Note: Descriptions are shown in the official language in which they were submitted.
CA 02919010 2016-01-22
HORTICULTURAL NUTRIENT CONTROL SYSTEM AND
METHOD FOR USING SAME
FIELD OF THE INVENTION
[0001] The present invention relates to the field of horticulture and, in
particular, to
methods and systems for formulating and delivering nutrient solutions to
plants.
BACKGROUND OF THE INVENTION
[0002] Increase in world population, decline in arable land, expanding
environmental
concerns, and the increasing demand for locally-grown food and related
products, have
contributed to the growth of alternative horticultural practices. In this
respect, greenhouse
horticulture has become the fastest growing sector of agriculture, ranging
from
commercial-scale horticulture to urban farming and specialist and hobby
growers. A wide
range of plants are being grown in greenhouses and include produce,
ornamentals, and
medicinal plants, produced at varying scales.
[0003] A variety of agricultural techniques are employed in greenhouse
horticulture
involving growth of plants in soil as well as soilless methods. For example,
hydroponics is
a method of growing plants using mineral nutrient solutions in water, without
soil.
Terrestrial plants may be grown with their roots in the mineral nutrient
solution only, or in
an inert medium, such as perlite or gravel. Certain techniques of hydroponics
do not even
require plant roots to be supported in any type of substrate but merely
require the roots to
be suspended and wetted with atomized nutrient solution, e.g., aeroponics.
In
hydroponics, the plant roots are constantly provided with water, oxygen and
nutrients. The
requirements for these elements vary between plant type and growth stage of
the plant
throughout the growth cycle. The challenge for the grower is to keep up with
the plants'
needs and to avoid damaging plants with excesses or deficiencies of minerals,
extremes
in pH and temperature, or a lack of oxygen.
[0004] Irrespective of the particular technique, the success of greenhouse
horticulture
primarily lies in the control and management of growth conditions, in
particular, the
nutrient solution.
Consideration of the nutritional composition, pH, EC (electrical
conductivity), temperature, oxygen content, etc. of the nutrient solution,
over the various
1
CA 02919010 2016-01-22
stages of a crop's lifecycle for the particular type of plant, must be made.
Controlling these
parameters has been facilitated by various computer technologies and
automation tools.
[0005] Computer-controlled in-line nutrient mixing systems are available that
allow
automated injection of nutrient concentrates directly into water lines (e.g.,
Easy Feed
Systems, Oakland, California). These systems comprise a series of chemical
injectors that
draw nutrient concentrates from concentrate tanks and discharge these
concentrates
directly into the water line for distribution to the plants. Such systems do
not rely on
reservoirs for mixing nutrient solutions and consequently mixed nutrient
compositions
cannot be stored for later use.
[0006] United States Patent Publication No. 2013/0283689 describes a method
and
system for examining a source water to determine its chemical and biochemical
make-up,
and formulating an appropriate nutritional formulation for mixing with the
source water
directly in a hydroponic pond in which the plants are grown. The system is
further
described as capable of controlling oxygen content of the nutrient solution in
the
hydroponic pond, through the use of a controller system. The system allows for
the
nutrient solution to be monitored and controlled in culture where the plants
are grown.
[0007] United States Patent Nos. 7,937,187 and 7,809,475 describe a computer
controlled fertigation system comprising a central processing unit which
receives data
from a sensor for measuring total water consumption by a plant. Based on this
data, the
central processing unit directs the preparation of a nutritional solution by
instructing the
transfer of fertilizers from holding tanks to be delivered to mixing tanks.
The holding tanks
and mixing tanks are situated in a fertigation room and connected through
distribution
lines to where the plants are grown. Such systems are designed for commercial-
scale
operations where space is available to accommodate a fertigation room.
[0008] Systems available to date are designed for large scale commercial
operations
and cannot easily be customized for small scale horticulture that are most
frequently seen
with specialty, for example medicinal, and craft-grown crops. In such cases,
nutrient
solutions are typically prepared, monitored, and distributed by manual methods
such as
hand blending which is cumbersome, work intensive, and can be inaccurate. A
continuing
2
CA 02919010 2016-01-22
need therefore exists for a horticultural nutrient control system that is
adaptable to the
needs of smaller scale operations.
[0009] This background information is provided for the purpose of making known
information believed by the applicant to be of possible relevance to the
present invention.
No admission is necessarily intended, nor should be construed, that any of the
preceding
information constitutes prior art against the present invention.
SUMMARY OF THE INVENTION
[0010] The present invention relates generally to a horticultural nutrient
control system
and method for using same. In accordance with one aspect, the invention
relates to a
horticultural nutrient control system for formulating, storing, and dispensing
a nutrient
solution to one or more horticultural crop, comprising:
a reservoir unit for receiving a nutrient solution, mixing said nutrient
solution, and
dispensing said nutrient solution to a corresponding horticultural crop;
a nutrient delivery assembly fluidly connecting a water source and a plurality
of
nutritional component sources to said reservoir unit, said nutrient delivery
assembly
adapted to controllably deliver said water and nutritional components to said
reservoir
unit;
a controller coupled to said nutrient delivery assembly and adapted to direct
the
delivery of said water and nutritional components to the reservoir unit; and
a storage-control unit for housing at least a central processing unit, said
nutrient
delivery assembly, and said plurality of nutritional component sources,
wherein said
central processing unit is operably coupled to said controller.
