U.S. patent application number 10/834221 was filed with the patent office on 2005-11-03 for material classifier.
Invention is credited to Simpson, Peter.
Application Number | 20050242008 10/834221 |
Document ID | / |
Family ID | 35185997 |
Filed Date | 2005-11-03 |
United States Patent
Application |
20050242008 |
Kind Code |
A1 |
Simpson, Peter |
November 3, 2005 |
Material classifier
Abstract
The present invention a material classifier includes a cyclone
including a cyclone inlet, a cyclone outlet, a blower and a blower
discharge; an air diffuser connected at a diffuser inlet to the
cyclone outlet and at a diffuser outlet to an air lock such that
the cyclone and air diffuser are in fluid communication; wherein
the diffuser including a central cylindrical portion including an
air inlet for admitting controlled amounts of diffuser air around
substantially the entire cylinder outer periphery of the central
cylindrical portion, wherein the material classifier separating
fine particles from coarse particles and discharging the fine
particles together with air out the blower discharge, and
discharging the coarse particles through the air lock, such that
increasing the amount of diffuser air increases the size of the
fine particles being separated from the coarse particles.
Preferably wherein the diffuser air is admitted into the cyclone in
such a manner as to enhance and reinforce the formation of a strong
interior vortex.
Inventors: |
Simpson, Peter; (Hamilton,
CA) |
Correspondence
Address: |
KOCH LAW OFFICE
MARK A. KOCH
866 MAIN STREET EAST
HAMILTON
ON
L8M 1L9
CA
|
Family ID: |
35185997 |
Appl. No.: |
10/834221 |
Filed: |
April 29, 2004 |
Current U.S.
Class: |
209/717 |
Current CPC
Class: |
B04C 5/18 20130101; B01D
45/12 20130101; B04C 2009/002 20130101; B04C 5/13 20130101; B04C
9/00 20130101; B04C 5/04 20130101; B04C 5/14 20130101; B04C
2009/005 20130101 |
Class at
Publication: |
209/717 |
International
Class: |
B01D 009/00; B04C
005/06; B01D 059/50; B01D 053/00; B01D 051/00; B01D 050/00; B01D
049/00; B01D 047/00; B01D 046/00; B01D 045/00; B01D 041/00; B01D
057/00; B01D 039/00; B04C 005/02 |
Claims
I claim:
1. A material classifier comprising: a) a cyclone including a
cyclone inlet, a cyclone outlet, a blower and a blower discharge;
b) an air diffuser connected at a diffuser inlet to said cyclone
outlet and at a diffuser outlet to an air lock such that said
cyclone and air diffuser are in fluid communication; c) wherein
said diffuser including a central cylindrical portion including an
air inlet means for admitting controlled amounts of diffuser air
around substantially the entire cylinder outer periphery of said
central cylindrical portion, wherein said material classifier
separating fine particles from coarse particles and discharging
said fine particles together with air out said blower discharge,
and discharging said coarse particles through said air lock, such
that increasing the amount of diffuser air increases the size of
the fine particles being separated from the coarse particles.
2. The material classifier claimed in claim 1 wherein said diffuser
air is admitted into said cyclone in such a manner as to enhance
and reinforce the formation of a strong interior vortex.
3. The material classifier claimed in claim 2 wherein said air
inlet means including numerous air inlet apertures spaced around
said cylinder outer periphery for admitting diffuser air
4. The material classifier claimed in claim 2 wherein said air
inlet means including numerous air slots spaced around said
cylinder outer periphery for admitting diffuser air.
5. The material classifier claimed in claim 4 wherein said air
slots extending along a longitudinal axis, and said slots oriented
at an angle theta measured between said longitudinal axis and
vertical such that when diffuser air is admitted through said
angled slots said air flow supporting development of an interior
vortex in said cyclone.
6. The material classifier claimed in claim 5 wherein said angle
theta between 10 and 80 degrees.
