Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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CA 02620798 2008-02-11
A SYSTEM AND APPARATUS FOR THE PRESERVATION AND
TRANSPORTATION OF PRODUCTS INCLUDING LIVE AQUATIC SPECIES
FIELD OF THE INVENTION
The invention relates to a system for transporting products including live
aquatic animals. In particular, the invention relates to a micro-environment
for live
aquatic animals, which can be monitored and controlled locally and remotely.
More
particularly, the invention relates to an apparatus, a system and a method
which
provide the living conditions required to sustain products and live aquatic
animals
in transportation over long distances. The system of the present invention may
be
practical and utilized in apparatus in the form of a trailer, railway car or
similar
vehicle adapted to accommodate the system enclosed herein.
BACKGROUND OF THE INVENTION
Aquatic animals such as, for example, crustaceans are an important food
source (seafood). Crustaceans must typically be kept alive until just before
they are
to be eaten. This has created a need for efficiently transporting live
seafood, as well
as a simple and efficient means for keeping the seafood alive for long periods
of
time.
When preservation of live seafood is intended for only a matter of hours, a
typical means of transportation known in the art includes boxes or crates
filled with
ice. However, when using the above means of transportation and when seafood is
to be transported a longer distance it has been necessary to transport the
seafood
by air. Airfreight has been used to transport seafood, as well as fresh
produce and
other organic food. However, there are several disadvantages associated with
air-
freighted food. In particular, the cost of packaging, including gel packs to
keep the
product cool, is expensive, logistics and handling are complex, since the food
has
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CA 02620798 2008-02-11
to be loaded on a truck, airlifted to the desired destination, and then
unloaded onto
a truck to be delivered to the purchaser, which results in operating costs
that are
prohibitively expensive. In addition, air transport is not, at the present
time,
environmentally friendly due to the amount of packaging used and the amount of
fuel necessary to transport relatively low volumes of food. In addition, the
cost of
carbon emissions may result, in the near future, in a reduction of food which
is air-
transported.
As an alternative to air-freight, ground and/or sea transportation systems for
seafood are also known in the art and usually consist of containers filled
with water
or seawater. The live aquatic animals, which may be transported in such
containers,
include mollusks, crustaceans, and fishes. The transportation of aquatic
animals
over long distances posses a significant challenge since, when the animals
have
been contained in the water for a long period of time, the water will be
contaminated
by their body wastes and oxygen in the water will be decreased. Accordingly,
the
mortality rates are very high.
The problem of transporting live aquatic animals and the context in which this
problem was considered are discussed below. US Patent Application No.
2007/0245971 to Rayner describes a bulk produce transport container including
a
tank capable of supporting a wet environment. The system described by Rayner
primarily uses water as an environment for the live aquatic animals. In
addition, in
the system described by Rayner loading of the product is done through a
manhole
at the top of the tanktainer or in tanks of water.
European Patent No. 72,334 to Martin discloses a process for keeping alive
aquatic animals, such as crustaceans, during transport thereof, in which the
animals
are placed and maintained in a water-tight space.
U.S. Patent No. 3,727,579 to Lee discloses a system and method for
preservation and transportation of lobsters, wherein temperature-conditioned
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aerated salt water is continuously sprayed upon the lobster in a container
from the
time it is caught until it is finally sold.
U.S. Patent No. 3,192,899 to Lucey et at. discloses a somewhat similar
development to Lee's invention, viz a unit for storage of live shellfish, in
particular
crawfish and lobsters, comprising a plurality of trays vertically disposed one
upon
another, each tray having at least one perforation therein, the uppermost tray
being
provided with a sea-water feeding device. The unit may be provided with a
means
for recirculating the water, and refrigeration means to cool directly the
water or the
air.
Japanese Patent Application No. 2004242620 to Yamamoto et at.,
International Patent Application PCT/N02002/328 to Lyngstad, and French Patent
Application No. 2,550,917 to Jean-Francois Toulouse are representative of
applications and/or patents discussing vehicle-mounted water tanks for fishes
for
storing water and having at least one feed pipe and at least one discharge
pipe for
discharging water, and a pumping means for circulating and flowing water. In
addition, U.S. Patents Nos. 5,177,777, 5,309,868, and 5,572,952 to Niino,
Tomiyama and Manonne, respectively, disclose putting the live fish into a
hibernation-like state by cooling the fish to a temperature within a
temperature range
which provides conservation of the fish without being harmful to the fish. In
many of
the above-identified prior art documents the product is immersed in water
thereby
limiting the payload due to the large volume of water that is required.
The invention was developed in recognition of the need for a more efficient
transportation system for live aquatic animals over long distances.
SUMMARY OF THE INVENTION
As used herein the term "seafood" is intended to refer not only to edible
marine fish and shellfish taxonomically classified but also to aquatic
animals,
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3
including inter alia, "fishery products" such as, for example, saltwater fish,
freshwater fish, Crustacea, Mollusca, and Reptilia.
As used herein the term "product" refers mainly to seafood, but can also refer
to produce and/or other organic food as well as plant, or any matter that
requires
preservation.
As used herein the term "water" is intended to comprise freshwater,
seawater, synthetic seawater, plant water, distilled water, or mixtures
thereof.
As used herein the term "tray" is intended to comprise totes, boxes, tubs or
other devices used to contain or hold the product during transport.
An object of the present invention is, thus, to provide a method and system
for transporting live aquatic animals, in particular, seafood, over long
distances.
In accordance with an aspect of the present invention, there is provided a
system for transporting a product, such as, for example live aquatic animals,
in
particular seafood, preferably, but not limited to, shellfish/fish, over long
distances,
comprising a container; one or more than one tray for containing the product;
a
means for spraying liquid into the container and onto the tray for preserving
the
product and permitting the sprayed liquid to drain from the container; a means
for
collecting the drained liquid from the container and returning the liquid to
the means
for spraying; a means for filtering the drained liquid before returning the
liquid to the
means for spraying, the filter means comprising a liquid treatment system and
filtration units.
The temperature inside the container is, preferably, maintained constant with
a view to preserving the product. The container may be provided with an
insulated
layer and/or a heat exchanger mounted on each side of the container.
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The container may include one or more than one drain in the bottom thereof
and one or more than one collecting receptacle, preferably, mounted below the
container. The collecting receptacle may also be mounted on the sides or on
top of
the container in which instance any other known drain and/or a means for
collecting/pumping the liquid from the container in the receptacle may be
used.
