Note: Descriptions are shown in the official language in which they were submitted.
~, The Field of ~he Invention
20 1l The field of the present invention is in the melting,
refining and processing o~ ferrous and non-ferrous metals, with
~, or without a simultaneous alloying thereof with other metals and
with or without the introduction of other ingredients into the
molten metal to affect the composition or characteristics of the
end-product, and the field of the present invention is also in
the reduction of ores o metals.: ¦
~, .
.
~ i427C~
The field of the present invention is more particularly the
processing of metals and ores in such furnaces by supplying both
the heat required for melting the metal or its ore and for keeping
it molten and for supplying the reducing or oxidizing gas for the
processing of the metal by submerged internal-combustion burners
which discharge the hot products of combustion substantially below
the level of the melt or "melt-linel', thereby to agitate and stir
and circulate the melt within itself so as to achieve a uniform
composition and uniform characteristics throughout the finished
end-produce.
The term "internal combustion burner" as used herein means a
burner having a combustion chamber therein to which fuel and
combustion-supporting gas are supplied~ and in which internal-
combustion chamber the combustion takes place and is substantialLy
compl~ted, and from the discharge end o which burner the hot
products of combustion exit substantially below the level of the
melt. As shown by Figure 1, none of the interactîon between the
fuel and oxygen takes place below the bottom of the pool of molten
metal.
The fuel and the combustion-supporting-gas are supplied at a
pressure substantially higher than the static pressure of the melt
at the depth thereof at which the burner discharges the hot
products of co~bustion.
The word "oxygPn" as used hereinafter isintended to encompass
25 air as well as oxygen-enriched air and also oxygen alone and a
mixture of oxygen and an inert gas, and the word "melt" is intended
to encompass a pool of molten metal ~ld also a molten pool of an
ore thereof and also a pool of a mixture of molten metal and ore,
and the phrase "metal source" is intended to encompass metallic
feed-material and also an ore of the metal as a feed material.
'.
., _~_
!" ~ oæ~ .
B _ f Summary of the Invention .
The present invention generally contemplates a fwrnace
including a melt-down section at one end, and a refining processing
section downstream thereof, preferably with a bridge-wall
S separating the two sections, such bridge-wall extending downwardly
from the roof o the furnace and extending into the melt to a
point substantially below the melt-level or "metal-line" so as to
prevent unmelted metal pieces or particles from passing from the
melt-down section into the refining or processing section.
A material-feed is disposed above the melt-down section and
a flue passageway extends through the upper portion o~ the bridge-
wall which is between the roof of the furnace and the metal-line,
and such flue-passsgeway extends into the end of the material-feed
~ tower (or other material-feed means) near or adjacent to themetal-
line in the melt-down se~tion, so that the hot products of
combustion which rise upwardly through the m~lten material in the
,; refining and processing section and accumulate in said section
. above the metal-line will pass through such flue-passageway (in
.. ~. the bridge-wallj into the material-feed section or what is also
;, 20 the pre-heating section, so that such hot gaseous products of
.. combustion will pass through such material-feed and pre-heating
section countercurrent to the movement of solid metal piece~ or
, particles and will pre-heat the same.
; The material-supply and pre-heating section may be in the
form of a flue tower, with downwardly-inclined cascading baffles
extending inwardly from the sides thereof ~as indicated in Figure
. 1), or such material-feed and pre-heating section or means may be
.~r~ a fluidized bed if the solid metal particles are su~ficiently
small so that the hot products of combustion passing therethrough
~i 30 will keep the bed fluidized and moving towards the m~tal-line in
the melt-down section, or such material-feed and pre-heating
section or means may be an inclined rotary tubular section in
which solid materials or particles will tumble and so eed or move
- 3 -
~ 542~
towards the metal-line in the melt-down section. The a~oremen-
tioned baffles in the tower-like or flue-like feed and pre-heating
section are used primarily where the material to be melted is in
the form o~ relatively small particles which can flow down through
~he staggered baffles. If the material to be melted is in the
form of relatively large pieces, the baffles (shown in Figure 1)
may be omitted.
