Improvements in Rotating Furnaces.
Year: 1889

page_text: Date of Application, 20th May, 1889
Complete Specification Left, 27th Jan., 1890-Accepted, 1st Mar., 1890
PROVISIONAL SPECIFICATION.
Improvements in Rotating Furnaces.
I, Dr. GUSTAV OLBERG, of Dessau, Duchy of Anhalt, German Empire, Engineer,
do hereby declare the nature of this invention to be as follows:-
My invention relates to furnaces of cylindrical or nearly cylindrical form, that
rotate about a horizontal axis and are heated by gaseous fuel, and which are designed
for carrying out various chemical processes, such as the reduction and oxydation of
substances, the regeneration of carbonate of baryta, &c.
The object of the invention is mainly to produce a more vigorous automatic stirring
of the materials under treatment.
For this purpose the receptacle constituting the furnace proper, is so arranged,
relatively to the supporting parts, that the axis or longitudinal centerline of the said
receptacle forms an angle with the axis of rotation. When a furnace of this descrip-
tion revolves, the melted substances contained therein, will alternately flow from one
end of the furnace to the other and thus be stirred more actively than is otherwise the
case.
Another improvement has the purpose of keeping tight the joints between the ends
of the rotating receptacle and the flues for the supply of gaseous fuel and air, and the
eduction of combustion-gases. In view hereof the ends of the receptacle are made in
form of tubular projections (which are of course concentric to the axis of rotation),
and between these and the Blues rings of soft fireproof material are inserted, which
overlap the said projections and are adapted to slide thereon. These rings, which
rotate with the furnace, are adjusted from time to time to the proper position by
screws, or they are continuously maintained in contact with the faces of the flues by
springs.
In order to cool the lining of the furnace, I arrange between the said lining and the
iron shell thereof, longitudinal channels, which terminate at the heads of the furnace
in radial portions, the latter communicating with the outer air by holes in the said
shell.
Dated the 20th day of May 1889.
J. H. JOHNSON & Co.,
Agents.
COMPLETE SPECIFICATION.
Improvements in Rotating Furnaces.
I, Dr. GUSTAV OLBERG, of Dessau, Duchy of Anhalt, German Empire, Engineer,
do hereby declare the nature of this invention and in what manner the same is
to be performed, to be particularly described and ascertained in and by the following
statement:-
My invention relates to furnaces of cylindrical or nearly cylindrical form, that
rotate about a horizontal axis and are heated by gaseous fuel, and which are designed
for carrying out various chemical processes, such as the reduction and oxidation of
substances, the regeneration of carbonate of baryta, &c.
The object of the invention is mainly to produce a more vigorous automatic stirring
of the materials under treatment and to afford means for exposing to the full action
of the flames unmelted portions of the material, which would otherwise remain
immersed in the melted portion.
For this purpose the receptacle constituting the furnace proper, is so arranged,
relatively to the supporting parts, that the axis or longitudinal centreline of the said
receptacle forms an angle with the axis of rotation.

