of claim 1, wherein the second heat
exchanger is configured to form a heat exchange relationship with a
hot part of a refrigeration system.
9. The air supply system of claim 1, wherein the second heat
exchanger is configured to form a heat exchange relationship with a
condenser of the refrigeration system.
10. The air supply system of claim 3, wherein the second heat
exchanger is configured to form a heat exchange relationship with
an air stream compressed by the air compressor.
11. The air supply system of claim 1, further comprising: a first
temperature sensor configured to measure a first temperature of the
air stream directed out of the first heat exchanger; and a second
temperature sensor configured to measure a second temperature of
the air stream directed out of the second heat exchanger, wherein
the air supply system is configured so that the first temperature
and the second temperature meet desired values.
12. The air supply system of claim 1, wherein the air stream
directed out of the second heat exchanger is directed to an air
separation device, wherein the air separation device removes carbon
dioxide from the air stream and includes at least one of a pressure
swing membrane, a cryogenic distillation device, a sorption device,
and a catalytic conversion device.
13. A transport unit, comprising: a transport refrigeration unit;
an air supply system, comprising: a first heat exchanger; a second
heat exchanger; and a moisture reduction device; wherein the first
heat exchanger is configured to lower a temperature of an air
stream supplied to the air supply system, the moisture reduction
device is configured to remove moisture in the air stream after the
air stream is directed out of the first heat exchanger; and the
second heat exchanger is configured to raise the temperature of the
air stream after the air stream is directed out of the moisture
reduction device; and an air separation device, wherein the air
stream form the air supply system is directed to the air separation
device.
14. The transport unit of claim 13, wherein the transport
refrigeration unit further comprising an evaporator, wherein the
first heat exchanger is configured to form a heat exchange
relationship with the evaporator of the transport refrigeration
unit.
15. The transport unit of claim 13, further comprising a cargo
space, wherein the first heat exchanger is configured to be
positioned inside the cargo space of the transport unit.
16. The transport unit of claim 13, wherein the transport
refrigeration unit further comprises a condenser, wherein the
second heat exchanger is configured to form a heat exchange
relationship with the condenser of the transport refrigeration
unit.
17. The transport unit of claim 13, further comprising: a
compressor configured to provide the air stream to the air supply
system, wherein the second heat exchanger is configured to form a
heat exchange relationship with the air stream provided by the air
compressor.
18. A method of conditioning an air stream for an air separation
device, comprising: providing an air stream; lowering a temperature
of the air stream; removing moisture from the air stream with the
lowered temperature; and increasing the temperature of the air
stream after removing moisture from the air stream.
19. The method of conditioning the air stream of claim 16, further
comprising: removing particles from the air stream after removing
moisture from the air stream.
20. The method of conditioning the air stream of claim 16, wherein
lowering the temperature of the air stream includes forming a heat
exchange relationship with an evaporator of a transport
refrigeration unit.
21. The transport unit of claim 13, wherein the air separation
device removes carbon dioxide from the air stream and includes at
least one of a pressure swing membrane, a cryogenic distillation
device, a sorption device, and a catalytic conversion device.
22. The method of claim 18, further comprising removing carbon
dioxide from the air stream using at least one of a pressure swing
membrane, a cryogenic distillation device, a sorption device, and a
catalytic conversion device.
Description
FIELD
[0001] The disclosure herein relates to an air supply system of an
atmosphere control system such as, for example, in a storage unit.
More specifically, the disclosure is directed to an air supply
system that may include features to help condition an air stream
before the air stream is directed through an air separation device
(e.g. a nitrogen separation system), and a method thereof.
BACKGROUND
[0002] In a storage unit (e.g. a transport unit), atmosphere in a
storage space of the storage unit may be controlled to help prolong
the shelf life of perishable goods such as, for example, fruits and
vegetables. In some cases, for example, an atmosphere control
system may be configured to separate nitrogen from the air and
supply the nitrogen to the storage space, so that an oxygen level
and/or carbon dioxide level in the storage space may be controlled.
A nitrogen and/or CO2 and/or O2 separation device, such as a
nitrogen separation membrane, may be included in the atmosphere
control system to help separate the nitrogen from the air.
SUMMARY
[0003] Embodiments as disclosed herein provide systems, apparatuses
and methods to condition an air stream before the air stream is
directed through an air separation device to help increase or
maintain an efficiency of the air separation device.
