Note: Descriptions are shown in the official language in which they were submitted.
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Description
FOOD WASTE TREATMENT APPARATUS USING
MICROWAVE
Technical Field
[1] The present invention relates to a food waste treatment apparatus for
disposing,
drying, and recycling food waste as compost, and a nature-friendly food waste
treatment apparatus for drying food waste using microwaves, capable of
enhancing
drying efficiency, and removing odor and vapors generated during the drying
process
using ozone and a variety of filters.
Background Art
[2] Generally, food waste treatment is very difficult. That is, it is
difficult to incinerate
food waste or to bury the food waste in landfills because it contains a large
amount of
water. Further, standards for food waste treatment are becoming strict.
[3] An example thereof is the regulation on food waste sorting and discharge.
According to this regulation, food waste must be separated from other waste
and
discharged using a separate food waste bag. Even in this case, since the food
waste
contains a large amount of water, it easily decomposes in a food waste bag,
thereby
causing odor and polluting the surroundings with leachate.
[4] In the ideal food waste discharge state, the food waste contains almost no
moisture.
However, it is difficult to completely dehydrate food waste using recent
technologies.
[5] Further, even though food waste contains many valuable contents worth
recycling,
the food waste is generally buried as it is because it is very difficult to
treat and
separate the valuable content from the food waste. That is, although the food
waste can
be used as feedstuff for animals or as compost after treatment that includes
steps of
pulverizing, drying, and mixing the food waste with other material, the food
waste is
generally discarded without being reused.
[6] Accordingly, in order to reuse the food waste from houses and restaurants,
the food
waste must be discharged in a dehydrated state.
[7] In consideration of the above problems, several kinds of food waste
treatment
apparatus have been developed.
[8] One example of a conventional food waste dehydration apparatus is
disclosed in
Korean Patent Application No. 10-1997-0081044, and uses microwaves. The food
waste dehydration apparatus includes a dry compartment having a space in which
food
waste can be stored, pulverized and dried, a rotating axis installed in the
dry
compartment, a mixing blade rotating along with the rotating axis, and a
magnetron for
heating food waste in the dry compartment. However, this apparatus has a dis-
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advantage in that it takes a long time to dry food waste and it cannot dry
food waste
continuously.
[9] A further dehydration apparatus entitled "a coating liquid drying
apparatus using
microwaves" is disclosed in a Korean patent application assigned Application
No.
10-2000-0001881.
[10] FIG. 1 is a perspective view and a sectional view illustrating the
structure of the
coating liquid drying apparatus using microwaves according to the conventional
art.
The apparatus is installed on a moving path of an object to be coated in
coating
equipment for continuously fonning coating layers on the surface of an object,
and
comprises a box-type housing 3, at least one magnetron 1 installed on the
housing 3 for
radiating microwaves into the housing 3, a power supply unit 14 and a
controller 15 for
driving and controlling the operation of the magnetron 1 installed outside the
housing
3, a pull-in unit 17 and a pull-out unit 18 installed inside and outside an
entrance of the
housing 3 and having a microwaves shielding film 11 therein, and an air
ventilation fan
12 and an air ventilation pipe for exhausting vapors and volatile solvents
from coating
liquid when drying the coating liquid.
[11] The coating liquid drying apparatus according to the conventional art
radiates
microwaves on the coating liquid like a flashlight, so that there is a dead
zone in which
microwaves do not reach the object to be dried, and thereby it has low drying
efficiency. Accordingly, it is difficult to dry food waste containing a large
amount of
water.
Disclosure of Invention
Technical Problem
[12] Accordingly, the present invention has been devised in consideration of
the afore-
mentioned problems and situations, and it is an object of the present
invention to
provide a nature-friendly food waste treatment apparatus using microwaves,
capable of
continuously supplying pulverized food waste on an endless track, capable of
eliminating odors, and having enhanced drying efficiency.
Technical Solution
[13] In order to achieve the above objects and advantages, according to one
aspect of
the present invention, there is provided a food waste treatment apparatus
using
microwaves, comprising a pulverizer for pulverizing food waste, a quantitative
discharger for discharging the pulverized food waste at regular discharge
rates using a
pump, a plurality of containers installed on an endless track for storing and
transferring
the pulverized food waste discharged from the quantitative discharger, a
microwave
dryer installed above the container for drying the pulverized food waste in a
manner
such that microwaves are created by a magnetron and are reflected in a
direction per-
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pendicular to a horizontal direction which is a moving direction of the
containers, and
a post-treatment unit connected to a side of the microwave dryer for removing
odors
and vapors.
