Abstrict A mobile fluorescent lamp digesting system which crushes, cleans
and classifies various lamp components into distinct groups i.e.
clean glass, phosphor powder and metal end-caps, utilizing a crusher
fan mounted inside a screen drum which is mounted on single rotating
axis. An air knife is directed into fractured material during processing
further enhancing cleaning action. The system is operated under
negative air pressure to collect any ambient phosphor dust and or
mercury vapor via a two stage filtering arrangement. First stage
filter media is resistant to plugging by fine dust. The second stage
is activated carbon media to collect metallic mercury vapors. Classified
components are neumatically transported into collection chambers
or drums after processing is completed for easy handling.
Claims I claim:
1. A mobile fluorescent lamp digester system where lamps are crushed,
cleaned of any powder residue and where material components used
to construct the lamps are classified into three distinct groupings
during processing: clean glass, mercury rich phosphor powder and
metal end-caps; where specified operations are performed at an angle
to the horizon on a single rotating axis comprising:
(a) a rotating crusher fan mounted on one side of a plate where
the single rotating axis is joined to the center of the plate and
where a plurality of crusher fan blades equally spaced are arranged
and constructed at angle of pitch where a leading edge impacts incoming
lamps and where trailing edge forces fractured material through
the crusher fan continuously recirculating fractured material up
and around through friction media thereby enhancing cleaning of
fractured material due to an increase in turbulance and friction
caused specifically by recirculation;
(b) a rotating tumbler screen drum member affixed to an outside
edge of the plate parallel to the axis extending over the crusher
fan where the crusher fan is mounted inside the screen drum where
the screen drum is perforated with small openings near the crusher
fan having progressively larger opennings toward a mouth of the
screen drum mouth where fractured material enters at one end and
sifts out, through perforated openings via rotating action and gravitational
forces, into distinct classifications;
(c) said friction media located inside the screen dram where the
drum angle is such that friction media remains at the dram bottom
surrounding the crusher fan; where the friction media is comprised
of varying type, size and mass density of particles for purposes
of cleaning fractured material via frictional forces during rotation
of the drum.
2. A digester system in accordance with claim 1 constructed to
be portable or mobile mounted on wheels, able to be transported
from location to location as a generator operated or mobile unit.
3. A digester system in accordance with claim 1 constructed to
classify processed lamps into distinct material groups such as clean
glass, phosphor powder and metal end-caps, by using said rotating
screen arrangement.
4. A digester system in accordance with claim 1 constructed such
that an air knife has blown through at varying velocities and pressures
via a blower device where a nozzle is mounted on a tube end and
is able to direct and control gas departure from said air knife,
where same is directed into fractured material at a fracturing point
for faster and more effective separation of phosphor powder and/or
dust from fractured material.
5. A digester system in accordance with claim 1 constructed with
a two stage filter apparatus where a first stage filter media is
coated with TEFLON or other slippery material enabling said first
stage filter media the ability to resist filter plugging by dust
particulate being drawn by a suction device mounted behind filter
arrangement; where a second stage filter media is arranged and constructed
with iodine impregnated carbon granuals of varying sizes for adsorption
of mercury vapors from gases being drawn through said first and
second stage filters.
6. A digester system in accordance with claim 5 constructed to
pneumatically transport classified materials exiting from each collection
hopper located directly under the screen dram through hoses having
varying gas velocities and pressures passing through a suction device,
whereas hoses being attached at one end to each bottom of the collection
hoppers and at the other end to a top of final collection chambers,
said collection chambers each having an inlet and outlet at the
top where gas at the outlet is drawn through said two stage filter
apparatus by a suction device whereby classified material is released
from air stream as same enters larger volume collection chambers
relative to hoses for final depositing.
Description BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the crushing or digestion of used
fluorescent lamps. More specifically, the present invention relates
to a combined crushing system whereby the various components, combined
in creating lamps, are crushed, cleaned and classified using one
mechanical motion. Further cleaning is achieved with the addition
of an air knife. Due to simplify, this invention can be made small
enough to function easily as a portable or mobile unit. A deflate
distinction is made between the separated components into clean
glass, clean metal ends and mercury rich phosphor powder.
2. Discussion of the Prior Art
Fluorescent lamps have long been recognized as an efficient lighting
source. They have been equally recognized as a difficult waste to
dispose of due to the presence of metallic mercury and mercury vapor
inside the lamps for operational purposes.
Due to the bulky, fragile nature of fluorescent lamps, it becomes
readily evident that conventional crushing merely to reduce the
volume, or partial seperation techniques after crushing do not sufficiently
deal with costly and/or potentially hazardous problems of handling
lamps during storage, transportation to a recycling facility and/or
disposal or recycling options of the end waste streams generated
by partial seperation techniques.