[0004] In some embodiments, an atmosphere control system, for
example, in a storage unit (e.g. a transport unit) may generally
include an air supply system and an air separation device. The air
supply system may incorporate features to condition an air stream
before the air stream is directed toward the air separation device.
The air supply system may be configured, for example, to help
regulate a temperature of the air stream, and/or remove moisture
and/or particles from the air stream. By regulating a temperature
of the air stream, a separation efficiency of the air separation
device can be increased and an overall performance of the
atmosphere control system can be increased. The air supply system
may help increase the efficiency and/or lifespan of the air
separation system. The air supply system may also form a heat
exchange relationship with a refrigeration unit (e.g. a transport
refrigeration unit (TRU)) so that a cooling or hot part of the
refrigeration system may be used to condition the air stream in the
air supply system.
[0005] In some embodiments, the air supply system may include a
first heat exchanger, a second heat exchanger, and a moisture
reduction device. In some embodiments, the first heat exchanger may
be configured to lower a temperature of an air stream supplied to
the air supply system. Lowering the temperature of the air stream
may help saturate the moisture in the air stream to form droplets,
which can help remove the moisture from the air stream.
[0006] In some embodiments, the moisture reduction device may be
configured to remove moisture (e.g. droplets) in the air stream
after the temperature of the air stream is reduced in the first
heat exchanger. In some embodiments, the second heat exchanger may
be configured to raise the temperature of the air stream after the
air stream is directed out of the moisture reduction device.
[0007] In some embodiments, the air supply system may include a
particle reduction device, which may be configured to remove
particles in the air stream. In some embodiments, the particle
reduction device may be positioned downstream of the moisture
reduction device to receive the air stream. In some embodiments,
the air supply system may also include a chemical pollution
reduction device (e.g., an activated carbon filter) for removing
chemical pollution (e.g., oil vapors, ozone, hydrocarbons, etc.).
In these embodiments, the device can be positioned downstream of
the particle reduction device.
[0008] In some embodiments, the first heat exchanger may be
configured to form a heat exchange relationship with a cold part of
the refrigerant system such as, for example, an evaporator of the
refrigeration. The cold part of the refrigeration system generally
refers to components, devices or refrigerant lines of the
refrigeration system that may carry a refrigerant having a
temperature that is lower than the ambient temperature. In some
embodiments, the first heat exchanger may be configured to be
positioned inside a storage space of the temperature controlled
storage unit so that the relatively cold air in the storage space
of the storage unit may be used to lower the temperature of the air
stream.
[0009] In some embodiments, the second heat exchanger may be
configured to form a heat exchange relationship with a hot part of
the refrigeration system such as, for example, a condenser of the
refrigeration system.
[0010] In some embodiments, an air compressor may be configured to
provide an air stream to the air supply system. In some
embodiments, the second heat exchanger may be configured to form a
heat exchange relationship with the air stream provided by the air
compressor.
[0011] In some embodiments, the air supply system may include a
first temperature sensor configured to measure a first temperature
of the air stream directed out of the first heat exchanger and a
second temperature sensor configured to measure a second
temperature of the air stream directed out of the second heat
exchanger.
[0012] In some embodiments, a method of conditioning an air stream
for an air separation device may include providing an air stream;
lowering a temperature of the air stream; removing moisture from
the air stream with the lowered temperature; and increasing the
temperature of the air stream after removing moisture from the air
stream.
[0013] In some embodiments, the method of conditioning the air
stream may include removing particles from the air stream. In some
embodiments, removing particles from the air stream may be
conducted after removing moisture from the air stream. Also, in
some embodiments, an additional filter can be provided to remove
chemical pollution from the air stream.
[0014] In some embodiments, lowering the temperature of the air
stream may include forming a heat exchange relationship between the
air stream with an evaporator of a refrigeration system. In some
embodiments, increasing the temperature of the air stream after
removing moisture from the air stream may include forming a heat
exchange relationship between the air stream with a condenser of a
refrigeration system. In some embodiments, increasing the
temperature of the air stream after removing moisture from the air
stream may include forming a heat exchange relationship between the
air stream and the air stream compressed by a compressor.
[0015] In some embodiments, the storage unit can be a TRU.
[0016] Other features and aspects of the systems, methods, and
control concepts will become apparent by consideration of the
following detailed description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Reference is now made to the drawings in which like
reference numbers represent corresponding parts throughout.