[14] The microwave dryer may comprise a magnetron for creating microwaves, and
a
reflection means for reflecting the microwaves incident in a horizontal
direction to
direct the microwaves in a vertical downward direction, the reflection means
having a
fixed plate inclined at 45 degrees with respect to the horizon direction and
rotated by
being connected to a step motor.
[15] The reflection means may comprise two reflection means having different
sizes.
[16] The reflection means may comprise two reflection means having different
sizes
whose ratio is 3:2.
[17] The microwave dryer may have a tunnel-type housing, three reflection
means
installed in the housing, and three magnetrons corresponding to respective
reflection
means.
[18] The housing may have respective shielding doors at an entrance side and
an exit
side thereof, thereby shielding the microwaves and preventing the microwaves
from
leakage.
[19] The post-treatment unit may comprise an ozone generator, for supplying
ozone to
the odors and a variety of filters.
[20] The food waste treatment apparatus may further comprise a rotating brush
installed
under the endless track for removing residue sticking to an inner surface of
the
container.
[21] According to a further aspect of the present invention, there is provided
a food
waste treatment apparatus using microwaves, comprising a pulverizer for
pulverizing
food waste to a mash form and discharging in a downward direction, an endless
track,
installed under the pulverizer, moving in a continuous manner, and being made
of
material through which microwaves pass, for transferring pulverized food
waste, a
reflection plate installed in a space provided by the endless track, in a
manner such that
the reflection plate is distanced from the endless track, a microwave dryer
installed
above the endless track for radiating microwaves created by a magnetron in a
downward direction, and a post-treatment unit connected to the microwave dryer
for
removing odors and vapors.
[22] The food waste treatment apparatus may further comprise a rotating feeder
disposed between the pulverizer and the endless track for supplying pulverized
food
waste on a surface of the endless track.
[23] The reflection plate may have a plurality of bars arranged in a length
direction and
coupled to each other on a surface thereof.
[24] The microwave dryer may comprise a chamber installed on a surface of the
endless
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track and connected to the reflection plate, having an empty space therein, a
plurality
of magnetrons installed above the chamber, and a reflection inducing body
installed in
the chamber at an upper part of the chamber, and installed between the
magnetrons in a
length direction, the reflection inducing body having a structure in which a
thickness
thereof becomes smaller in a downward direction.
[25] The endless track may be coated with silicon.
[26] The pulverizer may comprise a cylindrical casing having an open upper end
and an
open lower end, a pulverizing plate coupled to the lower end of the
cylindrical casing,
and having a plurality of depressions arranged in a radial manner on a first
portion of
an upper surface thereof, and having a plurality of through holes at a second
portion
other than the first portion, and a pulverizing rotary unit coupled to the
pulverizing
plate and installed above the pulverizing plate, and having a plurality of
pulverizing
cutters, each protruding from an upper surface thereof and being defined by a
plurality
of divisional depressions.
[27] The food waste treatment apparatus may further comprise a screen mesh
disposed
on an upper surface of the second portion of the pulverizing plate.
[28] The pulverizing cutter may have a reverse trapezoid shape in which a
front surface
and respective side surfaces are inclined inward.
Advantageous Effects
[29] The food waste treatment apparatus according to the present invention has
the
following advantages.
[30] First, it has enhanced drying efficiency because microwaves is irradiated
on food
waste in a direction perpendicular to the food waste, and can reduce costs by
decreasing a cycle time.
[31] Second, it is a nature friendly apparatus and maintains a comfortable
indoor en-
vironment by eliminating odors when it dries food waste.
[32] Third, it can pulverize food waste into a mashed form, and enhance drying
efficiency by reflecting microwaves two times in a chamber using a reflection-
inducing body and a reflection plate, so that the microwaves head in an upward
direction and then a downward direction in the chamber.
Brief Description of the Drawings
[33] The advantages and features of the present invention may be understood
more
readily with reference to the accompanying drawings, but the present invention
should
not be construed as being limited to the accompanying drawings. Further,
simple mod-
ification and replacement of elements of the present invention may be
considered as
being included in the scope of the present invention.
