U.S. patent application number 14/248837 was filed with the patent office on 2014-08-07 for device for controlling the gas medium inside a container.
This patent application is currently assigned to Chiquita LLC. The applicant listed for this patent is Chiquita LLC. Invention is credited to Carlos Beltran, Raul Fernandez, Pat Foster, Julio Urquiaga.
Application Number | 20140220203 14/248837 |
Document ID | / |
Family ID | 37637693 |
Filed Date | 2014-08-07 |
United States Patent
Application |
20140220203 |
Kind Code |
A1 |
Fernandez; Raul ; et
al. |
August 7, 2014 |
DEVICE FOR CONTROLLING THE GAS MEDIUM INSIDE A CONTAINER
Abstract
A device for controlling the composition inside a
shipping/storage container for produce, such as bananas, is
disclosed. Such atmospheric control is particularly important when
dealing with the ripening of respiring fruit. The device comprises
a chamber surrounded by an outer wall, at least a portion of that
wall made up of a selectively gas-permeable membrane which is in
communication with the outside atmosphere. The chamber also
includes at least two channels which are connected to the
container: one which transmits gas form the chamber to the
container, and one which transmits gas from the container to the
chamber.
Inventors: |
Fernandez; Raul; (Weston,
FL) ; Foster; Pat; (Tamarac, FL) ; Beltran;
Carlos; (Hialeah Gardens, FL) ; Urquiaga; Julio;
(Miami, FL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Chiquita LLC |
Charlotte |
NC |
US |
|
|
Assignee: |
Chiquita LLC
Charlotte
NC
|
Family ID: |
37637693 |
Appl. No.: |
14/248837 |
Filed: |
April 9, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11427201 |
Jun 28, 2006 |
|
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|
14248837 |
|
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Current U.S.
Class: |
426/419 |
Current CPC
Class: |
A23L 3/3445 20130101;
A23B 7/00 20130101; A23V 2002/00 20130101; A23V 2002/00 20130101;
A23V 2250/126 20130101; A23V 2250/101 20130101; A23V 2250/11
20130101; A23V 2200/10 20130101; A23B 7/152 20130101 |
Class at
Publication: |
426/419 |
International
Class: |
A23B 7/00 20060101
A23B007/00 |
Claims
1. (canceled)
2. (canceled)
3. (canceled)
4. (canceled)
5. (canceled)
6. (canceled)
7. (canceled)
8. (canceled)
9. (canceled)
10. (canceled)
11. (canceled)
12. (canceled)
13. (canceled)
14. A method for preserving and ripening produce during shipping
and/or storage comprising the steps of: (a) placing said produce in
a container adapted for the shipping and/or storage of said
produce; (b) providing a device for achieving and maintaining the
required composition of the gas medium within said container to
achieve storage/ripening of said produce in said container; said
device being separate from and located outside said container and
consisting essentially of a chamber surrounded by an outer wall, a
portion of said outer wall being made up of a selectively
gas-permeable membrane which is in direct communication with both
the atmosphere outside the device and the atmosphere outside the
shipping/storage container, wherein the membrane controls the
identity and ratio of gases passing through it into the chamber,
and the contents of said chamber being at substantially atmospheric
pressure; and at least two channels, which are structurally adapted
such that they can be removably attached to said container, one of
which acts to transmit gases from the chamber to the container, and
the other of which acts to transmit gases from the container to the
chamber; and (c) allowing atmospheric gases to flow through the
membrane into the chamber and then into the container, thereby
adjusting the gaseous content in the container.
15. The method according to claim 14 wherein the device includes
valves in one or more of said channels to control the extent and/or
direction of gas flow.
16. The method according to claim 15 wherein the device
additionally comprises a sensor-based control system to control the
inflow and outflow of gases from the chamber.
17. The method according to claim 14 wherein the device includes
one or more fans to assist with the gas flow.
18. The method according to claim 14 wherein the device includes an
additional inlet channel for feeding one or more additional gases
into the chamber.
