Improvements in Ore Roasting Furnaces or Kilns.
Year: 1893

page_text: Date of Application, 1st Aug., 1893-Accepted, 2nd Sept., 1893
COMPLETE SPECIFICATION.
Improvements in Ore Roasting Furnaces or Kilns.
I, OWEN WARREN DAVIS, the Younger, of Middlesborough, in the County of
Bell and State of Kentucky, United States of America, Manufacturer 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 hereinafter described and the subject of the accompanying
application relates to ore roasting furnaces, of that class in which an annular ore
chamber or shaft surrounds a central shaft, and the products of combustion are
drawn across and through a narrow body of ore, instead of being drawn up through
an overlying mass; by reason of which transverse draft, the sulphur and other
fumes are carried directly into the smoke stack, and are more effectually removed
from the ore.
My said invention consists in certain details of construction in which I have
improved the form of the kiln above referred to in general terms.
These details are illustrated in the accompanying drawings, in which :-
Figure 1, shows in side elevation one half of the kiln, the other half being in
section.
Figure 2, represents a transverse section on line x-x of Figure 1.
Figure 3, is a detailed sectional view.
Figures 4, 5, 6, 7 and
relate to a modified form of furnace.
The inner
In these drawings the annular ore chamber or shaft is shown at B.
wall H of the ore chamber separates it from the central stack L. The outer
wall M is provided with a series of apertures E, which lead from combustion
chambers F, into the ore chamber. These combustion chambers are arranged in an
annular space between the wall M, and the outer wall N. These combustion
chambers are sections of the annular space between the walls M and N, this space
being divided to form the chamber by cross walls n. I have shown in Figure 1, a
vertical section of one of these combustion chambers, with a flue for the admission
of gas to said combustion chamber. This leads from a main below, but the gas
may be admitted above, or from any other point. This gas flue is shown at R and
has an opening 3 for the air beneath it, extending to the bottom of the combustion
chamber, while an exit opening or openings is formed in the top of the flue R as
at n opening into the combustion chamber. In the wall N, are apertures G, for the
admission of cold air.
therefrom into the combustion chamber.
I have also provided in, the wall M, air passages I, which have apertures i leading
The passages I have communication with
any suitable source of air, and the air in its passage through the wall M is heated.
By these apertures G or i, either hot or cold air may be admitted to the combustion
chamber. The gas is thus consumed in the series of combustion chambers, in the
presence of the air either hot or cold, and the products of combustion pass through
the apertures E, into the thin annular mass of ore. The apertures J in the inner
wall are in series of one above the other, one series opposite to the apertures E, of
every combustion chamber and the products of combustion are therefore drawn
across the thin mass of ore, and through the apertures J, into the central stack,
and thence escape through the smoke flue L' upward, or downward through the
flue K.
Over the central stack, is a conical roof (), the edges of which terminate at the
inside of the annular ore chamber and rests on the inner wall, on which the cone
is suitably braced. An annular counter slope P, over the combustion chamber
terminates at the outer side of the annular ore chamber. The ore is dumped upon