[34] FIG. 1 is a perspective view and a sectional view illustrating a coating
liquid
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drying apparatus using microwaves according to the conventional art;
[35] FIG. 2 is a schematic front view illustrating a food waste treatment
apparatus
according to one embodiment of the present invention;
[36] FIG. 3 is a schematic diagram illustrating the combination of a microwave
dryer
and a post-treatment unit of the food waste treatment apparatus according to
the
present invention;
[37] FIG. 4 is a perspective view illustrating the food waste treatment
apparatus
according to the present invention, in which the microwaves drying unit and
the post-
treatment unit are integrated into a single body;
[38] FIG. 5 is a schematic view illustrating the detailed inner structure of
the
microwaves drying unit;
[39] FIG. 6 is a plan view illustrating a reflection means;
[40] FIG. 7 is a schematic view illustrating a food waste treatment apparatus
according
to a further embodiment of the present invention; and
[41] FIG. 8 is an exploded perspective view illustrating the food waste
treatment
apparatus shown in FIG. 7.
Best Mode for Carrying Out the Invention
[42] Hereinafter, a food waste treatment apparatus using microwaves according
to the
present invention will be described with reference to the accompanying
drawings.
[43] FIG. 2 is a front view and FIG. 3 is a schematic diagram illustrating the
food waste
treatment apparatus according to one embodiment of the present invention.
[44] Referring to FIG. 2 and FIG. 3, the food waste treatment apparatus
comprises a
pulverizer 10, a quantitative discharger 20, a microwave dryer 40, and a post-
treatment
unit 50. Food waste is introduced into the pulverizer 10 through an upper part
thereof,
and is pulverized therein by rotating cutters, so that the food waste is
changed into a
mashed form.
[45] The mashed food waste is forcedly transferred to the quantitative
discharger 20 by
a pump, and is discharged at a predetermined rate through a nozzle 25. The
pulverizer
and the quantitative discharger 20 are selected from the conventional ones, so
a de-
scription of their details will be omitted.
[46] Referring to FIG. 2, an endless track 30a is installed, and a plurality
of the
containers 30 is arranged in a row on the endless track 30a. The containers 30
con-
tinuously move along with the endless track 30a, and receive and store the
mashed
food waste discharged from the nozzle 25 of the quantitative discharger 20.
[47] The discharging of the mashed food waste is intermittently performed
through the
nozzle 25. That is, when one container is disposed under the center of the
nozzle, the
food waste is discharged into the container from the discharger, and the
discharging of
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the food waste is intercepted while the containers move. The discharging of
the food
waste can be controlled according to the moving speed of the endless track so
that the
food waste can be introduced into the containers.
[48] The microwave dryer 40 is installed above the container 30 in a manner
such that
microwaves reach the surface of the food waste in the container 30 moving in a
horizontal direction, in a direction perpendicular to the surface of the food
waste,
thereby enhancing drying efficiency. If it is needed, a plurality of microwave
dryers
can be installed in order to more highly enhance the drying efficiency.
[49] FIG. 4 illustrates the microwave dryer and FIG. 5 illustrate the inside
structure of
the microwave dryer.
[50] The microwave dryer 40 includes a magnetron 41 for creating microwaves.
The
magnetron 41 is a conventional one, so a detailed description thereof will be
omitted.
[51] The microwave dryer 40 further includes a reflection means 42 disposed
near the
magnetron 41. The reflection means 42 is connected to a step motor 43 and is
rotated
by the step motor 43. The reflection means 42 has a plate 42-2 that is fixed
to an edge
of an arm 42-1 and inclined inward at 45 degrees from a horizontal direction,
so that
microwaves created by the magnetron 41 and incident onto the plate 42-2 in a
horizontal direction are reflected from the plate 42-2 and then head in a
vertical
direction after being reflected.
[52] FIG. 6 is a plan view illustrating the reflection means. Referring to
FIG. 6, the
reflection means includes three arms 42-1, each arranged at an angle of 120
degrees.
The plates 42-2 are connected to the respective ends of the arms 42-1.
[53] Referring to FIG. 5, the microwave dryer 40 comprises a plurality of
pieces of the
reflection means 42 connected in series in a vertical direction. According to
this
embodiment of the present invention, two reflection means 42 having different
sizes
are installed and are connected to the step motor 43. The ratio of sizes of
the two
reflection means 42 is preferably 3:2. According to need, three or more
reflection
means 42 can be included.
[54] Referring to FIG. 4, the microwaves drying unit 40 has a housing 40a
having a
long tunnel shape, and has three magnetrons 41. In this case, three reflection
means 42,
corresponding to the three magnetrons 41, are installed in the housing 40a.