In accordance with another aspect of the present invention, there is provided
a self-contained preservation system for transporting a product comprising: a
trailer
vehicle comprising a trailer chassis having front and rear end portions, a
plurality of
wheel supports attached to the trailer chassis, a ground engaging wheel
rotatably
mounted to each of the wheel supports chassis; the trailer chassis comprising
an
elongated platform having four side walls projecting upward from said platform
and
an elongated top frame member extending between said side walls to define an
enclosed space, wherein the space is partitioned into a product storage
compartment/area and a mechanical chamber/room; one or more than one tray; a
means for spraying liquid into the product storage compartment and onto the
tray
for preserving the product and permitting the sprayed liquid to drain from the
container; a means for collecting the drained liquid and returning the liquid
to the
means for spraying; a means for filtering the drained liquid before returning
the liquid
to the means for spraying, the filter means comprising a liquid treatment
system and
filtration units. Preferably the liquid is water.
In the operation of the apparatus and the system of the present invention it
is contemplated that when refrigerated products which co not develop waste are
transported use of at least all the components of the water and filtration
system may
be selectively discarded as the operator deems appropriate for effective
utilization
of the system.
The product may be contained in a plurality of trays which may be placed on
pallets for easy loading/unloading, in vertical arrangement one upon the other
inside
the trailer. The trailer may also comprise a man-door, and mechanical room to
house the system equipment or the equipment may be attached to the trailer.
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The system for transporting live aquatic animals of the invention may also be
referred hereinafter as Live Seafood Transport System (LSTS).
The system may include a controller for monitoring and controlling the entire
system for both automatic and manual operation may. The controller preferably
comprises a Programmable Logic Controller (PLC), which may be pre-programmed
with modes and cycles. The PLC may control the temperature, humidity, pressure
or any other parameter deemed necessary inside the product storage
compartment/area.
The integrated liquid (water) treatment system may comprise two reservoir
tanks, one or more biofilters with bead collectors, a bio-reservoir tank, one
or more
protein skimmers, one or more rotating drum filters, one or more collection
tanks
and/or plumbing with opening/closing valves. The water treatment system may
further include an ultraviolet unit and an ozone unit for treating toxicity of
water
returned to the tank, if required for certain applications. Other components,
known
to a person skilled in the art, may be added to the water treatment system to
ensure
its operation and efficiency.
The product storage compartment/area may be provided with internal walls
and ceiling comprising an insulating layer and/or channels through which air
is
pumped at the desired temperature so as to provide a heat exchanger to control
the
environment in the trailer. Such insulating layer and/or heat exchanger may
also be
provided to the mechanical room. The product storage area may be further
provided
with a means for storing the product, preferably, but not limited to, on trays
placed
on pallets for facilitating loading/unloading of the product. The product
storage area
may be provided with an oxygen control system for controlling a level of
oxygen
within the trailer. The product storage area may include one or more
probes/sensors
for monitoring detecting a water property so as to control operation of the
water
treatment system. The product storage area may be also provided with
probes/sensors for temperature, humidity, pressure, ammonia, carbon dioxide,
pH,
or any other parameter deemed necessary for the preservation of the product.
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Preferably, the probes/sensors provide data to a monitoring system for
monitoring
locally and/or remotely the trailer.
In a preferred embodiment, the product storage area is provided with a spray
and fog system for creating/supporting a wet controlled environment, a
refrigeration
system for controlling the temperature within the product storage area, as
well as
means for draining the water from the product storage area to one or more
collection
receptacles/tanks located, preferably, below the product storage area or
alternatively
a sump and vacuum system for removing water sprayed in the product storage
area
to the collection tank or any other method known to a person skilled in the
art for
collecting and moving the water to the collection tank. In one embodiment of
the
present invention the spray and fog system may also control the temperature
inside
the product storage area by spraying water at the desired temperature.
In another preferred embodiment, the product is formed of aquatic organisms
and the refrigeration unit is adapted to operate in two ranges, one of which
is to
maintain normal living temperature of the organisms and the other of which is
to
maintain the organisms substantially in a dormant state of biostasis. However,
any
other range of operation may be provided based on the properties of the
product
which is hauled with a view to preserving the product or preparing the product
for
loading/unloading.
In accordance with still another aspect of the present invention, there is
provided an apparatus adapted for movability and the transportation of
refrigerated
products such as to minimize their deterioration during transport, the
apparatus
comprising: (a) a non-automotive vehicle adapted for hauling by road, having a
storage compartment structure adapted to be selectively closed against its
outside
environment, wherein dry air is circulated through a heat exchange layer
mounted
on sides of the storage compartment, the heat exchange layer comprises
channels
which are in an airtight relationship with the interior of the storage
compartment, the
dry air being pumped through the channels of the heat exchange layers at a
desired
temperature so as to maintain the temperature inside the storage compartment;
(b)
a system for maintaining products positioned within the storage compartment in
a
refrigerated condition during transportation; (c) the internal confines of the
storage
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compartment apparatus including means for containing the product; (d) a
spraying
assembly structured and positioned for spraying the products positioned within
the
storage compartment product in a manner to facilitate the preservation
thereof; and
(e) means for collecting the unused sprayed liquid and returning it to the
spraying
assembly.
In accordance with still another aspect of the present invention, there is
provided a system for transporting a product in a manner such as to minimize
its
deterioration, the system comprising: a non-automotive vehicle adapted for
hauling
by road, having a container, wherein dry air is circulated through a heat
exchange
layer mounted on sides of the container, the heat exchange layer comprises
channels which are in an airtight relationship with the interior of the
container, the
dry air being pumped through the channels of the heat exchange layer at a
desired
temperature so as to maintain the temperature inside the container; a tray;
means
for spraying liquid into the container and onto the tray to facilitate
preservation of the
product and permit the sprayed liquid to drain from the container; means for
collecting the drained liquid from the container and returning the liquid to
the
spraying means; and means for filtering the drained liquid before returning
the liquid
to the spraying means, the filter means comprising a liquid treatment system
and
filtration units.