Following is a study of these issues . . . crushing, classification
of lamp components during processing and mobile use of this technology
relative to this industry:
U.S. Pat. No. 2185352 issued Jan. 2 1940 to C. F. Peters discloses
a foot operated hammer designed to impact a bottle in an inclined
chute; thereby breaking it and permitting the fractured pieces to
fall into a collection receptacle.
U.S. Pat. No. 2558255 issued Jun. 26 1951 to N. E. Johnson et
al. discloses a remote control motor driven glass fracturing apparatus.
U.S. Pat. No. 3363756 issued Nov. 21 1967 to D. J. Morgenson
discloses a horizontal high speed rotating hammer blade where bottles
are dropped through chute and struck as much as 60 times for each
second it remains in the contact zone.
U.S. Pat. No. 3655138 issued Apr. 11 1972 to G. A. Luscombe
discloses a plurality or ratating hammer blades where deflecting
blades are arranged to enhance distribution of fractured glass after
impact.
U.S. Pat. No. 3889886 issued Jun. 17 1975 to J. D. Spivey discloses
a waste bottle fractuing device where rate of entrance of bottles
is regulated via baffles which slow down entrance speed. Multiple
rotating arm blades, with baffles, prevent glass from being ejected
upwardly out of the crusher.
U.S. Pat. No. 2593657 issued Apr. 22 1952 to A. J. Coon et al.
discloses a reciprocating crusher designed to crush fluorescent
tubes. Coon attempts to contain free floating phosphor dust by venting
it "to the outer atmosphere wherupon it is safely dispersed
into space". Although Coon reduces the volume and trys to create
safe operating conditions, his efforts are grossly inadequate and
he does nothing in the way of filtering harmful emissions or classifying
lamp components into distinct gruoups i.e. glass, ends and powder.
Coon's process could be construed as mobile due to simplicity in
design but would not meet current safety levels.
U.S. Pat. No. 2620988 issued Dec. 9 1952 to E. H. Tellier discloses
continuous flushing of water at the fracturing zone. Dust is kept
from entering the air space however nothing is done to classify
fractured material. In addition, he has introduced water which is
now hazardous and the end result is worse than before processing.
U.S. Pat. No. 2628036 issued Feb. 10 1953 to J. B. Hall discloses
another fluorescent lamp disposal system where water is introduced
to control hazardous components. Lamps are pained lengthwise down
a tubular inlet; are progressively fractured into pieces by rotating
hammers. Some attempt is made to classify out metal end caps for
recycling by means of magnetic forces. This method is too cumbersome
to be mobile and classification with water in the system is messy.
U.S. Pat. No. 2866604 issued Dec. 30 1958 to J. B. Hall discloses
a fluorescent lamp disposal device where rotary arms impacts lamp.
Air drawn through lamp loading mechanism to attempt better vapor
control. Arrangement bathed in water during breaking,
U.S. Pat. No. 3913849 issued Oct. 21 1975 to I. M. Atanasoff
et al. discloses a fluorescent lamp digester or crusher. Mercury
and other fluorescent materials, have not been separated sufficiently
from the supporting and confining materials, i.e. glass to allow
safe handling. His system is designed to mount on top a barrel with
a downward draft drawn through a filter arrangement and out removing
mercury vapor and phosphor powder. No real attempt to classify.
U.S. Pat. No. 5092527 issued Mar. 3 1992 to T. J. Perry et al.
discloses a digesting system for disposal and seperation of component
materials using a series of countercurrent air streams. The system
is operated under negative air pressure to control and capture hazardous
vapors and dust. Lamps are inserted into a tubular opening where
impact with a rotary blade and seperation begin. Perry's system
is too bulky to be mobile and he does not classify component materials
enough. Glass and metal ends are deposited in two of three cyclone
chambers. The third chamber is a bag house for vapor and dust collection.
Air speeds are high around 6000 to 7500 feet per second making
vapor containment difficult. Crushing is seperate from seperation.
All seperation is done via air flow in the cyclones. Seperated component
materials are dropped down through the cyclones into a large holding
tank No good classification for recycling options once process is
completed.
Consequently, the need still exists for a method and means that
is economical, convenient and effective in treating or digesting
used lamps that crushes, deans and classifies materials but is small
enough to be operated as an economical mobile system.
OBJECTS OF THE INVENTION
It is an object of the present invention, therefore, to provide
an apparatus for treating used fluorescent tubes that effectively
classifies mercury rich phosphor powder, clean glass particulate
and clean metal end-caps into three seperate distinct classifications
by a dry rotating drum screening method.
It is a further object of the invention to provide a method and
means for treating used fluorescent lamps that could be made small
enough to be considered mobile or portable and thereby enabling
the invention to be taken from location to location thereby reducing
the regulatory restrictions and fluorescent lamp handling costs
currently incurred by all previous technologies.