A suitable number of generally uniformly distributed lance-
like internal-combustion burners are adjustably mounted in and
extend through the roof of the refining or processing section of
the furnace and are of sufficient length so that when they are
adjusted for their submerged position, a substantial length o the
burner will be submerged within the melt, and so that when they
are retracted they may discharge the products of combustion at a
point suitably above the metal-line, so as to meLt any previously
molten material which had solidified in the refining section
during a shut-down of the furnace-operation without the molten
metal having been first ~ully drawn off from the furnace.
One or more relatively short internal-combustion burners may
be non-adjustably mounted in and extend through the side-wall of
the melt-down section of the furnace at a point substantially below
the metal-line. Such side-wise mounted burners may have their
discharge ends or noses flush with the inner surface of the wall
in which they are mounted or such noses may be set back a slight
distance from such inner surface of the wall of the furnace.
While such side-mounted burners are removably mounted, they need
not be adjustable in relation to the furnace wall unless there is
need for projecting their noses a substantial distance into the
mel~ and for retracting their noses at times.
Such side-mounted burners melt the incoming solid materials
or particles thereof and help to keep the same m~lten~
A molten-metal overflow or discharge opening is proYided at
the metal line Ln a refining section o~ the furnace r preferably
~, ,.
_ ~
. ,
at the downstream end thereof, ~ollowed by a suitable spout if
continuous operation of thefurnace is desired. If the furnace is
to be operated batch-wise, then a tape-hole is provided in thewall
of the refining section of the furnace at or slightly below ~he
floow-level thereo, through which the batch o the ~inished melt
can be withdrawn;- such tap-hole being plugged or the next batch.
By providing the discharge-opening and the spout above the melt-
line or metal-line, molten metal may be drawn off by tilting the
furnace.
Brief descri~tion of the drawings
Figure 1 represents a somewhat schematic cross-sectional view
of a furnace representing an embodiment of the present inven~ion.
Figure 2 represents a vertical cross-cectional view on line
2-2 of Figure 1.
Figure 3 re~resents a top plan view of the furnace shown in
Figure 1.
Figure 4 represents a fragmentary horizontal cross-sectional
r view on line 4-4~of Figure 1.
Figure 5 represents a somewhat schematic longitudinal cross-
sectional view of an embodiment of the internal-conbustion burner.
Figure 6 represents a cross-sectional view on line 6-6 of
Figure 5.
Figure 7 represents a cross-sectional view on line 7-7 of
Figure 5.
Figure 8 represents a cross-sectional view on Line 8-8 of
Figure 5.
s Figure ~ represents a cross-sectional view on line 9-9 of
Figure 5.
Figure 10 represents a fragmentary cross-sectional view on
the circular line 10-10 on Figure 6;butshown in planardevelopment
Det _ ed description of the Invention
In the e~odiment illustrated by the drawings, the furnace
includes a mel~-down section 1 and a refining or processing
- 5 -
~ L54Z7C~
section 2 downstream thereof. The mel~-down section 1 and the
processing section 2 have, in common, an imperforate refractory
bottom or floor 3 (Figures 1 & 3). The melt-down section 1 has a
reractory end-wall 4 and side-walls 5-a and S-b. Refractory end
walls 6-a and 6-b at the upstream end of the processing section 2
extend from the side-walls 5-a & 5-b (respectively~ of the melt-
down section 1 to the refractory side-walls 7-a & 7-b of thc
processing section 2, and the refractory end-wall 8 at the down-
stream end of the processing section 2 ex~ends between the down-
stream ends of the side-walls 7-a & 7-b as indicated in Figures 1,
2, 3 ~ 4.
A bridge-wall 9 extends downwardly from the roof 10 o the
processing section 2, between the upstream end-walls 6-a & 6-b
thereof, to a point substantially below the metal-line 11, with
!: 15 the lower end 12 of the bridge-wall being sufficiently above the
floor 3 to permit the free flow of molten metal from the melt-down
; section 1 into the processing or refining section 2 (Figures 1 &
i; 2) and extends into the melt to a point sufficien~ly below thP
metal-line 11 (of sufficiently close to the fLoor 3 of the furnace)
as to prevent unmelted pieces or particles o metal from passing
from the melt-down section 1 into the refining section 2.
The roof 10 ~ay be arched as indicated in Figure 2 or it may
be flat.