In accordance with yet another aspect of the present invention, there is
provided a self-contained preservation system for transporting a product
comprising:
a trailer vehicle comprising a trailer chassis having front and rear end
portions, a
plurality of wheel supports attached to the trailer chassis, a ground engaging
wheel
rotatably mounted to each of the wheel supports chassis; the trailer chassis
comprising an elongated platform having four side walls projecting upward from
the
platform and an elongated top frame member extending between the side walls to
define an enclosed space, wherein the space is partitioned into a product
storage
compartment and a mechanical chamber, wherein dry air is circulated through a
heat exchange layer mounted on sides of the storage compartment, the heat
exchange layer comprises channels which are in an airtight relationship with
the
interior of the storage compartment, the dry air being pumped through the
channels
of the heat exchange layer at a desired temperature so as to maintain the
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temperature inside the storage compartment; one or more than one tray; a means
for spraying liquid into the product storage compartment and onto the tray for
preserving the product and permitting the sprayed liquid to drain from the
container;
a means for collecting the drained liquid and returning the liquid to the
means for
spraying; and a means for filtering the drained liquid before returning the
liquid to the
means for spraying, the filter means comprising a liquid treatment system and
filtration units.
In accordance with still another aspect of the present invention, there is
provided a method for transporting a product in a nonautomotive vehicle
adapted for
hauling by road comprising a refrigeration system operable to maintain and
control
the temperature of the product, the method comprising the steps of: providing
the
non-automotive vehicle comprising a storage compartment for containing the
product spraying a preservative liquid onto the product positioned in the
storage
compartment sufficient to wet the product with the liquid; removing the liquid
from
the storage compartment and thereafter returning the liquid to the storage
compartment; and maintaining a temperature inside the storage compartment such
as to facilitate preservation of the product, wherein dry air is circulated
through a
heat exchange layer mounted on each side of the storage compartment, the heat
exchange layer comprises channels which are in an airtight relationship with
the
interior of the storage compartment, the dry air being pumped through the
channels
of the heat exchange layer at a desired temperature so as to maintain the
temperature inside the storage compartment.
In accordance with still another aspect of the present invention, there is
provided a method for transporting a product in a container comprising the
steps of:
containing the product in a tray; spraying liquid in the container and onto
the tray to
wet the product; removing the liquid from the container and filtering and
recycling the
liquid before returning the liquid to the container; and maintaining a desired
temperature inside the container.
In accordance with a further aspect of the present invention, there is
provided
A method for transporting live aquatic animals in a nonautornotive vehicle
adapted
for hauling by road, the vehicle comprising a storage compartment, the method
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comprising the steps of: arranging the live aquatic animals in position for
spraying
with a preservative in the storage compartment; spraying liquid in a manner to
wet
the live aquatic animals and facilitate removal of the animals waste; removing
at
least a portion of the liquid from the storage compartment and filtering and
recycling
the liquid before returning it to the storage compartment; treating the animal
waste
in the liquid before returning the liquid to the storage compartment; and
maintaining
a temperature inside the storage compartment so as to effectively operate the
method of refrigeration and preservatives wherein dry air is circulated
through a heat
exchange layer mounted on a side of the storage compartment, the heat exchange
layer comprising channels which are in an airtight relationship with the
interior of the
storage compartment, the dry air being pumped through the channels of the heat
exchange layer at a desired temperature so as to maintain the temperature
inside
the storage compartment and prevent drying out of the animals.
In accordance with a further aspect of the present invention, there is
provided
a method for transporting live aquatic animals in the trailer of the present
invention
comprising the steps of: containing the live aquatic animals in the tray;
spraying
liquid in the product storage compartment and onto the tray to wet the live
aquatic
animals and clean away the animals waste; removing the liquid from the product
storage compartment and filtering and recycling the liquid before returning
the liquid
to the product storage compartment; treating the animal waste in the liquid
before
returning the liquid to the product storage compartment; and maintaining a
desired
temperature inside the product storage compartment.
Further scope of applicability of the present invention will become apparent
from the detailed description given hereinafter. However, it should be
understood
that the detailed description and specific examples, while indicating
preferred
embodiments of the invention, are given by way of illustration and should not
be
construed as limiting the invention in any way since various changes and
modifications within the spirit and scope of the invention will become
apparent to
those skilled in the art or science from this detailed description.
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It is to be understood that each specific term includes all technical
equivalents
which operate in a similar manner to accomplish a similar purpose.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments of the present invention will now be described in
conjunction with the following drawings, in which:
Fig. 1 is a top sectional view of the container/trailer of the present
invention;
Fig. 2 is a more detailed top sectional view of the container/trailer and
related
mechanical components attached thereto in accordance with the present
invention;
Fig. 3 is a schematic view of one embodiment of the system for creating and
maintaining a controlled micro-environment in accordance with the present
invention;
Fig. 4 is a flow diagram of the modes and cycles of operation of the PLC in
accordance with the present invention;
Fig. 5 shows an embodiment of a tray used in accordance with the present
invention;
Figs. 6A and 6B are sectional views of the spray reservoir tank of the present
invention;
Fig. 7 is a sectional view of the product storage area of the present
invention;
and
Fig. 8 is a side view of the non-automatic vehicle of the present invention
with
a storage compartment and a mechanical room according to an embodiment of the
present invention.
CA 02620798 2012-03-23
DETAILED DESCRIPTION OF THE INVENTION
The following description is presented to enable a person skilled in the art
or
science to which the present invention pertains to make and use the invention,
and
is provided in the context of a particular application and its requirements.
Various
modifications to the disclosed embodiments will be readily apparent to those
skilled
in the art or science, and the general principles defined herein may be
applied to
other embodiments and applications without departing from the scope of the
invention. Thus, the present invention is not intended to be limited to the
embodiments disclosed, but is to be accorded the widest scope consistent with
the
principles and features disclosed herein.
Referring to Fig. 1 shown is a mobile insulated trailer or container (100). In
one preferred embodiment of the invention, the trailer (100) is provided with
a
product storage area (1) and a mechanical room (2). The product storage area
(1)
is adapted to receive pallets (20) on which a portable storage means,
preferably
trays (21), are vertically disposed one on top of another. The function of the
product
storage area (1) is to provide a space to store the product during transport
along
with the trays and pallets necessary for carrying/holding the product. The
product
storage area (1) is preferably, located in the back of the trailer between the
mechanical room and the loading doors. The mechanical room may be provided on
one side thereof with a man-door (4). The function of the mechanical room (2)
is to
provide a space for the water treatment and refrigeration equipment. The
mechanical room is, preferably, located in the front of the trailer between
the product
storage area and the front of the truck.
