Note: Descriptions are shown in the official language in which they were submitted.
3~655 ~
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BACKGROUND OF THE INVEI~TION
The present invention relates gènerally to incin-
erators, and more particularly is directed to an incineration
system including one or more portable incinerators in com~in-
ation with non-portable air pollution control equipment
especially suited for the recovery of valuable metals, copper,
etc. from electrical and other scrap material.
It is now usual practice in most political subdivi-
sions to require the installation o suitable mechanical
equipment for control of air pollutants resulting from the
încineration of combustible solids and liquid. Air pollu~ion
control equipment of known types have included afterburners,-
settling chambers, scrubbers, electrostatic cleaners, spray
chambers, baghouses and the like. A wide variety of more or
less sophisticated or specialized equipment has been developed
by prior workers in the art and such equipment is presently
available to clean the effluent air from numerous polluting
activities such as various industrial processes and inciner-
ation. In the case of permanent installations that are
permanently fixed in location, pollution control equipment
and systems can be designed and installed in accordance with
known practice to provide satisfactory operating installations
of suitable effectiveness and efficiency to comply with the
requirements of known standards such as air pollution control
ordinances promulgated and approved by numerous municipalities
and states, and the federal government.
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Problems have arisen in certain situations where,
due to the nature and composition of the material to be
burned, such materials cannot be conveniently placed within
fixed incineration equipment. Combustibles such as the
insulation covering scrap wire and the fibrous materials of
printed circuit boards pose a unique incineration problem
because of material handling difficulties. Such scrap wire
normally is cumbersome, unwieldly and generally uneconomical
to transport to a fixed incinerator. It is necessary and
desirable, however, ~o remove the combustible insulation from
the wire to reclaim the wire. One solution to such a problem
has been described in detail in Spitz Patent No. 3,076,421
which patent is assigned to the assignee of the present ap-
plication. In Patent No. 3,076,421, a novel process for
handling scrap wire has been disclosed wherein a portable,
conical, shell type incinerator was moved by crane over a pile
of scrap wire for incineration purposes rather than the more
conventional method o transporting the combustible material
to a fixed incineration plant.
An afterburner for pollution control was provided
as an integral part of the portable incinerator, supplied
with fuel gas through a flexible tube. This contributed a
substantial amount of weight to the unit and also added to
its overall height. This present invention with a separate r
fixed afterburner, allows a wide choice of pollution control
and heat recovery processes and equipment. The present inven-
tion also considerably reduces the height and weight of the
portable primary combustion chamber. Additionally, it elimin-
ates the need for flexible fuel connections and permits the
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~L3~655
use of any fuel, gas, oil or even pulverized coal in the after-
burner. With a waste heat boiler or other device, heat from
the afterburner, which is wasted in the process o~ Patent
No. 3,076,421, can be reclaimed. The portable part of the
system, the primary combustion chamber, which receives the
greatest wear, is considerably simplified, and is economical
to repair or replace.
SUMMARY OF THE INVENTION
The present invention relates generally to the field
of air pollution control equipment and more particularly is
directed to an apparatus and method for the recovery of valu-
able metals and copper from electrical and other scrap mater-
ials.
The present invention seeks to ovèrcome the diffi-
culties experienced by prior workers in the art when attempt-
ing to utilize satisfactory air pollution control measures
to control the effluent from portable incinerators. In ac-
cordance with the teachings of the present invention, portable
incinerators are employed in conjunction with a pollution
control system wherein the air pollution control equipment
has been designed and arranged in a permanent mannerO The
air pollution control equipment i9 connected to duct work,
which may be pssitioned below grade. A plurality of inciner-
ator inlets are provided in the duct to accommodate one or -
more portable incinerators. The incinerators are designed for
movement to the inlets to thereby direct polluted gases through
the inlets and into the air pollution control system.
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In a preferred embodiment, an und~rground duct
system is permanently installed and at the inlet end, the
duct system includes one or more inlets in spaced locations.