page_text: the cone, and is thereby distributed to all parts of the ore chamber. This chamber
is made flaring downward, and as the space is thus constantly increasing downward,
expansion by heat is compensated, the ore moves more freely, and all tendency to
clinker or to adhere to the walls is overcome. Every part of the ore turns over,
and is thoroughly exposed to the action of the air and heat, as the mass descends
and is gradually heated in its progress.
The smoke flue for the upper draft, consists of a transverse pipe, m, taken
through the main stack into the interior and connecting on the outside with the
stack L¹.
Any suitable draft forcing means, such as a steam jet, may be used.
As to the thickness of the walls, the dimensions and proportions of the parts,
these may be left to the skilled workman.
In the form shown in Figures 4-8 I aim to buttress the inner wall of the
combustion chamber so as to resist the pressure of ore; to provide at the same time
for a circulation through the buttressing, and finally to provide horizontally
arranged combustion chambers instead of vertical as in the form above referred to.
In the drawings:-
:-
Figure 4, is a vertical section through a portion of a furnace constructed
according to my invention with horizontal combustion chambers.
Figure 5, is a horizontal section of the same.
Figure 6, is a side view of the combustion chamber wall.
Figure 7, is a vertical section of a furnace provided with vertical combustion
chambers and buttressed according to my invention.
Figure 8, is a view of the buttressed wall.
In these drawings is shown a stack 1 of a circular form but the invention is not
limited to this form, being applicable as well to any other. There are two parts of
the invention, the first relating to the buttressing vertical walls between the inner
and outer walls of the combustion chamber said wall being made of open work, or
solid or with lateral passages between divisions of the combustion chamber which
is divided by said buttressing wall into said sub-divisions. The second part relates to
a further sub-division of the combustion chamber by horizontal partitions with each
one of which I have shown a separate gas pipe and air inlet, making a series of
combustion chambers arranged horizontally one above the other.
The outer wall D is solid as usual except for the air inlets and gas inlets. The
inner wall C of the combustion chamber is formed with openings 2, leading to the
ore chamber. These are shown in section and front elevation as extending
across between the vertical sub-division formed by the buttressing walls E, the
buttressing walls connect the inner and outer walls above described, which form
the combustion chamber. The combustion chamber extends horizontally around
the furnace being supplied with gas and air as at a and b, respectively, these
chambers being arranged in a series one above the other, but each preferably
independently supplied with fuel. The horizontal walls of the horizontal chambers
thus aid to strengthen the structure and resist the pressure of the ore, but in.
order to still further add to the strength I divide up the horizontal chamber by a
series of vertical buttresses which extend from the inner to the outer wall of the
combustion chamber as at E.
These prevent the crushing of the wall between the horizontal partitions. The
vertical partition may mark the division walls of the opening to the ore chamber
and in this case the openings may be arranged out of line with each other as shown.
In order that the vertical partitions may not separate the horizontal chambers into
a series of independent chambers, I prefer to provide passages in these walls so that
there may be connections between all the compartments of each horizontal
chamber. While I have shown but one opening 2, leading from each combustion
chamber to the ore chamber, more may be provided if found desirable. As usual
the lower wall of the opening is inclined to prevent lodgment of the ore.
In Figure 7, I have shown a furnace with a vertical combustion chamber and
thus chamber is divided by a series of vertical partitions extending between the

page_text: front and rear walls of the chamber so as to buttress the same. In this case the inner
wall is shown at C', the outer wall at D' and the partition wall at E'. In this
form the openings to the ore chamber are in line with each other and the
buttressing extends from top to bottom as shown, openings may be left in the
partitions at intervals to allow circulation between the chambers. The stack is
shown at K.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is ;-
1. An ore roasting furnace consisting of a central stack, an ore roasting chamber
surrounding the stack with openings to the same, a series of vertically arranged
combustion chambers encircling the roasting chamber of substantially the same
height as the roasting chamber, and a series of openings to the roasting chamber in
its inner wall from the top to the bottom, said openings being in line with the
openings in the opposite wall of the roasting chamber.
2. An ore roasting furnace consisting of a stack, a roasting chamber surrounding
the same, a series of vertically extending combustion chambers surrounding the
roasting chamber and in communication therewith at various points in its height
from the top to the bottom thereof, a gas conduit at the bottom of said combustion
chambers having an outlet therefrom, and an air inlet-leading into the combustion
chamber above the gas flue.
3. In an ore roasting kiln an annular ore chamber, a series of combustion
chambers arranged around said ore chamber and communicating therewith through
a series of apertures in the intermediate wall and air passages in said wall having
apertures leading into the combustion chamber.
4. In an ore roasting kiln, a central draft space, a stack in connection therewith,
an ore chamber encircling said space, with a series of openings at intervals in the
dividing wall, a series of combustion chambers around the ore chamber and
communicating therewith, and a cap covering the upper end of the draft space.
5. In an ore roasting kiln having inner and outer walls forming a combustion
chamber, vertical buttressing walls connecting said inner and outer walls, and
forming sub-divisions of said chamber, said buttressing wall being formed in open
work or with passages, substantially as described.
6. In an ore roasting kiln, having inner and outer walls forming a combustion
chamber, vertical buttressing walls connecting said inner and outer walls and
forming sub-divisions of said chambers and horizontal dividing walls, substantially
as described.
7. In an ore roasting kiln having inner and outer walls forming a combustion
chamber, a series of horizontal walls sub-dividing said chamber, with suitable
fuel supply in connection with said combustion chamber, substantially as
described.
Dad thin 911
Ti 1002
SLOAN & LLOYD BARNES,
Castle Chambers, 26, Castle Street, Liverpool,
Agents for the Applicant.