[0018] FIG. 1 illustrates one embodiment of an atmosphere control
system, which includes an air supply system configured to condition
an air stream supplied to an air separation system of the
atmosphere control system.
[0019] FIG. 2 illustrates an atmosphere control system, according
to another embodiment.
[0020] FIG. 3 illustrates an atmosphere control system, according
to yet another embodiment.
[0021] FIG. 4 illustrates an atmosphere control system, according
to another embodiment.
[0022] FIG. 5 illustrates a truck trailer that is equipped with an
atmosphere control system.
DETAILED DESCRIPTION
[0023] Atmosphere in a storage unit (e.g. a cargo space of a
transport unit) may be controlled to help, for example, prolong the
shelf life of perishable goods. In some cases, for example,
components separated from air (e.g. nitrogen, and/or CO2, and/or
O2) may be supplied to the storage space to replace oxygen and/or
carbon dioxide in the storage space, which may help reduce a
ripening effect of the perishable goods. A nitrogen separation
device, such as a nitrogen separation membrane, may be used to help
separate nitrogen from the air. A separation efficiency of the
nitrogen separation device, such as the nitrogen separation
membrane, may be affected, for example, by a temperature, humidity
and or a particle content of the air supplied to the nitrogen
separation device.
[0024] An air supply system that incorporates features to condition
an air stream before the air stream is directed through an air
separation device (e.g. a nitrogen separation membrane) and a
method of conditioning the air stream supplied to the air
separation device are describe herein. In some embodiments, a
temperature of the air stream may be reduced to help saturate
moisture in the air stream. In some embodiments, the air stream
with the lowered temperature may be directed through a moisture
removal device to help remove moisture in the air stream. In some
embodiments, the air stream may be directed through a particle
removal device to help remove particles in the air stream. In some
embodiments, the air supply system may also be directed through a
chemical pollution reduction device (e.g., an activated carbon
filter) for removing chemical pollution (e.g., oil vapors, ozone,
hydrocarbons, etc.). In some embodiments, the air stream may be
directed through a heat recovery device to regulate the temperature
of the air stream before the air stream being directed through an
air separation device. In some embodiments, the air stream may be
directed through an air separation device such as, for example, a
nitrogen separation membrane.
[0025] References are made to the accompanying drawings that form a
part hereof, and in which is shown by way of illustration of the
embodiments in which the embodiments may be practiced. It is to be
understood that the term used herein are for the purpose of
describing the figures and embodiments and should not be regarded
as limiting the scope. The term "air separation" is generally
defined as separation of components (e.g. nitrogen, oxygen, carbon
dioxide and/or argon) from atmosphere air.
[0026] Referring to FIG. 1, an atmosphere control system for a
storage unit 120 is described. The atmosphere control system may
include an air supply system 100, an air separation device 110 and
an air compressor 145. The air supply system 100 is configured to
condition an air stream 105 (illustrated in FIG. 1 as arrows)
before the air stream 105 is provided to the air separation device
110 (e.g. a nitrogen separation membrane). The air separation
device 110 may be configured to, for example, separate nitrogen
from the air stream 105 and provide the separated nitrogen to a
storage space 122 of a storage unit 120. It is to be appreciated
that the air separation device 110 may be configured to separate
other type(s) of gas from the air such as, for example, oxygen,
argon, carbon dioxide, or other rare inert gases. In some
embodiments, the air separation device 110 may be configured to
separate water vapor, ethylene, etc. In some embodiments, the air
separation device 110 may be configured to separate different
components of the air at, for example, different rates.
[0027] The term "air separation" refers to a process to separate
atmospheric air into different components, typically nitrogen and
oxygen, and sometimes also argon, carbon dioxide, or other rare
inert gases. Various types of air separation device 110 may be
used. For example, the air separation device 110 may be a pressure
swing membrane, or a cryogenic distillation device. It is to be
appreciated that other methods and systems may also be used to
remove components from the air, such as for example, sorption
(absorption/desorption or chemisorption) or catalytic conversion.
It is to be appreciated that the atmosphere control system as
described herein can be configured to be suitable for various
methods and systems for air separation or components removal.
