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Патент USA US3100694

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Aug. 13, 1963
.
J. L. MASON, JR
3,100,589
CARBON BLACK MANUFACTURE
Filed Aug. 21, 1958
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\NVE'.NTOR
JAMES L. MASON, JR.
BY
Aug- 13, 1963
J. L. MASON, JR
3,100,689
CARBON BLACK MANUFACTURE
Filed Aug. 21, 1958
3 Sheets-Sheet 2
INVENTOR.
JAMES L. MASON, JR.
Aug.,13, 1963
3,100,689
J. L. MASON, JR
CARBON BLACK MANUFACTURE
` s sheets-sheet s
Filed Aug. 2l, 1958
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JAMES L. MASON, JR.
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United States Patent O
31,100,689
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ICC
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Patented Aug. 13, i963
2
compositions compounded with such blacks. For other
3,1%,639
james Lawrence Mason, lr., Philadelphia, Pa., assigner,
CARBÜN BLACK MANUFÀCTURE
purposes, a low or moderate oil absorption or structure
is more desirable.
A known way of controlling oil absorption, within
limits, is by the selection of the feed stock to be de
composed for producing the carbon black. It is known
Fiied Aug. 2l, 195e, Ser. No. ’lâe?i?iil
that the use of paraffinic type feed stocks normally tends
7 Claims. (Cl. 23--2‘.l9.6)
totproduce carbon blacks of low oil absorption for a
given meanI particle diameter. On the other hand, the
This invention relates to the manufacture of carbon
black and, more particularly, to improvements in proc lO use of aromatic oils generally tends to produce carbon
blacks of relatively higher structure and high oil ab
esses therefor of the type in which a hydrocarbon oil,
sorption. However, the oil absorption characteristic of
or similar liquid carbon-containing compound, is sub
a carbon black is normally very difficult to control in
jected to partial combustion in a relatively quiescent zone
dependently of surface area and charging stock.
withl a restricted amount of oxygen, whereby a portion
Usually infurnace operation, conditions, such as air
of the oil is burned and the remainder is decomposed
ratios and the like, are so set as to produce a carbon
to carbon black by the heat thus generated.
black of the required iineness, the oil absorption being
A process of this type has been described and claimed
independently controllable only within a relatively nar
in United States Patent 2,779,665, in accordance with
row range.
`
which a gently-ñowing, relatively uniform current of air
A disadvantage of using parañinic oils for producing
is passed upwardly through the lower end of an unob~
carbon blacks of low oil absorption is that the yield of
stiuoted, vertically-elongated, heat-insulated furnace
carbon black per gallon of oil is relatively low. The
chamber and a gas-atomized spray of liquid hydrocarbon,
by mesne assignments, to Columbian Carlton Company,
New York, NSY., a corporation of Delaware
of high molecular weight and high aromaticity, initiated
aromatic feed stocks inherently produce higher yields,
in the lower end of the chamber, is injected upwardly into
the chamber, at a relatively high velocity, in contact with
the air, whereby a portion of the hydrocarbon is burned
in the lower end Vof the chamber and there is established
but also higher structure.
The present invention provides method and means
whereby the oil absorption characteristics of a carbon
in the furnace chamber above the zone of combustion
independently of the feed stock used and independently
a lazy, substantially non-oxidizing or reducing upwardly
of the particle size range of the resultant black.
The invention also provides means whereby the pro
duction‘rate of a given furnace may be greatly increased
rising atmosphere of hot furnace gases at a temperature 30
above the decomposition temperature of the remaining
hydrocarbons.
p
In that operation, the hydrocarbon is sprayed upwardly
through the upwardly rising air and hot furnace gases
black may be controlled and varied over a wide range,
by increasing the charging rate without material change
in the quality of the carbon black produced.