~he remote end of the underground duct terminates in the
fixed air pollution control equipment for cleaniny the efflu-
ent gases from the incinerators prior to exhaust to atmosphere.
Each underground duct inlet opening is provided with
a vertical, hollow standpipe which has its interior conduit
or channel in communication with the inlet whereby the stand-
pipe serves to elevate the effective inlet opening to a loca-
tion that is spaced above the ground. Thus, gases of combus-
tion from within the portable incinerator must first travel
downwardly through the standpipe prior to entrance into the
underground duct system. In practice, the standpipe prefer-
ably may be fabricated of self-standing construction, without
permanent interconnection to the duct system, to prevent aamage
when in use.
In order to use the pollution controlled incinera-
tion system of the present invention, the combustible material
such as scrap wire, printed circuit hoards or other material
to be burned or processed is piled about the standpipe by
utilizing conventional equipment such as bulldozers, cranes,
etc. ~fter moving the matérials to the standpipe location,
a portable incînerator of the type that is fabricatea to an
inverted, conical configuration is applied over the material
and over the standpipe. The peripheral junction between the
bottom edge of the incinerator shell and the ground can be
covered with dirt or other materials to provide a peripheral
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seam that is substantially air tight. Small adjustable doors
are provided around the base of the primary combustion chamber
so that the amount of combustion air entering can be controlled.
As set forth in Spitz Patent No. 3,076,421, the amount of com-
bustion air should be sufficient ~o support combustion at a
relatively slow rate. In this manner, combustion temperatures
are minimized as the wire insulation or other combustible
material is burned, and, in the case of copper wire, oxidation
of the copper during incineration is also minimized.
It is noteworthy that the present system provides
a portable primary combus~ion chamber having no flue connec-
tion and no air pollution control equipment directly associ-
ated therewith.
The underground duct receives gases of combustion
and partially oxidized organic vapors from within the primary
combustion chamber through the standpipe and the duct inlet.
The duct directs the gases and vapors to a permanent pollution
control system. The pollution control system includes an
afterburner chamber wherein the effluent from the primary com-
bustion chamber is completely oxidized and wherein a portion
of the required heat is supplied. Exhaust gases from the
underground duct enter the bottom of the afterburner of the
pollution control system and travel upwardly therethrough.
This chamber includes one or more burners and a restrictive
orifice to initiate the air cleaning process. The partially
cleaned gases travel from the afterburner across a horizontal
stack section and thence downwardly through the cooling chamber.
The cooling chamber serves as a water spray cooling chamber
and may be equipped with a water spray cooling system for air
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cleaning and gas cooling purposes. Exhaust from the cooling
chamber, if sufficiently cleaned of pollutants within the
afterburner chamber and cooling cham~er can be exhausted to
atmosphere. If the effluent gases are still below code stan- -
dards for atmospheric discharge after traveling through the
water spray cooling chamber, a baghouse can be installed in
the system in well known manner. In the event the material
being incinerated produces chlorides, it is desirable to
employ a pre-coated baghouse of known design. ~ waste heat
reclamation unit may be incorporated into the top of the
afterburner or in the duct leading to the cooling chamber.
An induced draft fan is positioned at the end of the pollu- -
tion control system and acts to provi~e a positive induced
draft throughout in accordance with known practice.
It is therefore an object of the present invention
to provide an improved, pollution controlled incineration
system of the type set forth.
It is another object o~ the present invention to
provide a novel pollution controlled incineration system com- -
prising a portable incinerator or primary combustion chamber
and means to conduct exhaust gases from the incinerator to a
fixed pollution control system.
It is another object of the present invention to
provide a pollution controlled incineration system comprising
a portable, conical, invertPd incinerator shell and means to
exhaust gases ~ro~ the shell without utilizing an incinerator
stack.
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1~3~655
,
It is another object of the present invention to
provide a novel pollution controlled incineration system com-
prising an underground duct system, one or-more standpipe
equipped inlets to the system and a single, remote duct ex-
haust comprising permanently installed, pollution control
apparatus.