[0028] The air stream 105 may be provided to the air supply system
100 by, for example, the air compressor 145. The compression of the
air stream 105 by the air compressor 145 may increase a temperature
of the air stream. In addition, the air stream 105 may include some
moisture, and/or solid and liquid particles. When the air
compressor 145 compresses the air stream 105, the moisture and
particle concentrations in the air stream 105 may be increased. An
efficiency of the air separation device 110 may be affected by, for
example, the moisture and/or particle content of the air stream
105. To help increase and/or maintain the efficiency of the air
separation device 110, the air supply system 100 may be configured
to include features to help condition the air stream 105, which may
include removing moisture and/or particles from and/or regulating a
temperature of the air stream 105, so that the air stream 105
provided to the air separation device 110 may have desired air
parameters (e.g. a moisture content, a particle content, a
temperature) to for desired performance of the air separation
device 110.
[0029] Generally, the air supply system 100 may be configured to
lower the temperature of the air stream 105 to increase a relative
humidity and/or achieve air saturation with the moisture content.
The moisture may start to create droplets, which may be removed
relatively easily. The same principle may not only apply to a water
content, but may also apply to, for example, oil fume or other
types of vapor. The droplet formation may also help reduce particle
content in the air stream 105. After removing the moisture and/or
particle content, the air supply 100 may be configured to condition
(e.g. heat up) the air stream 105 so that the temperature of the
air stream 105, for example, may be in a desired range for the
desired performance of the air separation device 110.
[0030] The air supply system 100 illustrated in FIG. 1 includes a
first heat exchanger 130, a moisture reduction device 132, a
particles reduction device 134, and a second heat exchanger 136.
The air supply system 100 also includes a first valve 137 and a
second valve 139. The first and second valves 137, 139 may be
configured to regulate the air stream 105 (e.g. directions and/or
an amount of the air stream 105) in the air supply system 100. The
air supply system 100 can also include a first temperature sensor
141 and a second temperature sensor 143.
[0031] The air stream 105 may be provided to the air supply system
100 by the air compressor 145. The first heat exchanger 130 may be
configured to lower the temperature of the air stream 105 when the
air stream 105 flows through the first exchanger 130. The first
heat exchanger 130 may be, for example, thermally coupled to a cold
part of a refrigeration system 140 so that the first heat exchanger
130 forms a heat exchange relationship with the cold part of the
refrigeration system 140. In some embodiments, the first heat
exchanger 130 can form a heat exchange relationship with, for
example, heat exchanger tubes of an evaporator of the refrigeration
system 140, so that cold refrigerant in the evaporator of the
refrigeration system 140 may help lower the temperature of the air
stream 105 in the first heat exchanger 130. The first heat
exchanger 130 may be, for example, a tube-in-shell or tube-by-tube
design. The cold part of the TRU generally refers to components,
devices or refrigerant lines of the TRU that may carry a
refrigerant having a temperature that is lower than the ambient
temperature. In some embodiments, the first heat exchanger 130 may
not form a direct heat exchange relationship with the refrigeration
system 140. The first heat exchanger 130 may be, for example,
positioned in the storage space 122, and cold air in the storage
space 122 may help lower the temperature of the air stream 105 in
the first heat exchanger 130. In some embodiments, the first heat
exchanger 130 may be positioned in an airflow directed out of the
refrigeration system 140.
[0032] The air stream 105 may then be directed through the moisture
reduction device 132 to remove, for example, water droplets in the
air stream 105. The air stream 105 may be directed through the
particle reduction device 134 to remove, for example, particles in
the air stream 105. It is to be appreciated that in some
embodiments, the particle reduction device 134 may also be
positioned upstream of the moisture reduction device 132.
[0033] The air stream 105 leaving the particle reduction device 134
may be, for example, directed through the second heat exchanger 136
to help regulate the temperature of the air stream 105 before the
air stream 105 is directed through the air separation device 110.
Typically, the temperature of the air stream 105 directed out of
the particle reduction device 134 may be relatively low, because
the temperature of the air stream 105 may be lowered in the first
heat exchanger 130. The second heat exchanger 136 may be configured
to increase the temperature of the air stream 105 to, for example,
the desired temperature for the desired performance of the air
separation device 110.
[0034] In the illustrated embodiment of FIG. 1, the second heat
exchanger 136 may help form a heat exchange relationship between
the air stream 105b directed out of the particle reduction device
134 and the air stream 105a directed out of the air compressor 145.
Because the air stream 105a directed out of the air compressor 145
typically has a relatively high temperature, the second heat
exchanger 136 may help increase the temperature of the air stream
105b directed out of the particular reduction device 134, which may
have the relatively low temperature. It is to be appreciated that
the second heat exchanger 136 may also be thermally coupled to
other heat source(s) that is suitable for heating the air stream
105b, such as forming a heat exchange relationship with a hot part
(e.g. a condenser) of the refrigeration system 140. The hot part of
the refrigeration system generally refers to components, devices or
refrigerant lines of the TRU that may carry a refrigerant having a
temperature that is higher than the ambient temperature.