19. the method according to claim 18 wherein said one or more
additional gases includes ethylene.
20. The method according to claim 19 wherein the produce comprises
bananas.
21. The method according to claim 20 wherein the membrane is
selectively permeable to gases selected from oxygen, carbon
dioxide, and mixtures thereof.
22. The method according to claim 14 wherein the container for
shipping and storage of produce and the device itself comprises a
single entity.
23. The method according to claim 21 wherein the ratio of
permeability values of carbon dioxide:oxygen is about 4.
Description
[0001] This application is based upon and claims priority from U.S.
Provisional Patent Application No. 60/697,722, Fernandez et al.,
filed Jul. 8, 2005, incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The invention is related to container shipping and storage
of produce, in particular, to the means for controlling the gas
composition in such containers.
BACKGROUND OF THE INVENTION
[0003] Transfer of fruits in shipping containers necessitates a
certain composition of a gas medium inside the container. That
composition should change depending upon the type of fruits, the
degree of their ripeness, and the technology for preparation of
these fruits for sale.
[0004] There are known inventions related to the systems for
controlling gas media in shipping containers.
[0005] U.S. Pat. No. 5,333,394, "Controlled atmosphere container
system for perishable products", Herdeman, et al., issued Aug. 2,
1994, includes a description of a system that is connected to the
inlet connecting pipe of the container, allowing control of the gas
medium inside it. The system includes the central source of the gas
medium, which is connected through pipes and channels to a number
of containers into which the required gas medium is pumped.
[0006] U.S. Pat. No. 6,092,430, "Oxygen/carbon dioxide sensor and
controller for a refrigerated controlled atmosphere shipping
container", Liston, et al, issued Jul. 25, 2000, includes a
description of a device for controlling a gas medium in a container
intended for shipping of perishable products, in particular,
fruits. The device includes an inlet connecting pipe, intended for
the intake of atmospheric air, which is first cleaned from dust and
moisture. Then, using a compressor, the air is passed through a
nitrogen-permeable membrane filter. The separated nitrogen is
further directed inside the container. The device is also equipped
with a vessel with carbon dioxide, and with a system for feeding
carbon dioxide into the container. The container is equipped with a
system for controlling carbon dioxide and oxygen content in the gas
medium, and for pumping nitrogen into the container.
[0007] U.S. Pat. No. 6,615, 908, "Method of transporting or storing
perishable product", Bosher, et al., issued Sep. 9, 2003, includes
a description of a device for controlling the gas medium inside a
container. The device includes a diffusion membrane through which
atmospheric air is pulled into the container. The membrane conducts
carbon dioxide, and does not conduct oxygen. The gas medium in the
container is modified by releasing parts of it from the container
through a release valve, and by substituting it for gas that has
passed through the above-mentioned membrane.
[0008] Existing devices for regulation of gas media in containers
involve complicated equipment. They also require significant energy
consumption for passing atmospheric air through filters, and for
generating excessive pressure inside the container necessary to
release the gas medium being substituted through the outlet
valves.
SUMMARY OF THE INVENTION
[0009] The device described here achieves the required composition
of the gas medium in a container for shipping and storage of
produce--in particular, Bananas--and constitutes a simple structure
consuming a relatively small amount of energy.
[0010] The device consists of a gas exchange chamber, the inner
space of which is connected to the inner space of the container
through at least two channels. One of the channels is intended for
intake of the gas medium from the container, while another is
intended for the return of the modified gas medium back into the
container. The inner space of the chamber is also connected with
the external atmosphere via a gas-permeable membrane.
[0011] The gas medium (from the shipping/storage container) enters
the inner space of the chamber through the intake channel. Due to
the presence of the above-mentioned gas-permeable membrane, the gas
exchange between the gas medium of the chamber and the external
atmosphere occurs inside the inner space of the chamber. The nature
of the gas exchange is predetermined by the selective features of
the gas membrane (different permeability with different gases).