[0011] In accordance with another aspect, the invention relates to a
horticultural nutrient
control system for formulating, storing, and dispensing a nutrient solution to
one or more
horticultural crop, comprising:
3
CA 02919010 2016-01-22
a reservoir unit for receiving a nutrient solution, mixing said nutrient
solution, and
dispensing said nutrient solution to a corresponding horticultural crop,
wherein said
reservoir unit comprises:
a vertical cylindrical tank terminating at a cone-shaped bottom outlet;
a plurality of vertical baffles extending from the interior surface of the
reservoir unit;
and
a plurality of fluid eductors positioned along the length of each baffle, said
fluid
eductors adapted to deliver said nutrient solution in combination with air or
oxygen to said
reservoir unit;
a nutrient delivery assembly fluidly connecting a water source and a plurality
of
nutritional component sources to said reservoir unit, said nutrient delivery
assembly
adapted to controllably deliver said water and nutritional components to said
reservoir unit
through said plurality of fluid eductors;
a controller coupled to said nutrient delivery assembly and adapted to direct
the
=
delivery of said water and nutritional components to the reservoir unit; and
a storage-control unit for housing at least a central processing unit, said
nutrient
delivery assembly, and said plurality of nutritional component sources,
wherein said
central processing unit is operably coupled to said controller.
[0012] According to one embodiment, the horticultural nutrient control system
described
herein comprises a nutrient delivery asSembly that comprises:
a water valve associated with said water source, wherein said water valve is
controllably actuated by said controller to regulate the flow of water
entering the process
line of said nutrient delivery assembly;
a reservoir inlet valve fluidly connecting said reservoir unit with an inlet
end of said
process line, wherein said reservoir inlet valve is controllably actuated by
said controller to
regulate the flow of fluid entering said process line from said reservoir
unit;
4
CA 02919010 2016-01-22
a plurality of dosing manifolds fluidly connected to each of said plurality of
nutritional component sources, said plurality of dosing manifolds each being
controllably
actuated by said controller to deliver a calculated dose of each corresponding
nutritional
component to said process line;
a plurality of sensors situated in said process line for measuring pH, oxygen
saturation, electroconductivity, or combinations thereof, said plurality of
sensors in
communication with said central processing unit;
a reservoir outlet valve fluidly connecting said process line to said
reservoir unit at
an outlet end of said process line, wherein fluid controllably enters said
reservoir unit; and
one or more pump and fluid gauge assemblies fluidly connected to said process
line for regulating the flow of fluid through said nutrient delivery assembly.
[0013] In accordance with another aspect, the invention relates to a method
for
automatically formulating, storing, and dispensing a nutrient solution for a
designated
horticultural crop, comprising:
designating a horticultural crop for nutrient delivery;
inputting identifying and/or quantitative information for the designated
horticultural
crop into the central processing unit of the system as defined herein;
controllably dispensing water and nutritional components into said nutrient
delivery
assembly for mixing in said reservoir unit, wherein the controller regulates
the dispensed
amounts of water and nutritional components in accordance with the identifying
and/or
quantitative information;
analyzing data measured by at least one sensor in said nutrient delivery
assembly
and dispensing additional nutritional components as determined to be necessary
for the
designated horticultural crop; and
delivering the formulated nutrient solution to the horticultural crop by an
irrigation
device at a predetermined schedule.
5
CA 02919010 2016-01-22
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] These and other features of the invention will become more apparent in
the
following detailed description in which reference is made to the appended
drawings.
[0015] Figure 1 is a perspective view of a nutrient control system according
to one
embodiment of the present disclosure.
[0016] Figure 2 is a perspective view of the reservoir unit of a nutrient
control system
according to one embodiment of the present disclosure.
[0017] Figure 3 is a top view of the reservoir unit of Figure 2, showing the
interior of the
reservoir unit.
[0018] Figure 4 is a perspective view of the storage unit of a nutrient
control system
according to one embodiment of the present disclosure.
[0019] Figures 5A and 5B are a side section view and a front view,
respectively, of the
storage-control unit of Figure 4.
[0020] Figure 6 is a perspective view of the nutrient control system of Figure
1 showing
the interior of the storage-control unit.
[0021] Figure 7 is a schematic diagram of the nutrient delivery assembly of a
nutrient
control system according to one embodiment of the present disclosure.
[0022] Figure 8 is a schematic diagram of the nutrient control system of
Figure 1 in
operation with an exemplary horticultural operation.
[0023] Figure 9 is a flowchart illustrating the process carried out by the
nutrient control
system of Figure 1, according to an embodiment of the present disclosure.
[0024] Figure 10 is a graph showing the dissolved oxygen content (%DO) of a
formulation during preparation by a standard method (A) and by way of the
nutrient
control system of Figure 1, according to an embodiment of the present
disclosure ( = ).
6
CA 02919010 2016-01-22
DETAILED DESCRIPTION OF THE INVENTION
[0025] A horticultural nutrient control system is disclosed herein that is
particularly suited
for formulating customized small-batch solutions. The nutrient control system
of the
present disclosure is a compact system for automated customizeable
formulation,
storage, and dispensing of nutrient solutions. According to certain
embodiments, the
system is self-contained and generally comprises two components consisting of
a
storage-control unit operationally connected to a reservoir unit. The system
is designed to
accommodate applications requiring custom, small-batch, nutrient solutions at
volumes
less than 5 gallons to volumes of up to 150 gallons at a time, according to
certain
embodiments. According to certain embodiments, the system can be designed to
accommodate nutrient solution at volumes of as low as 10 gallons to volumes of
up to 300
gallons. In further embodiments, the system can be designed to accommodate
nutrient
solutions at volumes of between about 50 gallons to volumes of up to 300
gallons. As will
be understood by those skilled in the art, the system can be tailored for the
preparation of
smaller volumes of nutrient solution by adjusting components of the system
such as the
size capacity of the reservoir unit. The compact nature of the system further
allows for a
smaller footprint than current commercial scale systems, that is particularly
advantageous
to small-scale horticultural operations, for example, specialty and craft
greenhouse or
hydroponic horticultural operations, where space can often be limited. The
compact, self-
contained, design of the system further allows the system to be portable.