The upstream end-walls 6-a & 6-b of the processing section 2
~ld the bridge-wall 9 are formed in direct continuation o each
other.
The material-feed ~nd pre-heating tower and flue 13 extends
upwardly from and may be formed in direct continuation of the end-
wall 4 and side-walls 5-a & 5-b o the melt-down section 1 ~Id the
end-walls 6-a & 6-b of the processing section ~ and the bridge-wall
9, as indicated in Figures 1, 2 & 3.
- 6 -
, I
S9LZ7~D
A flue opening 14 extends from the processing section 2 to
the material-feed and pre-heati.ng :flue 13 through the bridge-wall
9, from a point near the roof 10 in the processing section to a
~ point in the material-feed and pre-heating flue 13 which is near
5 ¦ the melt-line 11, so that the hot products of combustion which
accumulate in the procession section 2 (between the metal-line 11
and the roof 10) will flow into the bottom of the material-feed
and pre-heating 1ue 13 approximately at a point near where the
~ solid metal pieces or particles are delivered to the metal-line 11¦
10 ~ in the melt-down section 1, and so that the hot products of com-
¦ bustion w~ich so come through the flue passageway or opening 14will pass outwardly through the material-feed 13 counter-current
to the movement of the solid metal pieces or particles, so as to
pre-heat the same.
The lowermost metal pieces or particles in the material-feed
l; may be melted by the hot gases coming through the flue-passage 14
.~ plus the hot gases of combustion issuing from the internal-
. combustion burner or burners .in-the melt-down section 1 (described.~ hereinaftar).
Opposite downwardly inclined baffles 17 & 18 extend inwardly
from the opposite walls 19 & 20 of the material-feed and pre-
. heating tower and flue 13, in the manner indicatecL in Figure 1, so
: : as to cause the solid material to cascade down through the
; material-feed and pre-heating tower and flue 13 in such a way as
to maximize the exposure of the solid material pieces or particles
to the hot products o combustion rising upwardly through the
. ~ tower and flue 13.
A plurality of relatively long internal-combustion burners 21¦
(one embodiment of which is shown in Figure 5) extend downwardly
30 ~ through the roof 10 of the refining or processing section 2 of the
¦ furnace and are adjustably mounted thereto in genarally gas-tight
relation therewith by stuffing-gland~like colla-rs or means 22
schematically indica~ed in Figure 1.
- 7 -
~S~L~27
.
The burners 21 may be vertically adjusted and may be retracted
upwardly (as shown in Figure 1) so that they discharge the hot
products of combustion above the metal-line 11 and SQ tha~ they
may be extended downwardly and submerged in the melt, ~hereby to
discharge the hot products o combustion substantially below the
metal-line or in proximity to the floor of the furnace.
The burners 21 are retracted if it is desired to shut down
the furnace with molten material left therein, which wi~l solidify
during the shut-down period. When the furnace is started up again,
aft~r such shut-down period, the withdrawn burners 21 are started
up and made to fire or to discharge the hot products of combustion
above and in sufficient proximity to the upper surface o the
theretofore solidified material, gradually to melt the same, and
. ~ are then lowered into the molten material either in a single step
or gradually as the material is melted, until they reach their
fully submerged position shown in Figure 1.
Some of the burners 21 may be withdrawn and rendered inoper-
ative while others are submerged and operate, if less than all
: t'ne burners 21 will provide sufficient heat to keep the materials
molten and at a sufficien~ly high temperature for the refining,
alloying, compounding or other proces6ing of the melt.
One or several short side-mounted internal combustion burners
23 are extended through the side-wall or side-walls of the melt-
down section 1 of the furnace, substantially below the metal-line
11, as indicated in Figures 1 & 4 to cause the hot products of
combustion discharged from the burners 23 fi~st to melt the
. incoming feed of solid material or particles and then to keep the
; materials molten in the melt-down section 1 and also to contribute
to the hot products of combustion rising upwardly through the pre-
30 ¦ heating tower and flue 13. The submerged side-mounted burner or
burners 23 are provided only when the furnace is either operated
continuously without any shut-down while therP is molten metal
' -8-
^ ~15~Z'~
within the furnace above the l.evel o the side-mounted burners 23
or where the furnace is operated batch-wise with a complete with-
drawal of the molten material through th~ tap-hoLe 24 or where the
molten material is withdra~n through a tap-hole 24 to apoint below
5 the level of the side-mounted burners 23 if such withdrawal is for
the purpose of a shut-down.