Loading/unloading doors (5, 6) are provided, preferably at the back of the
trailer for easy access to the product storage area. The loading/unloading
operation
may be performed by placing the portable trays on a pallet and placing the
pallet
inside the trailer using a forklift.
The refrigeration unit (19) is preferably provided at the front of the
trailer. The
refrigeration unit is connected to the heat exchanger (28) in the product
storage area
via ductwork (27) to provide temperature control of the product storage area.
The
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,
,
refrigeration unit is capable of delivering cool or warm air to the heat
exchanger in
the product storage area by simply diverting the air flow from the evaporator
to the
condenser or vice versa. Dry air delivered to the heat exchanger does not come
in
contact with the product in order to prevent drying out of the animals' gills.
Preferably, the heat exchanger is sized to comprise the entire sidewalls and
ceiling
of the product storage area to provide as constant a temperature as possible
inside
the product storage area. The function of the heat exchanger is to provide a
means
of exchanging the energy in the air with its surroundings in the product
storage area.
The heat exchanger may be made of high-density polyethylene and fiberglass
channels ribbing fastened and sealed to the trailer. The refrigeration system
is also
connected to the chiller barrels (13,14), preferably located in the mechanical
room,
to provide cooling of the water contained in the integrated water treatment
system.
The refrigeration system is split, controlled by the PLC (31), where
preferably the air
temperature in the product storage area is its primary function and the water
temperature in the integrated water Treatment System is its secondary
function.
Referring to Fig. 2 shown is a more detailed top sectional view of the
trailer,
the lower trailer and the product storage area showing all related mechanical
components attached to the trailer. Preferably, the mechanical room, the lower
trailer
area and the product storage area house all components related to the
integrated
water treatment system and refrigeration system. The generator (11), which
supplies all power for the LSTS (100), is located under the trailer. The
collection tank
(3) and collection pump (22) are attached to the underside of the trailer. The
function
of the collection tank (3) is to provide interim storage of water coming from
the
product storage area until the water can be pumped to the integrated water
treatment system in the mechanical room. The tank (3) may be made of high-
density
polyethylene and reinforced for transport, however, any other suitable
material may
be used. The tank (3) is, preferably, equipped with inlet, outlet, vent,
however any
other ports known to one skilled in the art may be provided.
The CO2 exhauster (18) is connected to the collection tank for removing
carbon dioxide. The collection pump supplies water to the RDF (12). Water
leaving
the RDF enters the bio-reservoir (17) and backwash water leaving the RDF
enters
the RDF waste filter (40) to capture solids in the backwashed water waste
stream.
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,
Water in the bio-reservoir is recirculated by the recirculation pump (23)
through the
protein skimmers (8,9), the biofilter (7), the bead collector (30) and the RDF
before
returning to the bio-reservoir. Water flowing through the protein skimmers
generates
foam, which flows to the foam collector (29). Air or oxygen to the biofilter
is provided
by a blower (10). After treatment, water from the bio-reservoir is pumped
through the
ultraviolet filter (32) to the spray reservoir (15) by bio-reservoir pump
(24). Once in
the spray reservoir, the spray pump (25) recirculates the water through
chiller barrels
(13, 14) for cooling. Once the required temperature is met, the spray pump
(25)
transfers the water to the spray system (33) for discharge over the product in
the
trays (21) in the product storage area. Zones valves (34) control the flow to
the
chiller barrels or the spray system. If the temperature in the bio-reservoir
tank is too
cold, the bio-reservoir heater (37) is turned on by the PLC to heat the water.
The integrated water treatment system has a biofilter to remove ammonia and
nitrites, both of which are harmful to live aquatic animals, from the water.
It is vital
that the ammonia and nitrite are removed or converted to harmless nitrate from
the
water otherwise the gills will be burned and the animal will not be able to
respire,
thus death would ensue. To maintain a healthy bacteria culture in the
biofilter during
periods of inactivity, an ammonia injection pump (38) and an ammonia monitor
(39)
are provided as critical integral parts of the system. It is also important to
maintain
the product storage area at a temperature where the live aquatic animals are
in a
dormant state. The function of the biofilter is to reduce or eliminate water
exchanges
by converting harmful ammonia to harmless nitrate thereby allowing for a
closed
loop system. Ammonia (NH4 + and NH3) originates from the brachial excretion
from
the gills of aquatic animals and from the decomposition of organic matter. As
ammonia-N is highly toxic, this is converted to a less toxic form of nitrite
(by
Nitrosomonas sp.) and then to an even less toxic form of nitrate (by
Nitrobacter sp.).
This "nitification" process requires oxygen (aerobic conditions), without
which the
biofilter would not function, and water for cleaning the biofilter media. The
type of
biofilter used is an expandable media filter, which comprises a biofilter tank
filled with
water and plastic biofilter beads and inoculated with nitrosomonas and
nitrobacter
bacteria. However, any other biofilters in any arrangements known to a person
skilled in the art may be used. Preferably, the biofilter tank is connected to
an air or
oxygen supply and also a water supply for cleaning the beads.
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Shown also in Fig. 2 is the fog system. The fog system is a system for
humidification of the product storage area. Preferably, it comprises a fog
reservoir
(16), a fog pump (26) and a fog system (35) to provide humidification of the
product
storage area, which keeps the air moist for the live aquatic animals. The
function of
the fog reservoir (16) is to provide water storage for the fog system and in a
preferred embodiment is made from high-density polyethylene and is equipped
with
inlet, outlet, vent, and ports for probes. The fog reservoir (16) may be
reinforced for
transport. Any other material known to a skilled person may be used as long as
it is
suitable for operation in accordance with the present invention.
Referring now to Fig. 3 shown is a schematic view of the system in
accordance with the present invention. Figure 3 shows the flow path of the
processes occurring in the mechanical room, the product storage area and the
underside of the trailer.
Experiments done with the system of the invention have shown that it is
possible to hold some types of shellfish as long as 30 days before returning
them to
their natural or simulated environment. This has been achieved by maintaining
the
climate in the trailer (100) with a refrigeration system (19) and an
integrated water
treatment system which is complete with a spray system. The refrigeration
system
controls the temperature inside the product storage area. By keeping the
temperature of the animals low there is very little biological activity
occurring. This
reduces the waste products produced by the animals thereby reducing the size
of
the integrated water treatment system. The integrated water treatment system
treats
the waste products in the water thereby allowing a recirculating or a closed
loop
system. The spray/fog system provides the proper humidity and oxygen levels
for
maintaining the life of shellfish in the product storage area.