[0026] In certain embodiments, the system offers an all-in-one approach to
automatic
preparation, storage, and dispensing of nutrient solutions. The system is
programmable to
automatically prepare multiple formulations customized to the nutrient needs
of a
corresponding crop. Each formulation, according to certain embodiments, is
prepared in
the reservoir unit to mix the customized pre-programmed combination of
nutrient
concentrates, adjust and stabilize the pH of the solution to the required
level, aerate the
nutrient solution and/or supersaturate the nutrient solution with oxygen, and
optionally
adjust the temperature of the solution. The customized nutrient solution can
then be
stored in the reservoir until needed.
7
CA 02919010 2016-01-22
[0027] According to certain embodiments, the system can be programmed to
prepare
multiple, complex, nutrient solution formulations, each of which being custom
blended to
the needs of a particular crop of plants in a multi-zone horticultural
operation. Each
custom nutrient blend may be custom blended in small-batch volumes and
dispensed
from the reservoir unit to the corresponding zone of plants in the
horticultural operation.
Multiple custom nutrient solutions can thus be prepared, stored, and dispensed
to the
desired crop zone, at the grower's discretion. In this way, a horticultural
operation having
multiple zones that each comprise different plant types or stages of plant
development
requiring a uniquely customized nutrient formulation, can be accommodated.
[0028] The reservoir unit of the system, according to certain embodiments, is
configured
to allow nutrient concentrates, water, and pH adjusting chemicals, to be added
in
measured amounts from sources that can be housed in the operatively connected
storage-control unit of the system. The reservoir unit is configured to allow
custom
blending of all components of a nutrient solution to take place in a single
vessel and
stored until needed. The reservoir unit is generally cylindrical in shape with
a coned
bottom outlet. Nutrient concentrates can be added to the reservoir unit
through a nutrient
delivery assembly that fluidly connects the concentrates stored in the storage-
control unit
to the reservoir unit. A plurality of baffles and fluid eductors situated in
the interior of the
reservoir unit allow oxygen to be injected into the nutrient solution
contained therein to
create a "whirlpool" effect, or vortex, whereby the nutrient components can be
thoroughly
mixed in a top to bottom manner into solution, and simultaneously aerated, or
in some
embodiments supersaturated with oxygen, without mechanical mixing. In this
way, the
solution can be completely prepared in the reservoir unit and stored until
ready to use.
Definitions
[0029] Unless defined otherwise, all technical and scientific terms used
herein have the
same meaning as commonly understood by one of ordinary skill in the art to
which this
invention belongs.
[0030] As used herein, the term "about" refers to an approximately +/-10%
variation from
a given value. It is to be understood that such a variation is always included
in any given
value provided herein, whether or not it is specifically referred to.
8
CA 02919010 2016-01-22
[0031] The term "plurality" as used herein means more than one, for example,
two or
more, three or more, four or more, and the like.
[0032] The use of the word "a" or "an" when used herein in conjunction with
the term
"comprising" may mean "one", but it is also consistent with the meaning of
"one or more",
"at least one", and "one or more than one".
[0033] As used herein, the terms "comprising", "having", "including", and
"containing",
and grammatical variations thereof, are inclusive or open-ended and do not
exclude
additional, unrecited elements and/or method steps. The term "consisting
essentially of'
when used herein in connection with an apparatus, system, composition, use or
method,
denotes that additional elements and/or method steps may be present, but that
these
additions do not materially affect the manner in which the recited apparatus,
system
composition, method or use functions. The term "consisting of' when used
herein in
connection with an apparatus, system, composition, use or method, excludes the
presence of additional elements and/or method steps. An apparatus, system
composition,
use or method described herein as comprising certain elements and/or steps may
also, in
certain embodiments consist essentially of those elements and/or steps, and in
other
embodiments consist of those elements and/or steps, whether or not these
embodiments
are specifically referred to.
[0034] The term "fluid" as used herein includes liquids, gases, slurry
solutions, gels,
dispersions, suspensions of powders in an aqueous medium, or otherwise
flowable
materials or materials that are flowable.
[0035] The term "nutrient components" or "nutritional components" used
interchangeably
herein means macro or micro fertilizer components such as, for example and
without
limitation, any vitamins, minerals, organic components, and chemicals that are
needed to
support plant growth. Nutrient components can be in the form of pre-mixed
nutrient
concentrates that may be commercially available. Nutrient components may also
include,
without limitation, pH-adjusting and/or electroconductivity-adjusting
chemicals.
[0036] The term "horticultural crop zone" or "crop zone" of a horticultural
operation as
used herein means a defined area or group of plants in a horticultural
operation that share
9
CA 02919010 2016-01-22
the same nutritional and/or watering needs due to being at the same stage of
development or being of the same plant type, for example.
Horticultural Nutrient Delivery System
[0037] The horticultural nutrient control system, according to embodiments of
the
present disclosure, offers an all-in-one system that is adapted for
formulating, storing, and
dispensing a nutrient solution to one or more horticultural crop. The system
is generally
comprised of two units consisting of a storage-control unit operably connected
to a
reservoir unit. The units are compact and can be made to be portable. In this
way, the
horticultural nutrient control system is adaptable for use in relatively
confined spaces often
found with specialty greenhouse operations.