The overflow-opening 15 in the downstream end-wall 8 of the
furnace is at a point which determines the location of the metal-
line 11 in the continuous operation of the furnace. The spout 16
is carried by and extends outwardly from the end-wall 8 o the
furnace to a sufficient distance so as to permit the metal flowing
. over ~he lip of the spout to be readily caught by a ladle, mold
. or other catchment vessel which may be used for receiving the
: finished molten metal.
For batch-wise operation, the metal out-flow-opening 15 may
~: be located substantially above the metal-line 11, and finished
molten metal may be drawn off through the opening 15 by tilting
: the ~urnace about a suitable transversely-extending horizontal
pivot or fulcrum beneath the floor of the furnace suitably located
therealong, so as to permit the upstream end of the furnace to be
raised (by a suitable hoist or hydraulic lift o the ~ike) in
relation to the downstream end of the urnace so as to tilt the
furnace at an angle suitable for such drawing off of ~inished
molten metal. The tilting pivot or fulcrum may be beneath the
steel structure supporting the bottom or floor 3 of the furnace
or the ~ilting pivot or fulcrum or may be located at a suitable
point substantially above the floor 3, but in such case the
pivotation would be provided by two opposite co-axial trunions
extending outwardly from the side-walls 7-a & 7-b (secured to the
steel frame of the furnace in which the refractory bottom and
walls are mount~d). If it is desired to tilt or rotate the furnace
fcr drawing off the finished lten metal, the material-feed or
_ 9 _
1 154270
pre-heating 1ue 13 would be materially shor~ened and the gases
discharged therefrom vented into a suitable hood beneath or
connected to a suitable chimney or stack.
When the material to be fed to the :Eurnace is in relatively
small pieces or particles, it may be fed to the furnace by means
of an inclined rotary-drum pre-heater, or if the particles are
sufficiently small and generally uniform the material may be fed i,
to the furnace ~hrough a fluidized bed of such particles. In each¦
~ case, the hot products of combustion rom the burners 21 & 23 pass~
10 ¦ through such rotary drum and through such fluidized bed.
The herein described metalur~ical furnace may also be used
for the processing of metals rom a direct-reduction of the ores
thereof and in continuation of such direct-reduction.
The feed-material may also be sponge-iron or pre-reduced iron
or other pre-reduced metals.
I may also effect the direct reduction of ores of metals, as,
for instance, iron ores, by feeding the iron ore through the
material-feed and pre-heating stack 13 or by feeding suitable
small-particle crushed ore or suitable size pellets of the ore to
the furnace, above the pool of molten iron, through a fluidized
bed or through an inclined rotary pre-heating retort.
The small particle ore of the suitable-size pellets may be
partly or substantially reduced in the fluidized bed, as, for
instance, to a reduction of 65 to 85% of Fe or to a reduction of
85 to 90% of Fe, whlch partly reduced ore is then fed to the pool I
of molten iron beneath the di~cha~ge end of the fluidized bed or
inclined rotary-drum where it is further reduced by the below-
mentioned reducing atmosphere, or the small-particle ore or
pellets o~ ore may be only pre-heated in the fluidized bed or in
30 1 the inclined rotary drum or reduced to a much lesser ex~end than
above mentioned, and the so pre-heated ore or lesser-reduced ore
! is then fed to the pool of molten iron beneath the discharge end
~1 10- 1,
1154Z70
~lof the fluidi~ed bed or inclined rotary drum where it is then
¦Ifurther reduced.
I may provide the reducing atmosphere by supplying air (or
l~other combustion-supporting gas) through the supplying-pipe 67 of
5 ¦~the internal combustion burners (21 and/or 23) at a rate which is
! sufficiently less than the stoichiometric quan~ity thereof in
relation ~o the fuel being fed ~o sald burners, so that the gases
issuing from the submerged discharge ends of the burners will be
generally reducing gases, while still supplying sufficient heat
needed for the reduction of the ore and/or for the fusion or
melting of the reduced material. The interaction be~ween the fuell
and oxygen of which the non-stoichiometric proportions thereof are¦
capable is substantially completed within the combustion-chamber
26 of the internal combustion burner shown in Figure 5.