The LSTS (Live Seafood Transport System) of the present invention can be
operated automatically or manually. The entire process is controlled by the on-
board
PLC for both automatic and manual operation.
Referring now to Fig. 4, the PLC is pre-programmed with modes and cycles.
Each mode is comprised of different cycles. A cycle turns on and controls a
specific
piece of equipment. Automatic operation has five different Modes of operation.
Each
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Mode provides a specific function necessary for sustaining the life of the
animals
and/or maintaining the system in operation during the return trip. Each Mode
has to
be initiated by an operator since it is virtually impossible for the system to
know
when to change Modes.
In automatic operation, the operator selects the different modes as the
transport progresses. The first mode is Start-up Mode (41) followed by, Load
Mode
(42), Transport Mode (43), Climatization Mode (44), and Return Trip Mode (45).
The
selection of modes starts all over again for the next load of product
requiring
transport. There are some tasks such as loading/unloading, filling the system
with
water, maintaining the system, water quality testing, and activation of the
various
modes during transport (so the PLC can monitor and control the function of the
system) which may be manual in nature. These tasks have to be executed in
conjunction with the operation of the system. In addition to automatic
operation, the
entire system can be run manually where the operator would start components or
cycles of the system. During Manual Mode, the operator has to initiate the
various
cycles based on what is required. The PLC would still control the cycle while
operating. Manual operation would normally only be used for initial
commissioning,
maintenance and testing of the system.
Programmable Logic Controllers (PLC) are commonly known in the art, and
are not specific to the invention. Thus, it will be known to one skilled in
the art how
to integrate and operate such a device together with the system and method of
the
present invention.
Referring now to Fig. 5 shown is an exemplary tray used in the present
invention. Portable storage containers may be utilized in the product storage
area.
Preferably, trays (21) having the top, the bottom and all sides slotted or
grated may
be used with a view to allowing water to pass through and preventing any
accumulation of water therein. The trays may also be stackable one on top of
another for transporting the product but also nestable to be compact during
the
return trip.
CA 02620798 2012-03-23
,
Referring now to Figs. 6A and 6B shown is a sectional view of the spray
reservoir (15) and ductwork in the mechanical room (2). An insulating layer
(56)
may be provided to the trailer shell (50). Shown in Fig. 6 A and 6B are
typical supply
(54) and return (55) air which form a heat exchanger (28). Reference numerals
52
and 53 denote return and supply ducts, respectively. The fog reservoir is
shown as
reference numeral 16.
Referring now to Fig. 7 shown is a sectional view of the product storage area
(1). Shown are the trailer shell (50) with insulating layer (56) and a heat
exchanger
(28) with typical supply (54) and return (55) air, and spray system (33), tray
21, and
pallet 20.
It is to be noted that the exemplary embodiment detailed above refers mainly
to a trailer, however, a man skilled in the art should easily appreciate that
the
invention can be readily and easily applied to any container, such as for
example,
containers adapted for transportation by train, airplane, or watercraft with
only minor
changes and adaptations which should be known to a person skilled in the art
or
science pertaining to the subject invention.
In another embodiment of the present invention, the spray system, which
provides wash-down of the waste products, and moisture, and oxygen to the
gills,
may also be adapted to cool/heat the product storage area. In this case the
spray
system uses the same general concept to achieve the design requirements but
reduces the amount of equipment and allows more payload. In accordance with
this
embodiment seawater/water would provide the cooling/heating for the product
area
rather than the air in the ductwork. The refrigeration/heating system would
cool/heat
only the seawater/water and, thus, simplify the system since there would be no
requirement for air cooling/heating. Seawater/water would be sprayed over the
live
shellfish/fish product and drained to the collection tank. From there it would
be
returned to the integrated water treatment system for treatment of the waste
products. After treatment, seawater/water is recycled through the spray
system.
Thus, the seawater/water provides all the cooling/heating versus the air in
the
ductwork and wall panel heat exchanger. The spray system has to operate
continuously or intermittently, however, more frequently than when
cooling/heating
16
CA 02620798 2012-03-23
was done through the air duct system, since it has the additional requirement
of
cooling/heating the product storage area.
Experiment 1
The LSTS comes ready for operation. This means the tanks are filled with
water and the biofilter (7) is activated and ready for transporting live
product. Should
the LSTS be dormant for a period of time and the biofilter (7) not maintained,
filling
of the tanks and reactivating the biofilter (7) is required. This is achieved
by
connecting plant water to the system at its designated connection port and
filling the
biofilter (7), the bio-reservoir (17), the protein skimmers (8,9), spray
reservoir (15)
and fog reservoir (16) tanks and associated plumbing with water by
opening/closing
valves and starting the Biofilter Cycle in Manual Mode to achieve the required
water
volumes in these tanks. Once the tank levels are obtained, the Biofilter Cycle
can
be turned off. The next step is to activate the biofilter by injecting a
quantity of
ammonium chloride in the system to provide feed for the nitrifying bacteria,
which
is necessary for the removal of ammonia and nitrites, and activating the
Blower
Cycle. Depending on how it's done, it can take a period of time to establish a
fully
activated biofilter. Once fully activated, the biofilter requires a constant
supply of
ammonium chloride and oxygen to keep it always ready for operation. Once
complete, the LSTS is ready for Start-up Mode (41).
Start-up Mode (41) has to be initiated approximately 2 hours prior to loading
of product. It starts the generator (11), the Blower Cycle, the RDF Cycle and
the
Biofilter Cycle. Once all systems are started, the PLC (31) will alert the
operator to
change to Load Mode (42). This mode controls all the functions of the
biofilter (7) by
turning on various cycles in the proper sequence. This mode does not take much
time to complete. Start-up Mode (41) will follow Return Trip Mode (45) for
continuous
trip operation.