7. The material classifier claimed in claim 4 wherein said slots
are so oriented so as to enhance and reinforce a formation of a
strong interior vortex.
8. The material classifier claimed in claim 1 wherein said air
inlet means further including a control means for adjustably
controlling the amount of diffuser air being admitted through said
air inlet means and into said air diffuser.
9. The material classifier claimed in claim 8 wherein said control
means including an annular adjustable band extending and clamping
around the cylinder outer periphery for selectively covering off
all or some of the slot area.
10. The material classifier claimed in claim 8 wherein said control
means including a barometric damper for adjusting the amount of
diffuser air depending upon the material through put of the
cyclone.
11. The material classifier claimed in claim 1 wherein said central
cylindrical portion being larger in diameter than a cyclone outlet
diameter.
12. The material classifier claimed in claim 11 wherein said
central cylindrical portion having a diameter at least 1.2 times
that of the cyclone outlet diameter.
13. The material classifier claimed in claim 1 wherein said cyclone
being a mid efficiency cyclone having a air inlet velocity of no
more than 3000 feet per minute.
14. The material classifier claimed in claim 1 wherein said cyclone
dimensioned and adapted to promote formation of an exterior
downwardly spiralling vortex and an up draft interior upwardly
spiralling vortex.
15. The material classifier claimed in claim 1 wherein said cyclone
further including a stand pipe dimensioned to aid and enhance the
development of a strong updraft interior vortex.
16. The material classifier claimed in claim 1 wherein said air
diffuser including an upper tapered portion for the transition
between the diffuser inlet and the central cylindrical portion.
17. The material classifier claimed in claim 1 wherein said central
cylindrical portion being a hollow body and a vertical length
greater than the diameter of the cyclone outlet.
18. The material classifier claimed in claim 1 wherein the
entrained particles being selected from the list including
granulate, pellets, fibres, flakes, beans, plastic, metal, and
paper.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to material classification
systems and in particular relates to material classifier using a
cyclone.
BACKGROUND OF THE INVENTION
[0002] In order to transport granular materials they are often
entrained in air or some gas. By fluidizing granular material in
air, one is capable of transporting the granular materials through
pipes, long distances to desired locations. Once the material has
reached its desired location, the material being transported must
be separated from the air which is usually accomplished with a
cyclone. Therefore in most material conveying systems using air
fluidization or entraining granular particles within air, the final
air material separation is often accomplished with a cyclone.
[0003] Furthermore, there is often the requirement that the
granular materials being transported, further needs to be
classified into different sizes. The most fundamental
classification that usually is required is separation of coarser
material from finer material for subsequent operations. There are a
number of existing devices which independently of the cyclone have
the capability of classifying materials into different sizes. It
would be desirable, however to use the cyclone in addition to its
air separating ability to also be able to classify the materials
into different sizes. This would eliminate an intermediate step and
the equipment associated with classifying granular materials into
various sizes.
[0004] There have been attempts at accomplishing this within the
cyclone, in for example prior art in International Application WO
03/033158 A1, titled Dust Separator, filed by Rapid Granulator AB
on Oct. 19, 2001, wherein they describe a cyclone which is used for
the separation of dust from granular material, using a separator
chamber mounted on the lower side of a cyclone. Particles dropping
out of the bottom of the cyclone pass into a separator chamber and
impinge upon a deflector device, wherein via this impact any dust
upon the particles settling out of the bottom of the cyclone is
dislodged and carried upward through a "inner wall" of the cyclone.
Further, the art teaches plates disposed within the inner walls,
whose purpose is to prevent or reduce rotation of the flow which
takes place with the major direction upwards within the "inner
wall" of the cyclone. An air inlet is located below the separator
chamber. A downwardly angled portion of the inlet conduit,
introduces air and is controlled by a regulator valve. The art
taught in this patent is directed towards removal of dust which is
adhered to larger granular particles. The apparatus intends to
dislodge the dust from the larger granular materials by impinging
the larger granular materials upon the deflector devices within a
separation chamber. This unit is limited to the collection and
removal of extremely fine dust particles from granular
materials.