[0038] Referring to Figure 1, the two main units of a horticultural nutrient
control system
of the present disclosure are shown. The reservoir unit 10 is generally a
vertical
cylindrical mixing tank that is configured for receiving a nutrient solution,
mixing said
nutrient solution, and storing and/or dispensing said nutrient solution to a
corresponding
horticultural crop. The reservoir unit 10 is operably connected to a storage-
control unit 35
within which is typically housed a programmable logic control system (PLC), a
nutrient
delivery assembly, and a plurality of nutritional component sources (not
shown).
[0039] The PLC comprises a central processing unit (CPU) that is coupled with
a
processor memory, wherein the processor memory includes a system software. The
system software includes software encoded instructions that direct the CPU and
coupled
controllers to execute or instantiate the aspects of the horticultural
nutrient delivery system
described herein.
[0040] The reservoir unit 10 (Figure 2) comprises a vertical cylindrical tank
60 having at
least one inlet for receiving nutrient components and terminating at one or
more bottom
drain outlet 65 through which nutrient solution exits. The reservoir unit 10
will typically
have a removable lid 210 at its top end and terminate in a cone-shaped bottom
to allow
for efficient drainage, however, according to alternative embodiments of the
present
disclosure, a flat bottom or a slope bottom is contemplated. According to
embodiments of
the present disclosure, the tank 60 terminates in a cone-shaped bottom outlet
having a
CA 02919010 2016-01-22
cone angle of no less than about 15 , no less than about 20 , no less than
about 25 , no
less than about 30 , no less than about 35 , no less than about 40 , or no
less than about
54 . According to certain embodiments, the cone-shaped bottom outlet has a
cone angle
of less than about 54 . According to other embodiments, the cone-shaped bottom
outlet
has a cone angle of about 54 .
[0041] The tank 60 itself can range in size depending on the desired
volume capacity,
however, for most specialty horticulture operations the desired volume
capacity can range
from a volume of between about 10 to about 300 gallons. According to certain
embodiments, the tank 60 has a tank volume of up to about 150 gallons.
According to
other embodiments, the tank 60 has a tank volume of up to about 300 gallons,
250
gallons, 200 gallons, 150 gallons, 100 gallons, 75 gallons, 60 gallons, 50
gallons, 40
gallons, 30 gallons, 20 gallons, or 10 gallons. To accommodate even smaller
scale
operations, a tank 60 having a volume capacity of less than 5 gallons can be
used.
[0042] The tank 60 is made from standard materials known in the art. For
example,
according to certain embodiments, stainless steel, carbon steel,
polypropylene, or
polyethylene tanks can be used. According to preferred embodiments, the tank
60 is a
stainless steel tank. The tank 60 can further be adapted with tank heating or
cooling
systems known in the art to allow the temperature of the nutrient solution to
be controlled
and/or adjusted to the horticulture crop of interest.
[0043] The reservoir unit 10 of the present disclosure does not require an
agitator in
order to achieve sufficient mixing of the nutrient solution. According to
embodiments of the
present disclosure, the nutrient solution is mixed within the tank 60 of the
reservoir unit 10
without mechanical mixing. In this way, the temperature of the nutrient
solution can be
better controlled, as well the dimensions of the tank 60 design become less
critical in
achieving sufficient mixing. Tanks can thus be sized to be easily portable,
for example
sized to fit through a standard-sized door, and be housed in relatively
confined spaces,
without compromising adequate mixing of the nutrient solution. In this regard,
according to
certain embodiments, the tank 60 can be supported by legs 195 having casters
200 in any
combination of swivel and rigidity in order to achieve the desired transport
movement.
According to certain embodiments, the casters can include a fixed brake. For
example,
11
CA 02919010 2016-01-22
casters 200 with sealed ball bearings can be used for minimal movement force
as well as
smooth operation. According to alternative embodiments, the tank 60 can be
supported
by a stand comprising such casters to facilitate movement.
According to other
embodiments, the tank 60 can be permanently fixed in position by bolt-down
flanges to
securely fix the legs of the tank to the floor for stability when required
(not shown).
[0044] According to certain embodiments of the present disclosure, the tank 60
has a
diameter of between about 1.5' to about 5.5', between about 2.0' to about
4.5', or between
about 2.5' to about 4.0'. According to a preferred embodiment, the tank 60 has
a diameter
of about 2.5'. The height of the tank 60 typically ranges from between about
4.0' to about
12.0', between about 4.5' to about 10', between about 5.0' to about 8.0', or
between about
5.5' to about 7.0'. According to a preferred embodiment, the tank 60 has a
height of
between about 4'5" to about 6'5". According to a further embodiment, the tank
60 has a
height of about 5.5'. According to another embodiment, the tank 60 has a
height of about
6.3'. It is further contemplated that a smaller tank 60 can be used for even
smaller scale
operations. According to such embodiments, the tank 60 can have a diameter of
less
than 12".