I may also provide a reducing atmosphere by injecting into
the molten pool of metal or in the zone i~nedia~ely above the
metal-line thereof, additional gaseous fuel (or llquid fuel), with
~ or withou~ a concurrent supply of steam mixed therewith. The so
'r ~ produced reducing atmosphere may be used by itsel:E without the
aforementioned reducing gases from the internal-combustion burners~
or in conjunction wi~h such burner-produced reducing gases, to
augment the latter.
The term "non-circulating" in the claims is in contra-
distinction to a pool or bath of molten me~al which circulates in
a closed cycle in an annular or torroidal orbit about a vertical
axis, as for instance, in the ring-hearth furnace disclosed in
French patent 1,458,054.
¦ Figures 5 to 9 lllustrate an embodiment of the internal- 1
¦combustion burners 21 and 23;- the two (21 & 23) differing from
~each other only in their length beyond the combustion chamber 26
~thereof.
l i ~
$4Z70
The burners ~21 & 23) include a generally cylindrical outer
metallic shell 27, whose discharge end 28 may be tapered inwardly
towards the discharge end 29 of the burner. The shell 27 has an
l outwardly extending annual flange 30, preferably formed integrally
S ~ therewith, to which the closure or head 31 is bol~ed by means of
peripherally distributed bolts 32, so as to permit the periodic
opening of the outer end of the shell 27 when it is desired to
remove or replace the refractory lining thereof. A preferably
pre-formed cylindrical reractory liner 33 is mounted within and
supported by the shell 27. The liner 33 has a conical discharge
end or nose portion 34 which may also be formed as a separate
piece. The refractory liners 33 & 34 are fitted sufficiently
close to the inner metal shells 35 & 36 so as to obtain a good
heat-transference from the refractory liners ~o such metal shells.
An outer refractory closure disc 37 is provided across the
outer end of the cylindrical reractory liner 33 so as to complete
the refractory enclosure of the combustion chamber 26;- the
refractory disc 37 being held in place bythe head 31.
A cylindrical fuel-supply shell 38 extends through the head
31 and may be welded thereto by means of a suitable flange or
stuffing-gland or the like (not shown). The shell 38 extends
inwardly from the head 31 to a distance sufficient to reach the
inner surface of the refractory disc 37, and is provided with an
in-turned inner terminal flange 39. The outer end of the
cylindrical shell 38 is provided with an in-turned flange 40. A
cylindrical member 41 extends through the outer flange 40 of the
fuel-shell 38 and is preferably welded thereto by a suitable
fillet weldment (not shown~. The~-inner end of the cylindrical
member 41 terminates at the inner periphery of the in-turned
flange 39 and is preferably welded thereto. A suitable number and~
size of equi-distantly spaced fuel-exit holes 42 are provided in
¦ the in-turned terminal flange 39, eithe~ paràllel to ~he axis of
~ I
~ - 12- l~
~.~S4~
the burner or prefera~ly inclined inwardly at a suitable angle, so
as to discharge the fuel in a number of inwardly-directed jets.
The fuel ~scharge holes 42 are preerably also inclined
tangentially so as to cause the jets of fuel issuing therefrom to
create a swirling turbulence within the combustion-chamber con-
ducive to rapid and complete combustion.
The outer end of the cylindrical member 4L is closed by the
closure member of disc 43 having a central opening therein. A
gl~nd-like collar 44 is welded to or formed integrally with the
disc 43 (by casting or the like). A high-temperature ceramic
electrode-encasing rod 45 extends through the gas-pressure-tight
stu~fing-gland 44 and is adjustably supported therein~ so that it
~` can be extended into the cylindrical member 41 to the desired
extent for optimum ignition. A pair of ignition electrodes 46 & 47
are insulatedly embedded in and extend through the insulating
~ ceramic rod 45, with their innermost ends extending therebeyond
i and angled towards each other to provide a spark-gap 48 in opera-
tive juxtaposition to the fuel-jets issuing fro~ the fuel-exit
holes 42. Lead-wires 49 & 50 extend from the electrodes 46 ~ 47
to any suitable source of intermittent of continuous current of
sufficiently high voltage to provide a suitable ignition spark
at the gap 48.