[0005] There is however, a need to be able to use a cyclone as a
material classifier to be able to classify granular materials into
coarse and fine in addition to having the capability of dust
removal as indicated in the prior art PCT Application WO 03/033158
A1.
SUMMARY OF THE INVENTION
[0006] The present invention a material classifier includes:
[0007] a) a cyclone including a cyclone inlet, a cyclone outlet, a
blower and a blower discharge;
[0008] b) an air diffuser connected at a diffuser inlet to said
cyclone outlet and at a diffuser outlet to an air lock such that
said cyclone and air diffuser are in fluid communication;
[0009] c) wherein said diffuser including a central cylindrical
portion including an air inlet means for admitting controlled
amounts of diffuser air around substantially the entire cylinder
outer periphery of said central cylindrical portion, wherein said
material classifier separating fine particles from coarse particles
and discharging said fine particles together with air out said
blower discharge, and discharging said corse particles through said
air lock, such that increasing the amount of diffuser air increases
the size of the fine particles being separated from the coarse
particles.
[0010] Preferably wherein said diffuser air is admitted into said
cyclone in such a manner as to enhance and reinforce the formation
of a strong interior vortex.
[0011] Preferably wherein said air inlet means including numerous
air inlet apertures spaced around said cylinder outer periphery for
admitting diffuser air
[0012] Preferably wherein said air inlet means including numerous
air slots spaced around said cylinder outer periphery for admitting
diffuser air.
[0013] Preferably wherein said air slots extending along a
longitudinal axis, and said slots oriented at an angle theta
measured between said longitudinal axis and vertical such that when
diffuser air is admitted through said angled slots said air flow
supporting development of an interior cyclone in said cyclone.
[0014] Preferably wherein said angle theta between 10 and 80
degrees.
[0015] Preferably wherein said slots are so oriented so as to
enhance and reinforce a formation of a strong interior vortex.
[0016] Preferably wherein said air inlet means further including a
control means for adjustably controlling the amount of diffuser air
being admitted through said air inlet means and into said air
diffuser.
[0017] Preferably wherein said control means including an annular
adjustable band extending and clamping around the cylinder outer
periphery for selectively covering off all or some of the slot
area.
[0018] Preferably wherein said control means including a barometric
damper for adjusting the amount of diffuser air depending upon the
material through put of the cyclone.
[0019] Preferably wherein said central cylindrical portion being
larger in diameter than a cyclone outlet diameter.
[0020] Preferably wherein said central cylindrical portion having a
diameter at least 1.2 times that of the cyclone outlet
diameter.
[0021] Preferably wherein said cyclone being a mid efficiency
cyclone having a air inlet velocity of no more than 3000 feet per
minute.
[0022] Preferably wherein said cyclone dimensioned and adapted to
promote formation of an exterior downwardly spiralling vortex and
an up draft interior upwardly spiralling vortex.
[0023] Preferably wherein said cyclone further including a stand
pipe dimensioned to aid and enhance the development of a strong
updraft interior vortex.
[0024] Preferably wherein said air diffuser including an upper
tapered portion for the transition between the diffuser inlet and
the central cylindrical portion.
[0025] Preferably wherein said central cylindrical portion being a
hollow body and a vertical length greater than the diameter of the
cyclone outlet.
[0026] Preferably wherein the entrained particles being selected
from the list including granulate, pellets, fibres, flakes, beans,
plastic, metal, and paper.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 is an upright schematic perspective view of the
present invention a material classifier.
[0028] FIG. 2 is an upright schematic partial cut-away perspective
view of the present invention a material classifier.
[0029] FIG. 3 is a schematic perspective view of a regrind system
including the present invention a material classifier.
[0030] FIG. 4 is a schematic perspective partial cut away view of a
regrind system showing the present invention the material
classifier.
[0031] FIG. 5 is an upright schematic perspective view of the air
diffuser portion part of the material classifier.