Thus, the modification of composition of gas staying in the chamber
will be achieved. The gas medium of the container mixes with the
gas medium of the chamber. Modified gas from the chamber returns to
the container through the channel for return of modified gas
medium. As a result, new portions of the gas medium are
continuously fed into the inner space of the chamber from the
container. The gas medium from the container can pass through the
gas exchange chamber several times, until the gas medium from the
container is modified in such a way that it attains the required
composition (ratio of gases).
[0012] Such a gas exchange process can be used to maintain a
consistent composition of a gas medium in a container when, due to
biological processes of the stored produce (e.g., respiration,
ripening), the composition of the gas medium inside the container
changes. Thus, to store bananas and to avoid their early ripening,
it is necessary to maintain a reduced oxygen/increased CO2 gas
medium (as compared to ambient air) inside the container. However,
bananas respire during storage (take in oxygen and release CO2),
which modifies the required conditions for storing them. In this
case, the described device can be used for maintenance of a
constant ratio of concentration of oxygen and CO2 inside the
container. This is achieved by feeding oxygen from ambient air
through a gas-permeable membrane, into the inner space of the gas
exchange chamber, and feeding the CO2 from the gas exchange chamber
through the membrane, into the ambient air. Determining a definite
ratio of membrane permeability for CO2 and oxygen allows (due to
the gas exchange developing in the chamber) to compensate for the
modification of composition of the gas medium inside the container
caused by banana respiration. As a result, it is possible to
maintain the required ratio of oxygen and CO2 in the gas medium
inside the container.
[0013] The required rate for changing the gas medium inside the
container can be achieved in different ways: for example, based
upon the volume of the inner chamber and the surface area of the
gas-permeable membrane and/or control of the flow rate in the
intake channels and/or return of the gas medium.
[0014] Switching the device on and off, as well as controlling its
operation modes, can be performed by regulating the cross-section
of channels of intake and return of the gas medium, for example,
using shutters or valves.
[0015] The device can be a separate gas exchange chamber, which has
pipe connections intended for connecting the chamber to the
container, for example, using hoses. The device can be used with a
standard shipping container having two pipe connections. One
connection serves for uptake of the gas medium from the container,
the other serves to return the modified gas medium. The inner space
of the gas exchange chamber is connected to the container's pipe
connections, via hoses. The flow of the gas medium through the
chamber is caused by a fan, which is usually provided in a
container for circulating the gas medium inside it. Part of the gas
medium will flow through the uptake pipe connection from the
container, into the inner space of the chamber. The modified gas
medium will be fed into the container through another pipe
connection.
[0016] Such a device for gas medium control with one gas exchange
chamber can serve several containers,
[0017] To intensify the rate of gas exchange, chargers (for
example, fans) can be built into the uptake and return channels of
the gas medium.
[0018] The device can also be a unit connected to the shipping
container. In this case, the design should connect the gas chamber
in such a way that the uptake channel and the return channel are
connected to the corresponding pipe connections of container.
[0019] In another alternative, the device can be part of the actual
shipping container, as a separate section equipped with
corresponding channels intended for gas uptake and return. This
section would be connected to the ambient atmosphere through the
selectively gas-permeable membrane.
[0020] Valves can be installed at the inlet and outlet of the
uptake channel and the return channel; the valves can be controlled
by a sensor-based system that would determine the composition of
the gas medium inside the container, and modify the gas flow
accordingly to meet defined atmospheric compositions.
[0021] In any design alternative of the device, the gas exchange
chamber can have an additional inlet channel for feeding gases into
the inner space of the chamber (gases required for storage of
produce, such as ethylene, for example).
[0022] The above description of the gas exchange chamber is not
exhaustive.
[0023] For example, the device can also be a separate gas exchange
channel, the wall of which contains a selective gas-permeable
membrane. Due to the presence of the membrane, the gas exchange
between the gas medium moving inside the channel along the membrane
and ambient atmosphere, will occur inside the channel. The channel
can vary in shape depending on the needed level of compactness and
length. The required rate for modification of the gas medium inside
the container can be achieved in different ways: selection of the
length of the channel and the surface area of the selectively
gas-permeable membrane, control of the flow rate in the uptake and
return channels. The connection of the device to the container is
similar to that for a gas exchange chamber.