Aerated/Oxygenated, Non-Mechanical Mixing ¨ Baffled Reservoir Unit
[0045] As discussed, the reservoir unit 10 of the present disclosure achieves
non-
mechanical mixing. As shown in Figures 2 and 3, the interior of the tank 60 is
configured
with at least two graduating baffles 70 that gradually extend from the
interior surface of the
tank 60. According to certain embodiments of the present disclosure, the tank
60 can
comprise between two to four baffles 70. According to preferred embodiments,
the tank 60
comprises two baffles 70. The baffles 70 extend approximately the full length
of the tank
60, leaving some space at the bottom of the tank 60 to avoid the build-up of
solids and
extending just above the maximum liquid level of the tank 60. The baffles 70
are arranged
approximately equidistant from each other in order to ensure efficient mixing
of the
nutrient solution. Each baffle 70 gradually extends from the interior surface
of the tank 60
to a final width of between about 2.0" to about 5", between about 3.0" to
about 4.5",
between about 3.5' to about 4.0". According to a preferred embodiment, the
baffle has a
final width of about 2.5". According to a further embodiment, the baffle has a
final width of
12
CA 02919010 2016-01-22
about 3.0". In
embodiments designed for even smaller scale operations, it is
contemplated that the baffle can have a final width of less than 1".
[0046] The final width of the baffle 70 will be sufficient to house a
plurality of fluid
eductors 75 which are positioned along the length of each baffle 70 and inject
nutritional
components and/or nutrient solution into the tank 60. The injected fluid
enters the tank 60
in a naturally swirling or whirlpool fluid flow thereby allowing the fluid to
mix as it is injected
into the tank 60. According to certain embodiments, each baffle 70 comprises
between
three and seven fluid eductors 75 along its respective length. In some
embodiments, each
baffle 70 comprises four fluid eductors 75 along its respective length.
According to
preferred embodiments, the fluid eductors are venturi jet eductors, although
it will be
apparent to those skilled in the art that alternative fluid eductors may be
used to achieve
the same effect.
[0047] The direction of the baffles 70, according to certain embodiments, can
be
oriented to inject fluid into the tank 60 in a clockwise direction to create a
clockwise
swirling or whirlpool fluid flow. According to other embodiments, the baffles
70 can be
oriented to inject fluid into the tank 60 in a counter-clockwise direction to
create a counter-
clockwise swirling or whirlpool fluid flow.
[0048] The nutrient solution enters the tank 60 through the fluid eductors 75
and may be
recirculated through the fluid eductors 75 for thorough mixing. In such
embodiments,
nutrient solution is simultaneously aerated as it is injected into the tank 60
and in this way
oxygen is introduced into the nutrient solution. According to further
embodiments, the
fluid eductors 75 can be further adapted to inject oxygen in combination with
the nutrient
solution into the tank 60. In
this way, the nutrient solution can be saturated or
supersaturated with oxygen if desired. According to such embodiments, the
plurality of
fluid eductors 75 is fluidly connected to an oxygen source.
[0049] The oxygen levels of water initially entering the system from a water
source will
not necessarily be consistent and will decline rapidly over time. As such it
has proven
difficult with prior art methods to consistently control oxygen levels. By
introducing oxygen
into the nutrient solution via the fluid eductors 75, as the solution enters
the reservoir unit
13
CA 02919010 2016-01-22
10, the oxygen levels in the solution can be controllably increased so as to
provide a more
consistent nutrient solution.
[0050] The reservoir unit 10 is operably connected to a storage-control unit
35.
Referring to Figures 4, 5A, 5B, and 6, the storage-control unit 35 houses and
comprises
a power supply, programmable logic controller (PLC) with central processing
unit (CPU)
40 having a data storage device and an exterior-facing interactive display 85.
In addition
to housing the PLC/CPU 40, the storage-control unit 35 houses a nutrient
delivery
assembly 20 which is operably connected to the PLC/CPU 40 and further fluidly
connected to a plurality of nutritional component sources 25 also housed
within the
storage-control unit 35. In this way, the compactness and portability of the
nutrient control
system 1 is maintained. As with the reservoir unit 10, the storage-control
unit 35 can also
be supported on casters 200 in any combination of swivel and rigidity in order
to achieve
the desired transport movement. According to certain embodiments, the casters
can
include a fixed brake. For example, casters 200 with sealed ball bearings can
be used for
minimal movement force as well as smooth operation.
Custom Nutrient Formulation ¨ Nutrient Delivery Assembly
[0051] As shown in Figure 6, the nutrient delivery assembly 20 is housed
within the
storage-control unit 35 and fluidly connects the reservoir unit 10 to a water
source 15 and
a plurality of nutritional component sources 25 that are controllably
dispensed in
calculated amounts to create a preprogrammed nutrient solution formulated for
a targeted
horticultural crop. The nutrient delivery assembly 20 is coupled to the
controller in
communication with the CPU to direct the preprogrammed dispensing of the water
and
nutritional components.
[0052] It will be appreciated by those skilled in the art that the nutrient
delivery assembly
20 can be configured in a variety of arrangements for which one exemplary
embodiment is
described herein. Referring to Figures 6 and 7, the nutrient delivery assembly
20
comprises a process line 95 fluidly connecting the water source 15,
nutritional component
sources 25, and the reservoir unit 10. As illustrated by the exemplary
embodiment shown
in Figure 7, the nutrient delivery assembly 20 forms a feedback loop with the
reservoir
unit 10 to allow the nutrient solution to be recirculated through the nutrient
delivery
14
CA 02919010 2016-01-22
assembly 20 whereby nutritional parameters can be monitored and adjusted, and
thorough mixing can be achieved prior to storage and/or dispensing to the
target
horticultural crop.
[0053] According to embodiments of the present disclosure, the nutrient
delivery
assembly 20 comprises a water valve 90 associated with the water source 15 and
controllably actuated by a controller to regulate the flow of water entering
the process line
95. According to certain embodiments, the nutrient delivery assembly 20
comprises a
flow meter, such as a magnetic inductive flow meter, whereby water flow is
analyzed to
determine and control the volume of water entering the process line 95.