It is a still further object of the invention to provide a method
and means for crushing, cleaning and classifying fluorescent lamp
material components all in a single motion.
It is a still further object of the invention to provide a method
and means for faster, better cleaning action by the introduction
of an air knife during processing.
It is a still further object of the invention to provide a method
and means for cleaning crushed material components using a friction
media during processing.
It is a still further object of the invention to provide a method
and means for crushing fluorescent lamps and fiction media via a
crusher fan which fractures and circulates fractured material back
through crusher fan for added turbulance and cleaning action during
processing.
It is a stir further object of the invention to provide a method
and means for containing phosphor powders by a TEFLON coated filter
media.
Other objects and advantages of the invention will become evident
from reference to the accompanying drawings and description.
BRIEF DESCRIPTION OF THE INVENTION
It has been found by the present inventor that a very good crushing,
cleaning and classification of material components utilized in construction
of fluorescent lamps can be made for used lamps to facilitate recycling
efforts by the process disclosed. Once the intact or previously
fractured lamp is inserted into the device, it impacts the crusher
fan which fractures and circulates fractured material through crusher
fan continuously until replaced by the addition of new fluorescent
lamp material through the feed tube entrance. The crusher fan is
mounted deep inside a tumbler screen. As fractured material is drawn
through crusher fan, it is being tumbled in the dram tumbler screen
where any phosphor powders fall through into a powder collection
hopper for exiting out of the process into sealed chamber. Bigger
glass and metal end particulate remain inside tumbler screen and
continue to act as friction media for any new fractured material.
Tumbler screen is a two stage screen with smaller hole opennings
at the bottom half of the screen drum and larger hole opennings
at the top half of screen drum facilitating clean glass particulate
seperation from tumbling process, for final exiting and collection
outside process. Metal ends remain in tumbler screen due to their
larger relative size and eventually exit tumbler screen through
the mouth openning of the tumbler drum into its respective hopper
for exiting outside the process into its final collection chamber.
An air knife is added being directed at fractured material inside
tumbler screen to further enhance powder seperation from fractured
material during tumbling. Mercury rich powder and clean glass are
air lifted into their respective collection chambers. The entire
process is operated under negative air pressure insuring the mercury
gas be drawn through charcoal filter arrangement where it is retained
until saturated by the gas.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an overall partially broken away side view of the apparatus
of the invention.
FIG. 2 is an enlarged broken away front view of the crusher fan
and feed tube entrance relative to the crusher
FIG. 3 is a broken away side view of crusher fan inside drum tumbler
screen where crushing, cleaning and classifying actually takes place.
FIG. 4 is an overall reduced view of the main apparatus of the
invention to show entrances and exits to the main processing chamber.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows diagrammatically a side elevation of a partially broken
away depiction of the fluorescent lamp treatment apparatus of the
invention in which the entire apparatus 32 33 and 34 are coordinated
to provide a very superior crushing, cleaning and classification
of the basic lamp material components. An initial feed tube is provided
2 with a fracturing and first stage cleaning device or means, hereinafter
called a rotating crusher fan 9 is fixed to drum base plate 22
and mounted inside a screen drum 40 device or means; the screen
drum 40 is fixed to an axle 42 FIG. 3 and powered by a motor 11
FIG. 1. The rotating crusher fan is positioned to strike the end
of a fluorescent lamp 1 that is extended or passed progressively
down the feed tube 2. The feed tube 2 is shown shorter than the
fluorescent lamp to better show the fluorescent lamp 1. However,
it is desirable for the feed tube 2 to be longer than the fluorescent
lamp so that, if the lamp implodes when impacting crusher fan 9
any toxic gas or flying glass will be contained within the feed
tube and sucked into apparatus rather than escape into the environment.
Negative air pressure is drawn inward from outside feed tube 35
as outside air passes between the lamp as the lamp passes down the
feed tube.
The rotating crusher fan 9 is preferably rotated, as shown in FIG.
2 counterclockwise so that the lamp is struck downwardly against
scissor edge of the feed tube 7 progressively fracturing off small
pieces of the lamp which at the same time are drawn through the
crusher fan 9 and forced upward in a circular fashion and recirculated
back through the crusher fan 9 to be broken into still smaller pieces.
A minimum of one blade to a mazimum of 16 blades can be used on
the crusher fan 9 as shown in FIG. 2 where leading edge 36 of fan
blade is sharpened to an edge that closesly resembles a scissor
edge where the trailing edge 37 is such that fractured material
impacting the leading edge is pushed past trailing edge creating
a flow of fractured material through crusher fan 9 up through friction
media 10. A side view of the crusher fan 9 as seen in FIG. 3 illustrates
the relationship between leading edge 36 and trailing edge 37.
In addition, the rotating screen tumbler drum 40 as seen in FIG.