The nose-section 51 of the burner may be long, as in the case
of the burners 21, or may be very short, as in the case of the
side-mounted burners 23. The nose-section 51 of the burner is
surrounded by the inner metallic cylindrical shell 35 and conical
nose-portion 36 thereof generally parallel to the outer metallic
shells 27 & 28;- providing an annulus-shaped space 52 between such
inner and outer metallic shells~ The innermost ends of the conica
shell-portions 28 & 36 are bridges and connected by a transverse
conical closure 53 welded to such innermost ends. Circumferentially
spaced longitudinally extending radial divider plates 54 are
.~ ' ~
115~Z70
provided in the space 52 between the inner metallic shell ,
portions 35 & 36 and the outer metallic shell portions 27 & 28. 3
~I The innermost portions 55 of the plates 54 angle inwardly to
¦¦correspond to the angle of the conical shell-portions 28 ~ 36, and~Z
5 ~Iterminate at 56, short of the conical closure-member 53 so as to
¦~leave the fluid-passageway between the ends 56 of such divider
¦iplates 54 adjacent the conical closure-member 53.
A cylindrical member 57 surrounds ~he outer end of the outer ¦
cylindrical shell 27 to form the annulus-shaped lower header- 3
chamber 58 for the incoming or in-flowing collant and to form the
upper annulus-shaped header chamber 59 for the outwardly flowing
coolant.
The in-flow header-chamber 58 is bounded by the upper annulus~
shaped disc 60 and the lower annulus-shaped disc 61. The out- flow
header-chamber 59 is bounded by the upper por~ion o~ the cylind-
rical member 57 and the annulus-shaped disc 60 and the annulus-
. shaped disc or ring 62 welded to the upper end of the cylindricalshell 57. The upper ends alternating pairs of radial separators
. ¦ 54 extend through corresponding slots 63 in the annulus-shaped
20 disc or ring 61 and are welded to the edges of such slots and
i have their upper ends welded to the edges of slots 64 in the
annulus-shaped disc or ring 60. The slots 63 & 64 alternate with
each other.
The liquid coolant, generally cold water, enters through ~he
in-flow pipe 65 into the annulus-shaped header 58, and from there
the coolant flows downwardly between the outer shell (27 & 28) and~
the inner shell (35 & 36), through alternating longitudinal
passageways formed by the separator plates 54, until they reach
the lower ends of such shells, where the coolant flows to the l~
adjacent up-passageway (as l.ndicated by the arrows in Figure 5), 3
¦which up-passageways discharge into the upper annulus-shaped heade~
3~59, from which the coolant flows outwardly through the out-~low
pipe 66 (as indicated in Figures 5 to 9).
1~ 1,.
~54Z7~
Air or oxygen (or any suitable combustion-supporting mixture)
is delivered to th~ annulus-shaped space 66 between the outer air
shell 41 and the ceramic electrode-holder 45. Gaseous ~or liquid)
fuel is delivered to the generally annulus-shaped space 67 between
the cylindrical shell 41 and the outer cylindrical shell 38, as .
indicated in Figures 5 & 9.
If it is desired to use a liquid fuel (as, for instance, any
suitable fuel oil), the ceramic electrode-bearing rod 45 is
removed, and in its place a liquid-fuel nozzle-assembly isinserted
with its atomizing nozzle-tip at approximately the same location
as the gap 48 between the ends of the electrodes 46 ~ 47. When
using such fuel-noæzle-assembly, the ignition for such atomized
fuel-oil may be provided by any suitable manual ignition means or
other suitable ignition means. In such event, the outer annulus-
shaped chamber 70 and the supply-pipe 69 thereto may be eliminated
or just closed off.
As used in the following claim, the term "processing" is
in~ended also to include refining.
It should be understood that the present disclosure is for
the purpose of illustration only and that this invention includes
all modifications and equivalents which fall within the scope of
the appended claims.