[0032] FIG. 6 is a side plan elevational view of an alternate
embodiment of the body portion of a material classifier shown in
FIGS. 6, 8 and 9.
[0033] FIG. 7 is a upright schematic perspective view of an
alternate embodiment of a material classifier showing various inlet
heights.
[0034] FIG. 8 is an upright schematic perspective view of the
alternate embodiment of the material classifier shown in FIG. 7,
showing by way of example two different inlet angles, alpha and two
different bottom outlet diameters.
[0035] FIG. 9 is an upright schematic transparent view of an
alternate embodiment of the material classifier with a conical top
showing the interior vortex and the exterior vortex.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0036] The present invention a material classifier shown generally
as 20 is shown in FIG. 4 deployed together with other equipment
making up a regrind system shown generally as 22. Regrind system 22
takes plastic components and/or plastic parts or rejected plastic
parts and feeds them through a grinder shown generally as 501 which
produces granular material containing both coarser particles, finer
particles and of coarse also some dust. All of this granular
material is conveyed to material classifier 20, wherein the coarse
granular particles 106 are separated from the finer granular
particles 107 as well as dust which may be entrained, such that
coarse particles 106 are discharged from air lock housing 401 and
finer granular materials as well as dust together with air is
discharged from blower discharge 250 to bag house 502.
[0037] The present invention, material classifier shown generally
as 20 as shown in FIGS. 1 and 2 and includes the following major
components namely cyclone 100, blower 200, air diffuser 300 and air
lock 400. Cyclone 100 includes cyclone housing 101, tangential
cyclone inlet 102, cyclone outlet 103, internal stand pipe 104 and
blower air 105 shown generally as dark arrows. Note that blower air
105 shown as dark arrows will have entrained therein depending upon
the location within the process, coarse particles 106, fine
particles 107, diffuser air 304 as well as dust. Note that diffuser
air flow is generally shown as light or white arrows 108 and
diffuser air flow 108 will have entrained in it, depending upon the
location within the device, fine particles 107 as well as dust.
Cyclone 100 is the type known in the art and normally utilized for
separating air from particles entrained or fluidized in the
air.
[0038] Blower 200 includes the following major components, blower
housing 201 having mounted therein a fan 202 driven by a motor 203,
having a blower discharge 250, wherein blower 200 draws in blower
air 105 through cyclone inlet 102 and further through stand pipe
104 and out through blower discharge 250.
[0039] Air diffuser 300 includes a substantially hollow
cylindrically shaped diffuser housing 301, diffuser inlet 302,
diffuser outlet 303, diffuser air 304, shown generally as light or
white arrows 108. Diffuser air 108 is introduced into air diffuser
300 via air slots 305 which can be opened and closed with
adjustable band 302 having an adjusting bolt 310, such that
adjustable band 306 can be moved along vertical direction 330. FIG.
5 shows adjustable band 306 in the fully opened position 320 in
solid lines and the partially closed position 322 in dashed lines.
Diffuser housing 301 includes an upper tapered portion 312, a
central cylindrical portion 314, a lower tapered portion 314,
wherein diffuser inlet 302 has a inlet diameter 340 which is the
same as the cyclone outlet diameter and wherein central cylindrical
portion 314 has a cylindrical diameter 342.
[0040] Material classifier 20 further includes some type of air
lock 400 shown in these diagrams buy way of example only as a
rotary air lock 400, including an air lock housing 401, an air lock
inlet 402, a discharge 402 and a rotor 404. Kindly note that air
lock 400 can be any of the types known in the art, not necessarily
a rotary air lock as depicted here as long as the air lock 400 is
able to separate solid materials from air.
[0041] The regrind system shown generally as 22 in FIGS. 3 and 4,
includes a grinder 501 having a grinder housing 503, and a raw
material inlet 502 further including piping 511 for transportation
of granular material to the material classifier 20. Prior to the
fluidized material entering cyclone 100, it is preferably passed
through an anti-static system 110, wherein charged particles 172
enter into anti-static system 110 are neutralized such that
uncharged coarse particles 106 leave anti-static system 110.