[0024] Specifically, the present invention relates to a device for
providing the required composition of gas medium in a container for
shipping and/or storage of produce, comprising a chamber surrounded
by an outer wall, at least a portion of said wall made up of a
selectively gas-permeable membrane which is in communication with
the outside atmosphere, and at least two channels (which are
capable of being connected to the produce container), one of which
acts to transmit gases from the chamber to the container, and one
of which acts to transmit gases from the container to the
chamber.
[0025] In another embodiment, the present invention relates to a
method for providing a defined composition for the gas medium in a
container for shipping and/or storage of produce using the device
defined above, comprising the steps of: measuring the composition
of the gas medium in the container; comparing the measured
composition against the defined composition (target) of the gas
medium; controlling the flow of gases from the chamber to the
container and/or from the container to the chamber; and repeating
the measuring, comparing and controlling steps until the measured
composition in the container matches the defined composition.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 shows an example of a device for regulation of the
gas medium inside a shipping/storage container, embodied as a
separate gas exchange chamber connected to the container via hoses;
FIG. 2 shows the cross-section of chamber.
[0027] FIG. 3 shows an example of a design embodiment of the gas
exchange chamber with additional chargers, and an additional inlet
for inlet of gas to be mixed with the gas medium of the
container.
[0028] FIG. 4 shows an example of a device, embodied as a section
connected to the main container.
[0029] FIG. 5 shows an example of a device, embodied jointly with
the container as a separate section.
DETAILED DESCRIPTION OF THE INVENTION
[0030] Container (1) (FIG. 1) contains the load, for example, in
the form of packaged fruits (2). Transfer and stirring of gas
medium inside the container is ensured by the charger (3). The
device for control of the gas medium inside the container (1) is
embodied in the form of a chamber (4) with an inner space (5) (see
FIG. 2) and a gas-permeable membrane (6). The membrane separates
the inner space (5) of chamber (4) from the external ambient air. A
connecting pipe (7) of the container (1) and the hose (8) form a
channel for uptake of the gas medium from the container (1) and for
feeding it into the chamber (4). The connecting pipe (9) and the
hose (10) form a channel for return of the modified gas medium from
the chamber (4) to the container (1).
[0031] Valves (11 and 12) are installed on connecting pipes (7 and
9). These valves are connected to the corresponding control system
(not shown in FIG. 1), containing sensors and devices controlling
the operation of the valves (11, 12) and the charger (3).
[0032] The device for controlling the gas medium composition in the
container (2), in the above-described design alternative, operates
as follows:
[0033] To modify the gas medium, the chamber (4) is connected to
connecting pipes (7 and 9) using hoses (8 and 10). Valves (11 and
12) are opened by the control system and if the charger (3) has not
yet been turned on by the time, it is switched on. The gas medium
from the container (1) begins to enter the inner space (5) of the
chamber (4) through the connecting pipe (7) and hose (8).
[0034] The gas exchange between the gas remaining in the inner
space (5) of the chamber (4) and external atmospheric air occurs
via the gas-permeable membrane (6). The direction of the gas
exchange is determined by the difference in concentration of gas
medium components of the container (1) and external ambient air.
The circulation of the gas medium of the container (1) through the
chamber (4) is accompanied by its gradual modification. Valves (11
and 12) are closed when the required composition of the gas medium
in the container (1) is achieved. After that, the chamber (4) can
be disconnected from the container (1), or it can remain connected
for further atmospheric modification, as needed.