The invention will now be described and illustrated
at an initial velocity suilicient to carry the spray high
into the chamber but insufficient to cause `it to impinge
on the upper wall thereof. The air is introduced into
the lower end of the furnace chamber in an amount much
smaller than that required to burn all of the hydrocarbon
with reference t0 the following drawings of which:
having high oil absorption characteristics, from highly
cular wall 2, «tapering inwardly at its upper end, and
constructed of suitable furnace refractory and heat-in
FIG. 1 is a vertical sectional view of a carbon black
furnace embodying means especially adapted to the carry
ing out of my improved process,
FIG. 2 is a transverse horizontal section along the
and at a rate, and in a manner, such as to establish a 40 line 2--Z of FIG. 1,
FIG. 3 is an enlarged somewhat fragmentary view,
uniform, non-turbulent upwardly drifting current through
partly in section, of an assembly used in accordance with
the chamber at a velocity within the range of 1 foot to
my invention for injecting the hydrocarbon oil into the
siX feet per second. Under these conditions, there is
furnace chamber, and
formed within the chamber a smoke blanket which fills
FIG. 4 is a graphic illustration of the increase in pro
the entire upper portion of the chamber extending down- l'
duction rate of a given furnace made possible by my
wardly for a distance approximating one-half to three
present invention.
fourths of the height of the chamber.
The `furnace of FIG. 1 comprises a vertical elongated
The process just described has been found especially
chamber 1 tof cylindrical cross-section surrounded by cir
advantageous in producing so-called high structure blacks,
aromatic oils, for instance creosote oils, cracked petro
leum residues, coal tars, coal tar oils and the like. The
present invention, in one of its aspects, constitutes an
sulating materials, as is well-'known to the art. The lower
end of the furnace chamber is provided with »a partition
3 of furnace refractory, beneath which there is an lair
improvement in the process of said Patent 2,779,665, but
its utility is not restricted to the specific operating con 55 chamber 4. A multiplicity of symmetrically positioned
airducts 5 extend through partition 3 through which air
ditions, or to the charging stock, therein described.
passes from the air chamber into chamber 1 for support
The oil absorption characteristics of a carbon black
ing the partial combustion of the oil.
have been recognized to vary with the aggregate surface
Combustion air is passed to the air chamber under
area of the black. As the mean particle diameter of the
60 moderate pressure from any convenient source through
carbon black particles decreases, its surface area, fre
conduit 6 which ente-rs tangentially into the annular air
quently expressed as square meters per gram, generally
duct 7 and passes therefrom into the air chamber 4
increases. However, the oil absorption of carbon blacks
through the downwardly directed, symmetrically posi
is also known to be influenced by a characteristic of the
tioned perforations 8.
black known as “st1ucture,” which is a joining together
The rate at which airis introduced `through duct 6 [is so
of the carbon particles to form reticulate chains. For a
regulated las to obtain the desired quantity of air passing
carbon black of a given mean particle diameter, a high
upwardly through chamber 1 at the desired velocity, usu
oil absorption characteristic is an indication of such
structure.
High structure is a desirable property of carbon black
for some purposes. For instance, blacks having high
structure improve the extruding properties of rubber
ally within the range of l foot to 6 `feet per second, and
more advantageously within the range of 1 foot to 3 feet
per second, calculated for a temperature of 2400o F.
The oil to be partially burned and partially decomposed
to carbon black is introduced into -the furnace chamber
3,1oo,ese
Et
by means of the spray assembly represented at 9 and
more clearly shown in FIG. 3 of the drawing and, with
reference to which, the assembly will hereinafter be more
lar passageway Sti formed by coaxially positioned cylin
fully described. n The resultant gaseous suspension of
drical walls Si and 312 and'end wall 33. Water or other
carbon black passes from the upper end of the chamber
cooling medium is discharged into the inner end of con
duit 3@ through pipe 34, iiows outwardly along tube 31
and is discharged through outlet tube 3S. The dead-air
space 29 is vented «through end wall E53»` at 36 and tube
Ithrough iiue 1G into »duct 1.1 leading to conventional car
bonblack separating and collecting apparatus, not neces
sar] here to describe.
An essential feature of the present invention is the
manner in which the oil is introduced into the furnace
dead-air space 29 positioned coaxially with respect to the
con-duit 28 and which, in turn, is surrounded by an annu
27 is held in position by lugs 37. Except as previously
noted, the various elements of the assembly may be
fastened together in any suitable manner, for instance by
chamber, since it is by variation in this feature of the in
vention that the «oil »absorption or structure'characteristic
of the resultant carbon black is independently controlled.
I have found most surprisingly that the oil absorption
welding las indicated at 3S.
at will and varied over a substantial range, independently
tures.
