Improvements in and relating to Mechanically Calcining Furnaces.
Year: 1898

page_text: Date of Application, 13th Aug., 1898
Complete Specification Left 12th May. 1899-Accepted. 22nd July, 1899
PROVISIONAL SPECIFICATION.
Improvements in and relating to Mechanically Calcining Furnaces.
JOSEPH GODFREY, of 55, Walter Road Swansea, Assayer, HENRY JOHN
HAYES, of 203, Eaton Crescent, Swansea, Commercial Agent, (in the County of
Glamorganshire, South Wales), do hereby declare the nature of this invention
to be as follows:-
-:
The revolving furnace is so constructed with an opening that instead of a fixed
plough being inside the furnace an opening is made in which is fixed an adjust-
able plough exposed to the air wheels by a mechanical arrangement can be made
to turn over the whole of the ore as the table revolves and such opening admit-
The mechanical
ting air helps very materially the successful calcining of the ore.
arrangement is a lever attached to the plough which moves its blades at various
angles and so causes the whole of the ore to be turned over as the iron bottom
revolves. In the present revolving furnaces there is no opening and the ploughs
in such furnaces being fixed ones inside, the ore is not so constantly and
regularly turned over and the ploughs therefore are exposed to the heat, and
destructive properties of the sulphur contained in the ore.
Doted this 12th day of August 1898.
J. GODFREY.
H. J. HAYES.
Improvements in and relating to Mechanically Calcining Furnaces.
We, JOSEPH GODFREY, of 55, Walter Road, Swansea, Assayer, and HENRY JOHN
HAYES, of 203, Eaton Crescent, Swansea, Commercial Agent, (in the County of
Glamorganshire, South Wales), 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: -
According to this invention the material to be calcined such as lead ores, sul-
phide ores containing lead, zinc ores containing lead, and other ores and materials,
are alternately heated in a closed furnace and exposed to the air out of contact
with the products of combustion, thus causing rapid calcination and preventing
fusion and volatilization of metals to any appreciable extent whilst the heat of
the furnace is in no way interfered with.
For this purpose we employ a novel form of furnace in which there is an
annular rotating bed.

page_text: 1
In such furnaces ploughs are usually fixed above the rotating bed in order to
rabble the material under treatment and direct it outwards to the discharge
opening.
Such furnaces have heretofore been completely covered by the furnace roof so
that the materials have been protected from the air during the whole of the
treatment and the ploughs have been fixed so that the material must of necessity
be discharged after a certain number of revolutions of the bed and they also
have been covered by the roof so that they are exposed to great heat which rapidly
destroys them although partitions have sometimes been used to screen them from
the direct action of the flame.
According to this invention a section of the roof is cut away leaving part of
the bed entirely uncovered the open section freely admitting oxygen into the
ore when it is being turned over by the ploughs. The ploughs also are adjustable
so that they can be set tangentially to the path of the material in order that
the material may be treated during any desired number of revolutions without
any of it being discharged and the ploughs are in the open air uncovered, by the
furnace roof and radial partitions adjustable in height so as to come close down
onto the material being calcined are provided at each side of the opening to
keep in the flame and to prevent the entrance of an undue amount of air into
the furnace, and so cooling it.
Figure 1 is a plan, and Figure 2 a vertical section on the line A-A (Figure 1),
of a furnace constructed according to this invention.
Figure 3 is a part right hand side elevation of Figure 1, in this view the
levers operating the parts are omitted. Figure 4 is a local section to a larger
scale on the line B B Figure 1.
a is the annular bed of the furnace (preferably covered with fire clay tiles or
other refractory material) free to revolve about a central column b, and sup-
ported by a ring of balls c, and rollers. On the under side of the bed aby there
is a ring of teeth e, driven by any suitable gearing f
The roof g and side walls of the furnace are fixed, being supported by the
central column b and by columns j. It will be observed that air can pass freely
beneath the furnace. are non-adjustable ploughs fixed on stems carried by
a fixed radial bar m. n are other ploughs in the form of flat vertical plates
pivotted at one end to the bar m and at the other to a moveable bar o operated
by a lever 2 pivotted at g. The roof is in the form of a segment of a circle
being entirely cut away above the ploughs so that these are in the open air.
rare radial walls extending from the central column 6 to the side wall's hand
up to the roof 9. The spaces between the bottoms of the walls and the rotating
bed a can be made more or less closed according to the depth of material on the
bed by adjustable plates ss which lie against the outer faces of the walls and
can be moved up and down by the levers & pivotted at u. vis the fireplace
and w the flue by which the products of combustion are led away. The material
to be calcined may be fed onto the bed a at the opening in the roof between the
walls or through a hole formed in the roof between the left hand wall and
the fire place v. When the ploughs n are set as shown in Figure 1 the material
is gradually carried to the circumference of the bed a as the latter revolves and
is discharged over its edge between the walls but if the ploughs n
tangentially the material is not discharged.
are set
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that
what we claim is:-
-
1. Calcining furnaces in which the material is alternately heated by the
products of combustion and exposed to the open air out of contact with them.
2. Caleining furnaces having a rotating bed and a fixed roof in the form of
a segment of a circle,

page_text: 3. The combination of the rotating bed ploughs above the bed and means for
adjusting the angle of the ploughs to the direction of motion of the bed.
4. Calcining furnaces substantially as described and illustrated in the drawings
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