[0035] In some embodiments, there is no need to regulate an amount
and/or direction of air stream 105. In some embodiments, it may be
desirable to regulate the amount and/or direction of air stream
105. It is to be appreciated that one or more valves may be used in
the air supply system 100 to regulate, for example, an amount
and/or a direction of the air stream 105. In the illustrated
embodiment of FIG. 1, the first valve 137 and the second valve 139
may be configured so that the air stream 105 may by-pass the first
and/or second heat exchangers 130, 136 and be directed through the
moisture reduction device 132 directly. The first and second valves
137, 139 may also be configured to regulate the amount of air
stream 105 directed to the first and/or second heat exchangers 130,
136. For example, the first and second valve 137, 139 may be
three-way valves and the amount of air stream directed through the
first heat exchanger 130 and/or the second heat exchanger 136 may
be regulated.
[0036] In some embodiments, the first valve 137, the second valve
139 and the line connecting the first and second valves 137, 139
may not be necessary. The air stream 105 can be directed into the
second heat exchanger 136, the first heat exchanger 130 and the
moisture reduction device 132 without going through a valve
configured to control an amount or direction of the air stream
105.
[0037] It is to be appreciated that the embodiment in FIG. 1 is
exemplary. Generally, one or more valves may be included in the air
supply system 100 so that the first and/or the second heat
exchangers 130, 136 may be by-passed. For example, when the
environment is relatively warm, the second heat exchanger 136 may
be by-passed. Generally, the factors affecting the decision on
whether to by-pass the second heat exchanger 136 may include: an
amount of heat transferred in the first and/or second heat
exchangers 130, 136, the temperature of the air stream 105 directed
through the air compressor 145, an ambient temperature, a cargo
temperature, a space temperature of the storage space 122, an
operation condition of the air supply system 100 and/or an
operation mode (e.g. on or off) of the refrigeration system
140.
[0038] In operation, the first and second valves 137, 139 may be
modulated to control the air stream 105 enters and/or by-passes the
first and/or second heat exchangers 130, 136. By controlling the
amount of air stream 105 entering or by-passing the first and/or
second heat exchangers 130, 136, the temperature of the air stream
105 may be controlled.
[0039] In the illustrated embodiment of FIG. 1, the air supply
system 100 includes the first and second temperature sensors 141,
143. The first and second valves 137, 139 may be modulated so that
temperatures measured by the first and/or second temperature
sensors 141, 143 may be at desired temperatures. The first
temperature sensors 141 may be configured to measure a first
temperature of the air stream 105 before the air stream 105 is
directed through the moisture reduction device 132. The first
temperature of the air stream 105 may be, for example, a
temperature that is at or lower than a saturation temperature of
the moisture in the air stream 105. The valves 137, 139 may be
modulated and/or throttled (e.g. on and off) to meet the desired
first temperature.
[0040] The first temperature sensor 141 can help provide
temperature information of the air stream 105 before the air stream
105 is directed into the moisture reduction device 132. It is to be
appreciated that the first temperature sensor 141 is optional, and
is not necessary in some embodiments.
[0041] The second temperature sensor 143 may be configured to
measure a second temperature of the air stream 105 before the air
stream 105 is directed through the air separation device 110. The
second temperature of the air stream 105 may be, for example, a
desired temperature for obtaining optimal efficiency of the air
separation device 110. The valves 137, 139 may also be modulated
and/or throttled (e.g. on and off) to meet the desired second
temperature.
[0042] It is to be appreciated that the temperature of the air
stream 105 may also be regulated by regulating the first and/or
second heat exchangers 130, 136. For example, by regulating an
amount of heat exchanged in the first and/or second heat exchangers
130, 136.
[0043] The air supply system 100 provides a way to regulate the
temperatures of the air stream 105. The air supply system 100 may
be configured to lower the temperature of the air stream 105 so as
to help remove moisture content from the air stream 105, and/or
provide the desired temperature of the air stream 105 for the air
separation device 110. The air compressor 145 configured to provide
the air stream 105 to the air supply system 100 may be a variable
speed or a fixed speed compressor. By using the temperature sensors
141, 143 to measure the temperatures of the air stream 105, and
regulating the air supply system 100 based on the measured
temperatures, the temperatures of the air streams 105 directed
toward the moisture reduction device 132 and the air separation
device 110 may be controlled to meet the desired temperatures. This
may help increase the efficiency and/or the lifespan of the air
separation device 110.