Once Start-up Mode (41) is completed, the operator has to select Load Mode
(42). Load Mode (42) will maintain all functions of Start-up Mode (41) and now
activate the Refrigeration Cycle. Once activated, the product area is cooled
down
to a set temperature. In addition, water from the spray reservoir is
circulated through
the chiller barrel to lower its temperature to the set-point or if required
the immersion
17
CA 02620798 2012-03-23
heater is turner on to add heat to the water to increase its temperature. The
refrigeration system will alternate between cooling/heating the product
storage area
and cooling the spray reservoir. Water recirculates through the chiller barrel
(13,14)
until it meets the set-point temperature for flushing. When the product area
reaches
its set-point temperature, the PLC (31) will alert the operator that product
can now
be loaded (approximately 2 hours after initiating Start-up Mode (41)) in the
product
storage area (1). Product can be loaded while refrigeration of the water in
the spray
reservoir (15) will continue. Once the product is loaded and the set-point
temperature for both the product storage area (1) and the spray reservoir (15)
is
reached, the system is ready for Transport Mode (43).
Upon completion of Load Mode (42), the operator has to select Transport
Mode (43). Transport Mode (43) will maintain all functions of Load Mode (42).
Once
in Transport Mode (43) the system will confirm the temperature in spray
reservoir
(15) is at the set- point for flushing. It will then initiate a Flush Cycle.
The spray pump
(25) will be activated to pump water from spray reservoir (15) to the product
storage
area (1) by opening and closing zone valves #1, #2 and #3 in proper sequence.
This
will supply the shellfish/fish with clean oxygenated water. The spray water
will
cascade over the product, trays and pallets to the floor below. It will then
drain to
the collection tank (3) located below the trailer via the plumbing connected
bellow
the trailer. After the Flush Cycle is complete, the CO2 exhauster (18) is
turned on to
exhaust gases in the collection tank (3). Next, water is transferred from the
bio-
reservoir (17) to the spray reservoir (15). U.V. disinfection occurs (for
trailers with
this option selected) during the transfer for product requiring sterilization
such as
mussels. Upon transfer, water in the spray reservoir is then recirculated
through the
chiller barrel to cool the treated water to the set-point temperature. After
water is
transferred to the spray reservoir (15), water is transferred from the
collection tank
(3) to the bio-reservoir (17) for treatment. During the transfer, water passes
through
the rotating drum filter (RDF) (12) for filtration. The RDF (12) is a self-
cleaning
rotating filter. Waste and backwash water from the RDF (12) is passed through
the
RDF waste filter in the top compartment of the bio-reservoir (17) where the
waste
is retained and the backwash water is returned to the bio-reservoir (17).
Filtered
water that passes through the RDF (12) is discharged directly to the bio-
reservoir
(17) below. Once the transfer is complete to the bio-reservoir (17), it is
then pumped
18
CA 02620798 2012-03-23
through the protein skimmers (8,9) to the biofilter (7) for treatment. It then
flows by
gravity from the biofilter (7) to the bead collector (30) and then overflows
to the RDF
(12) to return to the bio-reservoir (17) for recirculation. The protein
skimmers (8,9)
remove proteins and organic waste and the biofilter (7) provides digestion of
the
ammonia and nitrites. The bead collector (30), which is a component of the
biofilter
(7), removes any bio-beads that get carried through the system and returns
them to
the biofilter (7). Water from the collection tank (3) is processed for a set
period of
time to remove all the contaminants by continuously recirculating them through
the
protein skimmers (8,9) and the biofilter (7). This process continues for a
preset
period of time or based on the ammonia level in the biofilter (7). Once the
time
period has elapsed, the Flush Cycle can start again and the cycle continues
until the
product is near its destination place. Concurrent with the above modes and
cycles
is a Fog or Humidification Cycle. It is independent from the above cycles and
it
provides for intermittent humidification of the product area.
The next mode of operation is Climatization Mode (44). The operator selects
Climatization Mode (44) 4 hrs before arriving at the destination place.
Climatization
Mode (44) will maintain all functions of the previous modes but it will adjust
the
temperature of the product area to a pre-programmed value (which is dependant
on
the type of product) which is slightly warmer than the transport temperature.
This is
necessary to prepare the product for its destination place where the
temperature is
warmer. Once selected, the PLC (31) will check the temperature of spray
reservoir
(15). If the temperature is below the new set-point, the PLC (31) will
complete
Transport Mode (43) by initiating a flush cycle to empty the spray reservoir
(15) of
the cooler water. Water will then go through the same cycles as Transport Mode
(43)
with the only difference being that the temperature for the product area and
the
spray reservoir will be slightly higher. Climatization Mode (44) will only
activate one
flush cycle at the new set-point temperature. Once one cycle is completed, the
PLC
(31) will warn the operator that the product is ready for unloading. It will
continue to
maintain the temperature in the product storage area (1) until the mode is
changed.
There will be no flushing or fogging occurring in the product area (1) while
the
product is unloaded.
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CA 02620798 2012-03-23
After the product is unloaded, the next mode of operation is Return Trip Mode
(45). The operator has to select Return Trip Mode (45) after the product is
unloaded.
This mode automatically shuts down the Refrigeration Cycle since it is no
longer
required and will turn off equipment not used during the return trip. It will
maintain
the blower (10) on intermittent operation to provide enough oxygen for the
biofilter
(7). It will turn on the ammonia monitor (39) and ammonia injection pump (38)
(for
systems equipped with an ammonia monitor (39) and ammonia injection pump (38)
otherwise manual ammonia addition is required) intermittently for injection of
ammonium chloride to provide food for the nitrifying bacteria thus maintaining
a fully
activated biofilter (7).
INDUSTRIAL APPLICABILITY
The invention provides a system, particularly, a container/trailer for
transporting product, preferably, live aquatic animals over long distances.
The
system may be used to create and maintain a micro-environment for product such
as, for example, live aquatic animals, which can be monitored and controlled
locally
and remotely. The system of the present invention may be, preferably, adapted
to
a trailer, however, may also be adapted for use with other means of
transportation
such as for example, airplanes, trains, and watercraft.