Anti-static system 110 will neutralize both coarse and fine
particles as well as dust particles, even though this is not
depicted in the drawings. Material classifier 20 separates coarse
particles which exit through the bottom of discharge 403 of air
lock 400, wherein fine particles 107 exit at blower discharge 250
via piping 511 to a bag house 502 which includes a plenum 505, air
filters 506 and fine containers 507.
[0042] In Use
[0043] Granular material is received into cyclone 100 through
cyclone inlet 102 which is positioned in such a manner to set up
cyclonic motion within cyclone housing 101 as depicted
schematically with the dark black arrows which are denoted as
blower air 105. Blower 200 having fan 202 driven by fan motor 203,
creates a vacuum or suction on cyclone inlet end 102 and draws
granular material in through cyclone inlet 102. Granular material
normally includes coarse particles 106, fine particles 107, and
dust particles not shown as well as blower air 105 all mixed
together at cyclone inlet 102. Cyclone inlet 102 is normally
positioned above a vertical stand pipe 104 centrally and coaxially
mounted within cyclone housing 101. This cyclone geometry well
known in the art creates a circular flow around the exterior
portion of cyclone housing 101 as depicted by the dark arrows of
blower air 105 and the heavier coarse particles 106 through
centrifugal force are swept to the exterior periphery of cyclone
housing 101 and make their way downwardly in vertical direction 191
towards cyclone outlet 103. Blower air 105 drawn into fan 202 of
blower 200 enters stand pipe 104 and up and through fan 202 and out
blower discharge 250.
[0044] It is believed that an up draft and or a counter rotating
vortex is created vertically below stand pipe 104 which typically
provides for the removal of blower air 105 through blower 200 and
out through blower discharge 250.
[0045] Therefore there is an exterior spirally downwardly rotating
vortex 701 with heavier coarser particles 106 entrained therein and
moving vertically downwardly along vertical direction 191 and there
is an interior updraft or spirally upwardly counter rotating vortex
702 developed proximate the central portion of cyclone housing 101
and in this manner blower air 105 is removed from cyclone housing
101 at times together with dust out of blower discharge 250.
[0046] Prior art International Application WO 03/033158 A1 adds an
additional separator chamber 18 below cyclone 100 which has mounted
therein a deflector device 19, wherein coarser particles impinge
upon the deflector device, such that additional dust is dislodged
from coarser particles and by additionally allowing air to enter
below a separator chamber, this dust is then carried out with the
air discharge rather than through the air lock.
[0047] In the present invention as coarse particles 106, together
with fine particles 107 as well as dust, makes its way downwardly
in cyclone 100 towards cyclone outlet 103 and into air diffuser
300, particles of all sizes meet with diffuser air 304 which is
allowed to enter through air slots 305 which are defined around the
entire cylinder outer periphery 350 of central cylindrical portion
314 of diffuser housing 301.
[0048] Diffuser air 304 entering through air slots 305 defined
around the entire cylinder out periphery 350, fluidizes or
entrains, fine particles by supporting and enlarging the up draft
interior vortex 702 and effectively strengthens the upward force of
interior vortex 702 and diffuser air 304 rising upwardly into stand
pipe 104 creates a strong upward draft such that by controlling the
amount of diffuser air 304, one controls the strength and velocity
of air within interior vortex 702 and in this manner, one can
control the size of particles which are fluidized by interior
vortex 702 and which eventually make their way through blower 200
and out through blower discharge 250.
[0049] Experimentally, it has been found that it is important to
support the existing up draft interior vortex 702 as well as the
exterior vortex 701 through the design of the inlet of diffuser air
304 into cyclone 100.