Nutrient solution
from the reservoir unit 10 can also be controllably fed into the nutrient
delivery assembly
via a reservoir inlet valve 100 connected to the reservoir unit 10 at a bottom
outlet 65.
According to certain embodiments, the reservoir inlet valve 100 is located
downstream
from the water valve 90 and under the control of a controller. Downstream of
both the
water valve 90 and reservoir inlet valve 100 is situated a plurality of dosing
manifolds 105
15 fluidly connected to each of the plurality of nutritional component
sources 25 and
controllably actuated by a controller to deliver a calculated dose of each of
the
corresponding nutritional components into the process line 95. According to
certain
embodiments, the nutritional component sources are each equipped with a
respective
dosing pump 145 to allow for controlled delivery of a nutritional component to
the
20 respective dosing manifold 105. The dosing manifolds 105 are further
equipped, in
certain embodiments, with one-way check valves which allow the nutrient
components to
flow into the process line 95 without back pressure contamination.
[0054] Nutrient components for horticultural crops are commercially available
in a
variety of well-known forms and compositions. For example, without limitation,
ready-to-
use concentrated nutrient components such as FloraGro, FloraMicro, FloraBloom,
Flora
Blend, Flora Nectar and Floraliscious Plus (General Hydroponics) and Jungle
Juice, pH
Perfect, and Nirvana (Advanced Nutrients) are readily available and can be
used in the
system described herein. According to certain embodiments, the nutrient
delivery
assembly 20 can be configured to accommodate up to 18 nutrient components each
individually dispensed via the dosing manifold 105. According to preferred
embodiments,
CA 02919010 2016-01-22
the nutrient delivery assembly 20 can be configured to individually dispense
up to 18
nutrient components into the process line 95.
[0055] The feedback loop configuration of the system of the present disclosure
facilitates any number of composition parameters of a nutrient solution to be
monitored
and adjusted to the desired level before application to a horticultural crop.
In this way, it
can be assured that a nutrient solution is suitable before application.
According to certain
embodiments, the pH, oxygen saturation, electroconductivity, or combinations
thereof, of
the nutrient solution can be monitored and adjusted in the process line 95. In
such
embodiments, the process line 95 comprises a plurality of sensors 45, 50
capable of
monitoring such parameters that are in communication with the CPU to
controllably
dispense nutritional components suitable for adjusting such parameters.
According to a
certain embodiment, the process line 95 can comprise an acid and base manifold
controllably actuated by a controller to deliver a calculated dose of acid
and/or base into
the process line 95 until the desired pH is achieved. According to certain
embodiments,
the process line 95 is orientated to slope so as to direct fluid into the
section of the
process line 95 in which the one or more sensors are located even between
operations so
as to maintain moisture levels for sensor maintenance.
[0056] A reservoir outlet valve 160 situated at an outlet end of the process
line 95
provides for the controllable flow of nutrient solution into the reservoir
unit 10, via the fluid
eductors, where the nutrient solution is mixed, stored, recirculated through
the nutrient
delivery assembly 20 or dispensed to the targeted horticultural crop. One or
more pump
155 and fluid gauge 120 assemblies fluidly connected to the process line
ensures
regulated flow of fluid through the nutrient delivery assembly 20. According
to certain
embodiments of the present disclosure, fluid is delivered through said
nutrient delivery
assembly 20 at a flow rate of between about 50 to about 100 litres/minute.
According to
other embodiments, the flow rate of fluid is between about 60 to about 80
litres/minute.
According to preferred embodiments, the flow rate of fluid is between about 67
to about 71
litres/minute. According to certain embodiments, the fluid pressure within the
nutrient
delivery assembly 20 is maintained at a pressure of between about 3 to about
10 psi,
between about 3 to about 7 psi, or between about 5 to about 8 psi.
16
CA 02919010 2016-01-22
Multi-Zone Delivery- Irrigation Assembly
[0057] Once formulation of a nutrient solution is completed in the nutrient
delivery
assembly 20 / reservoir unit 10, the nutrient solution can be stored in the
reservoir unit 10
or alternative storage container for later use, or directly applied to a
target horticulture
crop for which the nutrient solution was customized for.
[0058] Referring to Figure 7, the reservoir unit 10 is fluidly connected to
one or more
irrigation device (not shown) through an irrigation assembly 80 that allows
for controllable
delivery of the nutrient solution from the reservoir unit 10 to one or more
zones in a
horticultural operation. The horticultural nutrient delivery system of the
present disclosure
can be adapted for use with commercially available irrigation devices that
include, for
example and without limitation, drip emitters, and various sprinkler systems.
According to
embodiments of the present disclosure, the irrigation assembly 80 comprises an
irrigation
line 220 that fluidly connects the reservoir unit 10, at a bottom outlet 65,
to one or more
irrigation device in each zone of the operation. The irrigation assembly 80
further
comprises one or more pump 115 and pressure gauge 120 and/or regulator 125,
under
the control of a controller, to control the flow of nutrient solution through
the irrigation line
220 whereby the nutrient solution is directed to one or more zones by way of
corresponding irrigation valves 170, 175, 180, or is drained as waste 165.
Each irrigation
valve 165, 170, 175, 180 is controllably actuated by a controller in
communication with the
CPU to direct and regulate the delivery of the nutrient solution to the
targeted zone.