[55] The post-treatment unit 50 purifies air by absorbing odors and vapors
generated
during the drying process performed by the microwave dryer 40.
[56] For post-treatment, a suction duct 51 is connected to the microwave dryer
40, and a
suction blower 52 and a mixer 53 are installed. The suction blower 52 sucks
odors and
mixes the collected odors with ozone. For ozone mixing, an ozone generator 54
is
included. As the odors mix with ozone from the ozone generator 54, the odors
are
preliminary purified.
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[57] The odors purified by the mixer 53 and vapors are transferred to a
variety of filters
55. Examples of the filters 55 include a carbon filter, a zeolite filter, and
a P.P. filter.
The numbers and types of the filters vary according to need. The post-
treatment unit 50
preferably further includes a condensation means 56 for condensing vapors,
thereby
separating the vapors from air.
[58] The odor is further purified by the filters 55 and the condensation means
56, so that
finally emitted air does not contain hazardous components.
[59] In the case of the tunnel-shape microwave dryer, as shown in FIG. 4,
three suction
ducts 51 are connected to the housing 40a to eliminate odors.
[60] As shown in FIG. 2, the food waste treatment apparatus according to the
present
invention, as shown in FIG. 2, preferably includes a rotating brush under the
endless
track 30a. The mashed content in the container 30 is dehydrated by the
microwave
dryer 40 and moves along the endless track 30a, so that the dehydrated food
waste is
transferred to a separate food waste collection container. Respective empty
containers
continuously move along the endless track 30a for continuous drying, and are
filled
with mashed food waste when they are disposed under the nozzle.
[61] When emptying the containers, there can be residue in the bottoms of the
containers. Accordingly, the rotating brush is provided to remove the residue
from the
containers when emptying the containers. The rotating brush removes the
residue by
being in contact with the bottom of the container.
[62] The operational principles of the food waste treatment apparatus
according to the
present invention will be described below.
[63] Food waste is introduced into the pulverizer and is then pulverized in
the
pulverizer. The pulverized food waste is discharged to the containers disposed
under
the nozzle using the quantitative discharger and the pump. That is, the
containers
installed on the endless track are then sequentially filled with the
pulverized food
waste and move along the endless track, thereby sequentially entering into the
microwave dryer. The food waste in the containers is dried rapidly in the
microwave
dryer. Since a plurality of reflection means is arranged in series, it is
possible to
enhance the drying efficiency and is possible to continuously dehydrate food
waste
using containers moving along the endless track.
[64] After the food waste passes out of the microwave dryer, the dehydrated
food waste
is collected in the separate food waste collection container, and the food
waste can be
continuously dried as the containers move and enter the microwave dryer
continuously.
[65] The odors and vapors generated during the drying process using the
microwave
dryer are purified by the post-treatment unit and then are discharged into the
air.
[66] Referring to FIG. 7, a food waste treatment apparatus according to a
further
embodiment of the present invention will be described. FIG. 7 is a plan view
il-
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lustrating the food waste treatment apparatus according to this embodiment of
the
present invention, and FIG. 8 is an exploded perspective view illustrating the
pulverizer of this apparatus.
[67] The food waste treatment apparatus according to the further embodiment of
the
present invention includes a pulverizer 100, an endless track 200, a
reflection plate
300, a microwave dryer 400 and a post-treatment unit (not shown). The
pulverizer 100
pulverizes the food waste into a mashed form, and discharges the mashed food
waste.
[68] The pulverizer 100 includes a cylindrical casing 110 having an open upper
end and
an open lower end, and a pulverizing plate 120 coupled to the lower end of the
cylindrical casing 110. The pulverizing plate 120 has a disk shape, and has
depressions
125 formed on an upper surface thereof in a first zone thereof, and has a
plurality of
through holes 127 in a second zone other than the first zone where the
depressions 125
are formed.
[69] As shown in the drawings, the area of the second zone in which the
through holes
127 are formed is about a quarter of the entire area of the pulverizing plate
120, and the
depressions 125 are formed in the second zone, which occupies three quarters
of the
entire area of the pulverizing plate 120.
[70] The depressions 125 can be preferably also formed in the second zone
between the
through holes 127.
[71] More preferably, a screen mesh 129 can be installed on the pulverizing
plate 120 in
the first zone where the through holes 127 are formed, so that insufficiently
pulverized
food waste is prevented from being discharged through the through holes 127.