[0050] Unlike the prior art as described in WO 03/033158 A1 which
in fact indicates that they are using plates within a the stand
pipe for the purpose of preventing or reducing rotation of flow
which takes place with the major direction upwards inside the inner
walls. The present invention utilizes the existing upwards flow
within cyclone by controllably strengthening and enhancing the up
draft flow within the interior vortex 702 in order to selectively
fluidize particles of pre determined size.
[0051] As a result, it has been found that by angling air slots 305
at an angle theta 344 measured between a longitudinal axis 345 and
the vertical direction 191, one is able to enhance and encourage
the up draft interior vortex 702 by placing the air slots 305
around cylinder outer periphery 350 in an angled relationship
having an angle theta 344 as shown in FIG. 5. Adjustable band 306
having an adjustment bolt 310 is strapped around central
cylindrical portion 314 of air diffuser 300 and can be adjusted by
loosening off bolt 310 to a fully opened position as shown in 320
in FIG. 5 or a partially closed position 322 as shown as dashed
lines in FIG. 5 or in fact it can fully close off air slots 305 by
placing adjustable band 306 entirely covering air slots 305.
[0052] Through trial and error and experimentation it has been
found that it is important that central cylindrical portion 314
have a cylinder diameter 342 larger than inlet diameter 340 which
is basically the same diameter as cyclone outlet 103. It has been
found that in order to enhance and aid the interior vortex 702
development, one needs to introduce diffuser air 304 at a cylinder
diameter 342 which is larger than the cyclone outlet diameter 103.
In addition, it has been found very important that air be
introduced around the entire periphery of cylinder outlet 350,
rather than at just a single point, once again in order to aid the
development and strength of interior vortex 702 which is rotating
counter clock wise and rising upwardly within cyclone housing
101.
[0053] In practice one has been able to control the classifier such
that the material size exiting out of blower discharge 250 can be
carefully controlled by allowing more or less diffuser air 304
through air slots 305 of air diffuser 300. The heaviest particles
will immediately tend to the outer diameter of cyclone housing 101
and will drop through air diffuser 300 undisturbed and into air
lock 400.
[0054] However by introducing more diffuser air 304 through air
slots 305, the interior vortex 702 becomes stronger and more fully
developed and will fluidize and carry upwardly larger and larger
granules of particles up through stand pipe 104 and out through
blower discharge 250, such that one can select the size of
particles into at least two distinct sizes, namely coarser
particles 106 and fine particles 107, in addition to dust
removal.
[0055] A person skilled in the art will note that cyclone 100 in
any event removes dust particles not shown in the attached diagrams
and the prior art in International Application WO 03/033158 A1 has
indicated a method or a means of adding or enhancing dust removal
through a conventional cyclone 100.
[0056] In addition to dust removal, material classifier 20 has the
capability of selectively removing heavier particles and in fact
can classify incoming particles into at least two classifications
namely coarse particles 106 which are discharged from discharge 402
of air lock 400 and fine particles 107 which are discharged from
blower discharge 250. The fine particle size can be controllably
selected by adjusting the amount of diffuser air 304.
[0057] Material classifier 20 appears to be most effective when
using a mid-efficiency cyclone 100 rather than a high efficiency
cyclone. A mid efficiency cyclone generally has an air velocity of
less than 3000 feet/min. High efficiency cyclones tend to be
smaller in diameter and longer in length and have a strong exterior
vortex 701 and it is the inventors theory that the interior vortex
702 tends to be extremely weak and therefore it is difficult to
support and/or enhance the interior vortex 702 development with the
addition of diffuser air 304 through air slots 305. In any event,
through trial and error and experimentation, it has been found that
a larger diameter cyclone 100 known in the industry as a mid
efficiency cyclone, appears to develop a very strong interior
vortex 702 which can be enhanced and utilized with the introduction
of diffuser air 304 through air slots 305.
[0058] Material classifier 20 is shown in a typical installation of
a regrind system 22 as depicted schematically in FIGS. 3 and 4.