page_text: Another improvement has the purpose of keeping tight the joints between the ends
of the rotating receptacle and the flues for the induction of gaseous fuel and air and
the eduction of combustion gases. In view hereof the ends of the receptacle are made
in form of tubular projections or necks, concentric to the axis of rotation, and between
these and the flues rings of soft fire-proof material are inserted, which overlap the
necks and are adapted to slide thereon. With the said rings means are combined
for adjusting them, or continuously keeping them in contact with the faces of the
flues.
In order to cool the lining of the furnace, I arrange, between the said lining and
the iron shell of the same, longitudinal channels, which terminate at the heads of the
furnace in radial portions, the latter communicating with the outer air by holes in
the shell.
In the annexed drawings fig. 1 is a longitudinal sectional view of a furnace carried
out according to my invention. Fig. 2 is an end view thereof together with a
section through a chamber that encloses the furnace. Fig. 3 is a sectional plan of
the furnace and the chamber, fig. 4a sectional plan showing the connection between
one end of the furnace and the flues, and fig. 5 a section on line 1 K, fig. 4.
In fig. 1, A is the receptacle constituting the furnace proper. The same consists
in a cylindrical iron shell and a fire-proof lining. 1, 2 is the centreline of the
receptacle, while the line 3, 4 is the axis of rotation, the said line 1, 2 forming with
the line 3, 4 an angle, so that when the receptacle revolves, the melted substances
contained therein flow alternately from one end of the same to the other. The
receptacle is mounted in two round disks a, figs. 1, 2, 3, the centres whereof coincide
with the axis 3, 4, and it rests with these disks on the rollers i, journalled in bearings
that are fixed to the bed-plate p. To one of the disks a is secured a toothed ring b
gearing with a pinion c, which can be rotated by means of a worm-wheel s, worm w
and shaft m. The ends of the receptacle A form tubular necks j and h, being
concentric to the axis 3, 4, and which register with the respective stationary flue
portions or chambers k, 1. The chamber communicates by the channel d with a
regenerator D, and by the channel e with a regenerator E, while the chamber is in
like communication by the channels d', e¹ with the regenerators D', E. Combustible
gas and air may thus be admitted into the furnace from either end, after having been
heated in the regenerators through which admission takes place, while the gases pro-
duced by the combustion pass from the opposite end of the furnace through the
regenerator in connection therewith. Besides, the course of the gases and flames
through the furnace may be changed as in other regenerative furnaces. The recep-
tacle A is charged through the aperture n provided with a door n'. o is a charging-
funnel. Spy-holes for observing the progress of the operation carried out in the
furnace, may be arranged in the outer walls of the channels d and d. The whole
furnace is with advantage mounted on wheels, so that it may be removed from its
place, for instance in case of repairs.
As herein before stated, any rotation of the described furnace causes melted substances
contained therein, to flow from one end of the same to the other. The substances are
thereby more actively stirred than is otherwise the case, and a change of the portions
exposed to the flames and the gases is brought about. In melting processes the
unmelted parts of the material being immersed in the molten mass while the réceptacle A
is, for instance, with its right hand end at the bottom, will be brought under the direct
action of the flames, as shown at t, fig. 1, when the receptacle is turned by half a
revolution, especially if the course of the gases is changed at the same time. In cases
in which it is not considered advisable to let the melted mass run over the door n¹,
the furnace is rotated alternately one way and the other by a part of a revolution.
Another advantage of the furnace consists in this that the portions of the material
adhering to the walls of the receptacle A while being rotated, operate to protect, the
fire-proof lining against the direct action of the flames, while on the other hand
such portions of the lining as have for a time been exposed to the flames, give
off heat to the molten mass when they are turned down so as to be brought below
the same.

page_text: .
The device for keeping tight the joint between the neck h and the chamber l, is
shown by fig. 4. This device consists in the ring r, made of fire-proof material
being softer than that whereof the chamber or flue-part 1 is constructed, and which
ring is formed on one side to overlap the neck and to be capable of adjustment
thereon, while with its other side it bears against the face of the said chamber. On
the ring is clamped an iron ring f; to the end of the shell are fixed brackets fl;
from the ring screws y extend through the holes in the said brackets, and on these
screws springs g are placed, which bear with one end against the brackets and with
the other end against nuts 2 on the said screws, so that when the nuts are duly
adjusted, the springs will press the ring r against the face of the chamber 1.
When the joint between the ring and the chamber becomes leaky through abrasion of
the former, the springs are compressed anew by the nuts f. The springs may, how-
ever, be omitted, the nuts only requiring in such case to be drawn tight again after
shorter intervals. The arrangement of the ring r¹ and parts belonging thereto is the
same as that described relatively to the ring r.
Of the aforesaid channels arranged between the shell u and the lining of the
furnace, one is shown in fig. 4 and marked x, while ¹ is the radial portion thereof,
and y one of the holes in the shell through which the channels communicate with
the outer air.
For the purpose of utilizing the heat radiating from the furnace, the same may bo
placed in a chamber B, fig. 3, having near the bottom orifices for the admission of
air, the warmed air being conducted to a drying chamber, or employed in other
manner. zare doors through which the furnace, if mounted on wheels, may be
removed from the chamber.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
1. A furnace consisting in a rotative receptacle A, the longitudinal centerline 1, 2
whereof forms an angle with the axis of rotation 3, 4, the said receptacle having
tubular necks j, h, concentric to the axis 3, 4, through which combustible gas and air
pass into the receptacle and combustion-gases issue therefrom, substantially as
described.
2. In a furnace, the combination of the rotative cylindrical receptacle A having
tho tubular necks j, h, two circular disks a in which the receptacle A is mounted
so that its centerline 1, 2 forms an angle with the common centerline 3, 4 of the
disks, rollers i carrying the disks, means for rotating the receptacle, and flues com-
municating with the necks j, h, and serving for the induction of combustible
gas and air and for the eduction of gases produced by combustion, substantially as
specified.
3. In a furnace, the combination, with the necks j, h of the rotative receptacle A
and the flue-portions k, l, of fire-proof rings r, r, iron rings surrounding the same,
and adjusting-screws g, with or without springs g, the said screws connecting the
rings with the shell u of the receptacle A, and being adapted to press the rings r, rl
against the face of the flue-orifices, substantially as described.
4. In a furnace the rotating receptacle A, composed of the shell u having holes y,
and a fire-proof lining having the channels x, x¹, communicating with the said holes,
substantially as set forth.
azah of Janu 1800