List of reference numerals:
Product Storage Area (1)
Mechanical Room (2)
Collection Tank (3)
Man-door (4)
Loading/Unloading doors (5,6)
Biofilter (7)
Protein Skimmers (8,9)
Blower (10)
Generator (11)
Rotating Drum Filter (12)
Chiller Barrels (13, 14)
CA 02620798 2012-03-23
Spray Reservoir (15)
Fog Reservoir (16)
Bio-Reservoir (17)
CO2 Exhauster (18)
Refrigeration Unit (19)
Pallets (20)
Trays (21)
Collection Pump (22)
Recirculation Pump (23)
Bio-Reservoir Pump (24)
Spray Pump (25)
Fog Pump (26)
Ductwork (27)
Heat Exchanger (28)
Foam Collector (29)
Bead Collector (30)
PLC & Electrical Panel (31)
Ultra Violet Filter (32)
Spray System (33)
Zone Valves (34)
Fog System (35)
Spray Reservoir Heater (36)
Bio-Reservoir Heater (37)
Ammonia Injection Pump (38)
Ammonia Monitor (39)
RDF Waste Filter (40)
Start-up Mode (41)
Load Mode (42)
Transport Mode (43)
Climatization Mode (44)
Return Trip Mode (45)
LSTS - Trailer (100)
Trailer Wheels (70)
Reservoir (3)
21
CA 02620798 2012-03-23
,
Generator (11)
Fuel Tank (71)
Loading Gear (72)
Man Door (4)
The aforesaid description and drawings presented herein teach in
considerable detail workable embodiments within the broad concept of the
present
invention. However, in order to facilitate comprehension of the invention's
mode of
operation by a person skilled in the art, the list of reference numerals
associated with
each technical feature of the invention is provided herein along with a brief
description of several technical features identified therein. It is
particularly noted that
the description of the technical features as provided hereinbelow should not
be
construed as limiting the invention in any way and that each specific term
includes
all technical equivalents which operate in a similar manner to accomplish a
similar
purpose.
Product Storage Area (1) ¨ The function of this area is to provide a space to
store the product during transport along with the trays and pallets necessary
for
carrying/holding the product. The product storage area is, preferably, located
in the
back of the trailer between the mechanical room and the loading doors.
Mechanical Room (2) - The function of this area is to provide a space for the
water treatment and refrigeration equipment. The mechanical room is,
preferably,
located in the front of the trailer between the product storage area and the
front of
the truck.
Collection Tank (3) ¨ The function of the collection tank is to provide
interim
storage of water coming from the product storage area until the water can be
pumped to the integrated water treatment system in the mechanical room. The
tank
is, in a preferred embodiment, located under the trailer and. It may be made
of high-
density polyethylene and reinforced for transport. Any other material known to
a
skilled person may be used for the construction of the collection tank. It may
be
equipped with inlet, outlet, vent and other ports.
22
CA 02620798 2012-03-23
=
Man-door (4) ¨ The function of the man-door is to provide access to the
equipment room. The man-door may be, for example, located on the passenger
side of the trailer near the back of the equipment room.
Loading/Unloading Doors (5,6)¨The function of the loading doors is provide
access to the product storage area for loading and unloading product.
Biofilter (7) ¨The function of the biofilter is to reduce or eliminate water
exchanges by converting harmful ammonia to harmless nitrate thereby allowing
for
a closed loop system. Ammonia (NH4 + and NH3) originates from the brachial
excretion from the gills of aquatic animals and from the decomposition of
organic
matter. As ammonia-N is highly toxic, this is converted to a less toxic form
of nitrite
(by Nitrosomonas sp.) and then to an even less toxic form of nitrate (by
Nitrobacter
sp.). This "nitification" process requires oxygen (aerobic conditions),
without which
the biofilter would not function, and water for cleaning the biofilter media.
The type
of biofilter used may be, for example, an expandable media filter, which
comprises
a biofilter tank filled with water and plastic biofilter beads and inoculated
with
nitrosomonas and nitrobacter bacteria. Any other type of biofilter known to a
person
skilled in the art may be used. Additionally, the biofilter tank may be
connected to
an air or oxygen supply and also a water supply for cleaning the beads.
Protein Skimmer (8,9) ¨ The function of the protein skimmer is to remove
organic and some inorganic material that is bound to the organic material from
the
water to lessen the load on the biofilter. It does this by using the polarity
of the
protein or organic material. The type of protein skimmer which may be used is
a co-
current venturi skimmer. It consists of a long cylinder with a cone shaped
top. Inlet
and outlet plumbing are connected to the skimmer. A venturi is connected to
the
inlet pipe for introducing air to the water for treatment. At the top of the
skimmer is
a discharge port where foam is discharged from the skimmer.
Blower (10) ¨ The function of the blower or air pump is to provide air or
oxygen to the biofilter necessary in the nitrification process. Any blower
known to
person skilled in the art may be used.
23
CA 02620798 2012-03-23
,
,
Generator (11)¨ The function of the generator is to provide electrical power
for the equipment. Preferably, a 12-kilowatt diesel generator may be used for
supplying the LSTS with electrical energy. The generator may be controlled by
the
PLC thereby supplying electrical power when it is required.
Rotating Drum Filter (RDF) (12) ¨ The function of the RDF is to remove
particles from the water. The RDF may be a self-cleaning rotating drum filter
driven
by an electric motor. Preferably, water enters the inside of the rotating drum
and
flows through a 60-micron screen discharging to the bottom of the container.
Particles larger than the screen size are captured and collect on the screen.
As the
screen rotates the particulars dewater and stick to the screen. As the screen
reaches the top the filtered particles are washed off using a spray system
with
system backwash water. Backwash water and particulars are captured on a trough
located inside and above the drum shaft and are washed out of the system to a
large
filter bag at the top of the bio-reservoir for capture. The debris entering
the bag is
captured while the water returns to the system for reuse. The bottom of the
RDF
container has a discharge port so water drains by gravity out of the RDF.
Chiller Barrel (13,14) - The chiller barrel function is to cool the water in
the
integrated water treatment system. The chiller barrel may have a PVC outer
shell
and a dual core titanium tube evaporator inside. The chiller barrel may be
baffled
to create turbulent flow for better heat exchange and may have inlet and
outlet
connects for refrigerant and water.
Spray Reservoir (15) ¨ The function of the spray reservoir is to provide a
storage volume for both the spraying system. The tanks may be made from high-
density polyethylene and may come equipped with inlet, outlet, vent, and ports
for
probes. The tank may be reinforced for transport.
Fog Reservoir (16) ¨ The function of the fog reservoir is to provide water
storage for the fog system. The tank may be made from high-density
polyethylene
and may be equipped with inlet, outlet, vent, and ports for probes. The tank
may be
reinforced for transport.