[0044] In some embodiments, the air compressor 145 may be a
variable speed compressor that can regulate a temperature of the
air stream 105 by changing the speed of the compressor. Generally,
the temperature of the air stream 105 is relatively high when the
operation speed of the variable speed air compressor 145 is
relatively high. However, using the variable speed compressor 145
to change the temperature of the air stream 105 may affect an
amount of the air stream 105 provided to the air separation device
110. The air supply system 100 as disclosed herein may add another
way to regulate the temperature of the air stream 105 without
affecting the amount of air stream 105 provided to the air
separation device 110. In some embodiments, when the air compressor
145 has a fixed operation speed, the temperature of the air stream
105 may not be regulated by changing the speed of the compressor.
The air supply system 100 as disclosed herein may regulate the
temperature of the air stream 105 without changing the operation
speed of the air compressor 145 or affecting the amount of the air
stream 105 provided to the air separation device 110.
[0045] A method of conditioning an air stream for an air separation
device may include: providing an air stream (e.g. the air stream
105 provided by the air compressor 145); lowering a temperature of
the air stream (e.g. lowering the temperature of the air stream 105
in the first heat exchanger 130); removing moisture from the air
stream with the lowered temperature (e.g. removing the moisture in
the air stream 105 in the moisture reduction device 132; and
increasing the temperature of the air stream after removing
moisture from the air stream (e.g. increasing the temperature of
the air stream 105 in the second heat exchanger 136).
[0046] In some embodiments, the method of conditioning the air
stream may include removing particles from the air stream (e.g.
removing the particles from the air stream 105 in the particle
reduction device 134). In some embodiments, removing particles from
the air stream may be conducted after removing moisture from the
air stream.
[0047] In some embodiments, lowering the temperature of the air
stream may include forming a heat exchange relationship between the
air stream and a cold part (e.g. an evaporator) of a refrigeration
system. In some embodiments, increasing the temperature of the air
stream after removing moisture from the air stream may include
forming a heat exchange relationship between the air stream with a
hot part (e.g. a condenser) of a refrigeration system. In some
embodiments, increasing the temperature of the air stream after
removing moisture from the air stream may include forming a heat
exchanger relationship between the air stream and the air stream
compressed by an air compressor (e.g. the air stream compressed by
the air compressor 145).
[0048] It is to be appreciated that in some embodiments, an
operational condition(s) (e.g. purity and/or concentration of air
separated by the air separation device 110 may be measured. The
measurement can help protect the air separation device 110 from
abnormal operation. The embodiments as disclosed herein can help
protect the air separation device 110 from, for example, water
damage. The embodiments as disclosed herein can also help the
efficiency of the air separation device 110 by regulating the
temperature of the air stream 105 directed into the air separation
device 110.
[0049] FIGS. 2-4 illustrate several additional embodiments of an
atmosphere control system. It is appreciated that the embodiments
as illustrated in FIGS. 1-4 herein may be combined and/or
altered.
[0050] FIG. 2 illustrates an air supply system 200 that includes a
refrigeration system 240, a three-way valve 235 positioned
downstream of a particles reduction device 234, and upstream of a
second heat exchanger 236. The three-way valve 235 may direct an
air stream 205 into an air separation device 210 without going to a
second heat exchanger 236. When, for example, an atmosphere
temperature is relatively high, the second heat exchanger 236 may
not be necessary to achieve a desired air stream temperature for
the air separation device 210. The three-way valve 235 may be used
to direct the air stream through the air separation device 210,
bypassing the second heat exchanger 236. The air supply system 200
can also include a temperature sensor 243.
[0051] FIG. 3 illustrates another air supply system 300 that is
configured to direct an air stream 305 through a heat exchanger 338
that is thermally coupled to a condenser 350 of a refrigeration
system 340. Refrigerant in the condenser 350 may be directed
through the third heat exchanger 338 to exchange heat with an air
stream 305 in the third heat exchanger 338. In the illustrated
embodiment, an expansion device 355 may be used to expand the
refrigerant from the condenser 350 to lower the temperature of the
refrigerant flowing into the third heat exchanger 338. By
controlling the expansion device 355 to regulate for example a flow
rate, direction, and/or temperature of the refrigerant, desired
heat exchange in the third heat exchanger 338 may be achieved,
which can help the air stream 305 to maintain or reach a desired
temperature when entering the air separation device 310. The air
supply system 300 can also include other heat exchanger(s), e.g. a
second heat exchanger 336, to regulate temperature of the air
stream 305.