According to certain embodiments, the irrigation assembly 80 further comprises
an inline
filter 130 to prevent particulates from clogging the irrigation assembly 80.
According to
preferred embodiments, the drain valve 165 will by-pass (not shown) the inline
filter 130
so as to avoid unnecessary clogging of the filter.
[0059] According to embodiments of the present disclosure, the horticultural
nutrient
control system can be preprogrammed with preset fluid delivery programs
allowing the
operator to select the frequency of delivery, time of delivery, the targeted
crop zone for
delivery, the formulation of the nutrient solution to be delivered, the
conditions (e.g., pH,
temperature, salinity) of the nutrient solution for delivery, and the amount
to be delivered,
for example. As well, according to certain embodiments, the horticultural
nutrient control
17
CA 02919010 2016-01-22
system can further include one or more soil moisture sensors that are placed
in each
horticultural zone and which communicate with the CPU to automatically
activate the
nutrient control system based on the specific needs of the horticultural zone
as
determined by the soil moisture content. Data from the one or more sensors is
analyzed
by the CPU to determine activation of the horticultural nutrient control
system to formulate
and deliver a customized nutrient solution. In this way, the horticultural
nutrient control
system of the present disclosure can be automated.
[0060] The number of crop zones that can be accommodated by the horticultural
nutrient delivery system of the present disclosure will depend on the volume
of nutrient
solution required and the volume capacity of the reservoir unit. According to
certain
embodiments, the horticultural nutrient delivery system of the present
disclosure can be
configured to deliver nutrient solution to up to 15 crop zones. According to
further
embodiments, the horticultural nutrient delivery system can be configured to
deliver
nutrient solution to up to 12 crop zones. According to other embodiments, the
horticultural
nutrient delivery system can be configured to deliver nutrient solution to up
to 8 crop
zones. According to further embodiments, the horticultural nutrient delivery
system can be
configured to deliver nutrient solution to up to 5 crop zones.
Method
[0061] In exemplary operation, as illustrated in Figure 9, the operator
selects the
desired fluid delivery mode suitable for the targeted horticultural crop zone
or zones in an
operation. For example, according to embodiments of the present disclosure,
the nutrient
delivery system can be preprogrammed for one-time delivery, regular scheduled
delivery,
or automatic delivery based on soil moisture levels. In such embodiments, the
CPU will
be preprogrammed with instructions for nutrient solution delivery including,
without
limitation, nutrient solution composition/formulation, delivery schedule,
frequency and
duration, soil moisture levels for automatic delivery, delivery volume, crop
zone, pH,
temperature, and salinity, for example. According to embodiments in which
nutrient
delivery is automatically activated based on soil moisture data, at least one
soil moisture
sensor is positioned in the designated horticultural crop.
18
CA 02919010 2016-01-22
[0062] The selected delivery program will be activated based on the
identifying and/or
quantitative information input by the operator into the CPU, for a designated
horticultural
crop. According to an exemplary embodiment, and referring to Figure 7, the
system will
commence by energizing the water valve 90, pump 155, and reservoir inlet valve
100 to
pressurize the process line 95 to the programmed pressure and flow rate.
According to a
certain embodiment, the process line 95 will be pressurized to about 3-7psi
and a flow
rate of 67-71 litres/minute.
[0063] The required dosing pumps will then be energized to dispense the
programmed
amounts of selected nutritional components via dosing manifolds 105 into the
process line
95. A magnetic inductive flow meter monitors the amount of water passing
through the
process line 95 until the desired volume has accumulated in the process line
95 to trigger
de-energization of the water valve 90. The reservoir outlet valve 110 is then
energized
resulting in circulation of the nutrient solution through the reservoir unit
10 for a calculated
period of time ensuring a thoroughly mixed solution. According to embodiments
of the
present disclosure, oxygen saturation, pH, salinity, and other parameters
measurable by
sensors located in the nutrient delivery assembly 20, can be monitored and
adjusted
during circulation of the nutrient solution.
[0064] According to certain embodiments, for example, the pH of the nutrient
solution is
monitored by a pH sensor 45 located in the nutrient delivery assembly 20. pH
data is
relayed to the CPU for analysis and based on the data collected, the acid/base
manifold
135, 160 will be activated to dispense a calculated volume of acid and/or base
to adjust
the pH of the nutrient solution to the desired level for the particular
programmed nutrient
solution formulation. Adjustment and stabilization of the pH of the nutrient
solution to the
desired level can, therefore, be achieved quickly and automatically with
little risk of
overshooting which typically occurs using manual methods.
[0065] Once the desired parameters have been achieved, the pump 155, reservoir
inlet
valve 100, and reservoir outlet valve 110 are de-energized. The irrigation
pump 115 and
the zone valve 170, 175, 180 for the targeted zone is then energized and the
nutrient
solution is allowed to flow into the irrigation line 220 for dispensing to the
targeted zone in
accordance with the programmed schedule. According to certain embodiments, the
19
CA 02919010 2016-01-22
nutrient solution is then dispensed via pressure regulated irrigation pump 115
through the
irrigation line 220 at a flow rate of 0-82 litres/minute.
[0066] As illustrated in Figure 8, the nutrient delivery system 10 of the
present
disclosure can be configured to deliver specific nutrient solutions to a
horticultural
operation comprising multiple crop zones of differing development stages and
plant types
in a customized manner.
[0067] To gain a better understanding of the invention described herein, the
following
examples are set forth. It will be understood that these examples are intended
to describe
illustrative embodiments of the invention and are not intended to limit the
scope of the
invention in any way.