It is another object of the present invention to
provide a novel pollution controlled incineration system com-
prising an underground duct system, a standpipe inlet which
spaces an inlet to the duct above ground level, a portable
incinerator removably located over the standpipe and permanent-
ly installed pollution control apparatus receiving exhaust
gases from within the portable incinerator through the stand-
pipe inlet.
It is another object of the present invention to
provide a novel pollution controlled incineration system com-
prising duct means, standpipe means communicating with the
duct means, portable incinerating means overfitting the
standpipe means and pollution control means receiving exhaust
gases from the incinerator means through the standpipe means
and the duct means.
It is another object of the present invention to
provide a method of controlling polluted air comprising the
steps of incinerating :scrap material within a portable incin-
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~3;~6S~i
erator and creating gaseous pollutants, directing the pollut-
ants downwardly through a standpipe into a duct system, lead-
ing the pollutants through the duct system to a pollution
control apparatus, directing the polluted gases upwardly and
downwardly through the pollution control apparatus, cleaning
the polluted gases within the pollution control apparatus
and then exhausting the effluent in clean condition.
It is another object of the present invention to
provide a novel pollution controlled incineration system that
is partly portable and partly fixed in construction, simple
in design and trouble-free when in operation.
Other objects and a fuller understanding of the in-
vention will be had by referring to the following description
and claims of a preferred embodiment thereof, taken in conjunc- -
tion as illustrated with the accompanying drawings, wherein
like reference characters refer to similar parts throughout
the several views and in which:
BRIEF DESCRIPTION OF THE DRAWI~Gg
Fig. 1 is a schematic elevational view showing the
genera- arrangement of the operating elements of the inven-
tion, with portions thereof partly broken away to expose de- -
tails of interior construction.
Fig. 2 is an enlarged, perspective view of a port-
able incinerator constructed in accordance with the teachings
of the present invention.
. Fig. 3 is an enlarged, perspective view showing one
embodiment of a standpipe construction.
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DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION
Although specific terms are used in the following
description for the sake of clarity, these terms are intended
to refer only to the particular structure of the invention
selected for illustration in the drawings and are not intended
to define or limit the scope of the invention.
Referring now to the drawings, there is shown in
Fig. 1 a pollution controlled incineration system generally
designated as 10 which comprises in part a duct system 12
suitable to remove pollution laden gases of combustion from
the incinerator 14 in the manner hereinafter more fully set
forth. In the preferred embodiment, the duct system 12 is
positioned below ground level 104 to prevent damage, facilitate
use and to minimize space requirements.
As illustrated, the duct system 12 is positioned
below grade level 104 in a manner not to inter~ere with the
normal operation of an incinerator plant wherein mechanical
equipment (not shown~ such as bulldozers, can be utilized
to position and pile the loose material 44 to be burned, - ;
for example, insulation covered wire, against the outer peri-
phery o the standpipe 16. Of course, the construction of
the underground duct 12 should be designed of su~ficient
strength in well known manner to withstand the weight of the
mechanical equipment that may be imposed thereon. The duct
system 12 is fabricated to define an interior, elongated ,
continuous channel 60 of sufficient cross-sectional size to
conduct the gaseous pollutants (not illustrated) which are
generated by the combustion o the w~e materials 44 from
the portable incinerator or primary combustion chamber 14 to
the pollution control system 18.