[0052] FIG. 4 illustrates another air supply system 400 where a
first heat exchanger 430 may be thermally coupled to a
refrigeration system 440 downstream of an expansion device 460 of
the refrigeration system 440. Relatively cold refrigerant (e.g.
refrigerant expanded by the expansion device 460) can be directed
through the first heat exchanger 430 to exchange heat with an air
stream 405. In the illustrated embodiment, the first heat exchanger
430 is also in fluid communication with a flow control device 461
configured to control, for example, a flow rate of the refrigerant.
By controlling the flow control device 461 and/or the expansion
device 460, a flow rate, direction, and/or a flow temperature of
the refrigerant entering the first heat exchanger 430 may be
controlled to achieve a desired amount of heat exchange in the
first heat exchanger 430. This can help control the temperature of
the air stream 405 entering a moisture removal device 432.
[0053] FIG. 5 illustrates a trailer truck 530 that is equipped with
a TRU 532 and an atmosphere control system 560, which may be
configured to regulate air parameters inside a cargo space 522 of a
trailer 520. In some embodiments, for example, the atmosphere
control system 560 may be configured to increase a nitrogen
concentration and reduce an oxygen concentration and/or a carbon
dioxide concentration in the cargo space 522.
[0054] The atmosphere control system 560 includes an air supply
system 500 and an air separation device 510. The air supply system
500 may be configured to condition an air stream (such as, for
example, the air stream 105 in FIG. 1) being directed toward the
air separation device 510, so that the air stream directed to the
air separation device 510 may have an optimal parameter(s) for the
operation of the air separation device 510. The air supply system
500 may be configured to, for example, remove moisture and/or
particles from the air stream, and/or regulate a temperature of the
air stream.
[0055] The atmosphere control system 560 may be integrated into the
TRU 532, with the appreciation that the atmosphere control system
560 may be separate from the TRU 532. In some embodiments, the
atmosphere control system 560 may form a heat exchange
relationship(s) with the TRU 532, so that a cold part (e.g. an
evaporator) and/or a hot part (e.g. a condenser) may be used to
condition (cool down and/or heat up) the air stream in the
atmosphere control system 560.
[0056] It is to be appreciated that the embodiments as described
herein work with other types of transport unit such as, for
example, a railway car, a shipping container, or an airplane cargo
unit. The embodiments as described herein may also be used with a
stationary storage unit such as, for example, a refrigerator, or a
cold room.
[0057] It is to be appreciated that the embodiments as described
herein may work with other types of air separation devices. For
example, some membranes may be configured to separate other
components from the atmosphere air. Generally, the embodiments as
disclosed herein provide systems, apparatuses and methods to
condition an air stream before the air stream is directed through
an air separation device to help increase or maintain an efficiency
of the air separation device.
[0058] Aspects
[0059] Any of aspects 1-12 can be combined with any of aspects
13-20. Any of aspects 13-17 can be combined with any of aspects
18-20.
Aspect 1. An air supply system, comprising: [0060] a first heat
exchanger; [0061] a second heat exchanger; and [0062] a moisture
reduction device; [0063] wherein the first heat exchanger is
configured to lower a temperature of an air stream supplied to the
air supply system, [0064] the moisture reduction device is
configured to remove moisture in the air stream after the air
stream is directed out of the first heat exchanger; and [0065] the
second heat exchanger is configured to raise the temperature of the
air stream after the air stream is directed out of the moisture
reduction device. Aspect 2. The air supply system of aspect1,
further comprising: [0066] a particle reduction device, wherein the
particle reduction device is configured to remove particles in the
air stream after the air stream is directed out of the moisture
reduction device. Aspect 3. The air supply system of any of aspects
1-2, wherein an air stream to the air supply system is provided by
an air compressor. Aspect 4. The air supply system of any of
aspects 1-3, wherein the first heat exchanger is configured to form
a heat exchange relationship with a cold part of a refrigeration
system. Aspect 5. The air supply system of any of aspect 4, wherein
the first heat exchanger is configured to form the heat exchange
relationship with an evaporator of the refrigeration system. Aspect
6. The air supply system of any of aspects 1-5, wherein the first
heat exchanger is configured to be positioned inside a temperature
controlled storage unit. Aspect 7. The air supply system of any of
aspects 5-6, wherein the first heat exchanger is configured to be
positioned in an airflow inside the temperature controlled storage
unit. Aspect 8. The air supply system of any of aspects 1-7,
wherein the second heat exchanger is configured to form a heat
exchange relationship with a hot part of a refrigeration system.