In practice, I have found it advantageous to fill the
spaces between the spray nozzles with a plastic refractory
characteristic of a carbon so produced can be controlled 15 material as protection from the high furnace tempera
of the type of charging'stock used 'and of the mean par
ticle :diameter of the carbon black particle, by injecting
As noted above, the oil absorption characteristics of
the carbon black may be controlled :and regulated, in ac
the oil into the furnace chamber as a cluster of parallel,
cordance with the present invention, gby varying the nurn
gas-atomized liquid sprays and varying the number of 20 ber of spray nozzles of the cluster. While I am unable
sprays of the cluster.
’
A spray assembly comprising a cluster of such sprays,
presently to account for this phenomena, I have found that,
for a given ltype of charging stock, the oil absorption char
acteristic of the resultant carbon black can be materially
which has been used with particular advantage in carry
ing out the present invent-ion, is illustrated by FIG. 3.
decreased by increasing the number of spray nozzles of
The assembly shown comprises a cluster of 8 closely 25 the cluster and, conversely, the oil absorption character
spaced, symmetrically arranged spray nozzles 9` so posi
istic can be materially increased by decreasing the number
tioned thattheir respective axes ‘are parallel. It will be
understood that the number of spray nozzles in the cluster
of spray nozzles of the cluster.
`
Where 1 to 3 spray nozzles are used, `as described in
may be varied considerably depending upon the desired
the above-noted Patent No. 2,779,665, a carbon black of
results. It »appears to be essential, however, that the 30 maximum structure, or oil absorption, for «the particular
spaces between the nozzles be closed against the upward
feed stock, is obtained. But as the number of spray
ñow of air. AIn the apparatus shown, the body of the as
nozzles is increased, other conditions remaining constant,
sembly meets that requirement.
the structure of the resultant carbon black has been found
The respective spray nozzles shown comprise an outer
to decrease. Similarly, as the number of spray nozzles is
hollow cap 11 internally threaded into sleeve I2 at 13. 35 increased, the oil load, i.e. charging rate to the furnace,
Sleeve 12 is in turn threaded onto the upper end of nipple
may be increased without material change in the qual-ity
^ 14 at 15 and the lower end of the nipple is threaded at
of the resultant black. I have, with advantage, used
16 into the cover plate i7 of the oil chamber 18 which
clusters of as many as 18 sprays. Clusters of even more
constitu-tes the upper end of the housing 19 and which is
than 18 sprays may be used but such large clusters tend
separated by partition 20» from steam chamber 21 in the 40 to occupy too great a proportion of the cross-sectional
lower end of housing 19. These spray nozzles fare spaced
area of the furnace chamber and operation becomes more
apart a distance of 1% inches-2 inches between centers.
idiiiicult to control.
'
`
The nozzle also comprises `'an inner element composed
This variation in oil absorption and structure can be
of a tube 22 threaded into partition 20 'at its lower end
effected, by my present method, regardless of the partic
and lopening into steam chamber l21. The passageway
ular «type of feed stock used, `as fwill be illustrated by the
through «this tube is constricted at its upper end to form
following speciiic examples.
an orifice -23 leading into the chamber within the hol
low cap 11. The upper end of tube ‘22 is surrounded by
EXAMPLE I
helical guides 24.
This operation was carried out in apparatus substan
In operation, oil under pressure is _forced from the oil 50 tially as shown in the drawings except that the number
chamber upwardly through the ‘annular duct su-rrounding
of spray nozzles in the `spray assembly used in the respec
tube Z2 and along the flights of the helical guides 25 into
tive runs was varied as indicated. The diameter of the
the cap 11. Steam under pressure passes «from steam
furnace chamber was 8.5 feet, I_D. The feed stock used
chamber 21 through tube 22 and is jetted ythrough orifice
in each of these runs was creosote oil, land in each run
23, forcefully impinging on, land atomizing, the oil land 55 the spread angle lTof the respective spray nozzles was about
the resultant mixture is sprayed into the furnace cham
30°. The number of sprays and other yoperating condi
ber through orifices 25 extending through cap `11.
tions used in each run land the characteristics of the re
It will be understood that the invention is not restricted
sultant carbon black lare set «forth in the following tabula
to the particular construction of the spray nozzle shown
tion:
bu-t that other nozzles adapted to the gas atomization of 60
Table I
liquid oils may be used. Most advantageous results have
been obtained using spray nozzles having an angle of
Run No ____________________________________ _.