[0035] As an example, let us consider the device as applied to
shipping green bananas in the container. In this case, to prevent
early ripening and spoilage of bananas, in addition to a reduced
temperature (about 14.degree. C.), it is necessary to maintain the
gas medium in the container with reduced oxygen content (relative
to ambient air)--about 2-4%, and increased carbon dioxide content
(relative to ambient air)--about 4-7%. However, during storage, the
bananas absorb oxygen and release carbon dioxide, which leads to
the reduction of the oxygen content (which gets lower than the
normal value) and to the increase of the carbon dioxide
concentration (which gets higher than the normal value) in the
container.
[0036] To maintain the required composition of the gas medium in
the container, the gas-permeable membrane (6) of the chamber (4) is
characterized by a ratio of permeability values of carbon dioxide
and oxygen of about "4", which means that
V(CO.sub.2)/V(O.sub.2).apprxeq.4,
[0037] Taking into account the ratio of concentrations of carbon
dioxide in the container and in ambient air (which, in the latter
case, constitutes approximately 0.03% for carbon dioxide and
approximately 21% for oxygen) based upon the above-described gas
exchange in the chamber, the concentration of carbon dioxide needs
to be reduced, while the oxygen concentration needs to be
increased. Furthermore, gas of modified composition from the
chamber (4) passes from the chamber to the container (1). This
preconditions the compensation of modification of the gas medium
composition in the container that is caused by banana
respiration.
[0038] The absolute permeability value of the membrane (6) material
can be, for example, about 1.12*10.sup.6 cc/100 sq.ins.atm-24 hrs
for carbon dioxide. For oxygen, this value can be about
2.8*10.sup.5 cc/100 sq.ins.atm-24 hrs.
[0039] The indicated characteristics of the membrane (6) material
allow the system to quickly achieve the required concentrations of
oxygen and carbon dioxide in the container (1). It is possible to
use other materials for the membrane, with the same ratio of
permeability values, but with smaller absolute values of this
parameter, which should be compensated for by an increase of the
operating surface area of the membrane.
[0040] The device described above can serve several containers
concurrently.
[0041] For this purpose, the chamber (4) should be equipped with
the appropriate number of input and output channels.
[0042] Additionally, to enhance the entire gas exchange process,
chargers (14 and 15) can be introduced into the chamber (4) (see
FIG. 3), or into the channels for uptake and return (not shown in
FIG. 1). These chargers would ensure the required velocity of the
flow in the chamber. It is possible to use additional chargers if
several containers are connected to the chamber; however, they can
be used only when the container is serviced.
[0043] The rate of gas medium modification in the chamber depends
upon the volume of the chamber, surface area and permeability of
the membrane (6), and the flow rate into and out of the container.
Velocity of flow through the chamber is regulated depending upon
the velocity of the gas exchange and upon the required rate for
substitution of the gas medium in the container (1).
[0044] Control of the gas composition of the atmosphere inside the
container (1) can require an additional gas, for example, ethylene.
In this case (see FIG. 3), an additional input with a connecting
pipe (26) is executed, intended for feeding in gas from an external
gas storage device or from a gas generator.
[0045] In another example of the device (see FIG. 4), the gas
exchange chamber is a section (16) that is connected to the
container (1) from the side of the connecting pipes (7 and 9). The
gas-permeable membrane (6) is installed in the section (16), and is
protected by the wall (17). The membrane has orifices (18) intended
for ensuring contact of the membrane's surface with ambient air.
Channels for uptake of the gas medium from the container and for
the return of the modified gas medium are executed as connection
pipes (19 and 20) of the section (16), correspondingly.
[0046] The section (16) is connected to the container to ensure a
hermetically sealed connection of pipes of the container, to the
connecting pipes (19 and 20) of the section. The device functions
in a manner similar to that of the device presented in FIG. 1, and
described above.
[0047] Also, the device described here can be a separate section
(21) of the container (1), as shown in FIG. 5. In this case, the
section (21), constituting a gas exchange chamber, appears, for
example, in the form of an enclosure constituting a separate part
of the container. The section (21) is connected with the cargo part
of the container via channels in the form of orifices (22 and 23),
blocked by controlled shutters or valves (24 and 25),
correspondingly.
* * * * *