Aspect 9. The air supply system of any of aspects 1-8, wherein the
second heat exchanger is configured to form a heat exchange
relationship with a condenser of the refrigeration system. Aspect
10. The air supply system of any of aspects 3-9, wherein the second
heat exchanger is configured to form a heat exchange relationship
with an air stream compressed by the air compressor. Aspect 11. The
air supply system of any of aspects 1-10, further comprising:
[0067] a first temperature sensor configured to measure a first
temperature of the air stream directed out of the first heat
exchanger; and [0068] a second temperature sensor configured to
measure a second temperature of the air stream directed out of the
second heat exchanger, [0069] wherein the air supply system is
configured so that the first temperature and the second temperature
meet desired values. Aspect 12. The air supply system of any of any
of aspects 1-11, wherein the air stream directed out of the second
heat exchanger is directed to an air separation device. Aspect 13.
The air supply system of any of aspects 1-12, wherein the first
heat exchanger is coupled to a refrigeration system so as to direct
a portion of expanded refrigerant into the first heat exchanger.
Aspect 14. The air supply system of any of aspects 1-13 further
comprising: [0070] a third heat exchanger positioned downstream of
the second heat exchanger; wherein the third heat exchanger is
coupled to a refrigerant system so as to direct a portion of
refrigerant compressed by a compressor of the refrigerant system
into the third heat exchanger, and exchange heat with the air
stream directed through the third heat exchanger. Aspect 15. A
transport unit, comprising: [0071] a transport refrigeration unit;
[0072] an air supply system, comprising: [0073] a first heat
exchanger; [0074] a second heat exchanger; and [0075] a moisture
reduction device; [0076] wherein the first heat exchanger is
configured to lower a temperature of an air stream supplied to the
air supply system, [0077] the moisture reduction device is
configured to remove moisture in the air stream after the air
stream is directed out of the first heat exchanger; and [0078] the
second heat exchanger is configured to raise the temperature of the
air stream after the air stream is directed out of the moisture
reduction device; and [0079] an air separation device, wherein the
air stream form the air supply system is directed to the air
separation device. Aspect 16. The transport unit of aspect 15,
wherein the transport refrigeration unit further comprising an
evaporator, [0080] wherein the first heat exchanger is configured
to form a heat exchange relationship with the evaporator of the
transport refrigeration unit. Aspect 17. The transport unit of any
of aspects 15-16, further comprising a cargo space, [0081] wherein
the first heat exchanger is configured to be positioned inside the
cargo space of the transport unit. Aspect 18. The transport unit of
any of aspects 15-17, wherein the transport refrigeration unit
further comprises a condenser, wherein the second heat exchanger is
configured to form a heat exchange relationship with the condenser
of the transport refrigeration unit. Aspect 19. The transport unit
of any of aspects 15-18, further comprising: [0082] a compressor
configured to provide the air stream to the air supply system,
wherein the second heat exchanger is configured to form a heat
exchange relationship with the air stream provided by the air
compressor. Aspect 20. A method of conditioning an air stream for
an air separation device, comprising: [0083] providing an air
stream; [0084] lowering a temperature of the air stream; [0085]
removing moisture from the air stream with the lowered temperature;
[0086] increasing the temperature of the air stream after removing
moisture from the air stream; and [0087] directing the air stream
into the air separation device. Aspect 21. The method of
conditioning the air stream of aspect 20, further comprising:
[0088] removing particles from the air stream after removing
moisture from the air stream. Aspect 22. The method of conditioning
the air stream of aspects 20-21, wherein lowering the temperature
of the air stream includes forming a heat exchange relationship
with an evaporator of a transport refrigeration unit.
[0089] With regard to the foregoing description, it is to be
understood that changes may be made in detail, without departing
from the scope of the present invention. It is intended that the
specification and depicted embodiments are to be considered
exemplary only, with a true scope and spirit of the invention being
indicated by the broad meaning of the claims.
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