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Inasmuch as these materials 44 will be incinerated
within the interior space 106 enclosed by the portable incin-
erator shell 36, the pollutant laden gases will be elevated
in temperature by the combustion process. To prevent deterior-
ation of the duct system 12 as a result of high gas temperatures,
in the preferred embodiment, the duct system is lined with a
refractory material 58 of known composition suitable to with-
stand the effects of elevated temperatures and gases of combus-
tion. The duct 12 comprises one or more gas inlet openings-
56 whereby one or more portable incinerators 14 can be accom-
modated at the same time to direct the gaseous effluent from
the incinerators to the pollution control system 18. The duct
system 12 terminates in a remote end 108 which includes a sin-
gle outlet 62 through which pollutant laden gases from the -
incinerators 14 exit from the underground duct 12 to enter
the pollution control system 18 prior to exhaust to atmosphere
through the exhaust duct 28~
As illustrated in Figs. 1 and 2, the portablc com-
bustion chamber 14 is fabricated of plate steel to an inverted,
hollow, conical configuration which terminates up~ardly in a
closed apex or top 38 and which terminates downwardly in an
open circular base which is defined by the bottom periphery 40
of the incinerator shell 36. A structural frame 30 is welded
or otherwise fixed to portions of the conical shell 36 in well
kno~m manner to provide structural integrity and also to pre-
vent distortion when the incinerator 14 is used or transported.
The members comprising the incinerator frame 30 convexge up-
wardly-and are welded or otherwise affixed to the upright
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supports 110 in a sturdy manner. The supports 110 upwardl~
carry a transverse web 32 which furnishes a convenient place
of attachment for the hook or cable or clamshell bucket of a
crane (not shown) for primary chamber transport. The crane
can also be used to pile material around the standpipe 16 and
to unload the residual material after incineration is complete.
The upper supports 110 and the transverse web 32 define a
space 34 between the structural members and the incinerator
shell 36 which provides sufficient clearance whereby the hook,
clamshell bucket or other suitable member may be inserted when
grasping the web or yoke 32 for primary combustion chamber
transport purposes. In usej a crane or similar device (not
shown) can be utilized to lift and transport the portable in-
cinerator 14 by engaging the incinerator at the upper web 32
thereof during the lifting and transporting operations in well
known manner. If desired, the primary combustion chamber shell
36 may be changed from conical to cylindrical near the bottom
thereof to form a generally cylindrical section 114 comprising
a short, vertical side wall 116 immediately above the shell
bottom periphery 40. In practice, a 6 inch by 6 inch angle
formed to a circular configuration may be used to form the
bottom of the conical, portable shell, thereby reinforcing it
structurally. In use, dirt 42 or similar loose material may
be piled against the vertical side wall 116 to limit the amount
of combustion air that can enter the interior 106 of the con-
ical incinerator shell 36 through the junction between the
bottom of the shell and the ground 104, thereby limiting the
rate sf combustion and the internal temperatures generated
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~3~655
during the combustion process. If necessary or for operating
efficiency, desirable, one or more combustion air openings
76 can be provided in the shell 36 to allow additional air
for combustion purposes to enter the interior 106 of the
portable incinerator 14. Initial ignition can also be accom-
plished through an opening 76. In the preferred embodiment,
the shell 36 is unlined, whereby some of the heat of combus-
tion can radiate and escape directly through the shell. This
construction also aids in reducing internal temperatures
within the incinerator during combustion. ~owever, for some
uses, it may be desirable to use lightweight insulation on the
inside of the shell.
As above set forth, the duct system 12 may include a
plurality of inlet openings 56 which are spaced apart a dis-
tance greater than the diameter o~ an incinerator bottom whereby
a-single r permanently installed pollution control system 18
may be utilized to treat the effluent from a plurality of por-
table primary combustion chambers 14~ The duct system 12 may
include inlets located in one or more branches which feed the
single duct outle~, 62, or may include a plurality of inlets
spaced along a unitary branch. Each branch comprises one or
more inlet openings 56, each opening being equipped with a
standpipe 16 for initial control o~ pollutant laden gases.
Each standpipe extends in height a suitable distance to provide
for flow of gases resulting from combustion within the incin-
erator downwardly therethrough. A standpipe hei~ht of approxi-
mately six to eight feet has been found generally suitable for
this purpose.