1
2
3
spread of about 30i degrees.
In the assembly shown, steam under pressure is fed to
chamber 21 through steam conduit 26 which extends co 65 O11
axi-aily through tube 27 forming an annular passageway
28 through which «the oil, preferably preheated, is charged
under pressure to chamber 18.
p.s.l_ ___________ __
Calculated steam, volume at 300° F., . .h_
Initial spray nozzle velocity, ft./sec. (cale).
Au' velocity, {11./sec. (calc.) _______________ __
Color rating, ABC _______________ _.
Due .to the high temperature of the furnace chamber,
Oil absorption, gallons per 100 lbs.-.__
usually of the order of 2300° F. `or higher, there is danger 70 Yield,
lbs. per gallon _______________________ __
of coke-forming pyrolysis of the oil being passed to the
spray nozzles. I kavoid this difficulty by thermally insulat
Since ABC color value is an indication of mean par
ing `the incoming oil'frcm the high temperatures of »the
ticle diameter, it will appear that each of the carbon blacks
furnace chamber.
In the assembly shown in FIG. 3, I provide an annular
produced was of the same fineness and, in spite of that
fact and the »fact that the same feed stock was used in
3,100,689
5
ci 4the «resultant black was 50-51 and the oil absorption
val-ue was 12J-«12.4 `gallons of oil per 100 pounds of the
black. The increase in production rate was, of course,
due to an increase in chargingfrate, which would normally
result in `a marked change in the quality of the black
each run, the oil absorption characteristics of the black
dropped sharply with an increase in the number of sprays.
EXAMPLE I1
In each of `the following runs, the feed stock used was
a No. 6 fuel oil of relatively low arcmaticity. The appara
produced. However, by increasing the number of sprays,
in accordance with my present invention, it was possible
materially to increase the charging rate while maintaining
the quality of the black substantially constant. Thus it isY
acteristics of the resultant carbon black are set forth in 10 possible, in accord-ance with m-y present invention, by
the .following tabulation:
varying the number of sprays used, independently ‘to con
tus was the salme as that used in ythe preceding runs, ex
cept that the furnace diameter was 6\.5,feet, LD. The
number of sprays and operating conditions and> the char
trol the structure characteristics of the black |at -a given
production rate or to materially increase production »rate
Table 1I
while holding the structure of the black constant. ~
Run No _______________________________ __
1
Number oi sprays..
2
3
Air volume, M c.í.h
_
3
4
4
15
5
32
32
32
32
180
180
180
180
40
40
40
40
Calculated steam volume at 290° F., cih- 2, 520
Initial Vspray nozzle velocity, it./sec.
Oil, g.p.h_____-.
Atcmizing steam, p.s.
__
3, 360
4, 220
6,720
686
686
686
636
1. 43
1. 43
1. 43
1. 43
54
, 55
55
14. 5
2. 2
12. G
2` 4
10. 4
2. 6
8.0
2. 5
(calc.) _______________________________ __
Air velocity, It./Sec. (oalc.)__
____
Color rating, ABC _____________________ _.
Oil absorption, gallons per 100 lbs ...... __
Yield, lbs. per gallon ___________________ ._
rThe characteristics of the respective oils used’ in the
foregoing runs are set iorth in 'the following tabulation:
8
Table IV
Creosote No. 6 fuel
oil
‘
Here also the iineness of the resultant carbon blacks 25
of the respective runs ywas practically the same, »as in
dicated by ABC color, and the changing stock was iden
tical. Neveritheless, there was a sharp decrease in oil
`>absorption value with the increase in the number of sprays
used.
~
`
EXAMPLE III
In
yfurther .series of runs using No. 6` fuel oil as 'the
charging stock in the furnace lof the preceding example
and under conditions set Vforth'in the following tabulation,
the indicated results were obtained:
Table III
oil
‘
4T
1829
1. 585
1. 0261
6. 4
.020
0. 82
1.34
220
1. 571
0.9779
13. 2
0. 004
0.76
8, 06
432
It will Ibe understood «that the invention is not restricted
30 to the speciiic types of foil illustrated ybut is applicable
generally to normally liquid hydrocarbons land similar
carbon-containing compounds, referred to collectively in
the appended claims as hydrocarbon oil.