[72] Further, a pulverizing rotary unit 130 is disposed on the surface of the
pulverizing
plate 120 and a shaft is installed in the center of the pulverizing rotary
unit 130
connected to a motor.
[73] The outermost diameter of the pulverizing rotary unit 130 is the same as
a diameter
of an imaginary circle formed by an imaginary line connecting the depressions
125. A
plurality of divided depressions 135 arranged at regular intervals forms
protruding
pulverizing cutters 137. In this embodiment, there are six cutters.
[74] The pulverizing rotary unit 130 is combined with the pulverizing plate
120 and is
distanced from the surface of the pulverizing plate 120, and pulverizes food
waste by
rotating the pulverizing plate 120.
[75] The front surface and respective side surfaces of the pulverizing cutter
137 incline
inward, so that the pulverizing cutter 137 has a reverse trapezoid shape.
Since the front
end and respective sides of the pulverizing cutter 137 are inclined, food
waste can
more easily pass between the cutters 137, so that the food waste can be more
thoroughly pulverized.
[76] The food waste pulverized by the pulverizer 100 is discharged through the
through
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holes 127, and a food waste feeder 150 is installed under the through holes
127. The
feeder 150 is a rotating body having a plurality of depressions formed at
regular
intervals. The food waste is introduced into the depressions, and is then
rotated by the
rotating body. The food waste falls down, and is finally scattered on the
surface of the
endless track.
[77] The endless track 200 engages with a pulley P so that it can move
endlessly.
[78] The endless track 200 is made of material through which microwaves can
penetrate
and which can endure a high temperature of about 800 to 900 C. For example,
the
endless track 200 is made of a fabric woven with silicon dioxide fiber, or
with glass
fiber.
[79] The endless track 200 may be coated with a silicon layer on the surface
thereof.
Thanks to the silicon layer, the dried food waste is more easily pulverized.
[80] The reflection plate 300 is installed in a space provided by the endless
track 200 in
a manner such that it is separated from the endless track 200 and is not in
contact with
the endless track 200. The reflection plate 300 may be a metal plate. The
distance
between the surface of the reflection plate and the endless track can be
adjusted
according to need.
[81] A plurality of bars b is arranged on the surface of the reflection plate
300 at regular
intervals in a length direction, in a manner such that the bars b are not in
contact with
the inner surface of the endless track and cannot be loosened in the vertical
direction.
[82] The microwaves drying unit 400 is installed above the endless track 200
and
includes a magnetron that creates microwaves and radiate the microwaves in the
vertical direction.
[83] The microwaves drying unit 400 includes a chamber 410, a magnetron 420,
and a
reflection-inducing body 430. The chamber 410 is installed above the endless
track
200, is connected to the reflection plate 300, and has an empty space therein.
[84] The magnetron 420 is installed above the chamber 410, generates
microwaves and
radiates them into the chamber 410. The plurality of reflection-inducing
bodies 430 is
installed in the chamber 410 at an upper part thereof between the plurality of
magnetrons 420.
[85] Each of the reflection-inducing bodies 430 has a shape in which the
thickness
thereof decreases from an upper part to a lower part. According to this
embodiment,
the reflection-inducing body 430 is formed in a stepwise shape, and has a
sharp lower
end. Thanks to the above-described structure of the reflection inducing body,
the total
surface area of the reflection-inducing body increases, thereby enhancing the
microwave reflection efficiency.
[86] Thanks to variation of thickness of the reflection-inducing body, a dead
zone,
which microwaves do not reach, does not exist.
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[87] The microwaves created by the magnetron 420 are reflected from the
reflection-
inducing bodies 430, head in the downward direction, pass through the endless
track
200, are reflected again from the surface of the reflection plate 300, and
head in an
upward direction, thereby drying the food waste on the endless track with high
drying
efficiency.
[88] The odors and vapors produced from the pulverized food waste and dried by
the
microwaves are removed by the post-treatment unit (not shown). The post-
treatment
unit in the apparatus according to this embodiment is the same as that in the
apparatus
according to the previously described embodiment. The odors and vapors are
collected
through a duct connected to the chamber, and a detailed description thereof
will be
omitted.
Industrial Applicability
[89] The food waste treatment apparatus according to the present invention has
high
drying efficiency, thereby being capable of being used widely in houses and
restaurants. The food waste treatment apparatus according to the present
invention can
be used as a sludge dehydration apparatus.
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