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As best seen in Fig. 3, each standpipe 16 is fabri-
cated to a hollow, cylindrical configuration and preferably
is fabricated of cast heat resistant allow which is formed
to the desired configuration in manner well known to those
skilled in the art. A standpipe diameter of between one to
three feet has generally been found satisfactory for the pur-
pose. The standpipe bottom may be affixed directly to the
duct inlet opening 56 in a substantially leak-free junction
to assure that the gases will enter the duct system 12 through
the standpipe upper end or inlet 48 and then flow downwardly
therethrough to the standpipe outlet 50 which is in communica~
tion with the underground duct inlet 56.
In use, the material to be burned, such as insulation
covered wire 44 or other combustible material is piled or
otherwise positioned about the outex periphery of the stand-
pipe 16 in well known manner such as by employing a bulldozer.
After the material to be burned is piled about the outer per-
iphery of the standpipe 16, a crane or other device then trans-
ports and lowers the portable incinerator 14 directly over
the standpipe 16 and the piled material 44. After the inciner
ator has been thus positioned, dirt 42 is placed about the
bottom periphery of the incinerator to limit the amount of air
that can enter the interior 106 of the portable incinerator 14.
To prevent damage to the system which may be occa-
sioned by the bulldozer or other equipment (not shown) striking
the standpipe 16 or also to permit the easy removal of stand-
pipes 16 from areas or branches of the duct system 12 that
are not in use, in a preferred embodiment as illustrated in
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Fig. 3, the standpipe 16 may also be fabricated to be gener-
ally portable in nature. In the embodiment illustrated in
Fig. 3, the exhaust tube 46 of the standpipe 16 terminates
downwardly in a relatively heavy supporting base 52 which
preferably is also fabricated of heat resisting allow and which
may extend in diameter a length of approximately seven feet
to provide sufficient stability. The exhaust tube 45 can be
secured to the support 52 in a well known manner such as by
employing a peripherally welded junction 54 and the supporting
base is provided with an opening therethrough equal to the
standpipe interior diameter. By utilizing the support 52
which is relatively heavy because of its diameter and thick-
ness, most lateral forces directed against the exhaust tube
46 will be resisted by the welght o the base 52. Ho~Jever,
should the lateral forces directed against the exhaust tube 46
be unusually great, such as when accidentally struck by a bull-
dozer r then because of the unitary, portable construction, the
entire standpipe 16 comprising the exhaust tube 46 and the
support base 52 will be moved from the resting place above
the duct opening 56 without damage to any of the par~s. In
this manner, such lateral forces can be dissipated in movement
and in friction without damage. In the event of such a happen-
ing, prior-to utilizing the incinexator 14, the standpipe
bottom opening 50 should be re-registered over the duct opening
56 to assure unrestricted 10w of pollutant laden gases into
the duct system 12. I desired, the duct openings 56 may be
equipped with steel bars or grills both as a saety precaution
and also to prevent the entrance of large foreign materials
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into the underground duct system 12.
Referring now to Fig. 1, a single air pollution
control system 18 is illustrated to receive.pollutant laden
gases from the interior 106 of one or more portable inciner-
ators 14. Gases of combustion from within the incinerators
travel downwardly through the standpipe 16, through the
underground duct inlet opening 56, horizontally through the
duct 12 and thPn upwardly through the single duct outlet open-
ing 62 into the interior o the control system afterburner
20 in a path indicated generally by the arrows 118, 120 and
122.
The afterburner 20 of the pollution control system
18 comprises a vertical, tubular structure through which the
pollutant gases upwardly flow. Preferably, the interior of
the afterburner 20 is refractory lined to prevent damage from
the hot gases resulting from combustion within the interior
of the portable incinverators 14. As illustrated, the refrac-
tory lining 68 interiorly covers and protects the afterburner
steel shell 66. A turbulence ring 70 projects radially in-
wardly and may be integrally formed of refractory lining
material. As illustrated, the ring 70 defines a constricted
orifice 124 through which the gases of combustion upwardly
flow as indicated by the arrows 126. The turbulence ring 70
serves to restrict the flow of gases through the orifice 124
to increase turbulence and to assure a be~ter mixing of gases
as the combustion gases travel through the afterburner 20.