In addition .to use in rubber compounding, the carbon
«blacks produced in accordance lwith my present invention
are well `adapted for other uses.
`For instance, the black
so produced having the higher oil ‘absorption characteris
G3
G3
192
50
192
50
tics are particularly useiul in the manufacture of dry cell
batteries, :and the lower oil absorption blacks are particu
40 larly useful in `the manufacture 'of electrical resistors, elec
trodes 'and the like. In rubber compounding, the blacks
of higher oil `absorption lare especially adapted for use with
synthetic rubber, while the lower oil absorption carbon
3,600
16,200
blacks are more desirable `for use in the compounding
Run No_____
1
Number of sprays ___________________________________ __
4
Air volume, M o.f.h_
Oil, g.p.h ___________ __
Steam pressure, psi _____________________ __
Calculated steam volume at 280° F., o.f.b______
_
Initial spray nozzle velocity, ít./scc. (calc.) .___ _
_
2
Air velocity, ít./scc. (calc.) ______ __
18
735
73
2. 8
2. 8
Color rating, ABC _____ __
6G
66
Oil absorption, gallons pe
13. G
12. 1
2. 4
2.6
Yield, lbs. per gallon _________ -_
It has heretofore been ‘found particularly diiiicult t0
vary independently the oil absorption characteristics of a
carbon black produced .from parafiinic type oils such ìas
No. 6 ifuel oil. The present invention provides means
_ whereby this can be readily accomplished. Also, as shown
of natural rubber.
Without intending to be 'bound to iany theory las to why
these surprising results »are obtained, I advance the follow
ing as »a possible explanation. Where :a single ‘spray is
used, the upwardly rising air is in Contact with the entire
periphery of that spray tand imay readily be drawn into the
interior :ot the spray by eduction. Where two or three
sprays are used, a very substantial proportion of the
periphery of ythose lsprays is also in contact with the
rising air. However, where the number yof sprays is in
by the yield increase in Tables II and III, the present in
vention provides means whereby the yield of carbon black 55 creased beyond three, there is developed within the in
terior of the cluster a zone in which there is a relatively
per `gallon of :oil used may frequently be materially in
high concentration of the hydrocarbon droplets. In con
creased, without decrease in mean particle diameter, by
junction with this, by reason of the A‘fact that the zone is
increasing :the number ‘of sprays used.
shielded on »all sides from the upwardly rising lair current
The air velocities 4given in `the foregoing tabulations were
by the surrounding sprays, and the fact that no air is per
calculated for a temperature of 240‘0‘“ F. The initial spray
mitted to rise between the spray nozzles, and the :fact that
nozzle velocities `and steam volumes are approximate
there is only a low degree 'of turbulence of the rising air
values calculated with-out taking into account expansion
by which it might be diffused into this zone, this zone of
due to temperature increase on leaving the nozzle, the
orifice discharge coeiiicient or the oil volume.
relatively high hydrocarbon concentration is also relatively
The relationship of permissible oil load to the number 65 îfree from oxygen.
As thc number of spray nozzle-s is increased, the hori
of sprays in the clusters used, lfor increasing production
zontal area of this zone will also be increased ‘and the
rate without change in quali-ty, is illustrated by the graph
shielding of this zone from the surrounding »air current
constituting FIG. 4 of the drawings in which the produc
will become even more eiîective. It is my present belief
tion rate in »pounds of carbon black per hour is plotted
against the number of sprays. In leach of these runs, the 70 that the surprising decrease in oil absorption is, in some
way, related to the lestablishing of this interior zone of high
feed stock was No. 6 fuel oil, hereinafter more fully de
hydrocarbon, and low oxygen, concentration.
scribed, and the ratio of air to foil was maintained at .33 : 1,
I claim:
as in the preceding Example Ill.