EXAMPLES
EXAMPLE 1: Comparison of Dissolved Oxygen Content (%DO)
[0068] Dissolved oxygen is vital for the health and strength of the root
system of a plant
as well as being necessary for nutrient uptake. Typical manual methods for
nutrient
solution formulation utilize aeration methods such as a submerged air stone
connected to
an air pump, and manual agitation of the solution, in order to introduce and
maintain
dissolved oxygen levels in the nutrient solution at the time of delivery to
the plants.
[0069] The dissolved oxygen content of a formulation prepared by such a
standard
manual method compared to the same formulation prepared by the nutrient
control
system of the present invention was investigated.
Method:
Standard Manual Method
[0070] 135 gallons of a nutrient formulation (herein referred to as
formulation "A") was
prepared in a 150 gallon livestock feed-trough style reservoir. Water was
delivered from a
400 gallon water holding tank using a 1 hp pump. Temperature ( C), Dissolved
Oxygen(%), Conductivity(ppm), and pH was measured throughout the process of
preparation. Formulation A was then manually measured and combined with the
water in
CA 02919010 2016-01-22
the reservoir and mixed within the reservoir using a 1/3 hp pump which was
manually
moved around the reservoir.
[0071] At the completion of preparation, the pH of the nutrient solution was
manually
adjusted to a desired pH of about 6.5 0.3. Once the pH was stabilized,
mixing was
continued for 20 minutes before nutrient solution was dispensed by scooping
solution from
the reservoir using a 5 gallon pail, a typical method of delivery to potted
plants. The
dissolved oxygen content of the dispensed nutrient solution was measured
(Oakton
D0600 Dissolved Oxygen/Temperature Meter) immediately after dispensation into
the pail
and at 1, 2, 3 and 4 minutes after dispensation.
Nutrient Control System
[0072] 135 gallons of Formulation A was auto-formulated in the nutrient
control system
of the instant application. Water from the same 400 gallon water source used
in the
standard manual method was utilized in the control system. Temperature( C),
Dissolved
Oxygen(%), Conductivity(ppm), and pH was measured throughout the process of
preparation. The pH of the nutrient solution was auto-adjusted until
stabilized at a pH of
about 6.5 0.3. Once the pH was stabilized, nutrient solution was dispensed
from the
reservoir of the nutrient control system via a 50 foot, 1/2" hose.
[0073] Dissolved oxygen was measured immediately after dispensation into a
2000 mL
measuring cup, and at 1, 2, 3 and 4 minutes after dispensation.
Results:
[0074] Measurements were taken of the source water in the source water
reservoir and
of the source water during filling of either the standard or system mixing
reservoir.
Measurements were also taken during formulation, mixing of the formulation,
immediately
at dispensation, and at 1, 2, 3, and 4 minutes after dispensation of the
nutrient solution.
21
CA 02919010 2016-01-22
Table 1: Nutrient Solution Measurements During Preparation
Sample pH Conductivity Temperature Dissolved Preparation
(PPm) Oxygen Time
( C)
(%DO)
(minutes)
Source Water 6.7 55 20.6 98.6 N/A
Formulation A 6.4 1110 21.2 86.4 100
(Standard
Method)
Completed 6.4 1085 21.2 86.4 12
Formulation A
(Nutrient
System)
Measurements are an average of 4 readings. %DO measured with Oakton DO 600
DO/Temp
Meter, pH/ppm/temperature measured with Bluelab Guardian and Nutradip meters.
22
CA 02919010 2016-01-22
Table 2: Dissolved Oxygen Content of Final Nutrient Solution
Time of Standard Nutrient
Measurement Method System
(%DO) (%DO)
Source Water 98.6 87.6
Filling 81.2 99.3
Formulation 85.7 100.7
Mixing 86.4 101.3
Dispensing 87.8 106.9
1 min. post 83.1 93.8
2 min. post 81.9 84.9
3 min. post 78.3 85.4
4 min. post 76.9 86.0
Measurements are an average from 2 samples. Measurements were taken of the
source water, at
filling of the reservoir, during formulation, mixing of the formulation,
immediately at dispensation,
and at 1, 2, 3, and 4, minutes post dispensation.
Conclusions:
[0075] The standard manual method, relying on manual agitation of the nutrient
solution
with the assistance of a pump, was not able to increase oxygen into the
solution let alone
maintain dissolved oxygen levels of the source water during preparation of the
formulation. Dissolved oxygen levels were found to rapidly decline throughout
the
process (Figure 10). In contrast, jet injection and circulation of the
nutrient solution during
preparation in the control system resulted in an increase in dissolved oxygen
levels of
about 18% at dispensation. Even after dispensing of the nutrient solution, the
dissolved
23
CA 02919010 2016-01-22
oxygen levels remained higher than dissolved oxygen levels of the nutrient
solution
prepared by the standard method.
[0076] Referring to Table 1, the preparation time for preparing the nutrient
solution from
filling to mixing and stabilizing the pH, was improved by 88% with the control
system over
the time needed for preparation by the standard method.
[0077] The disclosures of all patents, patent applications, publications and
database
entries referenced in this specification are hereby specifically incorporated
by reference in
their entirety to the same extent as if each such individual patent, patent
application,
publication and database entry were specifically and individually indicated to
be
incorporated by reference.
[0078] Although the invention has been described with reference to certain
specific
embodiments, various modifications thereof will be apparent to those skilled
in the art
without departing from the spirit and scope of the invention. All such
modifications as
would be apparent to one skilled in the art are intended to be included within
the scope of
the following claims.
24