Two or more burners are angularly positioned near the bottom
of the-afterburner 20 to aid in the air pollution control func-
tion of the system 18. The burners 72, 74 may be oil fired
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or gas fired of well known desiyn for the purpose, such as
the duel fuel burners manufactured and sold by the North
American Manufacturing Co., Cleveland, Ohio.
The choke ring or turbulence ring 70 acts to pre-
vent stratification of burner gases and combustion gases when
traveling upwardly in the afterburner 20. The orifice 124
mixes the burner gases and combustion gases by creating tur-
bulence at the ring 70 to enhance combustion within the after-
burner 20. The upper section of the afterburner chamber 20
may have a waste heat reclaimer incorporated into its design
whereby a substantial amount of heat from both the burning of
the insulation and other materials and from the afterburner
fuel can be recovered. It is anticipated that once the after-
~urner becomes sufficiently hot, the process will be self-
sustaining and will re~uire no additional fuel.
The chamber 22 is preerably fabricated similarly
to the afterburner 20 and includes an outer steel shell 80 which
is interiorly peripherally protected by a full refractory
lining 82 in known manner. The chamber 22 is designed as a
~7ater spray cooling chambex and is upwardly equipped with a
spray nozzle 88 which feeds a liquid spray interiorly for gas
cooling purposes and for removal of large particulate matter.
The interior of the chamber 22 includes a bottom positioned
drain 86 to drain excess li~uid and entrained particles there-
through to a suitable disposal (not shown). If desired, a
clean-out 84 may be positioned near the bottom of the chamber
22 in conventional manner to permit entry into the interior
of the steel shell 80 for inspection, interior cleaning pur-
poses, etc. The cooled gases flow downwardly through the
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chamber 22 and through the spray chamber outlet 90 as indicated
by the arro~7 128. The cooled and partially cleaned gases flow
through the outlet 90, through the transition duct 130 and into
the inlet 92 of a baghouse system 24 for further cleaning, if
necessary.
The baghouse 24 is conventional in design and com-
prises a usual enclosing shell 132 which terminates downwardly
in a receiving hopper 134 wherein particulate, solid matter is
directed. The baghouse 24 conventionally includes a hinged
access door 102 and a usual screw conveyor 94 including an air
lock or control-valve 96.
The combination of the burners 72, 74 positioned
within the afterburner 20, the action of the spray nozzle 88
within the spray chamber 22 and the equipment contained within
the baghouse 24 serve to adequately clean the polluted gases
generated in the combustion process within the interior of the
portable incinerator 14 to meet all presently known air pollu-
tion control standards. The pollution control system 18 is
fixed in construction and employs all necessary equipment and
controls xequired to clean the pollutants from the combustion
gases prior to discharge to atmosphere. Accordingly, even
though one or more portable incinerators 14 are employed in the
process and the portable incinerators do not themselves incor-
porate pollution control apparatus, the fixed pollution control
system 18 fully treats all of the gases of combustion to ade-
quately clean the polluted effluent from the incinerators.
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The cleaned gases (not shown)..upwardly exit from
the top of the baghouse 24 through a conventional poppet 98
and flow through the transition duct 100 to the inlet of
the fan 26, which is motor driven in conventional manner.
The cleaned air is then discharged to atmosphere through
the exhaust duct 28 as indicated by the arrow 136. The fan
or fans 26 serve as an induced draft fan apparatus to posi-
tively pull the gases of combustion from the within the incin-
erators 14 and through the system 10 in the direction indicated
by the arrows 118, 120, 122, 126, 128 and 136~ I.f desired
to aid in the gas cleaning process, the baghouse may be pre-
coated in known manner to remove chlorides and other pollutants
normally resulting from the combustion of certain plastics such-
as polyvinylchloride.
Although the invention has been described with a
certain degree of particularity, it is understood that the
present disclosure has been made only by way of example and
that numerous changes in the details of construction and
the combination and arrangement of parts may be resorted to
without departing from the Fpirit and scope of~the invention~
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