1. In the process ttor producing furnace caribou blacks
The furnace used in these runs was that used in EX
a-mples II land III. In each instance, the ABC color value 75 by the partial combustion of hydrocarbon oils whereby a
3,100,689
'7
gently-flowing, relatively uniform current of air is passed
upwardly through the lower portion of an unobstructed,
vertically-elongated Áfurnace chamber and the hydrocarbon
' oil is injected upwardly into 'the chamber as la high veloc
8
the oil into the furnace chamber as a cluster of closely
spaced, gas-atomized spray streams" having substantially
parallel axes of symmetry arranged about a central zone
substantially coaxially with the vertical axis ofthe fur
ity gas-atomized spray initiated in the .-l-ower end of the Ul nace chamber, the number of the spray streams in the
chamber, whereby «a portion of the hydrocarbon is burned
cluster being in excess of three, the number of spray
in the lower portion of the chamber ‘and there is estab
streams depending upon the desired low value in the oil ‘
lished inthe furnace chamber above said zone of combus
absorption «characteristic of the resultant black, the
tion a lazy, substantially non-oxidizing, upwardly rising
greater the number of oil streams, the lower the oil ab
»atmosphere of hot lfurnace gases at a tempenature above
sorption characteristic, the spray streams being Sulli
the :decomposition temperature of the remaining hydro
ciently close to form a protective barrier to the entrance
carbons, the improvement which comprises injecting the ' of kair laterally into said central zone, and shielding said
oil into the fur-nace chamber as 4a cluster of closely spaced,
central zone against passage of air upwardly thereinto.
gas-atomized spray streams having substantially parallel
7. In the process for producing furnace carbon blacks
Y axes of «symmetry arranged labout -a central Zone substan~
tially coaxially with the vertical axis of the furnace charn
ber, the number `of the spray streams in the cluster being
i-n excess of three, the spnay streams being suliiciently close
to form a protective barrier to the entrance of lair later
`al-ly into said central zone, and shielding said central zone
by the partial combustion of hydrocarbon oils whereby
a gently-flowing,y relatively uniform current of air is
passed upwardly through the lower portion of an un
obstructed, vertically-elongated furnace chamber and the
hydrocarbon oil is injected upwardly into the chamber
as a high velocity gas-atomized spray initiated in the
against passage of air upwardly thereinto.
2. The process of claim 1in which the upward velocity
f the air current through the furnace chamber is within
lower end of the chamber, whereby a portion of the hy
drocarbon is burned in the lower portion of the chamber
range of 1 foot to 3 feet per second.
maining hydrocarbons, the method of increasing the pro
and there is established in the chamber above said zone
the range of 1 foot to 6 feet per second.
of combustion a lazy, substantially non-oxidizing, up
3. The process of claim 2 in which the upward Velocity 25 wardly .rising atmosphere of hot furnace gases at a tem
of the air current through the chamber is within the
perature above the decomposition temperature of the re
'
4. The process of claim l in which the hydrocarbon
vused is a high molecular weight, highly aromatic residual
duction rate per unit volume of charging stock of a given
furnace by increasing the hydrocarbon oil charging rate,
oil.
30 without substantial change in the quality-of the resultant
5. The process of claim l in which the hydrocarbon
carbon black, which comprises injecting the oil into the
used is a fuel oil relatively high in paraffinic constituents.
6. In the process 'for producing furnace carbon blacks
furnace chamber as a cluster of closely spaced, gas- -
atomized spray streams having substantially parallel axes
by the partial combustion of hydrocarbon oils whereby a
of symmetry arranged about a central Zone substantially
Vgently-ilowing, relatively uniform current of air is passed
coaxially with the vertical axis of the furnace chamber,
upwardly through the lower portion of an unobstructed,
the number of the spray streams in the cluster being in
vertically-elongated furnace chamber and the hydrocar
excess of three, the number of spray streams depending
bon oil is injected upwardly into the chamber as a high
upon the desired charging rate, the greater the number
velocity gas-atomized spray initiated in the lower end of
vof spray streams the higher the charging rate, the spray
the chamber, whereby a portion of the hydrocarbon is 40 streams being sufficiently close to Iform a protective bar
burned in the lower portion of the chamber and there is
rier to the entrance of air laterally into said central zone,
established in the chamber above said zone of combustion
and shielding said central zone against passage of air
upwardly thereinto.
a lazy, substantially non-oxidizing, upwardly rising at
mosphere of hot furnace gases at a temperature above Athe
decomposition temperature of the remaining hydrocar
bons, the method of controlling the oil absorption characteristic of the resultant black which comprises injecting
References Cited in the ñle of this patent
UNITED STATES PATENTS
2,779,665
Heller _______________ __ Ian. 29, 1957
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