1 is rotating a minimum of 40 revolutions per minute (rpms) to a
maximum of 70 rpms thereby forcing the stream of fractured material
10 which, in this case acts as friction media, continues recirculating
through crusher fan 9 and intersects a stream of tumbling fractured
material 6 further facilitating cleaning of fractured material 6
before exiting rotating screen tumbler dram 40. The impact of both
streams intersecting each other causes the toxic dust particulates
coating the inside of the fluorescent lamp to be blasted loose from
inside surface of fractured glass. Small dust particulates, after
jarring loose, become entrained in air stream within the apparatus
34. Air stream or flow which initially passes down feed tube alongside
fluorescent lamp 35 into tumbling chamber 40 and progresses through
powder hopper 26 and glass hopper 27. Both hoppers serve as exhaust
for apparatus 34. A vacuum or suction is applied to exhaust tubes
26 and 27 from a suction or draft device at the end of entire apparatus
32 in this case through two suction devices 18 and 19 with a minimum
air flow rate of 100 cubic feet per minute (cfm) and a minimum of
100 inches of water lift each up to a maximum air flow rate of 175
cfm and 100 inches of water lift each. Minimum combined suction
of 200 cfm; maximum combined suction of 350 cfm.
Below rotating tumbler screen 40 as seen in FIG. 1 two hoppers
26 and 27 are positioned. 26 collects free dust and mercury rich
phosphor powder 8 as rotating screen 41 as depicted in FIG. 3 sifts
out fine particulate through 1/16 inch to 1/8 inch openings where
gravity forces powder 8 downward to exhaust opening FIG. 4 opening
26. A hose 21 fixes to powder hopper exit tube 26 FIG. 1 and FIG.
4 and is air lifted into glass exchange chamber 13 as seen in FIG.
1 where powder and small glass particulate entering chamber are
further refined or seperated due primarily to a 90 degree turn in
gas direction created by suction device mounted to powder collection
chamber 32 where suction is drawn through three inch hose 20 where
distance between hose 21 entrance into glass exchange chamber 13
is located 23/8 inches from powder exit openning 29. Refined powder
travels inside hose 20 through powder suction chamber entrance 30
of powder suction chamber 32 to final resting place 15 at bottom
of powder collection chamber. Glass particulate, after seperation
with powder particulate, upon entering glass exchange chamber 13
is exited through glass collection chamber entrance 12 where a minimum
openning of three inches to a maximum openning of 75/8 diameter
hole size, depending on air flow, is needed. The diameter in any
case of glass exchange chamber 13 is eight inches. Any cleaned and
classified glass exiting tumbler screen 40 travels through hose
24 into glass exchange chamber 13 exiting chamber through entrance
12 to clean glass collection point 14. Any ambient dust being drawn
through hose 24 is seperated in glass exchange chamber 13 and drawn
through glass exchange chamber exit 29 through hose 20 with entrance
into powder collection chamber 212. Upon entrance of ambient fine
dust into powder collection chamber, suction device 18 draws mercury
rich vapor and phosphor dust gas through 0.3 micron openning TEFLON
coated first stage filter media 16 where mercury vapor and other
gases penetrate, but dust particulate gather on TEFLON coated first
stage filter 16 and slide off said filter media after sufficient
mass of dust accumulates due to gravity and viberation. Hence this
first stage filter media resists plugging and lasts up to five times
longer than none TEFLON coated filter media. The mercury vapor and
other gases are immediately drawn through the second stage filter,
in this case located inside first stage filter media 16 and are
collected in two to five pounds of iodine activated carbon which
adsorbes up to 18% of its weight in mercury vapor before dean gases
are exited outside process 17. Any free floating fine dust that
has not yet settled in powder collection chamber 32 is drawn through
powder chamber exit 31 due to suction device 19 and blown along
with other gases and mercury vapor through hose 25. Hose 25 connects
to air knife 23 where three 1/2 inch holes and two 1/4 inch holes
are aimed at tumbling media 6 aiding in speed of powder seperation
from fractured media.
The openning size of 28 and 2 are such that negative pressure is
created at both opennings 39 and 35 even with the introduction of
an air knife 23. Metal end-caps located in fractured material 6
as seen in FIG. 1 continue to fill tumbler screen 40 until exiting
mouth of tumbler screen 3 into metal end-cap hopper 28 and exiting
out the process at 38.
It should be understood that although the present invention has
been described at some length and in considerable detail and with
some particularity with regard to several embodiments in connection
with the accompanying figures and description, all such description
and showing is to be considered as illustrative only and the invention
is not intended to be narrowly interpreted in connection therewith
or limited to any such particulars or embodiments, but should be
interpreted broadly within the scope of the delineation of the invention
set forth in the accompanying claims thereby to effectively encompass
the intended scope of the invention. |