[0059] By way of example only and without limitation, a plastic
regrind system takes existing plastic components or scrap from
injection moulding machines or blow moulding machines and regrinds
this plastic for later reuse. The plastic is introduced into
grinder 501 through raw material inlet 502 and via piping 511 is
conveyed in an air fluidized manner to material classifier 20,
wherein both coarse particles 106 and fine particles 107 enter
material classifier 20 along with dust of coarse, and wherein
through the cyclonic action of cyclone 100, the larger particles
fall quickly to the cyclone outlet 103 and out through air diffuser
300 and into air lock 400, where they are dropped into material
container 504. Depending upon the amount of diffuser air 304 which
one selects to enter through air slots 305, the lighter, smaller
granular particles as well as dust is carried upwardly with
interior vortex 702, up through blower 200 and out through blower
discharge 250. Therefore, larger particles of a certain size are
discharged through air lock 400 and smaller particles of a certain
size are discharged through blower discharge 250.
[0060] In order to separate blower air 105 from fine particles 107
and dust which also may be entrained, a bag house 502 is employed,
wherein the air and particles discharged from blower discharge 250
pass through plenum 505 and drop down through air filters 506
wherein air is discharged and fine granular material is collected
in fines containers 507.
[0061] In this manner a person skilled in the art will note that
various granular materials can be classified using material
classifier 20 including plastic materials, grains, sands, coffee,
wood chips, rubber granular materials, fibre granular materials,
plastics from metal, jute from wire, filaments and many other
granular type materials too numerous to list here.
[0062] Further it has been found that by using a barometric damper
(not shown in the drawings) to control the amount of diffuser air
304 one can compensate for through put variations such as material
surges or variations in material through put rates. The barometric
damper would have an upstream sensor placed prior to cyclone inlet
102 which would adjust diffuser air 304 amounts according to
material through put.
Description of Alternate Embodiment
[0063] An alternate embodiment of the material classifier is shown
in FIGS. 6, 7, 8 and 9 and is shown generally as material
classifier 700 which operates in an analogous fashion as material
classifier 20 with the following modifications and improvements to
the cyclone.
[0064] Material classifier 700 includes a conical top 720 having a
top diameter 712, a cylindrical section 714 and a conical bottom
section 710. It further includes cyclone inlet 102 which can
positioned at different inlet height 704 and/or different inlet
angles alpha 706. In addition, conical bottom 710 may have a
differing bottom outlet diameter 708 as shown particularly in FIG.
8 in dashed lines being the larger bottom outlet diameter 708 and
the solid lines being the smaller bottom outlet diameter 708.
[0065] Referring now to FIG. 9 which shows schematically the
development of the interior vortex 702 which is rising upwardly and
development of the exterior or vortex 701 which is moving
downwardly. The modifications to material classifier 700 will now
be explained in regard to optimizing the development and strength
of interior vortex 702 which carries out fines through blower
discharge 250.
[0066] It has been found by trial and error that in order to
encourage development of the updraft in interior vortex 702 and
more efficient separation of coarse particles 106 from fine
particles 107, a number of modifications to the cyclone have been
shown to help develop a stronger interior vortex 702. In particular
the inlet height 704 shown in FIG. 7 will aid in the development of
interior vortex 702 as well as the inlet angle alpha 706 as shown
in FIG. 8 and FIG. 6 and as well by adding a conical top section
720 on top of cylindrical section 714, one also is able to enhance
and aid the development of a strong interior vortex 702.
[0067] The inventor has also found that by having a smaller bottom
outlet diameter 708 as shown in FIG. 8, one can also increase the
updraft or the strength of interior vortex 702 within material
classifier 700.
[0068] By optimizing inlet height 704, inlet angle alpha 706,
bottom outlet diameter 708 as well as by the addition of a conical
top section 720, one can customize material classifier 700 to
separate the coarse particles 106 from fine particles 107.
[0069] It should be apparent to persons skilled in the arts that
various modifications and adaptation of this structure described
above are possible without departure from the spirit of the
invention the scope of which defined in the appended claim.
* * * * *