24
CA 02620798 2012-03-23
Bio-Reservoir (17) ¨ The function of the bio-reservoir is to provide a water
storage volume for the spray system. The tank may be made from high-density
polyethylene and is equipped with inlet, outlet, vent, and ports for probes.
The tank
may be reinforced for transport.
CO2 Exhauster (18) - The function of the CO2 exhauster is to remove CO2 gas
in the Collection Tank. Any exhauster known to a skilled man in the art may be
used
if suitable for operation in accordance with the present invention.
Refrigeration Unit (19)- The function of the refrigeration unit is to provide
a
means for heating and cooling the air and also a means for cooling the water.
Pallets (20) ¨ The function of the pallet is to stack, hold and carry tray
during
loading, unloading and transporting the product. The pallet may be made from
high
density polyethylene for durability, ease of cleaning, non-corrosive and non-
water
absorbing properties but other types known in the art may also be used.
Tray (21) - The function of the tray is to hold the lobster while in transit.
Typically a
tray is perforated in order for water to flow through and not accumulate but
other
types may be used depending on the application. For example, in other
preferred
embodiment the tray may also be provided with a recess and/or slots so as to
allow
a predetermined amount of water to remain captive therein for the purpose of
transportation of finfish.
Collection Pump (22) ¨The function of the collection pump is to transfer water
from the collection tank to the bio-reservoir. Any pump known to a skilled man
in the
art may be used for the collection pump.
Recirculation Pump (23) - The function of the recirculation pump is to
circulate
water from the bio-reservoir through the protein skimmer, the biofilter, the
bead
collector and the RDF to return to the bio-reservoir. Any pump known to a
skilled
man in the art may be used for the recirculation pump.
CA 02620798 2012-03-23
=
Bio-Reservoir Pump (24) ¨ The function of the bio-reservoir pump is to
transfer the water from the bio-reservoir to the reservoir tank. Any pump
known to
a skilled man in the art may be used for the bio-reservoir pump.
Spray Pump (25) - The function of the spray pump is to transfer the water
from the spray tank to the spray system. Any pump known to a skilled man in
the
art may be used for the spray pump.
Fog Pump (26) - The function of the fog pump is to transfer the water from the
fog reservoir to the fog system. Any pump known to a skilled man in the art
may be
used for the fog pump.
Ductwork (27) - The function of the supply and return ductwork both is to
provide a means for air to circulate between the refrigeration system and the
heat
exchanger. The ductwork should be made from non-corrosive material,
preferably,
high density polyethylene material or similar material.
Heat Exchanger (28) ¨ The function of the heat exchanger is to provide a
means of exchanging the energy in the air with its surroundings in the product
storage area. The heat exchanger, preferably, encompasses the sidewalls and
ceiling area of the product storage area of the trailer. It may be made of
high-density
polyethylene and fiberglass channels ribbing fastened and sealed to the
trailer.
However, any other material may be used as long as its operation and function
are
similar.
Foam Collector (29) ¨ The function of the foam collector is to provide a
container to collect the organic and inorganic material discharged in the foam
from
the protein skimmer. It is a container made from high-density polyethylene, or
any
other suitable material known to a person skilled in the art, with inlet,
outlet and vent
ports.
Bead Collector (30) ¨ The function of the bead collector is to provide a means
of capturing biofilter beads that escape the biofilter and return them to the
biofilter
through the use of an air-lift. The bead collector is a simple device made
from
26
CA 02620798 2012-03-23
,
H.D.P.E. It has an inlet chamber for slowing down the flow followed by a
separating
chamber where a large screen collects the beads in one location. An air-lift
is
located in the middle chamber. The last chamber is the outlet chamber where
the
filtered water collects and leaves the device.
PLC & Electrical Panel (31) ¨ The function of the PLC & Electrical panel is to
provide power to and control of all electrical components necessary for the
integrated water treatment and refrigeration system. The PLC & Electrical
Panel
may include the following: a water resistant PVC electrical Panel, PLC and
display
screen, wires, fuses, breakers, switches, relays, transformers, etc. required
for
operation and connection to all equipment.
Ultra Violet Filter (32) - The function of the ultra violet filter is to
disinfect the
water going to the reservoir tank for all live aquatic animals where it is
required such
as mussels. Any ultra violet filters known to a man skilled in the art may be
used
for the system.
Spray System (33) ¨ The function of the spray system is to provide a means
for dispersing water intermittently over the live aquatic animals held in the
trays in
the product storage area. The spray system may be made of plastic pipe
complete
with fittings, valves and nozzles for dispersing the water into a spray. Any
other
material known to a man skilled in the art may used to manufacture the spray
system.
Zone Valve (34) ¨ The function of the zone valve is to provide a means of
diverting the water discharged by the spray pump to the chiller barrel for
cooling or
to the spray system for dispersing over the product in the trays. Any known
zone
valves may used for the system.
Fog System (35) ¨ The function of the fog system is to provide a means for
dispersing a fine fog intermittently in the product storage area to keep the
humidity
at or near 100% moisture when the spray system is not operating. The fog
system
may be made of plastic pipe complete with fittings, valves and nozzles for
dispersing
27
CA 02620798 2012-03-23
, .
,
the water into a fine fog. Any other material known to a person skilled in the
art may
be used to manufacture the fog system.
Spray Reservoir Heater (36) ¨ The function of the spray reservoir heater is
to heat the water in the event that the water is too cold for discharging in
over the
product. Any immersion type heater or similar heater known to a man skilled in
the
art may be used for the application.
Bio-Reservoir Heater (37) - The function of the bio-reservoir heater is to
heat
the water in the Bio-reservoir if the water is too cold in the biofilter for
digesting
ammonia and nitrites. Any immersion type heater or similar heater known to a
man
skilled in the art may be used for the application.
Ammonia Injection Pump (38) ¨ The function of the ammonia injection pump
is to pump ammonium chloride to the biofilter during periods of inactivity to
keep the
bacteria in the biofilter growing.
Ammonia/Dissolved Oxygen Monitor (39) - The function of the
ammonia/dissolved oxygen monitor is to measure the level of ammonia and
dissolved oxygen in the water and output the data to the PLC. Any
ammonia/dissolved oxygen monitor known in the art may be used for the
application.
RDF Waste Filter (40) ¨ The function of the RDF waste filter is to capture the
solid waste in the RDF backwash line and allow the water to return to the bio-
reservoir.
28
